Patients with abnormal velocities. (A) The KM estimate of the cumulative proportion of patients with abnormal TCDI who converted to normal TCDI while receiving transfusions was 43% (95% CI, 32.6-53.4) at 1 year, 66.5% (95% CI, 56.3-76.7) at 2 years, and 86.4% (95% CI, 78.2-94.6) at 4 years. (B) KM estimates of the probability of TCDI normalization on chronic transfusion depending on the presence of stenosis at first MRA after abnormal TCDI detection. Significant differences were observed depending on the presence of stenosis at the first MRA as after 2 years of transfusion: 25.3% (95% CI, 14.5-36.1) of patients without stenosis still had abnormal velocities vs 61.6% (95% CI, 41.4-81.8) of those with stenosis (log-rank, P < .001). A trend to a significant association with the stenosis grading was observed (P = .058); of note, no TCDI normalization was observed in the 4 patients with grading ≥4.