Nonneuropathic Neuropathic Bladder-Is it Really Nonneuropathic?

Hinman syndrome is a rare disease with urodynamic findings and a clinical course resembling neuropathic bladder, without a neuropathic etiology. Diffusion tensor imaging is a special technique of magnetic resonance imaging that has recently been used to evaluate the peripheral nerves but has been demonstrated to be applicable for evaluation of the lumbosacral plexus. We examined the lumbosacral plexus using diffusion tensor imaging, which has not previously been reported in patients with Hinman syndrome. The study included 12 patients who fulfilled criteria for Hinman syndrome, with severe bladder dysfunction on urodynamics, renal scarring on scintigraphy and no pathological findings on magnetic resonance imaging. The 12 subjects serving as controls required pelvic or spinal magnetic resonance imaging for reasons other than spinal abnormalities. Evaluation was performed with a 3.0 Tesla magnetic resonance imaging system and 16-channel body coil. Tractography was done to examine the lumbosacral plexus. Fractional anisotropy and mean diffusivity were computed and compared between groups for the right and left plexuses. Mean fractional anisotropy was 0.24 and 0.35 for the right plexus in patients and controls, respectively, and 0.24 and 0.36 for the left plexus. Mean diffusivity was 1.39 for the right and left plexuses in patients, and 1.28 for the right and left plexuses in controls (p <0.001 for all). Our study focusing on the lumbosacral plexus as a possible origin of neuropathy revealed abnormal findings in patients with Hinman syndrome resembling nerve injury series. This is the first known study to provide data showing that Hinman syndrome may have a neuropathic etiology.