Thomas Ostergard BS, MS, Presenter: Nothing to Disclose

Zachary B. Love MD, Abstract Co-Author: Nothing to Disclose

Charles F. Lanzieri MD, Abstract Co-Author: Nothing to Disclose

Robert J Maciunas, Abstract Co-Author: Research support, Medtronic, Inc Research support, BrainLAB AG

To compare fluid-attenuated inversion-recovery sequence (FLAIR) imaging prior to and after the administration of contrast agent in the diagnosis of hippocampal sclerosis (HS).

Reviewers assessed FLAIR images before and after the administration of Gadolinium in 14 patients with medication-refractory, EEG-confirmed temporal lobe epilepsy. Regions of interest were created to record the signal intensity from the hippocampus and amygdala on each image. Images were scored for radiologic markers of hippocampal sclerosis (hippocampal volume asymmetry, hippocampal hyperintensity, amygdalar volume asymmetry, amygdalar hyperintensity, other temporal lobe hyperintensity, and temporal horn enlargement). Raters also scored their confidence in diagnosing HS on a 0-3 point scale. Quantitative and qualitative data from the epileptogenic hemisphere were compared to those of the contralateral hemisphere.

When compared to pre-contrast images, contrast administration resulted in a relative increase (3.1% ± 0.8% ) in the intensity of the hippocampus ipsilateral to the epileptogenic focus. Contrast administration also increased the signal intensity in the contralateral hippocampus (0.5% ± 0.2%) to a much smaller degree. However, this selective enhancement did not translate into a significant difference between the epileptogenic and contralateral hemispheres. The average reported confidence in HS diagnosis was higher without contrast agent than with contrast agent (2.00 ± 0.07 vs. 1.85 ± 0.08), however this difference was not statistically significant. No other significant differences were found between qualitative or quantitative variables.

The addition of contrast agent neither aids nor impairs the use of FLAIR imaging in the diagnosis of hippocampal sclerosis.

Contrast enhanced FLAIR may provide diagnostic utility in other pathologies of the temporal lobe, most notably dysembryoplastic neuroepithelial tumors.

Ostergard, T, Love, Z, Lanzieri, C, Maciunas, R, Contrast-enhanced Fluid Attenuated Inversion Recovery (FLAIR) Sequence Imaging in the Diagnosis of Temporal Lobe Epilepsy.  Radiological Society of North America 2010 Scientific Assembly and Annual Meeting, November 28 - December 3, 2010 ,Chicago IL. http://archive.rsna.org/2010/9013011.html