Bladder trabeculation reflects structural bladder remodeling and may influence treatment response in patients with idiopathic overactive bladder (OAB). We hypothesized that increasing trabeculation is associated with reduced symptomatic improvement following intradetrusor botulinum toxin injection, and that the absence of trabeculation (grade 0) identifies a more treatment-responsive phenotype.

A retrospective clinical study was conducted in patients with idiopathic (non-neurogenic) OAB treated with intradetrusor botulinum toxin between December 2024 and December 2025. Trabeculation was graded from 0 to 3 using cystoscopic evaluation according to a previously described classification system (1). Symptom severity was assessed using OAB total score and OAB quality of life (OAB-QoL).

Treatment response was defined as the change between preoperative and postoperative scores (Δ = pre − post), with positive values indicating improvement. Associations between trabeculation grade and symptom changes were analyzed using Spearman correlation. Patients were additionally grouped as no trabeculation (grade 0) versus any trabeculation (grades 1–3) and compared using non-parametric tests. Linear regression analysis was used to evaluate predictors of treatment response.

A total of 13–14 patients were available for analysis depending on outcome measures. Trabeculation grade was not significantly associated with improvement in OAB total score (r = −0.08) or OAB-QoL (r = −0.31) (all p > 0.05).

When comparing patients without trabeculation (grade 0) to those with any trabeculation (grades 1–3), a trend toward greater improvement was observed in the absence of trabeculation. Median improvement in OAB total score was 4.5 in grade 0 versus 3.0 in grades 1–3 (p = 0.695). Similarly, OAB-QoL improvement was higher in grade 0 patients (median Δ 15.0 vs 12.5, p = 1.000). Baseline symptom severity was identified as a significant predictor of treatment response, whereas trabeculation was not an independent predictor.

Although trabeculation was not statistically associated with overall symptom improvement, patients without trabeculation consistently showed a trend toward better outcomes. This suggests that the absence of trabeculation may reflect a less structurally remodeled and more treatment-responsive bladder phenotype.

The lack of statistical significance should be interpreted in the context of the limited sample size, and the study may have been underpowered to detect clinically relevant differences. The observed trend warrants further investigation in larger cohorts.

Although trabeculation was not an independent predictor of treatment response, patients without trabeculation (grade 0) showed a tendency toward better outcomes, suggesting that the absence of structural bladder remodeling may be associated with a more treatment-responsive phenotype. Trabeculation may therefore serve as a clinically relevant marker to support individualized treatment strategies.

Oh S, Jung JH, Cho SY, Yoo C, Paick J, Jeong SJ. Establishment of the novel cystoscopic classification system for bladder trabeculation in neurogenic bladder.
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Cameron AP, Chung DE, Dielubanza EJ, et al. The AUA/SUFU guideline on the diagnosis and treatment of idiopathic overactive bladder. J Urol. 2024. doi:10.1097/JU.0000000000003985.