Video-Urodynamic Characteristics and Predictors of Switching from Botulinum Neurotoxin a Injection to Augmentation Enterocystoplasty in Spinal Cord Injury Patients

Botulinum neurotoxin type A (BoNT-A) injection and augmentation enterocystoplasty (AE) are alternative and effective management strategies for neurogenic detrusor overactivity (NDO) refractory to pharmacotherapy. A great majority of patients with spinal cord injury (SCI) may, however, prefer BoNT-A injections to AE, due to the less invasive characteristics. In this study we evaluated the influence of various video-urodynamic study (VUDS) parameters in SCI patients who continuously received repeat BoNT-A detrusor injections or switched to AE to improve their bladder conditions. We compared the changes in the urodynamic parameters before and after each mode of treatment. In this retrospective study, all SCI patients with refractory NDO who had received at least one BoNT-A injection were enrolled. VUDS was performed before and after both BoNT-A injection and AE. All of the urodynamic parameters of the storage and micturition—including the bladder capacity of every sensation, maximal flow rate (Qmax), post-voiding residual volume, detrusor pressure at Qmax, and bladder contractility index—were recorded. A total of 126 patients, including 46 women and 80 men, with a mean age of 41.8 ± 13.1 years, were recruited for this study. All of the patients receiving either BoNT-A injection or AE had a statistically significant increase of bladder capacity at every time-point during filling and a decrease in detrusor pressure at Qmax during voiding. Patients who switched from BoNT-A to AE had greater improvements in their urodynamic parameters when compared with those who continued with BoNT-A injections. Accordingly, SCI patients receiving BoNT-A injections but experiencing few improvements in their urodynamic parameters should consider switching to AE to achieve a better storage function and bladder capacity.

The Current Positioning of Augmentation Enterocystoplasty in the Treatment for Neurogenic Bladder

Augmentation enterocystoplasty (AEC) is a surgical procedure in which the bladder is enlarged using an intestinal segment in patients with lower urinary tract dysfunction who fail to achieve satisfactory results with all conservative treatments. Currently, surgical materials and procedures, concomitant correction of upper urinary tract abnormalities, or bladder neck reconstruction may vary depending on the experience and preferences of the surgeons. AEC has been proven to be successful with respect to surgical goals, such as achieving urinary continence, improving quality of life, and preserving the upper urinary tract over the long term. The advantage of AEC over intravesical injection of botulinum toxin—a more recent and less invasive procedure—is that the prevention of upper urinary tract damage and the improvement of urinary incontinence are more reliably guaranteed, especially considering that these surgical effects are permanent. Compared to less invasive treatments, the quality of life of patients after surgery is also much higher, and AEC may be more cost-effective in the long run. Thus, in patients with neurogenic bladder, AEC is still the gold standard surgical procedure with strong evidence in support of its efficacy. In this article, the indications, surgical methods, possible complications, long-term follow-up, and current positioning of AEC in lower urinary tract dysfunction is discussed.