Table 3.
Summary of clinical studies using sphincteric BoNT-A injections for patients with Fowler’s syndrome (FS) and poor relaxation of the external urethral sphincter (PRES).
| Author (Year) | Sex (No.) | Disease (No.) | Injection Method and Dose | UDS Improvements | Clinical Improvements (Events/Total Cases) |
Adverse Events (Events/Total Cases) |
Effective Duration |
|---|---|---|---|---|---|---|---|
| Studies regarding BoNT-A injection in FS | |||||||
| Fowler et al. (1992) [79] | F (6) | FS (6) | Transperineal 200U BoNT-A | NA | No women restored normal micturition reflex | SUI (1/6) | NA |
| Liao and Kuo (2007) [55] | M (112) F (88) |
FS (2) a Non-FS (198) |
Transperineal 100U Botox | MUP | No improvement in voiding efficiency | Nil | NA |
| Panicker et al. (2016) [80] | F (10) | FS (10) | Transperineal 1 mL 2% lidocaine followed by 100U Botox | PVR, Qmax, MUP | IPSS improvement (8/10) Stopped CIC (7/10) |
Nil | 12–14 weeks |
| Studies regarding BoNT-A injection in PRES | |||||||
| Kuo (2003) [48] | M (48) F (55) |
PRES (19) Non-PRES (84) |
Transurethral (M) or periurethral (F) 100U Botox | PVR | Excellent outcome (8/19) Improved outcome (7/19) |
NA b | 2–6 months |
| Liao and Kuo (2007) [55] | M (112) F (88) |
PRES (23) Non-PRES (177) |
Transurethral (M) or periurethral (F) 100U Botox | NA | Excellent outcome (12/23) Improved outcome (10/23) |
Nil | NA |
| Kuo (2007) [25] | M (22) F (5) |
PRES (5) Non-PRES (22) |
Transurethral (M) or periurethral (F) 50-100U Botox | PVR, Pdet, Qmax | Significant voiding and QoL improvement b | Nil | NA b |
| Lee et al. (2019) [81] | M or F (155) | PRES (17) Non-PRES (138) |
Transurethral (M) or periurethral (F) 100U Botox | Voiding efficiency | Improved voiding efficiency and global response assessment (8/17) | NA b | NA |
BoNT-A = Botulinum toxin A; CIC = Clean intermittent catheterization; F = Female; FS = Fowler’s syndrome; IPSS = international prostate symptom score; M = Male; MUP = Maximal urethral pressure; NA = data not accessible from the study; Nil = none; No. = number; Pdet = Detrusor contraction pressure; PRES = Poor relaxation of the external urethral sphincter; PVR = Post-void residual urine volume; Qmax = Maximal flow rate; QoL = Quality of life index; SUI = Stress urinary incontinence; UDS = Urodynamic study. None of these studies were randomized or controlled. Sphincteric injections were given with preparation other than typical BoNT-A commercial form including Botox or Disport denoted as “BoNT-A”. a The subjects enrolled were not typical FS patients. They had a very high baseline MUP but did not have typical patterns of FS presented in a concentric needle electromyographic study. b Data were analyzed using combined groups. Individual results for specific disease groups were not available.