Index by author

The authors set out to determine the agreement between collateral flow assessment on CTA and DSA and their respective associations with clinical outcome. They used patient data that was randomized in MR CLEAN with middle cerebral artery occlusion and both baseline CTA images and complete DSA runs. Collateral flow on CTA and DSA was graded 0 (absent) to 3 (good).Of 45 patients with evaluable imaging data, collateral flow was graded on CTA as 0, 1, 2, 3 for 3, 10, 20, and 12 patients, respectively, and on DSA for 12, 17, 10, and 6 patients, respectively. The adjusted odds ratio for favorable outcome on mRS was 2.27 and 1.29 for CTA and DSA, respectively. The relationship between the dichotomized collateral score and mRS 0–2 was significant for CTA, but not for DSA. They conclude that the commonly applied collateral flow assessment on CTA and DSA showed large differences and that these techniques are not interchangeable. CTA was significantly associated with mRS at 90 days, whereas DSA was not.

Twenty-four patients with recurrent high-grade gliomas were scanned before and during bevacizumab treatment with standard and delayed-contrast MRI. The mean change in lesion volumes of responders (overall survival, >1 year) and nonresponders (overall survival, <1 year) was evaluated. Treatment-response-assessment maps (TRAMs) were calculated by subtracting conventional T1WI (acquired a few minutes postcontrast) from delayed T1WI (acquired with a delay of >1 hour postcontrast). These maps depict the spatial distribution of contrast accumulation and clearance. At progression, the increase in lesion volumes in delayed-contrast MR imaging was 37.5% higher than the increase in conventional T1WI. The authors conclude that the benefit of standard and delayed-contrast MRI for assessing and predicting the response to bevacizumab was demonstrated and that the increased sensitivity of delayed-contrast MRI reflects its potential contribution to the management of bevacizumab-treated patients with recurrent HGG.