Idiopathic Normal-Pressure Hydrocephalus: Diagnostic Accuracy of Automated Sulcal Morphometry in Patients With Ventriculomegaly.

Background Idiopathic normal-pressure hydrocephalus (iNPH) is a treatable cause of gait and cognitive impairment. iNPH should be differentiated from ventriculomegaly secondary to brain atrophy to choose the best therapeutic option (ventriculoperitoneal shunt vs medical management). Objective To determine the diagnostic accuracy of automated sulcal morphometry to differentiate patients with iNPH from patients with ventriculomegaly of neurodegenerative origin. Methods Thirty-eight consecutive patients with iNPH (shunt responsive n = 31, nonresponsive n = 7), 35 with vascular cognitive disorder, and 25 age- and sex-matched healthy controls were prospectively included and underwent cognitive evaluation and 3T brain magnetic resonance imaging. Sulcal opening of 10 sulci of interest was retrospectively measured using an automated surface-based approach from the 3-dimensional T1-weighted images. Receiver-operating characteristic curve analyses determined the best parameter to identify iNPH patients. Results The best parameter to discriminate shunt-responsive iNPH from patients with vascular cognitive disorder and healthy controls was the ratio between calcarine sulcus and cingulate sulcus opening with an area under the curve of 0.94 (95% CI: 0.89, 0.99). A cut-off value of 0.95 provided the highest sensitivity (96.8%) and specificity (83.3%). Conclusion This preliminary study showed that automated sulcal morphometry may help the neurosurgeon to identify iNPH patients and to exclude other causes of ventriculomegaly.