Patient characteristics: median values and univariate analyses (t, U, χ², and Fisher's exact tests).

Values are the mean ± SD when appropriate. Significant values are featured with bold font. Three PT-INR values from the NS group (1 recurrent patient) and 2 PT-INR values from the ACF group were missing and were excluded from analysis. Abbreviations: ACF: Artificial cerebrospinal fluid, NS: Normal saline, GCS: Glasgow Coma Score, mRS: Modified Rankin scale, CT: Computed tomography, Hyper: Hyperdense, Iso: Isodense, Hypo: Hypodense, Layer: Layered, Grad: Gradation, Sep: Separated, Trab: Trabecular, PT-INR: International normalized ratio of prothrombin time, POD: Postoperative day.