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Vertebral artery compression of the medulla.

BACKGROUND
Intracranial arteries in the subarachnoid space may compress the brain parenchyma and cranial nerves. Most arterial compressive lesions have been attributed to dolichoectasia in the vertebral-basilar system, and prior reports have concentrated on the pressure effects of basilar artery ectasia. Much less is known about vertebral artery compression of the medulla.


OBJECTIVE
To describe a series of patients with vertebral arteries compressing the medulla oblongata.


DESIGN
Prospective case studies.


SETTING
Tertiary care center.


PATIENTS
Nine symptomatic patients, 4 men and 5 women, between the ages of 32 and 79 years.


MAIN OUTCOME MEASURES
Clinical phenomena, radiographic findings, treatment, and outcomes.


RESULTS
We found that compression most commonly occurs at the ventrolateral surface. The clinical features can be transient or permanent and are predominantly motor and cerebellar or vestibular, but a poor correlation exists between the clinical findings and the severity or extent of impingement. The vertebral arteries were angulated, tortuous, or dilated but not necessarily dolichoectatic to cause obvious indentation. Seven patients were treated with antiplatelets and anticoagulants or analgesics, whereas 2 underwent microvascular decompression, resulting in temporary or no relief. One surgical patient developed cranial nerve complications. Among the medically treated patients, none had progression of deficits, and those with single episodes had no recurrence of symptoms.


CONCLUSION
This study is the largest collection, to our knowledge, of patients with medullary vascular compression. Further studies are needed to estimate its frequency, natural course, and preferred management.