Magnetic Resonance Imaging Relaxation Times and Gadolinium-DTPA Relaxivity Values in Human Cerebrospinal Fluid

Abstract

This study was conducted to prove the feasibility of using cerebrospinal fluid (CSF) T1 and T2 measurements to assess the blood-brain barrier integrity in disease states not noted for focal blood-brain barrier disruption, such as Alzheimer's disease. T1 and T2 of human CSF samples were measured with and without gadolinium Gd-DTPA over a concentration range of 1.98 X 10-3 to 6.32 mM, in a GE 1.5-T Signa scanner. T1 and T2 of human CSF without Gd-DTPA were measured as 2.39 and 0.23 s. K1 and K2 were calculated as 6.25 and 6.74 mM-1s-1. The lowest Gd-DTPA concentration with measurable T1 and T2 was 1.98 X 10-3 mM. There is no statistically significant difference in T2 and K2 at different repetition times. This work demonstrates that a single measurement of relaxation times after contrast-enhanced magnetic resonance imaging could be used to determine the Gd-DTPA concentration in CSF. It may thus be feasible, using this technique, to measure intersubject and intraregional variability in the quantity of Gd-DTPA transferred across the blood-brain barrier after intravenous injection of contrast agent.