EXTRACRANIAL AND INTRACRANIAL VERTEBROBASILAR DISSECTIONS - DIAGNOSISAND PROGNOSIS

Objectives-To compare the diagnosis and prognosis of extracranial vers us intracranial vertebral artery dissections without intracerebral hae morrhage. Methods-Twenty two vertebral artery dissections were defined by intra-arterial angiography and classified in two groups: group 1, nine extracranial dissections (seven patients) and group 2, 13 intracr anial dissections (nine patients), involving the basilar artery in fiv e cases. Bilateral dissections were found in 38% of the population. Be fore angiography, all the patients had been investigated by continuous wave Doppler, colour coded Doppler, and transcranial Doppler. Mean fo llow up was 44 months. Results-The two most important symptoms of both dissections (81% of patients) were unbearable pain preceding stroke a nd progressive onset of stroke within a few hours. Severe ultrasonic a bnormalities were present in 94% of the patients whereas specific ultr asonic signs (segmental dilation with eccentric channel) were rare (19 %) in both groups. Major strokes and brainstem strokes represented res pectively 67% and 78% in intracranial versus 43% and 29% in extracrani al dissections. Severe sequelae (permanent disabling motor or cerebell ar deficit) were more often associated with intracranial (44%) than wi th extracranial dissections (14%). No recurrence of dissection and no cerebral haemorrhage were found under heparin. Significant factors of poor outcome (P<0.05) were the initial severity of the stroke and the bilateral location of dissections. Conclusion-The combination of a pai n and a progressive onset of the stroke, corroborated by ultrasonic fi ndings, could have helped to recognise most of these types of dissecti ons. Intracranial dissections have a poorer prognosis than extracrania l dissections.