Comparison of transcranial color Doppler imaging (TCDI) and transcranial Doppler (TCD) in children with sickle-cell anemia

Background. Transcranial Doppler (TCD) has been demonstrated to identify th ose at highest risk of stroke among children with sickle-cell disease. Base d on a randomized clinical trial [Stroke Prevention in Sickle-Cell Anemia T rial (STOP)], which ended in 1997, the National Heart Lung and Blood Divisi on of NIH has recommended TCD screening and chronic blood transfusion based on Nicolet TC 2000 dedicated Doppler (TCD). Studies performed using TCD im aging modalities need to be correlated to that used in the clinical trial t o provide information for treatment decisions when screening with TCDI. Objective. To correlate transcranial arterial time-averaged mean velocities obtained from an Acuson Transcranial Doppler Imaging to those obtained usi ng the TCD as the gold standard for treatment decisions based on STOP. Materials and Methods. A total of 29 children with sickle-cell disease, age 3-16 years, were studied at one of two scanning sessions using both techni ques and a scanning protocol based on that used in STOP performed and read independently. The average difference in the measured velocities for each a rterial segment was tested to determine difference from zero. Differences w ere compared before and after modifications to the TCDI technique were made to mimic the STOP protocol more closely. Results. TCDI velocities were generally lower than TCD velocities for the s ame segment, but the difference was reduced (from 15% to 10% for the middle cerebral artery) by modifications to the TCDI protocol. Conclusions. Measurements using the Acuson system are modestly lower than t hose obtained with dedicated Doppler using the Nicolet TCD.