title: Time course of hydronephrotic changes following unilateral pyeloplasty.
abstract: OBJECTIVE
  The temporal pattern of hydronephrotic change following pyeloplasty has not been well defined. To address this issue, 23 years of postpyeloplasty follow-up data from a single surgeon were analyzed.
  
  
  METHODS
  Records of dismembered pyeloplasty from 1986 to 2004 were retrospectively reviewed. Ultrasound follow-ups were conducted at 3-6-month intervals after surgery for up to 3 years, and were then extended to either annually or biannually until the completion of puberty. Overall outcome of hydronephrosis (HN), timing of initial improvement and normalization were determined. Factors associated with these changes were examined.
  
  
  RESULTS
  Of 215 patients who completed follow-up of at least 5 years, about 80% experienced either normalization or improvement. Once they had shown improvement of HN during follow-up, no recurrence was observed. The median time for recognition of initial improvement and normalization of HN was 8 months and 41 months after surgery, respectively. Multivariate analysis revealed that the presence of immediate postoperative obstruction was a negative factor for initial improvement. Symptomatic presentation and no initial improvement until 6 months after pyeloplasty turned out to be negative factors for normalization.
  
  
  CONCLUSIONS
  The results confirm the excellent long-term outcome of pyeloplasty, and highlight the importance of frequent ultrasound until initial improvement of HN, when subsequent ultrasound follow-ups may be safely omitted to focus on follow-up of renal function, proteinuria and hypertension.
authors.affiliation: Department of Urology, Seoul National University, Republic of Korea. Electronic address: urodori9@snu.ac.kr.
authors.forename: Kwanjin
authors.initials: K
authors.lastname: Park
authors.forename: Minki
authors.initials: M
authors.lastname: Baek
authors.forename: Sung Yong
authors.initials: SY
authors.lastname: Cho
authors.forename: Hwang
authors.initials: H
authors.lastname: Choi
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006869:Hydronephrosis / Q000150:complications / Q000000981:diagnostic imaging / Q000601:surgery; D006977:Hypertension, Renal / Q000000981:diagnostic imaging / Q000209:etiology / Q000601:surgery; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D015999:Multivariate Analysis; D011507:Proteinuria / Q000000981:diagnostic imaging / Q000209:etiology / Q000601:surgery; D012189:Retrospective Studies; D055502:Secondary Prevention; D016896:Treatment Outcome; D014463:Ultrasonography; D014517:Ureteral Obstruction / Q000000981:diagnostic imaging / Q000209:etiology / Q000601:surgery; D013520:Urologic Surgical Procedures; D055815:Young Adult
keywords: Follow-up study; Hydronephrosis; Pyeloplasty; Ultrasonography