When would you consider stopping chronic transfusion therapy in a sickle cell patient with history of abnormal TCDs but no stroke?  

Fortunately, we have good data to answer this question. The TWiTCH trial aimed to determine the efficacy of hydroxyurea at maintaining TCD velocities after discontinuation of initial transfusion therapy to prevent primary stroke. Patients on this non-inferiority trial with a history of abnormal TCD ...