Three‐dimensional (3D) visualization of endolymphatic hydrops after intratympanic injection of Gd‐DTPA: Optimization of a 3D‐real inversion‐recovery turbo spin‐echo (TSE) sequence and application of a 32‐channel head coil at 3T

Abstract

To enable volume visualization of endolymphatic hydrops of Ménière's disease via a volume rendering (VR) technique, a three-dimensional (3D) inversion-recovery (IR) sequence with real reconstruction (3D-real IR) sequence after intratympanic injection of Gd-DTPA was optimized for higher spatial resolution using a 32-channel head coil at 3T. Pulse sequence parameters were optimized using a diluted Gd-DTPA phantom. Then, 11 patients who had been clinically diagnosed with Ménière's disease and a patient with sudden hearing loss were scanned. Images were processed using commercially available 3D-VR software. 3D-real IR data was processed to produce endolymph and perilymph fluid volume images in different colors. 3D-CISS data was processed to generate total fluid volume images. While maintaining a comparable signal-to-noise ratio (SNR) and scan time, the voxel volume could be reduced from 0.4 x 0.4 x 2 mm(3) with a 12-channel coil to 0.4 x 0.4 x 0.8 mm(3) with a 32-channel coil. A newly-optimized protocol allowed the smooth, three-dimensional visualization of endolymphatic hydrops in all patients with Ménière's disease. Volumetrically separate visualization of endo-/perilymphatic space is now feasible in patients with Ménière's disease using an optimized 3D-real IR sequence, a 32-channel head coil, at 3T, after intratympanic administration of Gd-DTPA. This will aid the understanding of the pathophysiology of Ménière's disease.