Quantitative MRI predicts status epilepticus-induced hippocampal injury in the lithium-pilocarpine rat model.
Convulsive status epilepticus (SE) is a common medical neurological emergency and is associated with hippocampal injury and the subsequent development of epilepsy. However, pathophysiological mechanisms that underlie injury remain unclear, and a clinically useful prognostic biomarker of at-risk patients remains elusive. We hypothesised that non-invasive quantitative multi-parametric MRI characterisation of the early time course in the lithium-pilocarpine rat model would provide insight into pathophysiological processes, and may help to develop a non-invasive prognostic marker of hippocampal injury. T(1), T(2), apparent diffusion coefficient (ADC), and cerebral blood flow (CBF) were measured before and after SE on days 0, 1, 2, 3, 7, 14 and 21. Hippocampal volume measurements were used to assess final structural outcome. MRI changes were found in the parietal cortex, hippocampus, piriform cortex, and thalamus. Each of the regions displayed time-dependent changes, and returned to baseline levels by Day 7. Hippocampal measurements peaked on Day 2, and further analysis revealed that the magnitude of these peak changes was predictive of the hippocampal volumes on Day 21. This time course is consistent with cell death and an inflammatory process. The maximal changes provide a potential clinically useful prognostic marker of final hippocampal volume.
Choy
Mankin
M
Radiology and Physics Unit, UCL Institute of Child Health, University College London, London, UK.
Cheung
King K
KK
Thomas
David L
DL
Gadian
David G
DG
Lythgoe
Mark F
MF
Scott
Rod C
RC
D000704:Analysis of Variance; D000818:Animals; D001931:Brain Mapping; D002452:Cell Count; D016923:Cell Death / Q000502:physiology; D002560:Cerebrovascular Circulation / Q000502:physiology*; D006624:Hippocampus / Q000473:pathology*; D007091:Image Processing, Computer-Assisted; D008094:Lithium; D008279:Magnetic Resonance Imaging; D008297:Male; D009929:Organ Size; D010296:Parietal Lobe / Q000473:pathology*; D010862:Pilocarpine; D011237:Predictive Value of Tests; D051381:Rats; D017207:Rats, Sprague-Dawley; D013226:Status Epilepticus / Q000139:chemically induced / Q000473:pathology*; D013788:Thalamus / Q000473:pathology*; D013997:Time Factors
D010862:Pilocarpine; D008094:Lithium