Interobserver reliability of the DESH score in idiopathic chronic hydrocephalus.

Introduction: idiopathic chronic hydrocephalus (iCH) is underdiagnosed in older adults. The diagnosis of iCH is important because effective surgical treatment is available. Indeed, iCH is the only curable dementia. The disproportionately enlarged subarachnoid space hydrocephalus (DESH) score was recently developed on the basis of morphologic MRI data, as a guide to the diagnosis of iCH in adults.

Patients and method: In a population of 68 patients having undergone placement of a ventriculoperitoneal shunt, the preoperative DESH score was calculated retrospectively by a senior neurosurgeon and a neurosurgery resident. To analyze inter-observer variability, the results obtained for each patient were compared. We calculated sensitivity, specificity, positive and negative predictive values of the DESH score.

Results: DESH score of 7 or more present the best diagnostic performance (sensitivity: 83%, specificity: 40%, positive predictive value: 89%, negative predictive value: 29%). The interobserver reliability of the DESH score was excellent, with an intraclass correlation coefficient of 0.936. Similarly, the levels of interobserver agreement for each individual item were fair (for Sylvian fissure dilatation, local focal sulci dilatation, and tight high convexity) to excellent (for the callosal angle).

Conclusion: The DESH score is a reliable score obtained by studying brain MRI and radiographic datasets. The score's excellent reliability means that it can be included in the routine diagnosis of iCH.