Preventing Stroke in Sickle Cell Disease: 2021. The Role of Transcranial Doppler Ultrasound (TCD) When the Use of Transfusion is Problematic

In 2009, as an invited Commentary to the article: “STOP” ing the Harm: When is State Intervention Justified? [1], I wrote that while TCD is an indicator of risk, not a biopsy diagnosis (such as proof of cancer), at some point in the velocity spectrum the high velocity detected by TCD reaches what many—myself included--believe is an unacceptable risk of stroke [2]. Even at the low end of the intervention window, 200 cm/sec Time Averaged Mean of the Maximum (TAMM), the point where periodic transfusion is recommended based on the STOP Trial [3], the risk is at least 10 times background and it goes up from there. The risk is markedly attenuated (>90%) by transfusion. Stroke by its nature is permanent. While some strokes are minor and survival with recovery is the expected outcome, it is not assured.