Normative Time Averaged Mean Maximal Velocities Value Using Imaging Transcranial Doppler Ultrasound in Stable Sickle Cell Disease Patients in Zaria

Introduction: Middle cerebral artery (MCA) velocimetry in sickle cell patients using noninvasive transcranial ultrasound scan is an important index for predicting stroke. Stroke is one of the most feared clinical complications of sickle cell anemia. Transcranial Doppler (TCD) enables early detection of arterial abnormalities to institute primary preventive measures. Aims and Objectives: The aims and objectives of the study were to determine the normal range of time‑averaged mean maximal velocities (TAMMAX) in the MCA on imaging TCD ultrasound in stable sickle cell patients in Ahmadu Bello University Teaching Hospital (ABUTH), Zaria. Materials and Methods: This was a cross‑sectional study conducted from December 2016 to May 2017 in the Radiology Department of ABUTH, Zaria. Stable sickle cell anemic children numbering 75 within the age of 2–16 years were recruited for the study. Approval was granted by the ethical committee of ABUTH. The TAMMAX of the MCA was measured by Doppler ultrasound which is done with the patient lying supine, the probe is placed on the temporal bone after application of the gel and the MCA assessed on grayscale, color, and spectral Doppler. The results were recorded in the datasheet. Data Analysis: All measurements were analyzed using the Statistical Package for the Social Sciences version 20. P < 0.05 was considered as statistically significant and a confidence interval of 95% was used. TAMMAX was classified based on the STOP criteria. Findings were presented in the form of summarizing indices (tables and charts). Means and standard deviations were computed. Results: A total of 75 patients were included in the final data with a mean age of 8.5 years and male‑to‑female ratio was 1.04:1. The mean TAMMAX of sickle cell subjects was 84.32 cm/s and 80.31 cm/s in the right and left MCA, respectively. Conclusion: The TAMMAX of stable sickle cell disease patients all fell below 170 cm/s and so the detection of abnormal velocities during the scan is an indicator of the likelihood of stroke and so preventive measures can be instituted early