Magnetic resonance imaging detection of multiple ischemic injury produced in an adult rat model of minor stroke followed by mild transient cerebral ischemia

• Published in: Magma (New York, N.Y.) Vol. 30; no. 2; pp. 175 - 188
• Main Authors: Tuor, Ursula I., Qiao, Min
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.04.2017
• Subjects: Animals; Arteries; Biomedical Engineering and Bioengineering; Brain - diagnostic imaging; Brain - pathology; Brain damage; Brain Ischemia - diagnostic imaging; Cell Death; Computer Appl. in Life Sciences; Disease Models, Animal; Health Informatics; Histology; Imaging; Infarction, Middle Cerebral Artery - diagnostic imaging; Ischemia; Ischemic Attack, Transient - diagnostic imaging; Magnetic resonance; Magnetic Resonance Imaging; Male; Medicine; Medicine & Public Health; Radiology; Rats; Rats, Wistar; Recovery; Research Article; Solid State Physics; Stroke - diagnostic imaging; Stroke - physiopathology; Strokes; Temperature; Thrombosis; Ischemic attack; Stroke; Animals; Transient; Magnetic resonance imaging; Cell death
• ISSN: 0968-5243; 1352-8661
• DOI: 10.1007/s10334-016-0597-5

Objectives To determine whether cumulative brain damage produced adjacent to a minor stroke that is followed by a mild transient ischemia is detectable with MRI and histology, and whether acute or chronic recovery between insults influences this damage. Materials and methods A minor photothrombotic (PT) stroke was followed acutely (1–2 days) or chronically (7 days) by a mild transient middle cerebral artery occlusion (tMCAO). MRI was performed after each insult, followed by final histology. Results The initial PT produced small hyperintense T 2 and DW infarct lesions and peri-lesion regions of scattered necrosis and modestly increased T 2 . Following tMCAO, in a slice and a region adjacent to the PT, a region of T 2 augmentation was observed when recovery between insults was acute but not chronic. Within the PT slice, a modest region of exacerbated T 2 change proximate to the PT was also observed in the chronic group. Corresponding histological changes within regions of augmented T 2 included increased vacuolation and cell death. Conclusion Within regions adjacent to an experimental minor stroke, a recurrence of a mild transient cerebral ischemia augmented T 2 above increases produced by tMCAO alone, reflecting increased damage in this region. Exacerbation appeared broader with acute versus chronic recovery between insults.