Two technical challenges must be overcome before brain fiber tracking with diffusion-tensor magnetic resonance (MR) imaging can be applied to clinical practice: Imaging time must be shortened, and image distortion must be minimized. Single-shot echo-planar MR imaging with parallel imaging technique enabled both objectives to be accomplished. Twenty-three consecutive patients with brain tumors underwent MR imaging with a 1.5-T whole-body MR system. Fiber tracts on the lesion side in the brain had varying degrees of displacement or disruption as a result of the tumor. Tract disruption resulted from direct tumor involvement, compression on the tract, and vasogenic edema surrounding the tumor. This diffusion-tensor MR imaging method with the parallel imaging technique allows clinically feasible brain fiber tracking.

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The balance between heat production (metabolism) and heat removal (blood flow) helps in keeping the temperature of the brain constant. In patients with moyamoya disease, this balance may be disturbed. The purpose of this study was to assess the thermal pathophysiology of the brain in patients with moyamoya disease. The study included 12 consecutive patients with moyamoya disease and 10 controls. Temperature was measured by image postprocessing of diffusion-weighted images. Our noninvasive thermometry showed that the ventricular temperature of moyamoya disease patients was higher than that of normal controls. The mean temperature difference of 1.1 degrees C between the two groups was significant. Patients with moyamoya disease tend to have elevated ventricular temperatures, which may represent a mismatch between cerebral metabolism and perfusion.

BACKGROUND AND PURPOSE:The purpose of this work was to test the feasibility of using high angular resolution diffusion imaging (HARDI)-based multitensor tractography to depict motor pathways in patients with brain tumors.

A 71-year-old male presented with multiple central nervous system tuberculomas including spinal intramedullary tuberculoma manifesting as occipitalgia and left hemiparesis. He had received medical treatment for lung and testis tuberculosis. Magnetic resonance imaging revealed an intramedullary lesion at the C-2 level as well as multiple small extramedullary and intracranial lesions. His neurological symptoms gradually worsened despite intensive antituberculous therapy. The C-2 intramedullary lesion responsible for left hemiparesis was surgically extirpated. Postoperatively, his neurological symptoms improved gradually, and no recurrence was evident at the resected site. Surgical intervention is mandatory in patients with intramedullary tuberculoma if neurological symptoms deteriorate or lesions enlarge despite continuous antituberculous therapy.