title: Simple maneuvers to reduce the incidence of false-negative findings for contralateral patent processus vaginalis during laparoscopic hernia repair in children: a comparative study between 2 cohorts.
abstract: BACKGROUND
  Transumbilical or transinguinal laparoscopic evaluation for contralateral patent processus vaginalis (CPPV) is commonly performed during laparoscopic or open hernia repair in children but may occasionally give false-negative findings.
  
  
  METHODS
  A retrospective study was conducted to compare 2 cohorts of children who underwent laparoscopic repair for clinically demonstrated unilateral inguinal hernia and evaluation for CPPV by transumbilical laparoscopy during the study periods of 2004 to 2007 (cohort 1) and 2008 to 2011 (cohort 2). Cohort 1 was a known historical cohort with CPPV being evaluated by laparoscopic inspection alone, whereas additional maneuvers were adopted in cohort 2.
  
  
  RESULTS
  There were 395 and 564 patients in cohorts 1 and 2, respectively. There was no difference between the 2 cohorts in age of patients, sex distribution, laterality of clinically demonstrated inguinal hernia, and follow-up period at the time of data collection. More CPPV were diagnosed in cohort 2 than cohort 1(36.2% vs 25.8%; P < .01). 4 children (1.4%) developed metachronous inguinal hernia following negative laparoscopic evaluation for CPPV in cohort 1 compared with none from cohort 2 at a similar median follow-up period (P < .05).
  
  
  CONCLUSIONS
  The additional maneuvers appear to be superior to laparoscopic inspection alone to evaluate CPPV during laparoscopic hernia repair in children.
authors.affiliation: Division of Paediatric Surgery and Paediatric Urology, Department of Surgery, Prince of Wales Hospital, Shatin, NT, The Chinese University of Hong Kong, Hong Kong, China. pyhtam@surgery.cuhk.edu.hk
authors.forename: Yuk Him
authors.initials: YH
authors.lastname: Tam
authors.forename: Yuen Shan
authors.initials: YS
authors.lastname: Wong
authors.forename: Kin Wai
authors.initials: KW
authors.lastname: Chan
authors.forename: Kristine Kit Yi
authors.initials: KK
authors.lastname: Pang
authors.forename: Siu Yan
authors.initials: SY
authors.lastname: Tsui
authors.forename: Jennifer Wai Cheung
authors.initials: JW
authors.lastname: Mou
authors.forename: Jennifer Dart Yin
authors.initials: JD
authors.lastname: Sihoe
authors.forename: Kim Hung
authors.initials: KH
authors.lastname: Lee
mesh_terms: D016009:Chi-Square Distribution; D002675:Child, Preschool; D005188:False Negative Reactions; D005260:Female; D006552:Hernia, Inguinal / Q000601:surgery*; D059685:Herniorrhaphy / Q000379:methods*; D006801:Humans; D015994:Incidence; D010535:Laparoscopy; D008297:Male; D012189:Retrospective Studies; D016896:Treatment Outcome