Juergen Lutz MD, Presenter: Nothing to Disclose

Robert Stahl MD, Abstract Co-Author: Nothing to Disclose

Holger Frank Boehm MD, Abstract Co-Author: Nothing to Disclose

Olaf Dietrich, Abstract Co-Author: Nothing to Disclose

Martin John Hempel, Abstract Co-Author: Nothing to Disclose

Maximilian F. Reiser MD, Abstract Co-Author: Nothing to Disclose

Lorenz Jaeger MD, PhD, Abstract Co-Author: Nothing to Disclose

et al, Abstract Co-Author: Nothing to Disclose

Many challenges and efforts have been performed in neuroimaging to understand the complex auditory disorder in tinnitus. There is considerably evidence that microstructural neuroplasticity changes due to increased neural activity in parts of the acoustic pathway cause tinnitus. Diffusion Tensor Imaging (DTI) was used to investigate micro structural pathways of the acoustic pathway in patients with longstanding tinnitus. Aim of the study was to compare the quantitative DTI indices of patients with tinnitus and controls.

  12 patients (mean age 38.5 years) and 12 healthy volunteers (mean age 35.3 years) were examined using an 1,5 T MR System (Magnetom AVANTO, Siemens) with T1-weighted sequence (MPRAGE-Sequence, 1.1x1.1x1.1 mm ) and DTI EPI-sequence (TE 71ms, TR 6000ms, 36 slices, 1.8x1.8x3.6 mm spatial distribution). Lateral lemniscus, inferior colliculus, medial geniculate body, auditory radiation, superficial temporal gyrus and transverse temporal gyrus were evaluated. The fractional anisotropy (FA) and the apparent diffusion coefficient (ADC) were studied.

The ADC values were reduced and FA increased significantly (p<0.05) in the inferior colliculus and the lateral lemniscus in the tinnitus patients in comparison to the controls on the opposite side. However, there were no significant differences in FA and ADC bilateral in the auditory radiation, the superficial temporal gyrus and the transvers temporal gyrus.   

Our study provides preliminary data suggesting a possible lateralized involvement of sub cortical structures in tinnitus patients compared to healthy subjects. Tinnitus is accompanied with an increase in anisotropy (FA) mainly in the inferior colliculus. These findings suggest evidence of underlying microstructural detectable changes in parts of the acoustic pathway in patients with tinnitus.

DTI could be used for the deeper understanding of disturbance of complex microstructural changes as well as a possible imaging tool for treatment response and monitoring.   

Lutz, J, Stahl, R, Boehm, H, Dietrich, O, Hempel, M, Reiser, M, Jaeger, L, et al, , Diffusion Tensor Imaging (DTI) of the Central Auditory Pathway in Patients with Longstanding Unilateral Tinnitus.  Radiological Society of North America 2008 Scientific Assembly and Annual Meeting, February 18 - February 20, 2008 ,Chicago IL. http://archive.rsna.org/2008/6013221.html