Urodynamic study in the neurogenic bladder dysfunction caused by intervertebral disk hernia.

AIMS: To discuss the clinical significance of urodynamic studies in neurogenic bladder dysfunction caused by intervertebral disk hernia.

METHODS: Thirty patients with neurogenic bladder dysfunction caused by intervertebral disk hernia were divided into three groups according to the category of detrusor muscle activity: neurogenic detrusor overactivity without detrusor sphincter dyssynergia (DSD), neurogenic detrusor overactivity with DSD, or detrusor underactivity. The patients were divided into three groups according to the condition of urinary retention and incontinence: urinary retention, urinary incontinence, or neither urinary retention nor urinary incontinence. Also they were divided into three groups according to the location of the intervertebral disk hernia: cervical hernia, thoracic hernia, or lumbar hernia. All patients underwent computer tomography (CT), magnetic resonance imaging (MRI), and urodynamic study. The results were analyzed statistically.

RESULTS: There was significant correlation between the category of detrusor muscle activity, bladder compliance (BC, P < 0.05), and the pressure at maximum flow (P(det,Qmax), P < 0.01). There were significant differences in post void residual (PVR), cystometric capacity (CC), and maximum flow rate (Qmax) between the three groups of urinary retention, urinary incontinence, and the group of neither retention nor incontinence (P < 0.05). There was statistical correlation between the location of the intervertebral disk hernia and the urodynamic results. There was significant correlation between the BC (the threshold was 15 ml/cmH(2)O), detrusor pressure (Pdet, the threshold was 40 cmH(2)O), DSD, the location of intervertebral disk hernia, and the upper urinary tract lesion (P < 0.01).

CONCLUSIONS: Urodynamic studies are indispensable in the classification, diagnosis, treatment, and prognosis of the neurogenic bladder dysfunction caused by intervertebral disk hernia.