Abstract
We attempted to set criteria for the diagnosis of vertebro-basilar insufficiency (V.B.I.) based upon neurotological findings by reviewing the literature and by analyzing our own clinical experience.
The criteria are as follows : i) Vertigo or dizziness in association with symptomes caused by some disorder of the central nervous system, such as syncope, motor weakness, glove and stocking paresthesia, visual disturbances, altered consciousness, etc. ii) Abnormal eye movements in the gaze nystagmus test, which could indicate some lesion in the central nervous system. Quite often one might see a vertical down beat nystagmus in the head hanging position of Stenger's maneuver. iii) Saccadic or ataxic ocular pursuit in the eye tracking test, iv) Abnormal findings of the optokinetic after nystagums test, which could suggest some disorder in the central nervous system, usually decreased optokinetic after nystagmus v) Abnormal x-ray findings in the cervical spine, e.g. cervical spondylosis.
Diseases which could cause vertigo or dizziness other then V.B.I. should be ruled out.
A partient with abnormalities of all five items has definite V.B.I., one with four or three abnormal items has probable V.B.I., and one with two items has possible V.B.I., To establish these criteria of V.B.I., we analyzed 250 partients with vertigo experienced during the past three years. Peripheral vertigo was pressent in 39% and central vertigo in 23%. V.B.I. was diagnosed in 20% of the 250 patients.
Our recent experience with 77 patients with V.B I. was also analyzed statistically.
