Changes in Callosal Angle and Evans Index After Shunt Surgery in Patients with Idiopathic Normal Pressure Hydrocephalus

Idiopathic normal pressure hydrocephalus (iNPH) is a disease characterized by gait disturbance, cognitive impairment, and urinary incontinence. For those patients who do not respond to shunt surgery, it lacks objective radiologic findings for the diagnosis of shunt malfunction. Here we aimed to evaluate whether the Evans index and callosal angle change during a prospective long-term follow-up of patients with iNPH submitted to shunt surgery. Clinical (NPH Japanese Scale) and radiologic (Evans index and callosal angle) data were collected pre- and postoperatively (3, 6, 12 and months) in 19 patients with iNPH. Imaging tests were evaluated by the same neuroradiologist during the follow-up. Patients had lower scores on the NPH Japanese Scale over time (P