Alp Dincer MD, Presenter: Nothing to Disclose

Elif Kosak MD, Abstract Co-Author: Nothing to Disclose

Dilaver Kaya, Abstract Co-Author: Nothing to Disclose

M.Olcay Cizmeli MD, Abstract Co-Author: Nothing to Disclose

Although imaging feature of Hypertrophic Olivary Degeneration have been well described, the dentatorubroolivary pathway has not been characterized with DTI-Fiber Tractography . Our purpose is to demonstrate Guillain-Malloret triangle with DTI and Fiber Tractography both in normal adults and the patients with Hypertrophic Olivary Degenerations.

3T DTI-Fiber tractography were performed in 12 normal adults and 4 patients with hypertrophic olivary degeneration. DTI was performed using a ssEPI sequence (TE=100 ms, TR=10100 ms). A data matrix of a 128 acquisitions,256 mm FOV, 2 mm slice thickness and 2x2x2 mm3 voxel size were used. A total of 60 sections covered the brain without gaps. Diffusion weighting was encoded along 60 independent orientations and b value was 700 mm2/sec. The DTI datasets were processed by using DTI Task Card (The General Hospital Corporation). The eigenvalues and eigenvectors of the diffusion tensor were used to calculate colour coded FA(Fractional anisotropy) maps. The white matter tracts were estimated by using FACT algorithm. ROIs of right and left dentate nucleus, inferior olivary nucleus, central tegmental tract, red nucleus were placed manually by using T2 weighted images, FA maps and colour coded maps according to the region. The avarage FA value in the voxels with in the ROIs were calculated.

Colour coded maps and 3D reconstruction of the datasets showed the dentatorubroolivary pathway in every normal adults. In 4 patients, DTI-Fiber Tractogarphy demonstrated the diseased tract. The FA values of ipsilateral red nucleus/inferior olivary nucleus/central tegmental tract, and contralateral dentate nucleus/superior cerebellar peduncle were decreased significantly compared to other side and normal adults.

DTI-Fiber Tractography can obviously help to shed light on the normal and pathologic Guillain-Mollaret triangle and FA values clearly show not only the changes of inferior olivary nucleus but also the changes of related nucleus and tractus in Hypertrophic Olivary Degeneration.

DTI-Fiber Tractograpy may play an important role in the radiological evaluation and the differential diagnosis of the brain stem degeneratif disorders.

Dincer, A, Kosak, E, Kaya, D, Cizmeli, M, DTI and Fiber Tractograpic Demonstration of Guillain-Malloret Triangle in Normal Adults and the Patients with Hypertrophic Olivary Degeneration.  Radiological Society of North America 2006 Scientific Assembly and Annual Meeting, November 26 - December 1, 2006 ,Chicago IL. http://archive.rsna.org/2006/4429766.html