Compartmental study of T1 and T2 in rat brain and trigeminal nerve in vivo

Abstract

The integrated T1-T2 characteristics of rat brain and trigeminal nerve water were studied in vivo using a rapid method for acquiring a series of images that depend on T1 and T2 relaxation times. Gray matter regions showed only one signal component in both the T1 and T2 domains. Trigeminal nerve, however, which has been shown previously to exhibit three T2 components, was found to also exhibit three T1 components. The correlations between these T1 and T2 components were demonstrated by uniquely filtering out each of the three T2 components using an inversion-recovery preparation, as determined by the component T1 values. Based on previous works, it is postulated that each of these three signal components is derived from a unique microanatomical region of the nerve. Knowledge of these T1 components may thus prove valuable in devising novel methods of identifying the presence and quantifying the volume of tissue subtypes such as myelin. © 2002 Wail-Liss, Inc.