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


METHODS
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.


RESULTS
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.


CONCLUSIONS
The 2D MRI cluster plot analysis using T1sat and ADCw maps acquired at 2 hours after the onset of embolic stroke predicts gross HT.
Ding
Guangliang
G
Department of Neurology, Henry Ford Health Sciences Center, Detroit, MI 48202, USA.
Nagesh
Vijaya
V
Jiang
Quan
Q
Zhang
Li
L
Zhang
Zheng Gang
ZG
Li
Lian
L
Knight
Robert A
RA
Li
Qingjiang
Q
Ewing
James R
JR
Chopp
Michael
M
D000818:Animals; D001812:Blood-Brain Barrier; D016000:Cluster Analysis; D003131:Combined Modality Therapy; D004195:Disease Models, Animal; D006470:Hemorrhage / Q000175:diagnosis* / Q000473:pathology*; D007167:Immunotherapy; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D010975:Platelet Aggregation Inhibitors / Q000627:therapeutic use; D019039:Platelet Glycoprotein GPIIb-IIIa Complex / Q000276:immunology; D011237:Predictive Value of Tests; D051381:Rats; D017208:Rats, Wistar; D011994:Recombinant Proteins / Q000627:therapeutic use; D020521:Stroke / Q000175:diagnosis* / Q000473:pathology*; D013997:Time Factors; D010959:Tissue Plasminogen Activator / Q000627:therapeutic use
D010975:Platelet Aggregation Inhibitors; D019039:Platelet Glycoprotein GPIIb-IIIa Complex; D011994:Recombinant Proteins; D010959:Tissue Plasminogen Activator