BOTULINUM-A TOXIN AS A TREATMENT OF DETRUSOR-SPHINCTER DYSSYNERGIA INPATIENTS WITH SPINAL-CORD INJURY - MRI CONTROLLED TRANSPERINEAL INJECTIONS

Objectives-To correlate clinical and urodynamic findings with MRI in p atients with spinal cord injury and detrusor-sphincter dyssynergia who were consecutively treated with transperineal injections of botulinum -A toxin (BTX-A) under EMG control. Methods-Six patients with spinal c ord injury and upper motor neuron bladder dysfunction associated with detrusor-sphincter dyssynergia were prospectively analysed. One hundre d international units (IU) BTX-A (Botox(R) in 1 mi normal saline witho ut preservative) diluted 1 to 1 with 1 mi gadopentetate were injected transperineally under EMG control. MRI was started immediately after n eedle withdrawal. Results-In all six patients gadopentetate was locate d in the external urethral sphincter on MRI. In no patient did traces of gadopentetate appear in the perineal musculature located in the vic inity of the external urethral sphincter. No patient developed resista nce to BTX-A. All patients showed an (ongoing) improvement of their vo iding function after BTX-A injections. Conclusions-Transperineal injec tions of BTX-A under EMG control are efficient in the release or ameli oration of lower urinary tract obstruction due to detrusor sphincter d yssynergia in patients with spinal cord injury. Despite well described methods, EMG of the external urethral sphincter is difficult and it i s not possible to definitively exclude false recordings of the surroun ding perineal musculature. By the use of MRI it was shown that both th e EMG recordings and transperineal injection method are precise.