Radiological DESH score cannot predict outcome after shunt surgery: A Swedish prospective follow-up study

Background Disproportionately enlarged subarachnoid-space hydrocephalus (DESH) has been proposed as a radiological predictor of shunt responsiveness in idiopathic normal pressure hydrocephalus (iNPH), but previous studies have reported inconsistent results. We investigated the association between preoperative DESH score and postoperative outcome after shunt surgery in a prospective iNPH cohort. Methods This prospective study included 101 consecutive patients with iNPH from the Gothenburg Prediction of Outcome in iNPH (POiNT) study. Preoperative DESH scores were assessed on MRI using previously published criteria. Clinical outcomes included the Gothenburg iNPH scale, modified Rankin Scale (mRS), Mini-Mental State Examination (MMSE), and Timed Up and Go test (TUG-t). The primary outcome was improvement of ≥5 points on the iNPH scale. Results Mean preoperative DESH score was 6.3 ± 1.7. At follow-up, the mean iNPH scale score improved from 50.8 ± 19.8 to 63.3 ± 20.0 ( p < .001), with 70% improving by ≥5 points. Preoperative DESH score was not associated with postoperative change in iNPH scale score ( r = −0.123, p = .219) or with responder status for any outcome. In multivariable analysis, DESH score was not independently associated with postoperative iNPH scale score after adjustment for baseline iNPH scale score, age, and disease duration. DESH score and Evans’ index decreased and callosal angle increased after surgery (all p < .001). Conclusions Preoperative DESH score was not associated with postoperative clinical improvement after shunt surgery in patients with iNPH. Although DESH-related imaging markers changed significantly after surgery, baseline DESH score had limited value as an independent predictor of shunt responsiveness.