Related Experiment Video
Updated: Apr 18, 2026

An Ex Vivo Laser-induced Spinal Cord Injury Model to Assess Mechanisms of Axonal Degeneration in Real-time
Published on: November 25, 2014
Perilesional edema in radiation necrosis reflects axonal degeneration
Carlos J Perez-Torres1, Liya Yuan2, Robert E Schmidt3
1Department of Radiology, Washington University, Campus Box 8227, 4525 Scott Avenue, Saint Louis, MO, 63110, USA. pereztorresc@wustl.edu.
Background:
Recently, we characterized a Gamma Knife® radiation necrosis mouse model with various magnetic resonance imaging (MRI) protocols to identify biomarkers useful in differentiation from tumors. Though the irradiation was focal to one hemisphere, a contralateral injury was observed that appeared to be localized in the white matter only. Interestingly, this injury was identifiable in T2-weighted images, apparent diffusion coefficient (ADC), and magnetization transfer ratio (MTR) maps, but not on post-contrast T1-weighted images. This observation of edema independent of vascular changes is akin to the perilesional edema seen in clinical radiation necrosis.
Findings:
The pathology underlying the observed white-matter MRI changes was explored by performing immunohistochemistry for healthy axons and myelin. The presence of both healthy axons and myelin was reduced in the contralateral white-matter lesion.
Conclusions:
Based on our immunohistochemical findings, the contralateral white-matter injury is most likely due to axonal degeneration.
Related Concept Videos
Cytotoxic Edema: Pathophysiology
Cerebral Edema ll: Pathophysiology
Secondary Spinal Cord Injury llI: Pathophysiology
Cerebral Edema l: Introduction
Degenerative Disc Disease ll: Pathophysiology
Cellular Injury IV: Necrosis

