Podium Session 2

5:20 PM - 5:55 PM

Outcomes of Botulinum toxin A in the Treatment of Primary Bladder Neck Obstruction

Dr Christopher IP (1), Dr Henry YAO (1), Dr Sophie PLAGAKIS (2), A/Prof Vincent TSE (2), Prof Lewis CHAN (3), Mr. Johan GANI (1), A/Prof Helen Elizabeth O'Connell (1,3)

(1) Western Health, Footscray, Australia, (2) Concord Repatriation General Hospital, Sydney, Australia , (3) Melbourne Private Hospital, Melbourne, Australia


Primary bladder neck obstruction (PBNO) is a rare non-neurogenic condition that manifests as BOO in the absence of benign prostatic enlargement or pelvic organ prolapse. Treatment varies from pharmacotherapy to surgery. This case series reports on the efficacy of transurethral Botulinum Toxin A (BoNTA) to treat PBNO.


Retrospective data was collected and analysed from May 2011 to 2017 over two centres. All patients diagnosed with PBNO who underwent transurethral injection of BoNTA were examined. We reviewed clinical records that included premorbid symptoms, preoperative urodynamic studies with medical imaging, operation notes, and post procedure responses.


A total of 13 patients the diagnosis of PBNO based on urodynamic studies with fluoroscopy or ultrasound, underwent cystoscopy and injection of BoNTA during this period. The median age was 42 years old (range 28 – 77). Preoperatively, 41.6% (5/12) patients had chronic urinary retention requiring catheterisation, 4 of these performed intermittent self-catheterisation and one requiring suprapubic catheter. 69.2% (9/13) patients had tried alpha blockers prior to their procedure. 91.6% (11/12) patients had not had any prior urological procedures. Diagnosis of PBNO was based on urodynamic findings with either fluoroscopy or ultrasound, except for 1 patient who had negative urethral sphincter electromyography but responded partially to alpha blockers. All patients underwent initial injection of 100 units of BoNTA to the bladder neck and/or detrusor muscle. 75% (9 of 12) had improvement in symptoms, 1 patient was lost to follow up. 6 of 9 patients responded with a 10-point Likert scale questionnaire for overall subjective improvement, the median score for improvement was 8. 8 patients had more than one cycle of BoNTA treatment, 4 went on to have 3 cycles, 2 had 4 cycles, and 2 had 5 cycles. The median wait time between the 1st and 2nd cycle was 7 months (2-22 months), and between the 2nd and 3rd cycle was 9.2 months (6-21months). 3 patients progressed to have definitive bilateral bladder neck incision. There were no significant documented complications from BoNTA.


BoNTA appears effective in the treatment of PBNO in patients who are refractory or intolerant to alpha blockers. It may be a useful prognostic tool prior to definitive bladder neck incision or for those unfit for surgery, however further studies are required to investigate this.