Factors that Can Help Select the Timing for Decompressive Hemicraniectomy for Malignant MCA Stroke.

In patients with malignant middle cerebral artery (MMCA) stroke, a vital clinically relevant question is determination of the speed with which infarction evolves to select the time for decompressive hemicraniectomy [DHC]. A retrospective, multicenter cross-sectional study of patients referred for DHC, based on the criteria of randomized controlled trials, was undertaken to identify factors for selecting the timing of DHC in MMCA stroke, stratified by time [< 48, 48-72, > 72 h]. Infarction volume and infarct growth rate [IGR] were measured on all CT scans. One hundred eighty-two patients [135 underwent DHC and 47 survived without DHC] were included in the analysis. After multivariate adjustment, factors showing the strongest independent association with DHC were patients < 55 years of age, septum pellucidum deviation, temporal lobe involvement, MCA with additional infarcts, and IGR on second CT. Of the five factors identified, different combinations of determining factors were observed in each subgroup. Both first and second IGRs were highest in the < 48, 48-< 72, and > 72 h [p < 0.001]. Patients who survived without surgery had the slowest IGRs. There was no association between time to DHC and infarct volume, although infarct volume was lower in patients who survived without DHC compared to the DHC subgroups. We identify the major risk factors associated with DHC in time-stratified subgroups of patients with MMCA. Evaluation of IGRs between the first and second scan and when possible second and third scan can help in selecting the timing of hemicraniectomy.