title: Parallel second stent placement for refractory ureteral stent malfunction in malignant ureteral obstruction.
abstract: OBJECTIVE
  To review retrospectively the outcome of placement of a parallel second ureteral stent in patients with urinary obstruction secondary to a malignancy.
  
  
  METHODS
  During the period 2005-2008, the medical records of patients with ureteral obstruction from an abdominal malignancy were reviewed. Patients who experienced malfunction of the first ureteral stent subsequently underwent either initial stent exchange (control group) or a parallel second ureteral stent placement. The outcomes of both groups were evaluated in terms of stent function at 1 week, 1 month, and 3 months after the procedure. Several clinical and imaging parameters were also compared between the two groups.
  
  
  RESULTS
  The stent malfunction rate increased more rapidly in the control group. In 1 week, the malfunction rate was 29.4% in the parallel ureteral stent group and 56.7% in the control group. By the end of the third month, the malfunction rate was 72.7% in the parallel ureteral stent group and 100% in the control group. The creatinine level after the procedure was significantly lower in the parallel ureteral stent group (P = 0.004). The incidence of symptomatic urinary tract infection (UTI) was around 30% in both groups (P = 1.000).
  
  
  CONCLUSIONS
  Parallel second ureteral stent placement has a high technical success rate. For terminally ill patients who have a malignancy and an occluded ureteral stent, the technique can effectively relieve obstruction and prolong the function of the stent.
authors.affiliation: Department of Radiology, Taichung Veterans General Hospital, Taichung, Taiwan.
authors.forename: Hung-Chieh
authors.initials: HC
authors.lastname: Chen
authors.forename: Shu-Huei
authors.initials: SH
authors.lastname: Shen
authors.forename: Jia-Hwia
authors.initials: JH
authors.lastname: Wang
authors.forename: William J S
authors.initials: WJ
authors.lastname: Huang
authors.forename: Hsiou-Shan
authors.initials: HS
authors.lastname: Tseng
authors.forename: Po-Yang
authors.initials: PY
authors.lastname: Chang
authors.forename: Cheng-Yen
authors.initials: CY
authors.lastname: Chang
mesh_terms: D000008:Abdominal Neoplasms / Q000150:complications*; D000368:Aged; D000369:Aged, 80 and over; D015415:Biomarkers / Q000097:blood; D016009:Chi-Square Distribution; D003404:Creatinine / Q000097:blood; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010166:Palliative Care; D011474:Prosthesis Design; D011475:Prosthesis Failure; D012189:Retrospective Studies; D018570:Risk Assessment; D012307:Risk Factors; D015607:Stents / Q000009:adverse effects; D013624:Taiwan; D013997:Time Factors; D016896:Treatment Outcome; D014517:Ureteral Obstruction / Q000097:blood / Q000209:etiology / Q000628:therapy*; D014552:Urinary Tract Infections
chemical_list: D015415:Biomarkers; D003404:Creatinine