title: Nomogram to preoperatively predict the probability of requiring epididymovasostomy during vasectomy reversal.
abstract: OBJECTIVE
  Up to 6% of men who undergo vasectomy may later undergo vasectomy reversal. Most men require vasovasostomy but a smaller subset requires epididymovasostomy. Outcomes of epididymovasostomy depend highly on specialized training in microsurgery and, if predicted preoperatively, might warrant referral to a specialist in this field. We created a nomogram based on preoperative patient characteristics to better predict the need for epididymovasostomy.
  
  
  METHODS
  We evaluated patients who underwent primary vasectomy reversal during a 5-year period. Preoperative and intraoperative patient data were collected in a prospectively maintained database. We evaluated the ability of age, years since vasectomy, vasectomy site, epididymal fullness and granuloma presence or absence to preoperatively predict the need for epididymovasostomy in a given patient. The step-down method was used to create a parsimonious model, on which a nomogram was created and assessed for predictive accuracy.
  
  
  RESULTS
  Included in the study were 271 patients with a mean age of 42 years. Patient age was not positively associated with epididymovasostomy. Mean time from vasectomy to reversal was 9.7 years. Time to reversal and a sperm granuloma were selected as important predictors of epididymovasostomy in the final parsimonious model. The nomogram achieved a bias corrected concordance index of 0.74 and it was well calibrated.
  
  
  CONCLUSIONS
  Epididymovasostomy can be preoperatively predicted based on years since vasectomy and a granuloma on physical examination. Urologists can use this nomogram to better inform patients of the potential need for epididymovasostomy and whether specialist referral is needed.
authors.affiliation: Cheseapeake Urology Associates, Baltimore, Maryland 20759, USA.
authors.forename: David M
authors.initials: DM
authors.lastname: Fenig
authors.forename: Michael W
authors.initials: MW
authors.lastname: Kattan
authors.forename: Jesse N
authors.initials: JN
authors.lastname: Mills
authors.forename: Maria
authors.initials: M
authors.lastname: Gisbert
authors.forename: Changhong
authors.initials: C
authors.lastname: Yu
authors.forename: Larry I
authors.initials: LI
authors.lastname: Lipshultz
mesh_terms: D000328:Adult; D004822:Epididymis / Q000601:surgery*; D006801:Humans; D008297:Male; D049451:Nomograms; D011446:Prospective Studies; D013521:Urologic Surgical Procedures, Male / Q000706:statistics & numerical data; D014669:Vasovasostomy / Q000706:statistics & numerical data