• prostatic hyperplasia;
  • urodynamics;
  • urinary bladder neck obstruction;
  • urethral obstruction;
  • transurethral resection of prostate


  • To assess whether the penile cuff non-invasive urodynamic test serves as an effective diagnostic tool for predicting outcomes prior to disobstructive surgery for men presenting with voiding lower urinary tract symptoms.
  • Patients with proven urodynamic obstruction do better after surgery. The current gold standard, invasive pressure-flow studies, imposes cost, resource demand, discomfort and inconvenience to patients.

Patients and Methods

  • Patients undergoing surgery for prostatic obstruction at Palmerston North Hospital had pre-operative non-invasive urodynamics and completed an International Prostate Symptom Score (IPSS). Catheterised patients were excluded.
  • Two months post-operatively they completed a further IPSS score.
  • An improvement of seven or greater was defined as a clinically successful outcome.
  • Results were compared with the outcome predicted by the nomogram supplied with the urodynamic device.


  • Data was obtained for 62 patients with mean age 70 years (range 49 to 86 years; SD 9 years). Follow-up was complete for all patients.
  • Thirty-eight patients underwent transurethral resection and 24 holmium laser enucleation of the prostate. Mean IPSS score was 21 (range 5 to 35; SD 6) pre-operatively and 11 (range 1 to 31; SD 9) post-operatively.
  • Thirty-five patients were predicted obstructed and 27 not obstructed.
  • 94% of those predicted obstructed had a successful outcome (p < 0.01).
  • 70% predicted as not obstructed did not have a successful outcome after surgery (p < 0.01).


  • The penile cuff test is an exciting adjunct in the decision to proceed to surgery for prostatic obstruction.
  • Patients predicted to be obstructed have an excellent likelihood of a good surgical outcome, yet 30% of those shown not to be obstructed will still do well.
  • Whilst numbers in our study are small, outcomes compare favourably with published results on invasive urodynamic methods.