The etiology of detrusor hyperreflexia in patients with infravesical obstruction.

Bladder function was studied in 44 patients with bladder outlet obstruction by gas cystometry, integrated sphincter electromyography and uroflowmetry. Of these 44 patients 18 demonstrated detrusor hyperreflexia on cystometry. To identify the prostate as a possible source for triggering sensory stimuli pharmacologic ablation with lidocaine was performed through a perineal approach in 11 patients with hyperreflexia. Prostatic block eliminated hyperreflexia in 10 of 11 patients and had no effect in 4 patients with a normal cystometrogram. We believe that this study lends support to the concept that sensory stimuli from an anatomically altered prostatic urethra induces detrusor hyperreflexia. This suggests that permanent ablation of sensory stimuli from the prostate in patients with outlet obstruction would be of benefit.