MRI techniques: bilateral findings and "normal findings"

Can J Neurol Sci. 2000 May:27 Suppl 1:S35-8; discussion S50-2. doi: 10.1017/s0317167100000627.

Abstract

Magnetic resonance imaging (MRI) techniques allow for significantly better imaging of the temporal lobe compared to computed tomography (CT) or other non-invasive modalities. For detection of foreign tissue lesions, MRI surpasses CT. For the highest non-invasive yield for detection of mesial temporal sclerosis, optimal sequences that should be employed are a heavily T1-weighted volumetric acquisition (to enable both volumetric calculation of hippocampal volume, and, if needed, intracranial volume), T2-weighted coronal sequences, with or without T2-mapping, fluid-attenuated inversion recovery (FLAIR) and, to exclude subtle susceptibility effects from hematoma or cavernoma, gradient echo scans. Magnetic resonance spectroscopy (MRS) may show a decrease in N-acetyl aspartate (NAA) concentration, or NAA: Choline + creatine ratio. Functional MRI is a new and exciting tool that offers the promise of accurately localizing hemispheric functions; its role in the preoperative evaluation of temporal lobe seizures remains uncertain at present.

Publication types

  • Review

MeSH terms

  • Hippocampus / pathology
  • Humans
  • Magnetic Resonance Imaging / methods*
  • Magnetic Resonance Spectroscopy
  • Reference Values
  • Sclerosis / diagnosis
  • Temporal Lobe / pathology*