Proton magnetic resonance spectroscopic findings of cerebral fat embolism induced by triolein emulsion in cats.
BACKGROUND
In experimental studies, embolization of the cerebral hemisphere with triolein emulsion has revealed reversible magnetic resonance imaging (MRI) findings in the subacute stage.


OBJECTIVE
To investigate the changes in the major metabolites, by proton magnetic resonance spectroscopy (MRS), in a cerebral fat embolism induced by a triolein emulsion.


METHODS
The internal carotid arteries of 19 cats were injected with a triolein emulsion, and multivoxel MRS was performed 30 min, 1 day, and 7 days later. In the control group, six cats were injected with normal saline. The MR spectra were evaluated for N-acetyl aspartate (NAA), creatine (Cr), and choline (Cho), along with the presence of lipid and lactate. Semiquantitative analyses of NAA/Cr, Cho/Cr, NAA/Cho, and lipid/Cr ratios compared the median values of the ipsilateral metabolite ratios with those of the contralateral side and in the control group for each point in time.


RESULTS
The NAA/Cr, Cho/Cr, and NAA/Cho ratios in the ipsilateral cerebral hemisphere of the embolized group after 30 min, 1 day, and 7days were not significantly different from the contralateral hemisphere of the embolized and control groups (P>0.05). The lipid/Cr ratio in the ipsilateral cerebral hemisphere of the embolized group was significantly higher when compared with the control group (P=0.012 at 30 min, P=0.001 on day 1, and P=0.018 on day 7).


CONCLUSIONS
Cerebral fat embolism induced by a triolein emulsion resulted in no significant change in the major metabolites of the brain in the acute stage, except for an elevated lipid/Cr ratio, which suggests the absence of any significant hypoxic-ischemic changes in the lesions embolized using a fat emulsion.
Baik
S K
SK
Department of Radiology, College of Medicine and Medical Research Institute, Pusan National University, Pusan, South Korea.
Kim
Y-W
YW
Kim
H J
HJ
Lee
J W
JW
Cho
B M
BM
Kim
D-H
DH
Choi
S H
SH
Lee
S H
SH
Chang
K H
KH
D000818:Animals; D001224:Aspartic Acid / Q000031:analogs & derivatives / Q000032:analysis / Q000378:metabolism; D001921:Brain / Q000378:metabolism; D002415:Cats; D002794:Choline / Q000032:analysis / Q000378:metabolism; D003287:Contrast Media; D003401:Creatine / Q000032:analysis / Q000378:metabolism; D004195:Disease Models, Animal; D018450:Disease Progression; D004620:Embolism, Fat / Q000139:chemically induced / Q000175:diagnosis / Q000378:metabolism*; D005500:Follow-Up Studies; D019786:Gadolinium DTPA; D007089:Image Enhancement / Q000379:methods; D020766:Intracranial Embolism / Q000139:chemically induced / Q000175:diagnosis / Q000378:metabolism*; D019344:Lactic Acid / Q000032:analysis / Q000378:metabolism; D050356:Lipid Metabolism / Q000187:drug effects; D008055:Lipids; D008279:Magnetic Resonance Imaging / Q000379:methods; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D012965:Sodium Chloride / Q000008:administration & dosage; D014304:Triolein / Q000008:administration & dosage*
D003287:Contrast Media; D008055:Lipids; D014304:Triolein; D001224:Aspartic Acid; D019344:Lactic Acid; D012965:Sodium Chloride; C000179:N-acetylaspartate; D019786:Gadolinium DTPA; D003401:Creatine; D002794:Choline