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Multiple system atrophy is a disorder characterized by progressive neuronal atrophy at certain sites of the central nervous system, several of which are important in the control of urogenital function. The neuro-urological features of 62 patients with this condition are described. All patients had abnormal urethral or anal sphincter electromyography when individual motor unit analysis was performed, a finding diagnostic of the condition in the appropriate clinical setting. Impotence occurred in 96% of the men and was the first symptom alone in 37%. Urinary symptoms resulted from a combination of detrusor hyperreflexia and urethral sphincter weakness followed by failure of detrusor contraction. In men these symptoms simulated those of outflow obstruction so that 43% underwent prostatic or bladder neck surgery before the correct diagnosis was made. Stress incontinence occurred in 57% of the women and of these half had undergone surgery. The results of surgery in both sexes were poor. Treatment with intermittent catheterization, anticholinergic medication and desmopressin spray markedly improved continence in 82%. The importance of recognizing this disorder and introducing effective, nonoperative treatments is stressed.

An intravesical instillation of 100 ml 1 or 2 mmolIl capsaicin has been used to treat detrusor hyperreflexia giving rise to intractable urinary incontinence in 12 patients with spinal cord disease and two other patients with detrusor overactivity of non-spinal origin. Nine patients, all of whom had spinal cord disease, showed some improvement in bladder function. The benefit was only shortlived and partial in four, but the remaining five achieved complete continence while performing intermittent self catheterisation. Urodynamic studies in these nine patients showed an increase in mean (SD) bladder capacity from 106 (57) to 302 (212) ml and a fall in the maximum detrusor pressure from 54 (20) Detrusor hyperreflexia can result either from loss of the normal inhibitory input from higher centres on to the pontine micturition centre or after a spinal lesion from interruption of the spinobulbospinal pathways that normally control physiological bladder behaviour. Animal models of chronic spinal cord disease have shown that after disruption of the connections between the pons and the sacral spinal cord a new segmental sacral reflex arc becomes functional.' The afferent neurones of this emergent reflex in the cat are mostly unmyelinated C fibres whereas in the neurologically intact animal afferent neurones from the bladder are small myelinated A5 fibres.2 Little is known of the neurological mechanism of bladder reflexes in spinally injured humans.' Disconnection of the sacral cord from the pons results in detrusor areflexia that lasts for about six weeks before volume determined bladder reflex emptying becomes established. A speculative hypothesis is that this change in detrusor behaviour results from synaptic reorganisation and possibly new nerve growth forming the neurological basis of an emerging reflex arc.Pharmacological experiments show that in many species there is a large group of fibres innervating the bladder that are capsaicin sensitive.3-6 These are mostly unmyelinated fibres in the cat' and rat.7 They are silent under physiological conditions but may be activated by bacterial or chemical irritants in the bladdere giving rise to symptoms of cystitis. It is probably these same fibres that emerge active and serve as the afferent arc for detrusor hyperreflexia in spinally injured animals. ' Capsaicin activates a vanilloid receptor on the cell membrane of sensitive primary sensory neurones9 causing an increase in cation permeability and leading to membrane depolarisation. Activation of the vanilloid receptor produces a biphasic response. The immediate effect is stimulatory with transmission of sensory impulses from the periphery to the central nervous system sensed as a painful irritation and a peripheral release from the receptor terminals of neuropeptides including substance P and CGRP. After exposure to high concentrations of capsaicin, afferent C fibres may show long lasting functional

Forty-eight men with multiple sclerosis and erectile dysfunction were evaluated. Emphasis was placed on the neurological features and the relationship between impotence and the bladder dysfunction in multiple sclerosis. Erectile failure was invariably associated with pyramidal signs in the lower limbs and with urinary symptoms. All of the men with impotence and marked pyramidal dysfunction in their legs were found by cystometric studies to have bladder hyperreflexia. The severity of the urinary symptoms was related to the degree of pyramidal impairment in the lower limbs. The posterior tibial and the pudendal cortical evoked potentials were abnormal in most of the men with multiple sclerosis and erectile failure. However, recording the pudendal cortical responses in patients with multiple sclerosis and impotence provided no more information than the tibial cortical evoked potentials. The neurological examination findings together with the results of the neurophysiological and cystometric tests suggest that erectile dysfunction in multiple sclerosis is due to spinal lesions situated proximal to the sacral cord. The feasability of papaverine intracorporeal injection therapy for men with multiple sclerosis and impotence was assessed. Papaverine intracorporeal injections produced satisfactory erections in the majority of the impotent men. Erectile failure in patients with multiple sclerosis was successfully managed for up to 2 years, by intracorporeal self-injection therapy.

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