Racial Disparities in Magnetic Resonance Imaging and Perfusion-Diffusion Mismatch

Abstract

Listen

Translate article

Background The central concept of mismatch between perfusion and diffusion targets identified by magnetic resonance imaging offers an approximation of the tissue at risk of infarction if reperfusion is not achieved. This measure is becoming increasingly relevant in determining eligibility for and prognosis following thrombolytic and endovascular treatments, particularly at extended time windows. A few studies have shown that Black stroke patients are more likely to suffer small-vessel ischemic strokes and fewer cardioembolic strokes occluding large vessels. We investigated the relationship between race and arterial occlusion targets, including diffusion-perfusion mismatch. Methods The LESION study was a prospectively collected cohort of 1,092 consecutive subjects, NIHSS>3, scanned within 24 hours of symptom onset of time last known well. The study collected demographics, presentation including time from last known well (TLKW), imaging findings, and treatments. Perfusion and diffusion imaging targets and diffusion-perfusion “mismatch” was qualitatively assessed. Occlusion at any arterial location was documented and location used to characterize MCAO targets (MCA-M1 or M2) and endovascular targets (ICA or MCA-M1). Results Black subjects were younger (66.3 vs 75.4 years; p Conclusion Persistent racial and ethnic disparities are observed in the presentation of stroke with perfusion diffusion mismatch. The absence of differences in imaging targets present on MRA, particularly with large vessel occlusions, challenges the assumption that the difference in mismatch is due to differences in lesion locations.