Transcranial color doppler study for reversible cerebral vasoconstriction syndromes.

Abstract

Reversible cerebral vasoconstriction syndromes (RCVS) are characterized by thunderclap headaches and reversible cerebral vasoconstrictions. No systematic studies on cerebral hemodynamics have been published. Patients with RCVS were consecutively recruited. Sequential transcranial color-coded sonography studies were performed on the middle cerebral artery (MCA) for 3 months. Mean flow velocities (V(MCA)) and Lindegaard Index (LI) were recorded and compared with those of controls. Thirty-two patients (all female; average age, 49.7 +/- 6.8 years) were enrolled. Four developed of reversible posterior leukoencephalopathy syndrome, and two of them, ischemic strokes. One hundred and twenty-six sonography studies were performed on 57 eligible MCAs. The mean maximum V(MCA) (109.5 +/- 30.8 cm/sec) and LI (2.2 +/- 0.7) of RCVS patients exceeded those of controls (V(MCA): 66.3 +/- 9.5 cm/sec, p < 0.001; LI: 1.4 +/- 0.3, p < 0.001). The V(MCA) and LI levels were still at their plateau at the mean time (day 22 after headache onset) of headache resolution. Fifteen (46.9%) patients had V(MCA) exceeding 120 cm/sec, and 5 (16%) had LI exceeding 3. Patients fulfilling the criteria of subarachnoid hemorrhage mild vasospasm (n = 4; 13%), that is, both V(MCA) greater than 120 cm/sec and LI greater than 3, had a greater risk of posterior leukoencephalopathy (75 vs 4%; p = 0.003) and ischemic strokes (50 vs 0%; p = 0.01) than those without. Patients with RCVS experienced prolonged vasoconstriction, making the risk for posterior leukoencephalopathy and ischemic strokes outlast headache resolution. Patients fulfilling mild vasospasm criteria for subarachnoid hemorrhage carry a high risk.