Non-contrast CT good imaging option before mechanical thrombectomy in extended time window: JAMA

This multinational cohort study included consecutive patients with proximal anterior circulation occlusion stroke presenting within 6 to 24 hours of time last seen well from January 2014 to December 2020. This study was conducted at 15 sites across 5 countries in Europe and North America. The duration of follow-up was 90 days from stroke onset. Computed tomography with Alberta Stroke Program Early CT Score, CTP, or MRI were used.

The primary end point was the distribution of modified Rankin Scale (mRS) scores at 90 days (ordinal shift). Secondary outcomes included the rates of 90-day functional independence (mRS scores of 0-2), symptomatic intracranial hemorrhage, and 90-day mortality.

The Results of the study are as follows:

• Of 2304 patients screened for eligibility, 1604 patients were included, with a median (IQR) age of 70 (59-80) years; 848 (52.9%) were women.
• A total of 534 patients were selected to undergo mechanical thrombectomy by CT, 752 by CTP, and 318 by MRI.
• After adjustment of confounders, there was no difference in 90-day ordinal mRS shift between patients selected by CT vs CTP or CT vs MRI
• The rates of 90-day functional independence were similar between patients selected by CT vs CTP but lower in patients selected by MRI than CT
• Successful reperfusion was more common in the CT and CTP groups compared with the MRI group
• No significant differences in symptomatic intracranial hemorrhage or 90-day mortality were observed.

Thus, the researchers concluded that in patients undergoing proximal anterior circulation mechanical thrombectomy in the extended time window, there were no significant differences in the clinical outcomes of patients selected with noncontrast CT compared with those selected with CTP or MRI. These findings have the potential to widen the indication for treating patients in the extended window using a simpler and more widespread noncontrast CT–only paradigm.

Reference:

Noncontrast Computed Tomography vs Computed Tomography Perfusion or Magnetic Resonance Imaging Selection in Late Presentation of Stroke With Large-Vessel Occlusion by Thanh N. Nguyen et. al published in the JAMA Neurology.