Fig. 2

Cerebral CT immediately after DSA did not indicate any obvious abnormal sign (a, b, c); 2 days after the procedure, a repeat cerebral CT revealed diffuse cerebral oedema, loss of grey-white differentiation, effacement of the cerebral sulci and decrease in cerebrospinal fluid space (d, e, f); 9 days after the procedure, the cerebral CT showed more severe diffuse oedema of the brain, loss of grey-white differentiation, effacement of the cerebral sulci and subarachnoid space, disappearance of the cerebral ventricles, enhancement of the subarachnoid space, and darkened brain tissue in Hounsfield units (g, h, i); 15 days after the procedure, the cerebral CT showed persistent diffuse oedema of the brain with effacement of the cerebral ventricles and sulci, darkened brain tissue in Hounsfield units, and enhancement of the subarachnoid space (j, k, l)