The role of MRI in screening for neurogenic hypertension.

Neurovascular compression (NVC) of the left ventrolateral medulla (VLM) has been implicated as a cause of essential hypertension. We investigated whether high-resolution MRI of the posterior cranial fossa could identify patients with essential hypertension who may benefit from surgery. A retrospective analysis of imaging and clinical records from 162 patients was performed. There were 38 patients with essential hypertension and 124 who were normotensive. Contact or compression of the VLM was present in 42.1 % (16/38) of the hypertensive group on the left and 47.3 % (18/38) on the right. In the normotensive group it was seen in 32.2 % (40/124) on the left and 26.6 % (33/124) on the right. There was no significant difference between the hypertensive and control groups with regard to contact or compression of the left VLM. The results support the contention that neurovascular compression (NVC) of the left or right VLM is a common finding on MRI in normotensive individuals. We therefore believe that high-resolution MRI cannot be used as a screening tool to identify patients who may benefit from surgery.