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Paper text:
recurrence and reflux are the 2 main postoperative remote complications of laparoscopic repair of the not - so - rare paraesophageal hernia ( peh ) .
we concluded the same at a free paper presentation of a nonexhaustive nevertheless extensive narrative review of lap - peh repair at the semi - annual meeting ( 2004 ) of the ulster society of gastroenterology , a province - wide organization in northern ireland , uk .
this study was carried out to determine the true incidence of recurrence after lap - peh repair .
the paper search dates were from 1991 ( a year before the start of laparoscopic esophageal practice ) to february 2006 ( the time to collate the data ) .
the national library of medicine ( nlm ) usa was indirectly accessed via its pubmed outlet .
other search sources include embase , cochrane library , hand search , and personal communication .
the key words used for database searches were  laparoscopic ,   paraesophageal ,   hernia ,   recurrence  in combinations .
paper inclusion criteria included primary study , full text article , study involving lap - peh repair , n>25 ( learning curve estimated at 20 to 35 operations ) , > 6-month follow - up , recurrence addressed , and studies in the english language .
studies describing repair of failed nissen fundoplication ( wrap migration ) alone , were excluded .
no scoring system was used for quality grading ( due to the retrospective nature of the participating studies ) .
 section of the papers was considered only if directly explaining the original work . for multiple studies from the same institution ,
only the most recent study or the one with the highest sample power was used , as decided on the basis of consensus .
the data were extracted on to summary sheets for instant access and then entered into microsoft excel 2003 .
the chi - square test was used for pre- and post-2000 comparison , to calculate heterogeneity , and for alternate models ( p value accepted at 0.05 ) .
all were retrospective case series ( level 4 evidence according to oxford centre for evidence - based medicine classification 2001 ) .
the paper by wiechmann ( 2001 ) was counted as a pre-2000 study , because the evaluated data ranged from 1993 through 1997 .
the critical appraisal revealed a general tendency among studies for lack of a clearly stated aim , selection bias ( underpowered ) , performance bias ( evolving technique over the decade ) , detection bias ( very high follow - up loss , deficiency of objective evidence like follow - up esophagogram or ct ) .
there was no significant confounding due to extraneous factors like age , sex , race , and social class .
summary of eligible trials * chi - square test for heterogeneity = 56.99 , df = 12 , p < 0.0001 .
the overall incidence of recurrence from all patients ( n=965 ) was 10.2% ( mean of all studies=12.2% , median=9.4% , iqr=6.5 to18.1 ) , increasing to 14% ( mean of all eligible studies=16.8% , median=16.8% , iqr=8.5 to 21.18 ) among patients followed up ( n=658 ) .
when only the patients with a follow - up esophagogram were considered ( n=301 ) , the true recurrence rate was 25.5% ( mean of all eligible studies=24.7% , median=27.1 , iqr=18.5 to 32.5 ) ( figure 1 ) . among pre-2000 studies , 26/305 recurrences ( 8.5% )
were seen compared with 73/ 660 ( 11% ) in post-2000 studies ( or=1.33 , rr=1.29 , p=0.2 ) ( table 2 ) .
this suggests that the learning curve of the cumulative , all - inclusive experience over a decade is probably not the cause for the lack , or otherwise , of differences in the incidence of recurrence .
detection of recurrence increases with the vigor of search from simple clinical follow - up to follow - up esophagogram ( 10.2% overall to 14% in simple follow - up to 25.5% in esophagogram cohort ) .
comparison of recurrence rate in pre-2000 and post-2000 studies ( 8.52% vs 11% p = 0.27 ) , suggesting lack of improvement over a decade the plotted graphs revealed broad confidence intervals , touching the line of no - effect suggesting an increased chance factor .
clinical heterogeneity existed among plotted individual studies shown by lack of overlap between dot - and - line results ( figure 2 ) .
statistical heterogeneity was shown by chi - square=56.99 with degrees of freedom ( df)=12 ( p<0.0001 ) . for the outcome of interest ( ie , incidence of recurrence ) however , this heterogeneity has been ignored .
 visual  heterogeneity is revealed by lack of overlap between lines . believed to be a combination of selection , performance , and detection bias . for sensitivity analysis ,
2 alternate models were constructed . in the first ( table 3 ) , all patients who had esophageal lengthening ( added collis - nissen procedure ) were isolated and compared with those with conventional repair ( sac excision , cruroplasty , non - collis - nissen fundoplication ) .
it revealed 816 conventional repairs with 99 recurrences ( 12% ) as opposed to 0/149 in the collisnissen group ( p<0.0001 ) .
. recurrence rate for gastroplasty vs non - gastroplasty repairs within the given study ( p < 0.0001 ) in the second ( hypothetical ) model ( table 4 ) , the worst - case scenario ( wcs ) was applied in which all recurrences in a given study were attributed to the collis - nissen group .
the collis - nissen group had an incidence of recurrence of 23/149 ( 15.4% ) ( or=1.77 , rr=1.65 , p=0.03 ) .
sensitivity analysis of studies with esophageal lengthening ( collis or collis - nissen gastroplasty ) using a hypothetical  worst case scenario  ( wcs )
* recurrences in the given study were attributed to the gastroplasty and the recurrence rate determined for gastroplasty vs nongastroplasty repairs within the given study ( 9.3% vs 15.4% , p = 0.03 ) .
however , for this single - issue metaanalysis , no randomized trials were available to address the knowledge gap about the incidence of arguably the most important outcome parameter of lap - peh repair .
the methodological flaws in the participating studies were not sufficient to prevent insight into the recurrence rate . the initial studies dwelled on immediate outcome like injuries , conversion , mortality , and above all length of stay .
the technique has evolved over the last decade of the 20th century , moving from simple reduction and cruroplasty to detailed sac excision , esophageal mobilization , and synthetic or biological mesh implants .
recently ( since 1998 ) esophageal lengthening with procedures like collis gastroplasty coupled with nissen fundoplication have been used .
even with low hierarchy evidence , we thought a meta - analysis was an appropriate means to explore the recurrence issue due to peh being uncommon if not rare . in the participating studies ,
the authors have concentrated on the hiatus repair by suture , synthetic mesh , and biological small intestinal submucosal ( sis ) patches .
the recurrence has not been searched for specifically at the follow - up , and contrast esophagogram has been performed on a symptom - driven basis . because a majority of recurrence is believed to be asymptomatic , detection bias results from lack of specific imaging
. the attrition rate ( loss of follow - up ) has been high among the studies , further contributing to this problem . unless the papers were appraised , it was difficult to determine whether the quoted recurrence rate is from the overall cohort or from the stringently followed up patients .
some authors have used esophageal lengthening , and it appears to confer benefit to the repair .
it is possible that the hiatoplasty may need to be coupled with an esophageal lengthening procedure .
the most important outcome parameter for lap - peh repair has not been quantified thus far .
mandatory ( protocol ) follow - up esophagogram at ( for example ) 1 year would provide a tool for detection of recurrence .
in addition to conventional hiatoplasty , there may be an additional emphasis point in achieving a tension - free secure repair in the form of esophageal lengthening .
background : recurrence and reflux are 2 most important remote complications of lap - paraesophageal hernia ( peh ) repair . 
 however , the extent of recurrence remains unknown . 
 we sought to determine the true incidence of recurrence after lap - peh repair.methods:a meta - analysis was carried out . 
 pubmed , embase , cochrane library , hand search , and personal communication were used to access and appraise studies . 
 the inclusion criteria were full - text papers published from 1991 to date that describe lap - peh repair in > 25 patients , have at least a 6-month follow - up , and address the issue of recurrence .  
 wrap migration  papers were excluded . 
 papers were appraised and the data were isolated on summary sheets . ms office 
 excel 2003 was used to plot the results and represent it in graphs.results:thirteen studies were eligible ( all retrospective case series ) . 
 a total of 965 patients with 99 recurrences were noted . 
 the overall recurrence rate ( in all patients ) was 10.2% and was 14% if only the followed up patients ( n=658/965 ) were considered . 
 however , when patients with objective evidence ( follow - up ba esophagogram ) were used ( 301/965 ) , the  true  recurrence rate was 25.5% ( ie , 1 in 4 recurred ) . 
 the learning curve did not appear to be an issue ( p=0.27 ) . 
 the studies revealed broad 95 ci and touched the line - of - no - effect , thereby increasing the  chance factor .  
 when an alternate model was applied , esophageal lengthening ( by collis - nissen gastroplasty ) revealed a significant protective influence ( p<0.0001).conclusion : the true incidence of lap - peh recurrence is 25.5% . 
 the learning curve is not an adequate explanation . 
 mandatory ( protocol ) follow - up esophagograms at 1 year are essential . 
 two emphasis points in the repair have emerged : hiatoplasty and ( superadded ) esophageal lengthening .