Question:
You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
innate immunity mediated through pamp recognition by prrs is the earliest stage of immunity against viral infection .
the subsequent modulation of the adaptive immune response by prr signaling has been studied using cells and mice deficient in specific tlrs , rlrs , or their associated signaling adaptor proteins .
recent studies demonstrated , for example , that the absence of specific tlr pathways impairs adaptive immune responses against a variety of viruses ( 18 , 19 ) .
rlr signaling also seems to be critical for the outcome of japanese encephalitis virus ( jev ) , vesicular stomatitis virus ( vsv ) , influenza virus , and encephalomyocarditis virus ( emcv ) infection ( 11 , 20 , 21 ) . in mice lacking rig - i ,
stimulator 1 , jev , vsv , influenza virus , and ecmv were more virulent and replicated to higher levels than in wild - type mice , suggesting that rlr pathways are essential for controlling infection by these viruses ( 11 , 21 , 22 ) .
for example , irf3 target genes induced by rlr signaling directly control viral replication in infected tissues ( 23 , 24 ) .
thus , depending on the nature of virus infection , tlrs and rlrs may work together or independently to mount an efficient immune response .
it is thought that the innate immune system protects the host from infection in a nonspecific way .
this , along with differences in cellular location likely serve to distinguish self - rna from nonself pamp rna , thus avoiding type i ifn induction in response to components of host nucleic acids . for example
, tlr7 recognizes a specific motif within uridine - rich ribonucleotide sequences ( 25 , 26 ) , which are hypothesized to be unique to rna viruses .
tlr9 recognizes dna pamp ligands and triggers signaling through the myd88 adaptor protein to induce type i ifn production ( 27 ) .
the recognition of nonself dna ligands by tlr9 might also be sequence dependent , and some studies have implicated the sugar - base - backbone sequence of pamp dna as a recognition factor ( 2830 ) .
unlike tlrs , which are found either on the cell surface or within membrane - bound vesicles , rlrs are found in the cytoplasm where cellular rna is also present ( 1 ) .
rig - i preferentially recognizes single - stranded rna ( ssrna ) over dsrna ( 15 , 31 ) .
ssrnas containing a terminal 5 triphosphate ( ppp ) , but not 5oh or a 5-methylguanosine cap , bind to the rig - i repressor domain and promote a conformational change that activates rig - i signaling ( 10 , 1316 ) .
rna ligands of rig - i are longer than 23 nucleotides , have a linear structure , and contain a uridine- or adenosine - rich ribonucleotide sequence ( 3133 ) .
host mrna , trna , mirna , snrna , and rrna are not ideal rig - i ligands because their length , structure , 5 end modifications , and interactions with ribonucleoproteins limit their recognition .
self - rnas therefore do not typically trigger innate immune programs or type i ifn expression ( 34 ) .
mda5 triggers innate immune signaling in response to emcv infection and synthetic dsrna , such as poly i : c ( 11 , 20 ) .
but ssrna viruses such as dengue virus and west nile virus , as well as reovirus , a dsrna virus , have also been shown to trigger signaling partially via mda5 ( 12 , 35 ) .
however , in these studies , mda5 appeared only to amplify type i ifn production as compared with rig - i , whose actions were essential to initiate innate immunity ( 12 ) .
( 17 ) in this issue describes a plausible mechanism of rna ligand recognition by mda5 , providing new insights into the differential roles of rlrs .
the study reveals that mda5 binding to dsrna does not depend on its 5 end modification , but rather on its length .
dsrnas with lengths of 2 , 3 , and 4 kb were shown to increasingly activate mda5 signaling , whereas rig - i recognized ssrna and , to a lesser extent , short dsrna motifs .
these results help explain how reovirus can trigger both rig - i and mda5 signaling .
the genome of reovirus comprises at least 10 segments of dsrna that vary in length , including long ( 3.9 kbp ) , medium ( 2.2 kbp ) , and short ( 1.2 kbp ) rna segments .
show that rig - i and mda5 recognize the short and long dsrna segments of the reovirus genome , respectively . in the case of emcv infection , the authors show that the viral genome forms long dsrna via its antisense replication intermediate , and this dsrna is recognized by mda5 but not by rig - i . on the other hand , vsv , which triggers rig - i  dependent immunity , forms medium - length dsrna replication intermediates that are not recognized by mda5 .
propose a model for pamp recognition by mda5 in which only long dsrna viral genomes or stable long duplex viral rnas formed during virus replication serve as mda ligands .
this model might explain why mda5 ignores self - dsrna , which is typically not present as long duplex rnas .
the current observations advance our understanding of how mda5 discriminates between potential rna ligands , but several questions about recognition of rna by rig - i and mda5 still remain .
it is widely accepted that ssrna viruses generate dsrna during their replication process ( 36 , 37 ) . however , only mda5 recognizes emcv ( 8 kb ) , whereas rig - i recognizes other viruses with lengthy rna genomes , such as vsv ( 11 kb ) , jev ( 11 kb ) , and hepatitis c virus ( 9.6 kb ) .
mda5 's failure to recognize these latter viruses may be due to their inability to form long or perhaps stable dsrna .
it is also possible that recognition by mda5 depends on specific compartmentalization of the pamp rna with mda5 , as differences in the subcellular site of viral genome replication may influence the pamp
the mechanism by which mda5 discriminates between pamp ligands in terms of their length is also unclear .
demonstrate that mda5 binds long , capped , di- or mono-5 phosphate dsrna , whereas rig - i binds to short dsrna or 5ppp uncapped ssrna .
when rig - i binds to 5ppp ssrna , it changes conformation , which disrupts the inhibitory interaction between the rig - i repressor domain and the cards .
this alteration results in the initiation of downstream signaling by the cards and exposes a 17- or 30-kd trypsin - resistant fragment corresponding to the rig - i repressor domain , thereby marking the activation of rig - i ( 10 , 15 , 16 ) . however , poly i : c binding to rig - i promotes a distinct conformational change that results in a 66-kd trypsin - resistant fragment , indicating that pamp - bound rig - i undergoes a distinct conformational change depending on the nature of its ligand .
structural studies validate that rig - i prefers ssrna ligands , whereas dsrna binds only inefficiently to rig - i , possibly due to constrains imposed by the location of basic residues within the rna binding groove of its repressor domain .
the charged residues are proposed to anchor 5ppp ssrna within the pocket , which would be less amenable to binding dsrna ligands ( 15 , 16 ) .
these observations suggest that rig - i may have two ways to distinguish different rna species : efficient recognition of 5ppp ssrna through its repressor domain ( 10 , 15 , 16 ) and comparably inefficient recognition and binding of dsrna ( 10 , 15 ) . by extension , these conformational alterations of rig - i might provide clues about how dsrna ligands interact with mda5 to stimulate its activation .
thus , mda5 might become active upon binding long dsrna through a ligand - induced conformation change that places its card into a signaling - active conformation .
this might involve dsrna interactions with its helicase domain and c - terminal region in a fashion similar to the binding of poly i : c to rig - i .
others have demonstrated that although very short dsrna ( 2030 bp ) fail to trigger rig - i  dependent signaling ( 15 , 17 ) , longer dsrnas ranging from 70 kb to 2 kb can at least weakly engage rig - i .
these data suggest that the length of dsrnas may dictate the interaction with the rig - i helicase domain and/or repressor domain in a manner that supports a rig - i  dsrna complex .
however , the mechanism of length discrimination of dsrna pamps by these rlrs has not yet been revealed .
the third rlr family member , lgp2 , has been defined as a regulator of rig - i signaling based on its suppression of rig - i function when overexpressed in cultured cells ( 10 , 38 , 39 ) .
however , recent studies imply that lgp2 may also function as either a positive or negative regulator of rlr signaling by forming a heterodimer with rig - i or mda5 when bound to rna ligand ( 40 , 41 ) .
such interactions between the rlrs may also broaden their pamp recognition profiles to accommodate other ligands , including ssrna or dsrna of varied length and composition , or even dna  rna duplexes .
structure and function analyses of rna interactions with rlrs or heteromeric rlr complexes will further define the molecular basis of self- versus nonself discrimination .
the rlrs are adenosine triphosphate ( atp ) binding proteins that hydrolyze atp as a result of binding rna ligand ( 15 ) .
however , the role of the atpase activity in the function of rlrs is not fully understood .
rlrs contain multiple domains , including two domains known as the walker a motif and the walker b ( also known as the dexd / h - box ) motif , each located within the helicase domain ( 42 ) .
walker a and b motifs comprise an atp binding region wherein specific amino acid residues contact the -phosphate of the nucleotide and mediate atp hydrolysis upon substrate binding ( 4345 ) .
mutant rig - i with an inactive walker a motif retains ssrna binding function but fails to trigger downstream signaling ( 15 , 46 ) .
thus , atp hydrolysis is not essential for pamp binding but is required for downstream signaling .
recent studies revealed that the rig - i repressor domain , in addition to binding to the rig - i cards , forms a complex with the helicase domain linker region that likely stabilizes rna ligand binding ( 10 , 15 , 16 ) .
moreover , it seems that motifs in the rlr helicase domain could also be involved in rna substrate binding according to structure and function studies of other dexd / h - box rna helicases ( 42 ) .
such studies indicate that the rna binding sites and the walker a and b motifs mediate specific interactions ( 47 ) .
these observations present a model in which a repressor domain  helicase domain internal complex forms an rna binding pocket whose association with pamp rna may serve to initiate the atpase activity of rig - i , which then triggers a conformation change that allows innate immune signaling .
the repressor  helicase domain interaction of rlrs may thus be the key determinant of pamp discrimination by rig - i and mda5 ( 15 , 17 ) .
it also seems that rig - i atpase activity is involved in the unwinding of dsrna ( 15 ) .
the importance of this activity for innate immune function is unclear , but it might support rig - i interaction with dsrna ligands by catalyzing their conversion to ssrnas .
the breadth of prrs expressed in different cells and tissues and their distinct intracellular distribution provide the means for pamp detection and immune activation against a variety of microbial pathogens at the local site of infection or in the  microbial niche .
these include the membrane - associated cytosolic replication sites of rna viruses , extracellular sites of microbe interaction , and endosomal sites of microbial trafficking and metabolism ( fig .
the recent identification of the dai ( dlm-1/zbp1 ) protein as a cytoplasmic sensor of microbial dna ( 48 ) suggests the existence of other prrs that detect cytosolic pamp dna .
it is reasonable to speculate that , similar to tlrs and rlrs , the cytoplasmic dna sensor molecules also exhibit ligand specificity to cover a variety of dna pamps in association with their specific microbial niche , thus providing a further basis for self- versus nonself discrimination .
understanding the processes of pamp ligand recognition within each microbial niche will provide a foundation for the design of appropriate vaccines , adjuvants , and immunotherapies .

Answer:
retinoic acid  inducible gene ( rig)-i  like receptors ( rlrs ) are cytosolic rna helicases that sense viral rna and trigger signaling pathways that induce the production of type i interferons ( ifns ) and proinflammatory cytokines .
 rlrs recognize distinct and overlapping sets of viruses , but the mechanisms that dictate this specificity were unknown .
 a new study now provides evidence for size - based discrimination of double - stranded rna ( dsrna ) by rlrs and suggests how host cells recognize a variety of rna viruses .


Question:
You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
maternal moderate and severe anemia have been considered as conditions that affect adversely maternal and perinatal outcomes .
for such reason the identification of these cases is important since appropriate treatment may reduce the risk for adverse outcomes .
iron is the most common treatment currently used to control iron deficiency and anemia particularly in low - income countries , where anemia is more frequent .
physiologically , hemoglobin concentration drops during gestation , and for such reason the hemoglobin cutoff to define anemia was set at 11  g / dl of hb .
maternal hb levels are higher at high altitudes in all trimesters of pregnancy than at sea level .
however , the reduction of hemoglobin levels during pregnancy occurs in populations at low and at high altitudes .
this is due to plasma volume expansion as a mechanism to improve arterial uterine flow to the placentae .
thus , a normal hb value at first booking in the first trimester does not preclude the presence of anemia in a second measurement of hemoglobin as pregnancy advances .
a recent study showed a higher risk for anemia in pregnant women with low body mass index ( bmi ) .
, anemia , particularly moderate and severe anemia is associated with high risk for low birthweight [ 3 , 9 , 10 ] , it is important to monitor hemoglobin values during pregnancy .
the present study has been designed to determine changes in hemoglobin concentration at second measurements after a normal hemoglobin concentration was detected at first booking during pregnancy at low and at high altitudes .
we will determine rates of anemia , normal hemoglobin values and erythrocytosis ( hb > 14.5  g / dl ) .
in addition , risk factors for moderate / severe anemia will be assessed in a multivariable analysis .
this is a secondary analysis of a large data base obtained from the perinatal information system in peru which includes 379,816 pregnant women and their babies obtained from 43 maternity units in peru .
data were obtained at the three geographical regions in peru : coast , highlands , and amazon .
the study was authorized by the institutional review board at the universidad peruana cayetano heredia .
as the study used secondary analysis of data , the study was exempt from formal review . from the total sample size
, a selection was made of all women diagnosed as nonanemic and without erythrocytosis at first booking ( hb ranging from 11 to 14.5  g / dl ) and having a second measurement of hemoglobin during the same pregnancy .
, 57,231 pregnant women were living at low altitude ( < 2000  m ) , 11,349 women at moderate altitude ( 20003000  m ) , and 20,714 women were living at high altitudes ( > 3000  m ) .
data on gestational age at first and second hemoglobin measurement were recorded . with a second hemoglobin value , rates of pregnant women with anemia ( hb < 11 g / dl ) , normal hemoglobin values ( 1114.5  g / dl ) , and erythrocytosis ( hb>14.5  g / dl ) were determined . as demonstrated previously , no correction of hemoglobin cutoff to define anemia at high altitude is needed ; hence , the present study used the definition of anemia as suggested who for populations at sea level [ 1 , 11 ] .
the degrees of anemia were classified as mild ( hb 9.010.9  g / dl ) , moderate ( hb 7.0 < 9  g / dl ) , and severe ( hb < 7  g / dl ) . body mass index was calculated from prepregnancy body weight and height .
low bmi was defined as < 19.9  kg / m and high bmi as > 25
altitude was defined as low ( 01999  m ) , moderate ( 20002999  m ) , and high (  3000  m ) .
the following perinatal outcomes were assessed : stillbirths , preterm deliveries and small for gestational age .
stillbirths were diagnosed when fetal deaths occurred after 20 weeks of gestation or with a weight higher than 500  g. preterm births were defined as deliveries before 37 weeks of gestational age .
small for gestational age was defined if birthweight was below the 10th percentile of the williams reference chart .
the adverse maternal outcomes assessed were preeclampsia , premature rupture of membranes ( prom ) , and postpartum hemorrhage ( pph ) .
preeclampsia was defined as the presence of pregnancy - induced hypertension ( systolic pressure of 140  mm  hg and/or diastolic pressure of 90  mm  hg ) and proteinuria ( 300  mg/24  h ) after 20 weeks of gestation .
pph was defined as women after parturition with blood losses of 500  ml or more .
data are assessed according level of altitude ( low , moderate , and high ) and according to degree of anemia ( moderate / severe and mild ) , and erythrocytosis .
if data were normally distributed , then a one - way analysis of variance were used ( anova ) .
data expressed in proportions were assessed by the chi - square test . the confidence interval ( ci )
the prevalences of women with moderate / severe anemia ( hb < 9  g / dl ) , mild anemia ( hb 910.9  g / dl ) , normal hemoglobin ( hb 1114.5  g / dl ) , and erythrocytosis ( hb > 14.5  g / dl ) were calculated for the total sample , as well as for groups at different altitudes ( low , moderate , and high altitude ) .
estimates of crudes and adjusted odds ratio ( or ) with 95% ci were computed as measures of association between the variables .
a logistic regression analysis to determine the risk for moderate / severe anemia at second hemoglobin measured was assessed .
the estimates were adjusted for gestational age at second hemoglobin , hemoglobin value at first measurement , altitude , maternal age , body mass index , maternal education , marital status , prenatal care visits , parity , the presence of preeclampsia , cardiopathy , and diabetes .
concentration of hemoglobin at first booking in nonanemic women increased as altitude increased ( p < 0.05 ) , whereas birthweight decreased as altitude increased .
no differences were observed in gestational age at birth at the three altitude groups studied .
concentration of hemoglobin at second measurement also was increased as altitude increases , but values were lower than those at first measurement , particularly at low altitude , in which values were reduced to 94% , whereas at moderate altitude . they were reduced to 98.4% and at high altitude to 99.2% .
gestational age at first and second hemoglobin was higher as altitude of residence increased ( table 1 ) .
most of the studied sample remained with normal hemoglobin values at second hemoglobin measurement ( 75.1 ) .
however , 21.4% of women became anemic at the second hb measurement . in all , 2.8% resulted with moderate / severe anemia and 3.5% with erythrocytosis ( figure 1 ) .
women with anemia in the second hb measurement showed lower hb measurements in the first hb .
conversely , women with erythrocytosis at the second hb measurement showed higher hb levels in the first measurement ( table 2 ) . in all cases hb was higher as altitude increased .
the rate of stillbirths was higher with moderate / severe anemia and with erythrocytosis ( p < 0.05 ) , which remained higher after controlling for confounders ( table 3 ) .
the rate of preterm births was increased in women with severe anemia ( 9.01% ; or = 1.81 ) . after adjusting for confounders , moderate / severe anemia ( or = 1.73 ) and mild anemia ( or = 1.28 ) were risks for preterm deliveries ( table 4 ) .
the rate of sga was significantly higher in mothers with erythrocytosis , almost twice , than in women with normal hemoglobin .
lowest rate of sga was observed with a maternal hb level of 910.9  g / dl ( mild anemia ) ( table 5 ) .
the rate of preeclampsia was significantly higher in moderate / severe and mild anemia and in mothers with erythrocytosis , which remained after controlling for confounders ( table 6 ) .
the highest risk for pph was observed with moderate / severe anemia ( twenty times higher than in woman with normal hb levels ) ( table 8) .
an increased risk for moderate / severe anemia was associated with higher gestational age at second measurement of hemoglobin , bmi < 19.9  kg / m , living without partner , prenatal visits care < 5 , first parity , multiparity , and preeclampsia .
lower risk for moderate / severe anemia were observed with normal high hb level at first booking , living at moderate and high altitude , and with high bmi ( table 9 ) .
the present study has been designed to determine changes in hb levels after a first hb measurement in 89,294 pregnant women detected normality ( hb 1114.5  g / dl ) . according to the study results
an increase in the rate of anemia according to pregnancy progress has been previously published in other settlings .
moderate / severe anemia has been characterized as the conditions more associated with maternal and perinatal adverse outcomes .
our results demonstrated that 2.8% of women classified as nonanemic in the first hb measurement showed moderate / severe anemia in the second measurement .
our data showed that moderate / severe anemia were associated with stillbirths , preterm births , preeclampsia , and pph .
the strength of this study is that it was done thanks to a large sample of women recorded through a perinatal information system that included 379,816 pregnant women and their newborn babies from different maternity units throughout peru .
this database is an important tool for monitoring conditions and trends related to pregnancies and newborns , including service characteristics and women 's risk factors .
data revealed that a percentage of women became anemic during the progression of pregnancy despite having a first normal hb measurement .
this is an important finding since moderate and severe anemia are harmful for mothers and neonates .
risks for moderate / severe anemia are preventable , or can be managed through appropriate management , such as with prenatal care , parity , preeclampsia , and low bmi .
increasing the number of prenatal visits will result in better monitoring of hemoglobin values , and can control or reduce the effect of preeclampsia .
low bmi is a characteristic of low - income countries and is associated with increased risk of maternal anemia , low birthweight , and preterm births .
the present results are in accordance with other studies where low prevalence of anemia was observed in women with highest bmi , and high prevalence of moderate / severe anemia were associated with malnutrition [ 14 , 15 ] .
our data suggest that in situation in which a normal hemoglobin value was first observed in a woman with low body mass index , supplementation with iron should be recommended .
it is interesting to note that populations living at moderate and high altitudes had lower risk for moderate / severe anemia in a second measurement of hemoglobin during pregnancy .
this suggests that women living in these altitudes bearing normal hemoglobin values at first booking should not be treated with iron supplementation . in recent years
, it has been demonstrated that anemia defined as less than 11  g / dl of hb is lower at moderate and at high altitudes , since populations at these altitudes are characterized by increased hemoglobin values to compensate for the effect of altitudinal hypoxia [ 3 , 10 ] .
however , we assumed that most cases of anemia were related to iron deficiency , which was supported by the finding that low bmi was associated with moderate / severe anemia .
however , results of our analysis were similar to those obtained in a study in which bmi was obtained at first prenatal care .
it is possible that erythrocytosis found in the second measurement of hb after a normal value of hb at first booking could be due to the effect of iron supplementation , since in peru a ministry of health regulation orders pregnant women be supplemented with iron .
however , low adherence may explain the low prevalence of erythrocytosis in a second hb measurement during pregnancy .
the results of this study confirm that prevalence of anemia increases as pregnancy progresses and that a normal value at first booking should not be considered sufficient , as further hb values should be indicated and observed during the course of pregnancy .

Answer:
objective . to determine changes in hemoglobin concentration at second measurements after a normal hemoglobin concentration was detected at first booking during pregnancy at low and at high altitudes
 . methods .
 this is a secondary analysis of a large database obtained from the perinatal information system in peru which includes 379,816 pregnant women and their babies from 43 maternity units in peru
 . results .
 most women remained with normal hemoglobin values at second measurement ( 75.1% ) .
 however , 21.4% of women became anemic at the second measurement .
 in all , 2.8% resulted with moderate / severe anemia and 3.5% with erythrocytosis ( hb>14.5  g / dl ) . in all cases
 hb was higher as altitude increased .
 risk for moderate / severe anemia increased associated with higher gestational age at second measurement of hemoglobin , bmi < 19.9  kg / m2 , living without partner , < 5 antenatal care visits , first parity , multiparity , and preeclampsia .
 lower risk for moderate / severe anemia was observed with normal high hb level at first booking living at moderate and high altitude , and high bmi .
 conclusion .
 prevalence of anemia increases as pregnancy progress , and that a normal value at first booking may not be considered sufficient as hb values should be observed throughout pregnancy .
 bmi was a risk for anemia in a second measurement .


Question:
You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
in the outpatient setting , actinic keratosis is one of the most commonly treated skin conditions , the prevalence of which increases with cumulative skin exposure and increasing age .
rates of 1125% have been reported in the northern hemisphere and of 4060% in australia .
actinic keratoses are strong predictors of squamous cell carcinomas and are believed to be precursors of squamous cell carcinomas of the skin .
a number of studies have been published recently concerning modalities of photodynamic therapy ( pdt ) treatment for actinic keratosis in which the efficacy of several photosensitisers and/or light sources were compared , , , .
the most recent of these is the study by dirschka and colleagues   which appeared recently in the british journal of dermatology and in which a gel formulation of 5-aminolaevulinic acid ( bf-200 ala ) was found to be superior to methyl-5-aminolaevulinate ( mal ) . in the same study ,
the narrow - band light sources were found to be more effective than the broad - band light sources , although the narrow - band sources were associated with a higher occurrence and severity of adverse effects , which included pain , burning , erythema and exfoliation , irrespective of the photosensitizer used .
while such a multicenter , randomized study is to be commended , the authors  in our opinion  failed to appropriately consider their findings in the light of previous studies , since a number of pertinent and highly relevant articles were not mentioned .
an important study in this context is the study by von felbert and colleagues   with a longer follow - up time of 12 months ( compared to 12 weeks in the study of dirschka et al . ) and in which the use of narrow - band and broad - band sources were found to be equally effective .
one reason given by von felbert and colleagues   for the comparable efficiency of these sources was the use of a more advanced and efficient broad - band optical filter ( in comparison to the broad - band sources used in previous studies ) .
however , not only failed to discuss reasons for the differences between the narrow - band and broad - band types of sources used , but also did not comment on the differences found between the various types of broad - band sources employed . additionally , despite the findings of von felbert et al .   who found the use of a broad - band source with water filter to be associated with less pain than that caused by a narrow - band source , and a study by apalla et al .   who found the use of a broad - band source without a water filter to be associated with pain , dirschka and colleagues did not consider the fact that broad - band sources would result in absorption over a broader spectral range ( and possibly encompassing several maxima ) of the photosensitizer as has been discussed previously
additionally , previous studies in which no differences were found between narrow- and broad - band sources , ,   were not considered .
their study also demonstrated that the conditions under which pdt was applied had a pronounced impact on the efficiency of the treatment .
for mal , the von felbert study   also found considerably higher response rates ( 80% total clearance ) as compared to the dirschka et al .
possible reasons for such a pronounced difference between the response rates in these two studies were however not discussed by dirschka and colleagues . while the extent of pain experienced during photodynamic therapy ( which is deemed to be the main side - effect of pdt , ) was documented by dirschka et al . , possible reasons for the greater incidence of pain during the use of the narrow - band sources were not considered . in the dirschka et al .
study , a comparison of the photosensitizers used showed bf-200 ala to be superior to mal , but again , a study with contradictory findings ( gholam et al . ) is not discussed .
while we do not wish to infer that the study performed by dirschka and colleagues is in any way erroneous , we would nevertheless like to point out that the discussion of the results and the authors selection of cited literature appears to be biased towards studies supporting the authors own findings .
the problem of such a bias has recently been outlined , together with the need for an up - to - date selection of literature and the recommendation that a concealment of contradictory or critical literature should be avoided .
as a result of the rather selective choice of literature provided and the lack of a thorough consideration of the relevant studies already published , the article by dirschka and colleagues   leaves a number of questions unanswered .
furthermore , the corresponding editorial published in the same issue of the british journal of dermatology   is unfortunately also based on the acceptance of the  superiority  of bf-200 ala in comparison to mal as well as the  superiority  of narrow - band in comparison to broad - band sources and fails to address the fact that several other studies have found contradictory results .
certainly , sweeping statements claiming e.g. , narrow - band sources to be preferable to broad - band sources or bf-200 to be better than mal should not be made on the basis of a single study , especially since such statements may lead to rapid and ungrounded propagation of therapeutic protocols . in conclusion
, it would appear that the last word concerning the optimal photosensitizer and radiation source for the treatment of actinic keratosis has not yet been spoken .
therapy for actinic keratosis should be a carefully chosen compromise between undesired side - effects and therapeutic efficacy and needs to be based on a consideration of all of the relevant clinical studies .

Answer:
actinic keratosis is one of the most commonly treated skin conditions .
 a number of studies have recently been published on the treatment of this ailment using photodynamic therapy .
 the authors of this letter are concerned about the interpretation of some of these studies and would like to outline possible misinterpretations which may arise due to an incomplete analysis of the study reports available .
 clearly , the  ideal  therapy for actinic keratosis should be a carefully chosen compromise between undesired side - effects and therapeutic efficacy and needs to be based on a consideration of all of the relevant clinical studies .


Question:
You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
in march 2013 , cases infected with a novel reassortant avian - origin influenza a ( h7n9 ) virus emerged in china and had high mortality . that month
, a patient with h7n9 influenza was admitted to our hospital , and daily lung ultrasound was performed . a 54-year - old woman , who ran a convenience store beside a poultry market , complained of cough and high fever for 4 days .
her temperature was 38.6c , and she had a heart rate of 113 beats per minute and a respiratory rate of 26 breaths per minute .
her white blood cell count was 2.7  10/l , and neutrophil , lymphocyte , and monocyte levels were 72.4% , 22% , and 5.2% , respectively .
her partial pressure of oxygen in arterial blood was 72 mm hg , and her fraction of inspiratory oxygen ( fio2 ) was 40% .
avian - origin influenza a ( h7n9 ) virus was confirmed from the pharyngeal swabs by real - time reverse transcriptase - polymerase chain reaction .
treatment with oseltamivir ( 150-mg capsule taken by mouth twice a day ) was initiated , and she was admitted to an isolated room in the infectious diseases department .
bothell , wa , usa ) with c60 convex probe ( 2 to 5 mhz ) was performed , and the lung ultrasound score ( lus )   was recorded , and both effectively reflected the progression of pneumonia ( figure 1 ) .
dynamic changes of chest computed tomography ( ct ) , radiography , and lung ultrasound in a patient with h7n9 influenza .
( a - c ) ct showed pneumonia in the left upper lung , with partial consolidation on admission .
( d - f ) lung ultrasound corresponding to ct in ( a - c ) showed multiple abutting b2 lines , and some regions presented a tissue pattern ( arrow ) .
( g - i ) ct on day 6 after admission showed that the pneumonia was partially absorbed .
( j - l ) lung ultrasound corresponding to ct in ( g - i ) showed that the number of b lines was obviously decreased , and the consolidation disappeared .
( m - o ) ct on day 9 after admission showed that the size of the lesion was obviously reduced .
( p - r ) lung ultrasound corresponding to ct in ( m - o ) indicated that only the a line and few b lines were visible .
( s - u ) chest radiography on days 1 , 3 , and 6 after admission showed no obvious change of the pneumonia .
( v ) dynamic changes of lung ultrasound score ( lus ) ( total of 48 for normal lung ) .
the onset of h7n9 influenza in this case was manifested by hyperpyrexia and flu - like symptoms and progressed to lobar pneumonia 4 days later .
chest radiograph is the routine tool for assessment of pneumonia , but its sensitivity and accuracy were not so good .
ct is regarded as the gold standard , but its application is limited in cases with this new emerging virus since strict protection should be followed to avoid person - to - person transmission .
ultrasound has many advantages , including convenience , rapidness , non - invasiveness , availability for repeated examination , and absence of radiation .
the right lung presented an a line with few isolated b lines , whereas the left lung presented multiple abutting b lines and consolidation . when the patient improved , both b lines and the area of consolidation were decreased and the lus was synchronously increased .
this case highlights that ultrasound can be an adjutant to chest radiography and ct in caring for patients with h7n9 influenza .
written informed consent was obtained from the patient for publication of this letter and accompanying images .

Answer:
h7n9 influenza is a new emerging infection and has high mortality .
 both chest radiography and computed tomography ( ct ) had some limitations in assessing such patients .
 we performed daily lung ultrasound in a patient with h7n9 influenza .
 lung ultrasound and lung ultrasound score showed high consistency with ct and the progression of pneumonia .
 ultrasound can be adjutant to chest radiography and ct in caring for patients with h7n9 influenza .


Question:
You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
phlegmon is a spreading diffuse inflammatory process associated with the formation of a suppurative exudate or pus .
phlegmonous infection may involve any gastrointestinal tract site , although the stomach is most frequently involved ( 1 ) . however , phlegmonous involvements of the esophagus , small bowel , or colon are rare ( 1 - 3 ) .
therefore , strong suspicion and recognition of this disease is a key to the diagnosis and prompt management of patients with acute symptoms .
however , the role of surgery has been questioned for the diffuse disease form ( 2 ) .
the authors report a rare case of acute diffuse phlegmonous esophagogastritis . in this case , proper radiologic diagnosis with typical chest computed tomography ( ct ) findings ( 4,5 ) enabled appropriate treatment and timely surgical intervention .
a 48-yr - old man presented with left chest pain , abdominal pain , and dyspnea of three days duration .
five days before admission , he had been involved in a minor motorcycle accident , but was asymptomatic for two days .
however , his vital signs were stable ; heart rate 70/min , respiration 37/min , blood pressure 110/80 mmhg , and body temperature 36.8. a physical examination also revealed no remarkable finding with normal bowel sounds and a soft , flat abdomen with no general or rebound tenderness .
laboratory tests revealed ; wbc 3,200/l , c - reactive protein 31.68 mg / dl , and serum glucose 201 mg / dl , and chest radiography on admission showed mediastinal widening and bilateral pleural effusion ( fig .
the patient underwent endoscopy on the admission day to exclude esophageal rupture , and diffuse thickening of mucosal folds with decreased distensibility and an 1 cm sized mucosal ulcer in upper thoracic esophagus were observed with scattered patches of hemorrhage in the gastric mucosa of the body and antrum . on the evening of first hospital day , the patient was became febrile with a body temperature of 39 , and thus , empirical treatment with broad spectrum antibiotics was immediately started under the suspicion of empyema or secondary infection . on the second hospital day ,
the dyspnea worsened and the amount of left pleural effusion increased on chest radiography . left closed thoracostomy was performed with pus drainage . on the forth hospital day ,
a contrast - enhanced chest ct scan was performed and showed diffuse and marked circumferential wall thickening of the entire thoracic esophagus , extending to gastric cardia and associated with diffuse intramural low density and a peripheral enhancing rim ( fig .
a ct diagnosis of acute phlegmonous esophagogastritis was suggested and bilateral open thoracotomies were performed immediately .
pleural fluid analysis revealed exudates and a surgery was decided due to worsening of clinical condition of the patient and radiologic findings . during surgery
, bilateral multiloculated pleural effusions were evacuated through open thoracotomies and the esophagus was freed from adjacent tissue .
the adventitial and muscular layers of the esophagus were intact and no perforation was identified .
several separate esophageal myotomies were performed and the submucosal layer was found to have been filled with thick , cheesy materials , which were removed from the mucosa by scraping .
blood and sputum cultures of the patient and a microbiologic examination of pleural fluid demonstrated klebsiella pneumoniae .
a follow - up chest ct scan performed on the 49th postoperative day showed reduced diffuse esophageal wall thickening and bilateral pleural effusion ( fig . 2c ) .
phlegmonous infection can affect any site of the gastrointestinal tract , although the stomach is most frequently involved ( 1 - 3 ) .
involvements of other sites have been rarely reported , but the simultaneous involvement of esophagus and stomach has only been reported in a very limited number ( 1 , 2 ) .
phlegmonous infection usually involves the submucosa and not the mucosa ( 1 - 3 ) .
diffuse esophagogastric involvement of phlegmonous inflammation was evident in our case by chest ct and during surgery . in its localized form , an area of acute inflammation in submucosa
phlegmonous infection may also present as a mass in the gastric wall ( 6 ) .
the inflammation produced may involve the muscularis mucosa and the serosa , and lead to perforation or even peritonitis ( 1 ) . in its diffuse form
, phlegmonous infection can involve the entire stomach , but it rarely extends beyond the cardia or pylorus ( 6 ) .
reported predisposing factors ( 4 ) include immune suppression , alcoholism , peptic ulcer disease , chronic gastritis or some other gastric mucosal injury , achlorhydria , infection , connective tissue disease , and malignancy .
presumably , these conditions predispose the stomach to infection by eliminating various defense mechanisms , such as , inherent gastric cytoprotection or the bactericidal effect of gastric acid ( 1 , 6 ) .
nevertheless , approximately 50% of reported cases were previously healthy and had no significant anteceding risk factors ( 6 ) .
we consider that uncontrolled diabetes mellitus and a recent history of chest trauma in combination with excessive alcohol consumption played an important role in the development of the disease in our patient .
histopathologically , the submucosa is thickened and infiltrated by neutrophils and plasma cells with intramural hemorrhage , necrosis , and thrombosis of submucosal blood vessels ( 1 ) .
the most common pathogens are streptococcus species , staphylococcus species , escherichia coli , haemophilus influenzae , proteus , and clostridia ( 6 ) .
streptococcus accounts for approximately 70 to 75% of cases , and it is also the organism most commonly associated with death caused by phlegmonous gastritis .
the causative pathogen of phlegmonous infection in our patient is believed to be klebsiella pneumoniae , based on positive culture results on blood , sputum and pleural fluid .
phlegmonous gastritis has rarely been diagnosed before surgery , because it is seldom considered in the differential diagnosis of an acute abdomen ( 3 ) .
other symptoms include nausea , vomiting , hematemesis , hiccups , prostration , and fever ( 6 ) . on the other hand , when the esophagus is involved , odynophagia , dysphagia , and chest pain are the most common symptoms ( 1 ) .
phlegmonous infection is usually diagnosed at surgery or at autopsy ( 3 ) , and because there are no pathognomonic signs or symptoms , phlegmonous gastritis is rarely diagnosed before surgery .
endoscopy of the affected esophagus shows diffuse luminal narrowing with poor distensibility and ulcer - like lesions ( 3 ) .
endoscopic ultrasonography ( eus ) findings in previous case reports were diffuse thickening with hypoechoic lesions in the submucosal layer ( 1 , 6 ) . the endoscopic examination of our patient also revealed similar findings of diffuse mucosal fold thickening , a mucosal ulcer in the upper thoracic esophagus , and scattered hemorrhagic patches in gastric mucosa . the reported ct findings of acute phlegmonous esophagitis or gastritis include diffuse esophageal and stomach wall thickening with circumferential intramural low attenuation surrounded by a peripheral enhancing rim .
the intramural low attenuation represents severe inflammation and abscess localized to the submucosa and muscularis layer ( 4 , 5 ) . within the thickened wall ,
contrast - enhanced chest ct in our patient showed findings typical of acute phlegmonous inflammation with simultaneous esophageal and stomach involvement .
the radiographic differential diagnoses included a dissecting intramural hematoma and tubular duplication of esophagus and emphysematous esophagitis or gastritis ( 5 , 7 ) .
however , the clinical symptom of a dissecting intramural hematoma is chest pain with no evidence of infection or inflammation , and patients with tubular duplication are likely to have no symptoms or signs .
the overall mortality of phlegmonous gastritis in a review of 36 reported cases was 42% , and the mortality rates of the 10 patients that underwent surgical resection as compared with the 26 patients treated conservatively were 20% ( 2/10 ) and 50% ( 13/26 ) , respectively ( 6 ) . during the last 50 yr , some reports have described patients with phlegmonous gastritis successfully treated with medical therapy alone .
overall , the mortality rate for patients with medially treated localized disease was 17% , whereas that for diffuse disease was 60% .
thus , antibiotic therapy and surgical drainage are effective treatments for acute phlegmonous esophagitis depending on the clinical situation ( 1 , 3 , 8) . in cases of phlegmonous esophagogastritis ,
protracted conservative treatment result in surgical resection due to the possibilities of esophageal necrosis , esophageal stricture , gastric mucosal atrophy , and complicated peritonitis ( 1 , 8 , 9 ) .
our patient was initially treated with broad spectrum antibiotics and left closed thoracostomy with empyema drainage .
however , surgical intervention was decided upon due to a worsening of his condition , the duration of his clinical symptoms , and radiographic findings , which included a proper ct diagnosis of acute phlegmonous esophagogastritis .
we consider that combined medical treatment and timely surgical intervention played an important role in the cure achieved in our patient , who experienced no major post - operative complications . in conclusion , although acute phlegmonous esophagogastritis is rare and a preoperative diagnosis is difficult , awareness of this disease entity and prompt diagnosis based on typical chest ct findings are major key factors to successful treatment .

Answer:
acute phlegmonous infection of the gastrointestinal tract is characterized by purulent inflammation of the submucosa and muscular layer with sparing of the mucosa .
 the authors report a rare case of acute diffuse phlegmonous esophagogastritis , which was well diagnosed based on the typical chest computed tomographic ( ct ) findings and was successfully treated . a 48-yr - old man presented with left chest pain and dyspnea for three days .
 chest radiograph on admission showed mediastinal widening and bilateral pleural effusion .
 the patient became febrile and the amount of left pleural effusion is increased on follow - up chest radiograph .
 left closed thoracostomy was performed with pus drainage .
 a ct diagnosis of acute phlegmonous esophagogastritis was suggested and a surgery was decided due to worsening of clinical condition of the patient and radiologic findings .
 esophageal myotomies were performed and the submucosal layer was filled with thick , cheesy materials .
 the patient was successfully discharged with no postoperative complication .


Question:
You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
rasmussen 's aneurysm is a less frequently noticed entity usually associated with pulmonary tuberculosis presenting with massive hemoptysis due to involvement of small peripheral pulmonary or bronchial artery by the tubercular cavity or lesion .
involvement of a large central pulmonary artery by metastatic mediastinal nodal lesions is unreported so far . despite the large size ,
a 65-year - old male of primary squamous cell carcinoma left buccal mucosa treated by left composite resection , and modified radical neck dissection 8 months back .
postsurgery local radiation with 25 fractions of 2 grey ( gy ) each completed just 4 months before , presented with generalized weakness and pain right hip region .
there was no history of fall , fever , loss of weight or bleeding from any site .
clinical examination revealed no evidence of disease at the local site and no palpable masses anywhere in the body and there was no neurological deficit .
hematological , bio chemical and metabolic parameters were within normal limits , except mild hypo chromic normocytic anemia .
initial imaging with magnetic resonance imaging of lumbo sacral spine revealed t1 hypointense and t2 hyperintense signal intensities in right sacral ala and iliac bone lesions suggestive of metastatic lesions .
patient was subjected to fluorine 18-fluoro deoxy glucose positron emission tomography / computerized tomography ( f18-fdg ) for restaging and further evaluation .
the primary site of left buccal region showed postoperative status with no morphological or metabolic abnormality .
there was a metabolically active enhancing nodular mass lesion on the dorsum of the tongue measuring 30  19 mm with a standardized uptake value maximum ( suv max ) of 5.77 [ figure 1a ] , similar nodular deposit in the cervical nuchal muscle measuring 22  21 mm with an suv max of 4.82 [ figure 1b ] .
there were multiple bilateral metabolically active necrotic , nodular , sub pleural and parenchymal pulmonary metastasis with associated mild degree pneumothorax [ figure 2 ] .
mediastinum showed multiple metabolically active enlarged lymphadenopathy encompassing bilateral hilar , sub aortic , and para aortic lymphadenopathy which also showed conglomeration and central necrosis .
interestingly there was a large contrast filled cavitary area measuring 66.6  54.8  72.6 mm seen amidst the necrotic lymph nodal mass , devoid of any fdg avidity [ figure 3 ] . on close scrutiny
the radiographic contrast collection was traceable up to one of the adjoining first order branch of left pulmonary artery [ figure 4 ] .
there were multiple metabolically active mixed lytic sclerotic disseminated skeletal metastasis as well [ figure 5 ] . due to his poor physical condition and the extensive disease load .
small asymptomatic unilateral pneumothorax requiring no intervention and the large extravasated contrast being restricted within the confines of the cavitating nodal metastasis explaining the stark absence of hemoptysis , patient was managed conservatively without any active intervention shifting from a curative to palliative intent .
( a ) metabolically active enhancing nodular mass lesion on the dorsum of the tongue ( dotted arrow ) .
( b ) metabolically active nodular deposit in the cervical nuchal muscle ( thick arrow ) axial positron emission tomography / computerized tomography images of chest showing multiple bilateral metabolically active sub pleural and parenchymal pulmonary metastasis ( arrows ) with associated left sided pneumothorax ( dotted arrow ) axial positron emission tomography / computed tomography images of chest showing multiple metabolically active enlarged mediastinal lymphadenopathy with conglomeration and central necrosis ( arrows ) and a contrast filled cavitary area amidst the necrotic lymph nodal mass devoid of any fluoro deoxy glucose avidity ( dotted arrow ) high resolution axial and coronal computerized tomography chest showing the radiographic contrast collection traceable up to one of the adjoining first order branch of left pulmonary artery ( arrow ) maximum intensity projection and coronal positron emission tomography/ computerized tomography images revealing multiple metabolically active mixed lytic sclerotic disseminated skeletal metastasis ( arrows )
erosive pseudo aneurysm of small caliber pulmonary arterial branch caused by an adjoining infiltrating pulmonary lesion is termed as rasmussen aneurysm .
fritz waldemar rasmussen a 19-century danish physician first described the occurrence of dilation of the pulmonary artery in a tuberculous cavity , rupture of which causes hemorrhage and hemoptysis , often massive and life threatening .
other documented causes are atherosclerosis , bronchiectasis , sarcoidosis , trauma , postcardiac catheterization and postnecrotizing pneumonias .
pathogenesis implicated is the progressive weakening of pulmonary arterial wall adventitia and media by granulation tissue , resulting in thinning of the arterial wall and formation of pseudoaneurysm .
the distribution is usually peripheral and beyond the branches of main pulmonary arteries . in the present era of selective catheter angiography , the entity of rasmussen 's aneurysm
is a retrospective detection encountered while addressing suspected bronchial artery erosion being the cause of massive , intractable and life - threatening hemoptysis .
angiographic intervention is warranted to unearth the source of bleeding and simultaneously attempt to embolize the bleeding source from rasmussen 's transformed culprit artery .
our patient had extensive metastasis to skeleton , lungs , muscles , tongue and mediastinal adenopathy with significant necrosis .
one of the aggressive and necrotizing lymphnodal mass has eroded the adjoining pulmonary artery branch , in this case a major branch vessel unlike smaller vessels usually seen in tuberculosis cavities .
the leaked out blood was contained within the necrotic lymph nodal mass which explains the absence of any revealed hemoptysis and a possible emergency bleeding situation despite the large sized extravasation .
conventional sites of aneurysm are peripheral and beyond the branches of main pulmonary arteries , however it was central in this case and involved a larger central pulmonary arterial branch .
reported cases of rasmussen 's aneurysm are the result of infective and chronic tuberculous cavity eroding the adjoining small caliber bronchial / pulmonary artery and none by an aggressive metastatic necrotic nodal mass .
the case also highlights the aggressive , extensive and erosive nature of squamous cell carcinoma metastasis .
rasmussen 's aneurysm is a rare sequel of pulmonary tuberculosis presenting with massive hemoptysis usually involving a small peripheral pulmonary or bronchial artery .
involvement of a large central pulmonary artery by an aggressive necrotizing mediastinal lymph nodal mass is unreported so far .
our case is one such entity of this rarity with walled off collection of a large magnitude contained within the necrotic mass and nonhemoptytic manifestation being an additional associated rarity .

Answer:
the authors report an extremely rare occurrence of a massive aneurysm of a major pulmonary artery branch vessel caused by adjacent necrotizing aggressive squamous cell carcinoma metastatic mediastinal nodes . despite the huge size
 , there was no hemoptysis due to the walling off effect by the necrotic nodes .


Question:
You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
congenital bochdalek hernia ( cbh ) develops as a result of the inappropriate fusion of the pleuroperitoneal fold and septum transversum at the site of the posterolateral lumbocostal trigone at the sixth week of gestation .
this entity was first described by mccauley in 1754 and then by vincent alexander bochdalek in 1848 .
this type of diaphragmatic hernia is considered a perinatal disease that presents a few hours after birth , or in early infancy , and it is associated with significant morbidity and mortality .
cbh in adults is very rare ; it remains asymptomatic until adulthood and generally presents with thoracic and/or abdominal symptoms aggravated in supine position .
we present a case of left - sided congenital bochdalek hernia that remained asymptomatic and was discovered incidentally during secondary cytoreductive surgery for epithelial ovarian cancer ; in this patient , a iatrogenic diaphragmatic defect was found , hyperthermic intraperitoneal chemotherapy ( hipec ) was performed and early postoperative bilateral anterior thalamic infarction developed .
a 46-year - old female patient with a bmi of 25 was referred to our tertiary center ( cerrahpasa medical faculty , gynecological oncology unit ) in august 2016 with the diagnosis of platinum - resistant ovarian cancer .
positron emission tomography and computed tomography ( ct ) revealed implants on the right diaphragmatic surface after first - line adjuvant chemotherapy . she has never had any thoracic or abdominal symptoms and no history of major trauma . initial preoperative evaluation of the patient revealed no significant sign of diaphragmatic hernia .
her physical examination was normal , including chest auscultation sounds and chest x - ray .
thoracic ct did not reveal any abnormal image that could be evaluated as a diaphragmatic hernia .
she was placed in flank position , and , under general anesthesia , laparotomy was performed .
an oval defect with the dimensions of 3  4 cm was seen in the left posterolateral site of the diaphragm ( fig .
the most distal portion of the inferior lobe of the left lung was visible through the defect during inspiration and expiration movements .
drainage chest tubes were inserted bilaterally via the 6th intercostal spaces to avoid leakage of the chemotherapeutic agents across repaired diaphragm and postoperative massive pleural effusion .
the tissue around the congenital left - sided defect was excised circularly and the defect itself was repaired with interrupted nonabsorbable monofilament sutures .
after complete cytoreduction had been achieved , hyperthermic intraperitoneal chemotherapy with doxorubicin 35 mg / m and paclitaxel 175 mg / m for 60 min at 42.5c was delivered .
no leakage via drainage tubes from the thoracic cavity was noted during the procedure . during the surgery ,
the patient was managed by standard monitoring , which involved continuous monitoring of electrocardiography , invasive blood pressure , central venous pressure , pulse oximetry , body temperature and hourly urine output .
arterial samples were drawn at regular periods for the determination of electrolytes , acid base status and hematocrit .
finally , the operation lasted 4 h. at the end of the surgery , the patient remained intubated and was transferred to the intensive care unit for monitoring ongoing resuscitation along with fluid and electrolyte management .
the patient was extubated 10 h after completion of surgery , and was transferred to the service on the 2nd postoperative day .
prophylactic enoxaparin 4,000 iu was started 6 h after surgery . on the 3rd and 4th postoperative day , excessive sleepiness throughout the day and dyspraxia was noted . bilateral anterior thalamic infarction caused by emboli that block the thalamosubthalamic artery
the dose of enoxaparin was changed from 4,000 iu once a day to 800 iu twice a day .
follow - up at 4 months after surgery showed no evidence of recurrence and no symptom regarding thalamic infarct .
cbh generally presents in newborns with severe respiratory failure or in infancy due to herniation and/or strangulation of the abdominal contents .
one of the best studies concerning the incidence of the defect in adults was carried out by mullins et al . , who reviewed 13,138 ct scans .
their study revealed an incidence of 0.17% , with 68% being right - sided defects and 77% of the patients being female .
since the second study summarized symptomatic cases , demographics identified were different than those in asymptomatic ones .
this difference showed that more cases of right - sided cbh in females may remain silent than left - sided cases .
these data were supported by several case reports . nevertheless , in our case , the defect was noted on the left side . also , no herniation of intestinal loops was noted , and the patient has never had any thoracic or abdominal symptom that might be related to diaphragmatic hernia .
diagnosis of the disease might be carried out by chest ct when there are clinically unexplained thoracic and abdominal symptoms .
the chest ct of our patient did not reveal any of the above - mentioned patterns .
there are several cases concerning surgical repair of the defect  both laparoscopic , via laparotomy , and through the thoracic cavity .
we performed upper midline incision for laparotomy , and there was no need for another access to carry out the repair of the diaphragmatic defect .
repair of diaphragmatic defect can be performed by various techniques , using absorbable or nonabsorbable sutures in an interrupted or continuous fashion . from our point of view
, surgeons may choose any of them provided that they are comfortable with the procedure .
the main reason for using bilateral chest tubes was to prevent massive pleural effusion due to hipec .
in addition , intra - abdominal pressure increases during hipec , which may subsequently cause a cephalad shift of the diaphragm to increase peak airway pressures and reduce residual capacity .
chest drains which were inserted prior to hipec reduce the increase in peak airway pressure , and by this way , the length of the intubation period and hospital stay can be decreased .
malignancy itself , hipec , central venous cannulation , the position of the patient 's neck , sudden blood loss and a long duration of the operation were noted as possible risk factors in our case . in conclusion , although congenital bochdalek hernia commonly occurs in the newborn and infancy period , it must not be excluded in the case of unexplained abdominal and/or thoracic symptoms in adults . despite the fact that this kind of rare condition presents with pain , obstruction symptoms or pulmonary symptoms , it can be silent until discovered incidentally .
secondly , cerebral embolism should be suspected in the presence of any neurological symptom in postoperative patients .

Answer:
congenital bochdalek hernia is a defect of the diaphragm and very rare in adults .
 only around 100 cases have been reported in the literature . herein , we present a case with a recurrent ovarian cancer who underwent secondary cytoreductive surgery and hyperthermic intraperitoneal chemotherapy .
 an oval defect with dimensions of 3  4 cm was seen in the left posterolateral site of the diaphragm during surgical exploration .
 in addition , a 6  3 cm iatrogenic right - sided diaphragmatic defect was found and repaired . in the early postoperative period ,
 a bilateral thalamic infarction occurred .


Question:
You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:

 crestal incision placed about 1.5 mm palatal to the greatest bony height with an angulation of 45 with no .
15 bard parker blade [ figure 1 ]
 a vertical releasing incision placed mesially and distally to the crestal incision without disturbing the adjacent teeth papilla and extending about 3 mm labially [ figure 2 ]
 soft tissue reflected to expose the cover screw [ figure 3 ]
 palatal extension of the incision followed closer to the adjacent teeth on both sides , and a release incision made around the palatal portion of the exposed cover screw [ figure 4 ]
 then healing abutment is placed after thoroughly cleaning the soft tissue around internal hex of the implant [ figure 5 ]
 soft tissue approximated with 40 suture material ( vicryl)sutures removal has to be done after 10 daysafter 2 weeks , second stage prosthetic procedure should be carried out .

crestal incision placed about 1.5 mm palatal to the greatest bony height with an angulation of 45 with no .
15 bard parker blade [ figure 1 ]
  a vertical releasing incision placed mesially and distally to the crestal incision without disturbing the adjacent teeth papilla and extending about 3 mm labially [ figure 2 ]
  soft tissue reflected to expose the cover screw [ figure 3 ]
  palatal extension of the incision followed closer to the adjacent teeth on both sides , and a release incision made around the palatal portion of the exposed cover screw [ figure 4 ]
  then healing abutment is placed after thoroughly cleaning the soft tissue around internal hex of the implant [ figure 5 ]
  soft tissue approximated with 40 suture material ( vicryl ) sutures removal has to be done after 10 days after 2 weeks , second stage prosthetic procedure should be carried out . incision and flap outlined ( after reflection )
more importantly it plays an important and crucial role in an esthetic component of a natural dentition .
hence , it is very vital to maintain the integrity of the papilla during second stage implant surgery .
several methods with unique incisions and suturing designs have been proposed to regenerate interdental papilla around implants .
palacci suggested that a full thickness flap be raised from the buccal and palatal side of the implant on the ridge and rotated 90 to accommodate the interproximal space of the implant .
palatal sliding strip flap  to form papilla between implants and natural dentition in the anterior maxilla .
nemcovsky et al . suggested an u- shaped incision , with opening toward the buccal aspect of the implant site with divergent incisions .
tinti and benfenati reported a ramp mattress suture design , which pulled the buccal flap coronally , to obtain a papilla between two implants .
suggested a split finger surgical method in which three interlacing finger like incisions were made and each of the fingers was sutured over the desired interdental papillary position .
proposed a method for papilla regeneration wherein the healing abutment is buried beneath the gingival flap to produce a dead space with expectation of the space being filled by the soft tissue . even though these procedures provided papillary height , the results were not predictable .
various factors were involved in the success of any papilla regeneration procedures , such as preservation of blood supply , prevention of scar formation , and more importantly ideal placement of the implant into the bone .
this new and innovative surgical technique provided significantly excellent results compared to the conventional mid - crestal technique [ figures 6 and 7 ] . in this case report , in order to overcome the limitations of above - mentioned techniques a novel window technique was followed to regenerate papilla around implants during second stage surgery prior to prosthetic restoration . unlike most other procedures mentioned above , this technique avoided the labial papilla on the adjacent teeth and involved wholly the palatal papilla , which is considered to be the key element in the success of this technique .
moreover , there is no cross incisions on to the papilla , which may lead to , disturbed wound healing and scar formation .
above all avoiding more invasive surgery is considered one of the best methods of soft tissue regeneration , which is being incorporated in this technique .
the major advantages of this technique , when compared with earlier ones , are minimal invasive incision , less postoperative discomfort , and excellent esthetic and emergence profile obtained
. the aim of any soft tissue procedure should be to obtain a resilient and scar less soft tissue .
this can be obtained with atraumatic tissue handling , minimal tension during approximation , adequate vascularity , adequate hydration , and expedient surgical procedures that do not compromise blood supply .
this case report shows the excellent results following the above requisites to obtain esthetic soft tissue profile .
the patients were followed for 2 years at regular intervals and still the esthetic results obtained during the surgery and after 2 years were the same [ figure 8 ] . with above considerations with respect to follow - up and esthetic component , this technique provided the required and desired results .
in order to obtain esthetic papillary height and tissue integrity around implants proper and meticulous implant positioning is needed .
being a long term follow - up report this technique can be considered as a simple , minimal invasive procedure , which can be followed during 2 stage surgery .

Answer:
reconstructing predictable and esthetic papilla is the most complex and challenging aspect of implant dentistry . to obtain an esthetic and predictable gingival architecture and implant restoration ,
 interdental papilla plays an important role .
 the main objective of the surgeon during the second stage of implant treatment should be the creation of interdental papilla prior to prosthetic restoration .
 the aim of this case report was to demonstrate a novel window technique for developing predictable and esthetic papilla around dental implants , which was followed for 2 years with excellent esthetic results .


Question:
You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
septic arthritis of the shoulder is uncommon in adults . it is a surgical emergency as joint destruction occurs rapidly and can lead to significant morbidity and mortality .
a 43 years old male came to our outpatient department with complaints of pain and stiffness of his left shoulder . on examination , his shoulder movements were severely restricted .
further evaluation with mri revealed septic arthritis of left gleno - humeral joint for which emergency arthroscopic debridement was done .
septic arthritis of shoulder may not present with classical clinical features . hence , a through clinical and radiological evaluation will help us prognosticate and treat accordingly thereby preventing complications like septic shock , osteomyelitis .
patients with septic arthritis usually develop moderate to severe joint pain , warmth , tenderness , effusion , restricted active and passive motion , and sometimes redness .
we report an unusual presentation of shoulder septic arthritis in a 43 years old man with no other clinical signs and symptoms of classical septic arthritis .
a 43-year - old man presented to the orthopaedic outpatient clinic with 2 months history of pain and limited range of motion in his left shoulder .
his pain was insidious in onset , mild to moderate in intensity , aggravated by activities and associated with moderate rest and night pain .
patient was diagnosed as frozen shoulder at an outside facility and had been given intraarticular depomedrol 40 mg injection for the same 40 days ago with no improvement in his symptoms .
he is diabetic and has liver cirrhosis and is on treatment . on physical examination ,
the skin colour and temperature of the left shoulder were normal , but the shoulder was tender to touch over the anterior joint line .
mri was obtained [ fig 2 ] which showed extraosseous soft tissue enhancements around left shoulder with soft tissue abscess in inter muscular planes of supraspinatous , infraspinatous , subscapularis .
blood test revealed normal white cell count with normal differential count , crp-13.4 mg / l ( normal<5.0 mg
the erythrocyte sedimentation rate was raised , at 88 mm / hour ( normal range , 0 - 20 mm / hour ) aspiration of shoulder joint was performed and fluid was sent for aerobic and anaerobic culture , afb staining , mycobacterium culture , and mycobacterium genetic testing .
arthroscopic lavage of the joint was done and articular fluid sent for repeat aerobic and anaerobic culture .
joint visualization was markedly limited because of severe inflammation and fibrinous changes of the joint .
the articular cartilages of glenoid and humeral head were completely eroded down to the bone .
susceptibility of the isolate was determined with the disk diffusion method and it was susceptible only to colistin .
3 ) fibrocollagenous and fibrovascular inflammed connective tissue containing proliferated blood vessels and perivascular mixed inflammatory cells and lymphoplasmacytoid cells .
based on preoperative and intraoperative culture report , a definitive diagnosis of polymicrobial septic arthritis of the shoulder was established and patient was treated with combination antimicrobial treatment .
our patient had muted inflammatory response probably due to immunocompromised state ( cirrhosis and diabetes ) which is not uncommon .
most often it is hematogenous seeding of shoulder joint , however it can also happen after intraarticular steroid injections .
septic arthritis of the shoulder is more common in immunocompromised patients and intravenous drug abusers . in this case report , the patient had atypical clinical symptoms and is immunocompromised and his primary source of infection seems to be hematogenous .
our experience with this patient highlights the importance of maintaining high index of suspicion for septic arthritis in immunocompromised patients presenting with atypical shoulder pain associated with stiffness . in the setting of suspected septic arthritis ,
our initial pre - investigation diagnosis was atypical shoulder pain and stiffness of non specific etiology in an immunocompromised patient and infection was part of the differential diagnosis not the only diagnosis .
esenwein et al in his report highlighted the importance of early intervention to prevent chondral damage , osteomyelitis and also to prevent systemic spread .
various authors have highlighted the importance of early diagnosis and management of septic arthritis failing which could lead to osteomyelitis and septic shock . in our patient
, the diagnosis was delayed due to atypical presentation and over reliance on clinical findings at an outside center .
we strongly recommend early imaging studies in immunocompromised patients presenting with shoulder pain and practitioners should avoid loosely diagnosing as shoulder pain with associated stiffness as frozen shoulders .
klinger et al . did a retrospective study on 21 patients who underwent surgical treatment for septic arthritis of the shoulder joint between 2000 and 2007 , and he concluded that patients with symptoms for less than 2 weeks did well with arthroscopic approach and early infection can be managed arthroscopically .
our reports show that arthroscopic washout can give good result even after 2 weeks of clinical symptoms if there is no evidence of osteomyelitis .
septic arthritis of the shoulder is very often due to hematogenous spread and diagnosis is often clinical .
laboratory investigations and imaging studies like mri and usg may be useful in establishing the diagnosis but confirmation is usually by joint aspiration .
patients who are immunocompromised and have insidious onset of moderate to severe pain and which fails to respond to trial of conservative treatment should be subjected to either ultrasound or mri instead of x - ray because very often in these group of patients it is primarily a soft tissue pathology like impingement , rc tear , calcific tendinitis or rarely infections and malignancies .
we recommend that moderate pain of more than 4 weeks duration with severe stiffness in immunocompromised patient ( liver cirrhosis , renal failure , steroid treatment ) should be further evaluated with mri or ultrasound in the setting of normal x - ray and should not be loosely diagnosed as frozen shoulder .
goldenberg in his report emphasized the role of local as well as systemic factors that predispose patients with cirrhosis to gram - negative bacterial joint infections .
malnick also reported a case of spontaneous septic arthritis in a cirhottic patient that was due to e.coli .
our study as well as other studies by goldenberg and malnick highlight the importance of including broad spectrum antibiotics with gram negative cover whilst waiting for final culture sensitivity .
septic arthritis of shoulder may not present with classic clinical features . a through clinical and radiological evaluation should be executed and treatment initiated promptly to prevent complications like septic shock and osteomyelitis .
the case highlights the importance of establishing anatomical and pathological diagnosis using mri in patients with shoulder pain instead of loosely diagnosing them as impingement or frozen shoulder .
the case also challenges the practice of routine shoulder depomedrol steroid injection , in the setting of secondary frozen shoulder , atleast in immunocompromised individuals .
primary idiopathic frozen shoulder is a rare condition and secondary frozen shoulder cases are often due to underlying shoulder pathology .

Answer:
introduction : septic arthritis of the shoulder is uncommon in adults . it is a surgical emergency as joint destruction occurs rapidly and can lead to significant morbidity and mortality .
 accurate diagnosis can be particularly challenging in patients with underlying liver disease .
 mri is a useful adjunct in early detection of atypical causes of shoulder pain.case report : a 43 years old male came to our outpatient department with complaints of pain and stiffness of his left shoulder . on examination ,
 his shoulder movements were severely restricted . further evaluation with mri revealed septic arthritis of left gleno - humeral joint for which emergency arthroscopic debridement was done.conclusion:septic arthritis of shoulder may not present with classical clinical features .
 hence , a through clinical and radiological evaluation will help us prognosticate and treat accordingly thereby preventing complications like septic shock , osteomyelitis .


Question:
You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
approximately 30% of individuals over 65 yr of age fall at least once a year ( tinetti , 2003 ) .
falling is a major public health and medical problem that can cause serious injuries including fracture , brain injury , and even death . as aging progresses , muscle mass , muscle strength , and joint range decrease and strides narrow as walking speed declines .
stimulus response time and nerve conduction velocity decrease owing to changes in the nervous system , which leads to reduced balance ability .
this decline in physical function reduces lower extremity strength , balance , and flexibility , thereby causing frequent falling during walking ( huh et al . , 2010 ; jeoung , 2014 ; kressing et al . ,
in korea , 21.441.6% of elderly patients receiving home care and 30.3% of elderly patients in nursing homes who have experienced falls ( gu et al . , 2006 ) , in who over 65
yr elderly , falling were higher prevalence than other elderly disease ( kim and lee , 2006 ) . of community - dwelling elderly persons ,
43% reported being fearful of falling , while 44% reported activity restrictions ( robertson et al . , 2002 ) .
almost half of older adults transitioning to frailty had a fear of falling ( kressing et al . , 2001 ) .
fear of falling is not only the immediate result of falls but also a risk factor for falls which creates a vicious cycle between falls and fear of falling .
various complex health problems arise in 50% of the elderly who have experienced falls ; 10% of them require medical treatment and 5% experience fracture .
since 50% of the elderly individuals who are admitted to the hospital for fall - related injuries die within 1 yr , falling is a major cause of morbidity and mortality in the elderly ( tinetti and powell . , 1993 ) . since falling induces pain , restricts activities , and disables independent living , fear of falling and the restriction of social activities due to falling greatly reduce well - being and quality of life . as such
, falling not only leads to physical damage in the elderly but can create serious problems for social well - being ; therefore , studies on fall prevention and intervention are required .
recent research implicates fear of falling as a contributor to physical dependence among elderly persons ( tinetti and powell . , 1993 ) , while other studies supported the close association among exercise , physical performance , and fear of falling ( li et al . , 2005 ) .
the risk of falling can reportedly be reduced for those who exercise regularly , but few studies have examined its correlation with physical fitness . the purpose of this study was to examine the correlation between physical fitness and falling fears in the elderly .
a total of 173 elderly women who were 6585 yr old were recruited from a welfare center in inchon city .
all potential participants underwent a comprehensive explanation of the proposed study , its benefits and inherent risks , and the expected time commitment .
medical information ( health status and medications ) was obtained from participants using a questionnaire .
the subjects were excluded if they were not able to walk without a cane or other assistive device or had known conditions and musculoskeletal problems limiting their safe participation in this study .
the physical fitness test for seniors was developed by roberta & jessie and included a 6-min walk test , grip strength , 30-sec arm curl test , 30-sec chair stand test , back scratch and chair sit and reach test , 8-foot up and go , unipedal stance , and body mass index .
this study approached fear of falling in two ways : ( 1 ) direct questioning focused on perceptive fear of falling ; and ( 2 ) the korean version of the fall efficacy scale - international ( kfes - i ) to measure the confidence of avoiding falling during daily activities using the level of concern about falling .
the kfes - i has 16 items , each of which is scored from one to four for a total score of 1664 . according to the cut point suggested by delbaere et al .
( 2004 ) , we considered patients with a score 23 as having a higher level of concern over falling
. statistical analysis was performed using spss for windows version 21 ( ibm spss inc . ,
a correlation analysis was conducted to examine the correlation between fall efficacy and physical fitness factors , and the correlated physical fitness factors were divided into quartiles to analyze the differences between groups . to investigate the differences in fall efficacy between physical fitness items , one - way analysis of variance ( anova ) was performed .
a total of 173 elderly women who were 6585 yr old were recruited from a welfare center in inchon city .
all potential participants underwent a comprehensive explanation of the proposed study , its benefits and inherent risks , and the expected time commitment .
medical information ( health status and medications ) was obtained from participants using a questionnaire .
the subjects were excluded if they were not able to walk without a cane or other assistive device or had known conditions and musculoskeletal problems limiting their safe participation in this study .
the physical fitness test for seniors was developed by roberta & jessie and included a 6-min walk test , grip strength , 30-sec arm curl test , 30-sec chair stand test , back scratch and chair sit and reach test , 8-foot up and go , unipedal stance , and body mass index .
this study approached fear of falling in two ways : ( 1 ) direct questioning focused on perceptive fear of falling ; and ( 2 ) the korean version of the fall efficacy scale - international ( kfes - i ) to measure the confidence of avoiding falling during daily activities using the level of concern about falling .
the kfes - i has 16 items , each of which is scored from one to four for a total score of 1664 . according to the cut point suggested by delbaere et al .
( 2004 ) , we considered patients with a score 23 as having a higher level of concern over falling .
statistical analysis was performed using spss for windows version 21 ( ibm spss inc . ,
a correlation analysis was conducted to examine the correlation between fall efficacy and physical fitness factors , and the correlated physical fitness factors were divided into quartiles to analyze the differences between groups . to investigate the differences in fall efficacy between physical fitness items , one - way analysis of variance ( anova )
there was a significant correlation between 6-min walk , 30-s chair stand test , 30-s arm curl test , chair sit and reach test , back scratch test , and 8-foot up and go test scores , unipedal stance , grip strength , and fall efficacy ( p<0.05 ) ( table 2 ) . the mean fall efficacy was 25.499.4 , higher than the fall efficacy risk score ( < 23 ) .
analysis of fall efficacy after the division of each physical fitness item into quartiles showed that fall efficacy was lower as physical fitness increased . moreover , the group with the highest level of physical fitness ( > 75% ) had the lowest risk of fall efficacy compared to the group with the lowest level of physical fitness ( < 25% ) .
the group with high physical fitness ( > 75% ) according to the 6-min walk , 30-s chair stand test , 30-s arm curl test , and 8-foot up and go test scores and grip strength had lower fall efficacy points than the cut point suggested by delbaere et al .
risk of falling in the elderly includes not only the result of falling itself but also the high chance of injury accompanying falls .
analysis of the correlation between physical performance and fear of falling in this study showed that they have a strong correlation and that fear of falling decreases as physical fitness level increases .
studies have reported a strong correlation between muscle strength and balance with falling ( howland et al . , 1993 ; lawrence et al . ,
that is , balance ability and falling are decided by how the body copes with a sudden postural disturbance in which an individual maintains a correlation between the instant reaction and the balance ability of the upper and lower body ( higuchi et al . , 2004 ; jeoung , 2014 ; walker et al , 1991 ) .
for this reason , muscle strength declines and the incidence of falling becomes more frequent as aging progresses .
the results of this study also verified that muscle strength , cardiovascular endurance , and agility are highly associated with a fear of falling as shown in previous studies .
therefore , a regular exercise program that can enhance muscle strength , muscle endurance , cardiovascular endurance , and agility should be emphasized .

Answer:
the fear of falling is a common psychological consequence of falling , especially for elderly individuals .
 fear of falling can lead to activity restriction and medical problems .
 the primary purpose of this study was to examine the correlation between fall efficacy and physical fitness factors in elderly women .
 we assessed physical fitness factors and investigated the korean version of the fall efficacy scale - international ( kfes - i ) in 173 participants .
 we investigated the correlation between physical fitness factors and fall efficacy .
 when the subjects were divided into four groups according to physical fitness level , subjects with high 6-m walk , 30-s chair stand test , 30-s arm curl test , chair sit and reach test , 8-foot up and go test scores and high grip strength had low fall efficacy .
 physical fitness factors were strongly associated with decreased fall fear , suggesting that physical fitness improvements play an important role in preventing or reducing the fear of falling .


Question:
You will be presented with the full text of a biomedical research paper. Please write an abstract for this paper. Your response should include the abstract and no additional text.

Paper text:
to demonstrate the usefulness of enhanced depth imaging optical coherence tomography ( edi - oct ) in investigating choroidal lesions inaccessible to ultrasound sonography .
in a 60-year - old woman with an asymptomatic choroidal nevus , normal oct was used to observe the macula and edi - oct to image the choroidal nevus that was inaccessible to ultrasound .
the exact location of the lesion in the choroid and the dimensions of the nevus were measured .
the lesion was located in the superior macula , and the nevus was homogeneous in its reflectivity .
we observed a thickened choroid delineated by the shadow cone behind it , measuring 1,376  325 m in the larger vertical cut and 1,220  325 m in the larger horizontal cut in an image with a 1:1 pixel mapping and automatic zoom .
edi - oct appears to be an excellent technique for measuring choroidal nevi and all choroidal lesions accessible to oct imaging by depicting their exact location in the choroid , their dimensions , and their demarcation from the surrounding healthy tissue , thus allowing for a more efficient and accurate follow - up .
choroidal nevus is the most common tumor of the ocular fundus , present in 7% of the white population [ 1 , 2 ] . despite its benign nature
, it presents a risk of visual loss and visual field loss , and can rarely transform into malignant melanoma .
optical coherence tomography ( oct ) and ultrasonography have been used for imaging choroidal nevi . recently
, enhanced depth imaging oct ( edi - oct ) has been used in order to measure choroidal thickness in normal and pathologic eyes [ 3 , 4 ] . here
, we report a case of a flat choroidal nevus inaccessible to ultrasound sonography that was evaluated by edi - oct .
a 60-year - old woman was referred to our department with an asymptomatic choroidal nevus in her left eye . her best - corrected visual acuity was 20/20 in both eyes . slit lamp and fundus examinations of the right eye were normal . in the left eye , the anterior segment was normal ; however , on fundoscopy a choroidal nevus located in the superior macula was observed ( fig .
spectral - domain ( sd ) oct ( heidelberg engineering , heidelberg , germany ) revealed normal foveal thickness ( fig .
2 ) . the flat nevus was inaccessible to ultrasound sonography , and edi - oct was used to image its posterior surface ( fig .
edi - oct is a new technique that consists of positioning a heidelberg sd - oct close enough to the eye in order to obtain an inverted image , averaged for 100 scans .
the advantage of this technique is that the sensitivity of the imaging in deeper tissue layers is increased , and thus the obtained measurements are more accurate .
we employed this technique to image the location of the nevus in the choroid and obtain its dimensions as a reference measure for the follow - up examination ( fig .
3 ) . heidelberg sd - oct provides an exact correlation between the oct image and the infrared photograph . as infrared light
is absorbed by melanin , the nevus appears brighter . in the edi - oct image
, the lesion appears homogeneous and hyperreflective at the level of the large choroidal vessels , masking the underlying choroidal vasculature .
the choroidal thickness at the level of the nevus appears greater than the neighbor choroid ( fig .
the diameter of the nevus was calculated based on the presence of a shadow cone created by the lesion 's lateral borders .
the choroidal thickness was measured based on the hyperreflectivity between the bruch 's membrane and the beginning of the shadow cone ( fig .
the choroid measured 1,220  325 m in the larger horizontal cut and 1,376  325 m in the larger vertical cut in an image with a 1:1 pixel mapping and automatic zoom ( fig .
edi - oct appears to be an excellent technique for evaluating flat choroidal nevi that are inaccessible to ultrasound sonography and accessible to oct imaging , displaying simultaneously the lesion and the retinal changes .
it is a reproducible examination that allows depiction of the exact location of the nevi in the choroid , their dimensions and their demarcation from the surrounding healthy tissue . to date , the software available for sd - oct does not allow for objective measures .
the subjective measures obtained are useful upon comparison with the follow - up images . in order to limit the possibility of bias
, these follow - up images must be obtained and compared with the same sd - oct machine .
we believe that this technique is clinically useful and , together with color fundus photography , can provide a more efficient and accurate follow - up of choroidal nevi .

Answer:
purposeto demonstrate the usefulness of enhanced depth imaging optical coherence tomography ( edi - oct ) in investigating choroidal lesions inaccessible to ultrasound sonography.methodsin a 60-year - old woman with an asymptomatic choroidal nevus , normal oct was used to observe the macula and edi - oct to image the choroidal nevus that was inaccessible to ultrasound .
 the exact location of the lesion in the choroid and the dimensions of the nevus were measured.resultsthe lesion was located in the superior macula , and the nevus was homogeneous in its reflectivity .
 we observed a thickened choroid delineated by the shadow cone behind it , measuring 1,376  325 m in the larger vertical cut and 1,220  325 m in the larger horizontal cut in an image with a 1:1 pixel mapping and automatic zoom .
 the macular profile and thickness were both normal.conclusionsedi-oct appears to be an excellent technique for measuring choroidal nevi and all choroidal lesions accessible to oct imaging by depicting their exact location in the choroid , their dimensions , and their demarcation from the surrounding healthy tissue , thus allowing for a more efficient and accurate follow - up .