title: The bell-shaped nitinol prostatic stent in the treatment of lower urinary tract symptoms: experience in 108 patients.
abstract: OBJECTIVE
  To assess the efficacy, safety, and durability of the bell-shaped nitinol prostatic stent in the treatment of moderate to severe lower urinary tract symptoms caused by benign prostatic enlargement in otherwise healthy patients.
  
  
  METHODS
  Stents were inserted in an outpatient setting under local anaesthesia. Assessments included maximum urinary flow (Qmax), postvoid residual (PVR) urine volume, International Prostate Symptom Score (IPSS), including quality of life (QoL) item, at baseline and follow-up visits.
  
  
  RESULTS
  108 men were enrolled in the trial. Stents were successfully inserted in 97% of the patients. Spontaneous voiding was achieved in all patients. After one month Qmax (+3.7 ml/s), PVR (-99 ml), IPSS (-12) and QoL (-1.7) all showed statistically significant improvements compared to baseline. Substantial improvements, however, were maintained for only one to two months. The main complications were haematuria (19%), urge incontinence (22%), and migration (15%). The median indwelling time was 105 days. The main reason for removal of stents was worsening of symptoms, which might be attributable to the tilting of stents within the prostatic urethra, found upon removal.
  
  
  CONCLUSIONS
  Insertion of the bell-shaped nitinol prostatic stent temporarily improves voiding parameters and symptom scores. Because of the limited durability, however, the bell-shaped prostatic stent is not suitable for clinical practice.
authors.affiliation: Department of Urology, Academic Medical Center, University of Amsterdam, the Netherlands. M.M.vanDijk@amc.uva.nl
authors.forename: M M
authors.initials: MM
authors.lastname: van Dijk
authors.forename: C A
authors.initials: CA
authors.lastname: Mochtar
authors.forename: H
authors.initials: H
authors.lastname: Wijkstra
authors.forename: M P
authors.initials: MP
authors.lastname: Laguna
authors.forename: J J M C H
authors.initials: JJ
authors.lastname: de la Rosette
mesh_terms: D000368:Aged; D000497:Alloys; D020878:Device Removal; D004869:Equipment Safety; D005500:Follow-Up Studies; D005548:Foreign-Body Migration / Q000209:etiology / Q000503:physiopathology; D006417:Hematuria / Q000209:etiology / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011474:Prosthesis Design; D011788:Quality of Life; D012720:Severity of Illness Index; D015607:Stents / Q000009:adverse effects; D016019:Survival Analysis; D013997:Time Factors; D016896:Treatment Outcome; D014549:Urinary Incontinence / Q000209:etiology / Q000503:physiopathology; D014554:Urination; D014570:Urologic Diseases / Q000503:physiopathology / Q000628:therapy*; D013521:Urologic Surgical Procedures, Male / Q000379:methods*
chemical_list: D000497:Alloys; C013616:nitinol