Ultrasonic Angiology Department, Borough Wing, Guy's Hospital, Guy's & St Thomas' NHS Foundation Trust, St Thomas Street, London, UK.
Pediatr Radiol. 2012 Apr;42(4):470-4. doi: 10.1007/s00247-011-2263-4. Epub 2011 Oct 15.
The Stroke Prevention Trial in Sickle Cell Anaemia (STOP) demonstrated the value of selective transfusion based on transcranial Doppler (TCD) US screening. This facilitated widespread surveillance, but due to reported differences with non-imaging TCD, imaging velocity thresholds have been reduced in some centres.
(1) Retrospectively review velocity measurements obtained by non-imaging and imaging TCD, using a standardised protocol. (2) Determine the impact on STOP classification of different velocity thresholds.
TCD data from 23 children (2-19 years of age) were reviewed. The TCD protocol focused on obtaining the velocity corresponding to the highest audible Doppler frequency. STOP velocity thresholds were the recommended for non-imaging TCD and values reduced by 5-15%.
Non-imaging and imaging TCD velocities were correlated closely with little overall bias. Reducing imaging TCD velocity thresholds increased the number of abnormal and conditional classifications. Abnormal TCD imaging classifications ranged from 1.9% to 37% depending on the degree of correction applied to the velocity data.
The current approach for applying STOP thresholds to imaging TCD data may not be required. Centres need to validate their imaging TCD practice to avoid inappropriate selection of patients for transfusion therapy.
镰状细胞贫血症卒中预防试验（STOP）证明了基于经颅多普勒（TCD）超声筛查的选择性输血的价值。这促进了广泛的监测，但由于报告的与非成像 TCD 的差异，一些中心已经降低了成像速度阈值。
（1）使用标准化方案回顾非成像和成像 TCD 的速度测量值。（2）确定不同速度阈值对 STOP 分类的影响。
回顾了 23 名儿童（2-19 岁）的 TCD 数据。TCD 方案侧重于获得与最高可听多普勒频率对应的速度。推荐用于非成像 TCD 的 STOP 速度阈值和降低 5-15%的阈值。
非成像和成像 TCD 速度密切相关，整体偏差较小。降低成像 TCD 速度阈值会增加异常和条件分类的数量。异常 TCD 成像分类范围为 1.9%至 37%，具体取决于对速度数据应用的校正程度。
目前将 STOP 阈值应用于成像 TCD 数据的方法可能不需要。中心需要验证其成像 TCD 实践，以避免对输血治疗的不适当选择。
