Huntington's chorea associated with normal pressure hydrocephalus.

Two patients with Huntington's chorea (HC) developed a gait disturbance more suggestive of normal pressure hydrocephalus (NPH) than HC. The diagnosis of NPH was confirmed by pneumoencephalography and isotope cisternography. Both patients were shunted and both showed an improvement not only in their gait but, unexpectedly, a decrease in their abnormal involuntary movements (AIMs). The association of HC with NPH is discussed.