To assess the efficacy, defined as improvement of flow rates by more than 50%, improvement in residual volume and scores on the IPSS questionnaire, and safety of urethral sphincter injections of onabotulinumtoxinA in women with a primary disorder of urethral sphincter relaxation, characterised by an elevated urethral pressure profile and specific findings in the urethral sphincter EMG (Fowler's Syndrome).
In this open label pilot institutional review board approved study, ten women) with a primary disorder of urethral sphincter relaxation (elevated urethral pressure profile (UPP), sphincter volume and abnormal EMG) presenting with obstructed voiding (n=5) or in complete urinary retention (n=5) were recruited from a single tertiary referral centre. Baseline symptoms were assessed using the IPSS questionnaire, and urinary flow and post-void residual volume were measured. After 2% lidocaine injection, 100U of onabotulinumtoxintypeA was injected into the striated urethral sphincter, divided on either side, under EMG guidance. Patients were reviewed at week 1, 4 and 10 post-treatment and assessed using the IPSS questionnaire, urinary flow rate and post-void residual volume. The UPP was repeated at week 4.
The mean patient age was 40 years (range 25-65), and mean symptom scores on the IPSS questionnaire improved from 25. 6 to 14. 1, and mean bother score reduced from 6. 1 to 3. 5 at week 10. As compared to a baseline mean flow rate of 8. 12 mls/sec in the women who could void, the flow rate improved to 15. 8 mls/sec at week 10. Four out of five women in complete retention could void spontaneously, with a mean flow rate of 14. 3 mls/sec at week 10. The mean post-void residual volume decreased from 260 mls to 89 mls. The mean static UPP improved from 113 to 90 cmH2 0 at baseline. No serious side effects were reported. Three women with a history of recurrent urinary tract infections developed a urinary tract infection. There were no reports of stress incontinence. Seven out of the ten women opted to return for repeat injections.
This pilot study demonstrates an improvement in patient-reported lower urinary tract symptoms, and objective parameters such as flow rate, post-void residual volume and UPP, ten weeks following urethral sphincter injections of onabotulinumtoxinA. No serious side effects were reported. This treatment could represent a safe outpatient treatment for young women in retention due to a primary disorder of urethral sphincter relaxation. However, a larger study is required to confirm the findings of this pilot study. This article is protected by copyright. All rights reserved.
BJU international. 2015 Oct 05 [Epub ahead of print]
Jalesh N Panicker, Jai H Seth, Shahid Khan, Gwen Gonzales, Collette Haslam, Thomas M Kessler, Clare J Fowler
Department of Uro-Neurology, The National Hospital for Neurology and Neurosurgery and UCL Institute of Neurology, Queen Square, London, WC1N 3BG, United Kingdom. , Department of Uro-Neurology, The National Hospital for Neurology and Neurosurgery and UCL Institute of Neurology, Queen Square, London, WC1N 3BG, United Kingdom. , Department of Uro-Neurology, The National Hospital for Neurology and Neurosurgery and UCL Institute of Neurology, Queen Square, London, WC1N 3BG, United Kingdom. , Department of Uro-Neurology, The National Hospital for Neurology and Neurosurgery and UCL Institute of Neurology, Queen Square, London, WC1N 3BG, United Kingdom. , Department of Uro-Neurology, The National Hospital for Neurology and Neurosurgery and UCL Institute of Neurology, Queen Square, London, WC1N 3BG, United Kingdom. , Neuro-Urology, Spinal Cord Injury Centre, Balgrist University Hospital, University of Zürich, Zürich, Switzerland. , Emeritus Professor, UCL Institute of Neurology, Queen Square, London, WC1N 3BG, United Kingdom.