Cerebral vasospasm accounts for an increased morbidity and mortality in patients with spontaneous subarachnoid hemorhage (SAH). Its early and non invasive detection by transcranial Doppler (TCD) may contribute to a better prognosis in such cases. PURPOSE: To discuss the use of transcranial Doppler (TCD) in the detection of cerebral vasospasm secondary cerebral to spontaneous subarachnoid hemorrhage (SAH). METHODS: We analyzed the flow velocities registered by TCD in intracranial arteries in 31 patients with SAH, performed sequentially, associated with neurological examinations. All patients (except one) had intracranial aneurysms. RESULTS: Clinical vasospasm was found in 11 patients (36,6% from the total), with correspondent sonographic vasospasm present in 9 cases (82%). In 3 cases (33.3%) the flow velocity alterations preceded the clinical symptoms. Between the 20 asymptomatic patients, 15 (75%) had normal flow velocity, with evidence of sonographic vasospasm without clinical repercussion in 5 (25%). The index of false negatives in the correlation between clinical examination and TCD (symptomatic vasospasm with normal flow velocity records) was 18%. However, there was correspondence between clinical and ultrasonographic findings in 26 of the 31 patients (83.8%). The average flow velocity values in the various arteries and its interpretation for each subgroup are discussed with further details. CONCLUSION: TCD is a valuable auxiliary method in the detection of cerebral vasospasm (even pre-symptomatic) secondary to SAH, allowing a more precocious therapeutic intervention. Our results are similar to those described in the literature.
Transient cerebral ischemia; Ultrasonography; Diagnosis