Changes in phosphorus-31 magnetic resonance spectra caused by epidural balloon in cats.
Changes in brain high energy phosphate metabolite and pH levels were studied using serial phosphorus (P)-31 magnetic resonance spectroscopy (MRS) in an epidural balloon cat model. The balloon was inflated with 1, 2, 3, or 4 ml of water at 1 ml/sec and deflated after obtaining a spectrum 4 minutes later. Serial spectra, intracranial pressure (ICP), physiological parameters, and the pupil sizes were observed for 1 hour. The mean ICP after balloon inflation increased to between 36 +/- 3 and 130 +/- 6 mmHg. Some animals showed oculomotor paralyses. Phosphocreatine, adenosine triphosphate, phosphodiester, and phosphomonoester levels suddenly decreased after inflation and gradually recovered after balloon deflation. Acidosis progressed with cerebral compression for 4 minutes and gradually recovered. All changes and recovery were volume related. This study demonstrates the potential of P-31 MRS for noninvasive, serial, in vivo measurements of critical high energy phosphate metabolites and intracellular pH after head injury.
Kobayashi
H
H
Department of Neurosurgery, Fukui Medical School.
Hayashi
M
M
Kabuto
M
M
Handa
Y
Y
Kawano
H
H
Ide
H
H
D000818:Animals; D001921:Brain / Q000378:metabolism* / Q000473:pathology; D002404:Catheterization; D002415:Cats; D004824:Epidural Space; D005260:Female; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D010710:Phosphates / Q000378:metabolism; D010758:Phosphorus
D010710:Phosphates; D010758:Phosphorus