Abstract 21: Infarct Distributions Differ in Pediatric Sickle Cell Patients With or Without Large Vessel Vasculopathy
Introduction: Children with sickle cell disease (SCD) have a high risk of ischemic strokes in diverse spatial distributions, but mechanisms responsible for these different patterns are unclear.
Methods: MRIs and MRAs from 2006-2014 were retrospectively collected on SCD children with an overt stroke history. Hemispheres were categorized based on presence or absence of large vessel vasculopathy (Vsc) on MRA. Manually delineated infarcts on FLAIR were individually co-registered to the corresponding T1 MPRAGE maps, and then co-registered onto a common space. Left and right hemispheres were separated with a mask in the common space. Hemispheres were flipped so all with Vsc were oriented as right hemispheres, and those without Vsc as left. Co-registered infarct maps were warped into the final anatomic space and averaged to create a lesion density map. A cerebral blood flow (CBF) map was created from average pseudocontinuous arterial spin labeled measurements prospectively collected on 7 children with SCD and no Vsc.
Results: Of 22 children with SCD and overt stroke history (median 15.5y, 41% male), 14 had Vsc (median 16 y, 50% male) in 19/44 hemispheres. Both non-Vsc and Vsc hemispheres had infarct hot-spots in a predominantly deep white matter watershed distribution, but Vsc hemisphere infarcts were more numerous, more extensive and encompassed more gray matter (Figure). Hot-spots overlapped with regions of lowest flow within the deep white matter on the CBF map. Vsc hemispheres also had infarcts in classic large artery territories, not seen in non-Vsc hemispheres.
Conclusions: The etiology of ischemia in SCD is likely multifactorial, involving reduced oxygen delivery (anemia), impaired CBF (Vsc), and possible associated thrombosis (Vsc with low/turbulent flow distal to stenosis). Differential patterns of infarction reflect these different layers of compromise.
Author Disclosures: K.P. Guilliams: None. D.K. Ragan: None. M.E. Fields: None. R.C. McKinstry: None. J.S. Shimony: None. J.N. Rhodes: None. M.L. Hulbert: Other; Significant; Spouse is employed by Pfizer. K.D. Vo: None. J. Lee: None. A.L. Ford: None.
- © 2015 by American Heart Association, Inc.