RESUMO
OBJECTIVE: Surgery for chronic subdural hematoma is one of the most frequent operations in neurosurgical practice. Chronic subdural hematoma mostly afflicts the elderly population. In 2018, Kwon and co-workers, published the Kwon scoring system (KSS), whereby 6 clinical and radiological factors are used to facilitate, and promote quality in, surgical decision-making and counseling of relatives. The aim of this study is to validate the KSS. METHODS: Patients operated on for unilateral chronic subdural hematoma at Örebro University Hospital, Sweden, between 2013 and 2019 constituted the study population. General data and the 6 outcome predictors according to the KSS were extracted from the electronic patient records. The preoperative modified Rankin Scale score and the postoperative 6-month modified Rankin Scale score were assessed. RESULTS: We identified 133 patients (69.2% male) with a median age of 80.2 years (interquartile range 72.6-85.9). The median Glasgow Coma Scale score at admission was 15; 57.1% had motor deficits and 36.81% were disoriented. For 39.1% of the patients, the prognosis was a favorable outcome (modified Rankin Scale 0-1) at 6 months. The median KSS score was 9; 63.9% of the patients scored ≥9, and 36 (42.4%) of these patients actually achieved a favorable outcome. This corresponds to a prediction model sensitivity of 0.667 and specificity of 0.424. A receiver operator characteristic curve analysis of the model yielded an area under the receiver operator characteristic curve of 0.62441. CONCLUSIONS: In our material, the KSS did not predict outcome precisely enough to base treatment decisions or counseling of relatives on the scores obtained.
