Abstract W MP14: Detection of Early Ischemia Varies Extensively with Topography: Concurrent CT versus DWI ASPECTS
Background: Numerous studies have compared CT with DWI ASPECTS, yet differences in timing between study acquisition may impart error or confound. We analyzed a large cohort of concurrently acquired CT and MRI to discern differences in regional variation in the ability to detect early ischemia.
Methods: CT and DWI were acquired within 1 hour of each other during the first 8 hours after symptom onset and pooled from two large academic stroke centers for these analyses. Two raters independently scored CT ASPECTS and DWI ASPECTS at separate reading sessions. Modified DWI-ASPECTS (including only >20% per region) was also scored. Consensus readings were then utilized to compare regional ASPECTS across the 3 ASPECTS scales using the kappa statistic.
Results: 136 patients underwent both CT and DWI within 1 hour of each other in the setting of acute ischemic stroke. Regional involvement on DWI included caudate in 57%, lentiform in 73%, insula in 69%, internal capsule in 24%, M1 in 34%, M2 in 49%, M3 in 36%, M4 in 21%, M5 in 57% and M6 in 41%. The agreement between CT and DWI varied by region, from caudate kappa 0.616 (0.484-0.748), to lentiform 0.602 (0.457-0.748), insula 0.690 (0.558-0.822), internal capsule 0.374 (0.189-0.559), M1 0.583 (0.435-0.731), M2 0.515 (0.389-0.641), M3 0.421 (0.275-0.568), M4 0.453 (0.262-0.644), M5 0.388 (0.268-0.507) and M6 0.500 (0.366-0.634). Modified DWI-ASPECTS (>20% per region) and CT demonstrated overall better agreement, yet still markedly varied by region. In general, CT and DWI ASPECTS reveal good agreement in subcortical structures, whereas very limited agreement is noted in several cortical ischemic regions. Modified-DWI ASPECTS improves cortical agreement, yet remains poor in the internal capsule.
Conclusions: Detection of early ischemia varies considerably depending on the location or topography depicted with either CT or MRI. Deep subcortical regions are best detected with either modality, whereas cortical regions exhibit marked distinctions. Modified DWI ASPECTS improves agreement with CT ASPECTS in cortical regions.
Author Disclosures: D.S. Liebeskind: Consultant/Advisory Board; Modest; Stryker, Covidien. Research Grant; Significant; NIH-NINDS. S.A. Sheth: None. F. Mehrkhani: None. S. Kamalian: None. F. Scalzo: None. M.S. Johnson: None. M.H. Lev: None. A.J. Yoo: Other Research Support; Modest; Dutch Heart Foundation. Research Grant; Significant; Penumbra Inc..
- © 2015 by American Heart Association, Inc.