title: One third of patients with a unilateral palpable undescended testis have a contralateral patent processus.
abstract: OBJECTIVE
  The purpose of this study was to determine the incidence and predictive factors associated with a contralateral patent processus vaginalis in boys with a unilateral palpable undescended testis.
  
  
  METHODS
  We retrospectively reviewed the records of 77 consecutive boys (median age, 15 months; range, 5 months to 17.7 years) who had undergone orchiopexy for a unilateral palpable testis. At inguinal orchiopexy, an 8F feeding tube and a 70° adult cystoscope lens were placed into the peritoneum through the hernia sac, and the contralateral internal ring was inspected. The clinical factors that might predict the presence of a contralateral patent processus vaginalis were determined.
  
  
  RESULTS
  The overall rate of a contralateral patent processus vaginalis was 34% in those with a significant ipsilateral hernia sac. After considering age, side, prematurity, location, and volume of the undescended testis, only the boys with a testis distal to the external ring compared with those with testes lying within the inguinal canal had statistically increased odds of a patent contralateral processus vaginalis (odds ratio, 3.1; 95% confidence interval, 1.08-9.08).
  
  
  CONCLUSIONS
  Approximately one third of boys with a unilateral palpable undescended testis will have a contralateral patent processus vaginalis as determined by transinguinal laparoscopy. The rate is higher (52%) if the undescended testis was distal to the external ring. Both the etiology and significance of this contralateral finding are unknown.
authors.affiliation: Division of Urology, Albany Medical College, Albany, NY 12208, USA. aggarwh@mail.amc.edu
authors.forename: Himanshu
authors.initials: H
authors.lastname: Aggarwal
authors.forename: Barry A
authors.initials: BA
authors.lastname: Kogan
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Feustel
mesh_terms: D000015:Abnormalities, Multiple / Q000175:diagnosis* / Q000453:epidemiology / Q000601:surgery; D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003456:Cryptorchidism / Q000601:surgery*; D006801:Humans; D015994:Incidence; D007223:Infant; D010535:Laparoscopy; D008297:Male; D056126:Orchiopexy; D010537:Peritoneum / Q000002:abnormalities*; D012189:Retrospective Studies