Attenuated corticomedullary contrast: An early cerebral computed tomography sign indicating malignant middle cerebral artery infarction. A case-control study.

Background and Purpose: No neuroradiological markers have been characterized that support a timely decision for decompressive surgery in malignant middle cerebral artery (MCA) infarction (mMCAI). This case-control study was designed to analyze whether early cerebral CT (CCT) scanning provides reliable information for the prospective selection of stroke patients at risk of developing mMCAI.
Methods: Thirty-one pairs (n=62) were formed with cases (mMCAI) and controls (acute but not malignant MCA infarction) closely matched in terms of age, sex, and stroke etiology. CCT was performed within 18 hours of stroke onset and analyzed by a blinded neuroradiologist according to a defined panel of 12 CCT criteria.
Results: In terms of predicting mMCAI, the criteria of extended MCA territory hypodensities >67% and >50%, hemispheric brain swelling, midline shift, and hyperdense MCA sign exhibited high specificity (100%, 93. 5%, 100%, 96.7%, and 83.9%, respectively) but low sensitivity (45.2%, 58.1%, 12.9%, 19.4%, and 70.9%, respectively). Two criteria yielded high sensitivity (subarachnoid space compressed, 100%; cella media compressed, 80.6%) but low specificity (29% and 74.2%, respectively). The criterion of attenuated corticomedullary contrast yielded both high specificity (96.8%) and sensitivity (87.1%). The latter remained as the crucial criterion [Exp(B)=90.8; 95% CI, 5.8 to 1427. 5] in a 2-tailed logistic regression analysis with the strongest correlating parameters (Spearman correlation factor >/=0.6 or </=-0.6).
Conclusions: The analysis of CCT scans within 18 hours of stroke onset revealed an attenuated corticomedullary contrast as the crucial CCT criterion, which, with both sufficient sensitivity and specificity, predicted mMCAI with 95% certainty.