Clinical criteria for the assessment of a permanent shunting after endovascularly treated aneurysmal subarachnoid hemorrhage (aSAH): Endovascular Risk of Shunt Score (EROS-Score)

OBJECTIVE An exact classification for estimating the risk of shunt dependent hydrocephalus (SDHC) after endovascularly treated aneurysmal subarachnoid hemorrhage (aSAH) is still missing, although studies underline that the type of aneurysm care (clipping/ coiling) has a decisive influence on the development of a SDHC. METHODS A total of 91 patients were selected who underwent an endovascularly treated aSAH at the Department of Neurosurgery of the University Hospital Augsburg from January 2010 to July 2015. Clinical variables, radiographic features and amount of cerebrospinal fluid (CSF) drainage via external ventricular drainage (EVD) were included in the scoring process. We determined the optimal cutoff values by an univariate logistic regression for each dichotomized variable and the Akaike Information Criterion (AIC). Finally, the EROS-Score was established. RESULTS A ventricular Score > 0,6 (p <0.001), poor GCS (< 10; p = 0.001), age over 46 years (p <0.001), cerebral vasospasm (p <0.001) and a CSF drainage volume over 180 ml per day (p = 0.001) in the first week of treatment, were identified to be risk factors of shunt dependency. Out of these independent risk factors the Endovascular Risk of Shunt Score (EROS-Score) was developed. The Area under the receiver operating curve (AUROC score = 0.90) shows a good performance of this score. Patients with > 3 points showed a significantly high risk of shunt dependency. CONCLUSION The EROS score is easy to determine and showed a good predictive value in the investigated patient population. Prospective validation is still needed.