Longitudinal trajectories and determinants of urinary outcomes after spinal ependymoma surgery

Urinary dysfunction is an underexplored component of postoperative morbidity in spinal ependymomas. This study aimed to characterize longitudinal urinary and fecal outcomes, bladder-management trajectories, and predictors of early dysfunction and long-term catheter dependency following surgical resection.

A retrospective cohort study of adult patients undergoing resection of spinal ependymomas was performed (2018-2024). Urinary and fecal outcomes were assessed at baseline, discharge, and 12 months. Bladder management was longitudinally assessed at discharge, 3, 6, and 12 months. Univariable logistic regression was used to identify predictors of postoperative urinary dysfunction and catheter dependency.

Fifty-five adult patients undergoing surgical resection for spinal ependymoma were included. Urinary dysfunction increased from 1.8% at baseline to 20.0% at discharge, then decreased to 12.7% at 12 months, mainly due to urinary retention. Fecal dysfunction remained uncommon throughout follow-up. Among patients with postoperative urinary retention (n = 10), bladder-management trajectories demonstrated progressive recovery over time, with six patients showing a lower level of catheter dependency at 12 months, four remaining unchanged, and no patients worsening. Most favorable transitions occurred within the first 6 months after surgery. Notably, no patient requiring an indwelling catheter at discharge remained dependent on it at 12-month follow-up. Subtotal resection (OR 6.34, p = 0.012) and intraoperative neurophysiological alterations (SSEP: OR 17.50, p < 0.001; MEP: OR 16.88, p < 0.001) were associated with postoperative urinary dysfunction. Histological subtype and tumor location were not associated with early postoperative urinary dysfunction but showed a descriptive relationship with longitudinal bladder-management outcomes.

Urinary dysfunction is common after spinal ependymoma surgery but often improves over time. Early indwelling catheter dependency should not be considered a definitive poor prognostic sign, while extent of resection and intraoperative neurophysiological alterations appear to identify patients at increased risk of early postoperative urinary dysfunction.