Deep Learning of Time–Signal Intensity Curves from Dynamic Susceptibility Contrast Imaging Enables Tissue Labeling and Prediction of Survival in Glioblastoma

Calculation of perfusion patterns (A) and representative perfusion patterns (B–D). A, The graph shows signal intensity–time curve elements that can reflect the characteristics of each tissue, such as the baseline signal, minimum signal intensity, and postcontrast signal intensity. On the right side is a summary of the formulas used to calculate each element. Representative perfusion patterns of the reference tissues (B), CEL (C), and NEL (D). B, CSF shows the highest baseline (black line), vascular tissue shows the highest signal drop and drop speed (red line), and normal brain tissue shows the lowest baseline (dotted lines). C, In CELs, perfusion patterns with high signal drop and drop speed are labeled as high angiogenic tumor (red lines), perfusion patterns with the highest baseline and lowest percent recovery are labeled perinecrotic lesion (blue line), and perfusion patterns with the lowest baseline and lowest signal drop are labeled low angiogenic/cellular tumor (black dotted line). D, In NEL, a perfusion pattern with intermediate-to-high baseline and intermediate-to-low signal drop and drop speed is labeled infiltrated edema (green line). A perfusion pattern with the highest baseline and lowest percentage recovery is labeled vasogenic edema (blue line).

Prognostic implication of perfusion patterns of NEL in patients with glioblastoma. A, A 62-year-old man with IDH wild-type glioblastoma (EGFR-negative) exhibited high proportions of infiltrated edema in an NEL in the cerebellum. After maximal safe resection of the contrast-enhancing lesion and concurrent chemoradiotherapy, the patient showed progression at 120 days and died 182 days after diagnosis. Note that the recurrence occurred in both the NEL and the original CEL. B, A 59-year-old man with IDH wild-type glioblastoma (EGFR-negative) had high proportions of infiltrative edema within the NEL. After maximal safe resection, the infiltrative edema was mostly resected. After concurrent chemoradiotherapy, the patient showed progression at 1200 days and died 1237 days after diagnosis. Note that the recurrence occurred distant from the primary site.