Kaplan-Meier plots of survival categorized by (A) response (B) tumor volume, (C) relative blood flow (rBF), (D) relative blood volume (rBV), and (E) permeability-surface area product (PS).

<p>For each imaging parameter, two response groups were identified based on whether the measured value was ≤ lower 50% confidence interval of variations across all treated animals derived from the between-subject variation on day 7 post-SRS. Those that met this criteria were ranked as “low” by applying this threshold, and the others were ranked as “high”. Animals with low rBF, rBV, and PS on day 7 post-SRS showed significantly longer survival than the rest of the treated animals (i.e. high rBF, rBV, and PS) and control animals. *Significantly different from control group. †Significantly different from the other treated animals with a “high” value. Significant at <i>P</i>≤0.02 level (log-rank test).</p

Histological examples of stereotactic radiosurgery (SRS) effects.

<p>Representative Hematoxylin & Eosin images of (A) an untreated control, (B) acute histological change at 4 days post-SRS, and (C) late histological change at 59 days post-SRS. Hypercellularity (four point star) and pseudopalisading necrosis (five point star) are classic signs of grade IV glioma, and these were observed in the control animals. Hyalinized blood vessels (arrow) and hypocellularity can be observed shortly after SRS. Regression of tumor and hyalinization of tissue were observed at a later stage after SRS.</p

α-smooth muscle actin (α-SMA) positive vessels in the normal brain, peritumoral region, and tumor of a control and a treated animal after stereotactic radiosurgery (SRS).

<p>Intact α-SMA positive vessels were observed in control animals, but fragmented coverage of vessels by α-SMA is mostly seen in treated animals (red arrow).</p

Boxplots of intact and fragmented α-smooth muscle actin (α-SMA) positive vessel densities in (A) peritumoral region and (B) tumor region for the control and SRS groups.

<p>Pairs with <i>P</i><0.01 are connected by black lines.</p

Summary of histological finding on Hematoxylin and Eosin (H&E) specimens.

<p><i>Abbreviations</i>: PPN, pseudopalisading necrosis; FN, fibrinoid necrosis; BN, background necrosis; EH, endothelial hyperplasia; HBV, hyalinized blood vessels.</p><p>Summary of histological finding on Hematoxylin and Eosin (H&E) specimens.</p