الفهرس 
DTI anatomy of brain white matter tractsOnly 14 pages are availabe for public view
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Abstract
Functional MRI is a relatively new noninvasive brain imaging technique that has been used for neuroscience research applications since the early 1990s. This technique relies on the blood oxygenation level dependent (BOLD) effect, which was first described by Dr. Ogawa and colleagues in 1990.
Diffusion tensor magnetic resonance imaging (DTI) is a noninvasive technique that can be used to assess the integrity of cerebral tissue.
Brain surgery is an effective treatment for individuals who suffer from medically intractable epilepsy. One common surgical procedure for epilepsy is anterior temporal lobectomy (ATL), which produces long-term cure rates of approximately 60–80%. Common complications of ATL include upper quadrant visual field defects, impairments on naming and other language tasks, and declarative memory deficits. Thus it has become part of presurgical work-up in potential patients to weigh the risk of memory decline against the chance of seizure relief. The key to estimating the risk of memory decline after surgery is the preoperative assessment of the functional integrity of the tissue to be resected.
Aim of the work:
To demonstrate the role of fMRI and MR tractography as qualitative and quantitative tools for:
1. Delineation of memory functions in cases of partial epilepsy candidates for surgery and correlating it to the cognitive test.
2. Language lateralization and localization in partial epilepsy cases candidates for surgery.
For proper detection of promising partial epilepsy patients who are candidates for surgery.
Material and methods: Sixteen patients known to have refractory epilepsy were evaluated. We did fMRI for language and memory areas for localization and lateralization of the dominating cortical areas concerned with language and memory. Diffusion-weighted images along twelve different directions with a b value of 1000 s/mm2. A 1.5-T scanner was used to acquire those examinations. For DTI we compared the mean diffusivity (MD) and fractional anisotropy (FA) from symmetrical voxels by sampling the basal ganglia, thalamus, hippocampus and parahippocampus regions bilaterally. We compared measurements with the EEG, high-resolution MR imaging, as well as clinical data. For MR tractography, various tracts were traced including the Meyer’s loop.
Results: Among the study group only 5 patients with partial epilepsy out of 16 are promising candidates for surgery representing only 31.25 % among the study population 68.75% of our study population were excluded according to our quantitative and qualitative tools.
In conclusion: Combined fMRI with MR tractography are valuable qualitative and quantitative tools for proper localization and lateralization of the eloquent areas including memory, language areas and Meyer’s loop in the selection of promising epilepsy surgery candidates and for pre-operative planning.