Relationship of bladder dysfunction to lesion site in multiple sclerosis

We investigated the relationship of voiding dysfunction type and the lesion site in patients with multiple sclerosis.

Voiding dysfunction was evaluated in 32 patients with multiple sclerosis using the International Prostate Symptom Score and urodynamic tests. Lesion sites were determined by combined neurological examination and magnetic resonance imaging findings.

Compared with reports from Western countries the ratio of emptying-to-filling symptoms was high in Japan. Of urinary symptoms only filling correlated with disability status and disease duration. Urinary symptoms were not related to lesion sites. Urodynamic evaluation revealed detrusor hyperreflexia in 14 of 32 patients, hyporeflexia or areflexia in 12, detrusor hyperreflexia with impaired contractile function in 4, a low compliance bladder in 1 and normal function in 1. Of 14 patients with hyperreflexia 13 had overactive sphincter concurrently. Incompetent sphincter was identified in 2 patients who had detrusor hyperreflexia with impaired contractility and in 1 with a low compliance bladder. A significant correlation was noted for a pontine lesion and detrusor hyporeflexia, and for a cervical cord lesion and detrusor-sphincter dyssynergia.

Detrusor hyporeflexia and detrusor-sphincter dyssynergia are indicative of a pontine and cervical spinal cord lesion, respectively. Thus, the lesion site in the central nervous system may be a major determinant of the type of bladder and urethral sphincter dysfunction. The high prevalence of emptying symptoms in Japanese patients may reflect the prevalence of detrusor hyporeflexia and detrusor-sphincter dyssynergia.