A pilot prospective study to evaluate whether the bladder morphology in cystography and/or urodynamic may help predict the response to botulinum toxin a injection in neurogenic bladder refractory to anticholinergics

Abstract

BackgroundWe have observed different clinical responses to botulinum toxin A (BTX-A) in patients who had similar urodynamic parameters before the procedure. Furthermore, some bladders evaluated by cystography and cystoscopy during the procedure had different characteristics that could influence the outcome of the treatment. The aim of this study was to assess whether cystography and urodynamic parameters could help predict which patients with neurogenic detrusor overactivity (NDO) refractory to anticholinergics respond better to treatment with injection of BTX-A.MethodsIn total, 34 patients with spinal cord injury were prospectively evaluated. All patients emptied their bladder by clean intermittent catheterization (CIC) and had incontinence and NDO, despite using 40 mg or more of intravesical oxybutynin and undergoing detrusor injection of BTX-A (300 IU). Pretreatment evaluation included urodynamic, and cystography. Follow-up consisted of urodynamic and ambulatory visits four months after treatment. The cystography parameters used were bladder shape, capacity and presence of diverticula. Urodynamic parameters used for assessment were maximum cystometric capacity (MCC), maximum detrusor pressure (MDP), compliance and reflex volume (RV).ResultsAfter injection of BTX-A, 70% of the patients had success, with 4 months or more of continence. Before the treatment, there were significant differences in most urodynamic parameters between those who responded successfully compared to those who did not. Patients who responded successfully had greater MCC (p = 0.019), higher RV (p = 0.041), and greater compliance (p = 0.043). There was no significant difference in the MDP (0.691). The cystography parameters were not significantly different between these groups bladder shape (p = 0.271), capacity (p > 0.720) and presence of diverticula (p > 0.999). Statistical analyses were performed using SPSS (version 20.0) and included Student’s t-test for two paired samples and Fisher’s exact test, with a significance threshold of 0.05.ConclusionsThis study suggests that the cystography parameters evaluated cannot be used to help predict the response to injection of BTX-A in the treatment of refractory NDO. However, the urodynamic parameters were significantly different in patients who responded to the treatment, with the exception of the MDP.

Evaluation of bladder shape using transabdominal ultrasound: Feasibility of a novel approach for the detection of involuntary detrusor contractions

“…Clinicians undertaking X-ray video cystography using contrast medium during urodynamics are already aware that the bladder can vary in shape and outline. 10,15 The bladder can appear relaxed, following the normal contours of the pelvis (Figure 1) or more rounded, pear-shaped or fir-tree shaped. 11 Mathematical modelling has previously been used to try and make sense of bladder shape as it fills and empties; however, the clinical application of these methods to-date has been limited.…”

“…[7][8][9] Variations in bladder shape have been observed in association with detrusor overactivity during videourodynamics, when fluoroscopic images are captured during filling with contrast medium. 10,11 At one extreme, women with neuropathic OAB have been observed to have tense, spherical or dome-shaped bladders with trabeculations -'fir tree' or 'Christmas tree' bladder. 11 In women with normal detrusor muscle function, the bladder outline appears relaxed and acontractile, following the contours of the pelvis when assessed by cystography.…”

“…11 In women with normal detrusor muscle function, the bladder outline appears relaxed and acontractile, following the contours of the pelvis when assessed by cystography. 10 We hypothesised that bladder shape changes measured by serial TA-USS may offer a non-invasive method of identifying involuntary, abnormal bladder contractions during filling. The aims of this feasibility study were to evaluate a potential bladder shape test (BlaST) using TA-USS for the detection of involuntary bladder contractions.…”

“…11 In women with normal detrusor muscle function, the bladder outline appears relaxed and acontractile, following the contours of the pelvis when assessed by cystography. 10…”

How to assess and predict success or failure of intra-detrusor injections with onabotulinumtoxinA

“…A prospective study by Álvares et al on individuals who had suffered spinal cord injury (n = 34) showed that patients with greater maximum cystometric capacity responded significantly better than others (LE 2, GR B/C). 38 The authors also demonstrated that cystography parameters, including bladder shape, capacity and the presence of diverticula, were not significantly different between responders and non-responders to the therapy.…”