To Örebro University

OBJECTIVE: Surgery for chronic subdural haematoma (CSDH) is one of the most frequent operations in neurosurgical practice. CSDH afflicts the elderly population most. In 2018, Kwon and co-workers published the Kwon Scoring System (KSS), whereby six clinical and radiological factors are used to facilitate, and promote quality in, surgical decision-making and counselling of relatives. The aim of this study is to validate the KSS.

METHOD: Patients operated on for unilateral CSDH at Orebro University Hospital, Sweden, between 2013 and 2019 constituted the study population. General data and the six outcome predictors according to the KSS were extracted from the electronic patient records. The pre-operative mRS score and the post-operative six-month mRS score were assessed.

RESULTS: We identified 133 patients (69.2% male) with a median age of 80.2 years (IQR 72.6-85.9). The median GCS at admission was 15; 57.1% had motor deficits and 36.81% were disoriented. For 39.1% of the patients, the prognosis was a favourable outcome (mRS 0-1) at six months. The median KSS score was 9; 63.9% of the patients scored ≥ 9, and 36 (42.4%) of these patients actually achieved a favourable outcome. This corresponds to a prediction model sensitivity of 0.667 and specificity of 0.424. A ROC curve analysis of the model yielded an AUC of 0.62441.

CONCLUSION: In our material, the KSS did not predict outcome precisely enough to base treatment decisions or counselling of relatives on the scores obtained.