Evaluation of the integrity of the blood-brain barrier after meningeal trauma.
OBJECTIVE
The authors used magnetic resonance imaging (MRI) techniques to examine the effect of meningeal trauma produced by cisterna magna puncture on the integrity of the blood-cerebrospinal fluid barrier (BCB) in a rat model.


METHODS
Intravenous gadolinium-DTPA (Gd-DTPA), a relaxation rate modifier which normally does not cross the BCB, was used as a probe to follow leakage of fluid across the BCB. After Gd-DTPA injection, cerebrospinal fluid (CSF) serial samples were obtained through the needle used to create the experimental trauma. These samples were subsequently examined in vitro by MRI to obtain their T1 relaxation rates and assayed by mass spectrometry for gadolinium and elemental iron concentrations.


RESULTS
The iron levels reflected the severity of puncture-related subarachnoid hemorrhage. Rats with ongoing meningeal damage showed significantly higher CSF levels of gadolinium and significantly higher CSF T1 relaxation rates than controls at all samples times over 1 hour after the puncture. Blood in the CSF could not explain these changes because the CSF iron levels did not significantly differ from control levels.


CONCLUSIONS
Intravenously administered Gd-DTPA can gain access to the subarachnoid space through minor defects in the BCB and cause significant increases in CSF T1 relaxation rates.
Walker
J D
JD
Magnetic Resonance Laboratory, Toronto Western Hospital, Canada.
Martin
M A
MA
Potts
D G
DG
Lemaire
C
C
Templeton
D M
DM
D000818:Animals; D001812:Blood-Brain Barrier; D002946:Cisterna Magna / Q000293:injuries*; D019786:Gadolinium DTPA; D007275:Injections, Intravenous; D008279:Magnetic Resonance Imaging; D008297:Male; D009942:Organometallic Compounds / Q000008:administration & dosage / Q000493:pharmacokinetics*; D004369:Pentetic Acid / Q000008:administration & dosage / Q000493:pharmacokinetics*; D051381:Rats; D011919:Rats, Inbred Strains; D013129:Spinal Puncture / Q000009:adverse effects*
D009942:Organometallic Compounds; D004369:Pentetic Acid; D019786:Gadolinium DTPA