Spontaneous Dissection of Both Vertebral Arteries Diagnosed with Three-Dimensional T1-Weighted Image.

A 48-year-old woman spontaneously developed occipital pain, without any other neurological deficit. A brain magnetic resonance angiography showed narrowing, irregular dilatation, and aneurysmal formation in both the vertebral arteries (VA). According to these findings and the clinical course, we diagnosed the patient with spontaneous VA dissection. There was no finding suggesting cerebral infarction or subarachnoid hemorrhage. Three-dimensional T1-weighted magnetic resonance imaging performed 27 days after first onset of headache revealed a crescent-shaped high-intensity lesion in both the VA walls. These findings indicated that the lesions in both VAs were equally in the subacute phase. Follow-up three-dimensional T1-weighted imaging indicated that the high-intensity signals in both VAs disappeared at almost the same time. This case report presents imaging evidence showing that spontaneous dissection occurred simultaneously in both the VAs.