Transcranial Doppler ultrasonography in neurologically asymptomatic children and young adults with sickle cell disease.

The purpose of the study was to evaluate transcranial Doppler ultrasonography for identifying cerebrovascular disease in neurologically asymptomatic children and young adults with sickle cell disease. A total of 47 consecutive patients with sickle cell disease (28 females, 19 males; age range 8 months to 29 years, mean age 9 years 6 months) were evaluated by transcranial color and duplex Doppler ultrasonography via transtemporal and occipital (2-MHz probe) as well as by transocular (5-MHz probe) approach. Eleven vessels (middle, posterior, anterior cerebral artery, vertebral artery, ophthalmic artery on each side and basilar artery) were analyzed in each patient. Following nine transcranial Doppler findings predictive for cerebrovascular disease, patients with one or more of those abnormal sonographic findings underwent MR imaging and MR angiography. In 8 patients with abnormal transcranial Doppler the MR angiography was normal. Thirty-one patients demonstrated normal results. In 15 of 16 patients with one or more abnormal Doppler findings (34% of all studied patients) MR imaging and MR angiography were performed. The MR angiography disclosed cerebrovascular stenosis in 7 patients (15% of all patients, 44% of those with pathological transcranial Doppler findings). In one of those patients MR imaging revealed silent peripheral ischemic infarction as well. Our findings indicate the usefulness of transcranial Doppler ultrasonography to reveal occult cerebrovascular lesions in neurologically asymptomatic patients with sickle cell disease. It should regularly be performed in all sickle cell patients in order to detect patients at risk for later stroke. Patients with homozygous disease and a high frequency of preceding sickle cell crises should be followed most closely.