Trigonal versus extratrigonal botulinum toxin-A: a systematic review and meta-analysis of efficacy and adverse events

Botulinum toxin-A (BoNT-A) is a potent neurotoxin that is an effective treatment for patients with pharmacologically refractory detrusor overactivity (DO). Data assessing the effectiveness of trigonal BoNT-A are limited. This study evaluates adverse events (AEs) and short-term efficacy associated with trigonal and extratrigonal BoNT-A.

Electronic databases (PubMed, EMBASE, and the Cochrane database) were searched for studies comparing trigonal and extratrigonal BoNT-A for DO. Meta-analyses were performed using the random effects model. Outcome measures included incidence of AEs and short-term efficacy.

Six studies describing 258 patients met the inclusion criteria. The meta-analysis did not show significant differences between trigonal and extratrigonal BoNT-A for acute urinary retention (AUR; 4.2 vs 3.7 %; odds ratio [OR]: 1.068, 95 % confidence interval [CI]: 0.239-4.773; P =  0.931) or high post-void residual (PVR; 25.8 vs 22.2 %; OR: 0.979; 95 % CI: 0.459-2.088; P =  0.956). The incidence of urinary tract infection (UTI; 7.5 vs 21.0 %; OR: 0.670; 95 % CI: 0.312-1.439; P =  0.305), haematuria (15.8 vs 25.9 %; OR: 0.547; 95 % CI: 0.264-1.134; P =  0.105) and post-operative muscle weakness (9.2 vs 11.3 %; OR: 0.587; 95 % CI: 0.205-1.680, P =  0.320) was similar in both groups. Finally, differences in short-term cure rates between two study arms were not statistically significant (52.9 vs 56.9 %; OR: 1.438; 95 % CI: 0.448-4.610; P =  0.542).

Although data are limited, no significant differences between trigonal and extratrigonal BoNT-A in terms of AEs and short-term efficacy were observed. Additional randomised controlled trials are required to define optimal injection techniques and sites for administering intra-vesical BoNT-A.