Along with rapid increase of aged population in Japan, number of patients with iNPH, who are known well to easily tumble and fall, has been increasing. In this study we investigated frequency of preoperative episode of injury by tumbling accident and resultant brain injury in 144 patients who underwent surgical treatment for iNPH. Approximately 70% of the patients suffered tumbling injury, and 45% of them had multiple episode of tumbling. As more than a half of the patients with tumbling injury had associated traumatic brain injury, although the severity of which was mild, it is strongly suggested that elderly patients with iNPH should be carefully diagnosed and properly treated by shunt surgery to improve their gait disturbance, which must reduce the potential risk that they might suffer from a severe brain injury associated with accidental tumbling.
