Early prediction of gross hemorrhagic transformation by noncontrast agent MRI cluster analysis after embolic stroke in rat

• Published in: Stroke (1970) 2005-06, Vol.36 (6), p.1247-1252
• Main Authors: GUANGLIANG DING, NAGESH, Vijaya, QUAN JIANG, LI ZHANG, ZHENG GANG ZHANG, LIAN LI, KNIGHT, Robert A, QINGJIANG LI, EWING, James R, CHOPP, Michael
• Format: Article
• Language: English
• Subjects: Animals; Biological and medical sciences; Blood-Brain Barrier; Cluster Analysis; Combined Modality Therapy; Disease Models, Animal; Headache. Facial pains. Syncopes. Epilepsia. Intracranial hypertension. Brain oedema. Cerebral palsy; Hemorrhage - diagnosis; Hemorrhage - pathology; Immunotherapy; Magnetic Resonance Imaging - methods; Male; Medical sciences; Nervous system (semeiology, syndromes); Neurology; Neuropharmacology; Neuroprotective agent; Pharmacology. Drug treatments; Platelet Aggregation Inhibitors - therapeutic use; Platelet Glycoprotein GPIIb-IIIa Complex - immunology; Predictive Value of Tests; Rats; Rats, Wistar; Recombinant Proteins - therapeutic use; Stroke - diagnosis; Stroke - pathology; Time Factors; Tissue Plasminogen Activator - therapeutic use; Vascular diseases and vascular malformations of the nervous system
• ISSN: 0039-2499; 1524-4628
• DOI: 10.1161/01.STR.0000166199.10017.c5

Our goal was to develop magnetic resonance indices, without image contrast agent enhancement, that predict hemorrhagic transformation (HT) in a rat model of embolic stroke. Male Wistar rats subjected to embolic stroke with (n=12) or without (n=10) the combination treatment with recombinant tissue plasminogen activator and an anti-platelet glycoprotein IIb/IIIa antibody 7E3 F(ab')2 initiated at 4 hours after onset of stroke were investigated using a 7-T MRI system. Radiofrequency saturation T1 (T1sat) maps with magnetization transfer, apparent diffusion coefficient of water (ADCw) maps in 3 directions, and T2 maps were measured at 2, 24, and 48 hours after embolization. MRI data were analyzed individually and using 2D cluster plots. Histological measurements were obtained at 48 hours. Gross hemorrhage was detected at 48 hours in 7 (4 control, 3 treated) of 22 animals. The 2D cluster plot using MRI T1sat and ADCw maps obtained at 2 hours after stroke predicted all gross HT. The location of gross hemorrhage predicted by the 2D cluster plot was within 0.75 mm of the identifying MRI cluster. The 2D MRI cluster plot analysis using T1sat and ADCw maps acquired at 2 hours after the onset of embolic stroke predicts gross HT.