The anatomy of the perisylvian component of the superior longitudinal fasciculus (SLF) has recently been reviewed by numerous diffusion tensor imaging tractography (DTI) studies. However, little is known about the exact cortical terminations of this tract. The aim of the present work is to isolate the different subcomponents of this tract with fiber dissection and DTI tractography, and to identify the exact cortical connections. Twelve postmortem human hemispheres (6 right and 6 left) were dissected using the cortex-sparing fiber dissection. In addition, three healthy brains were analyzed using DTI-based tractography software. The different components of the perisylvian SLF were isolated and the fibers were followed until the cortical terminations. Three segments of the perisylvian SLF were identified: (1) anterior segment, connecting the supramarginal gyrus and superior temporal gyrus with the precentral gyrus, (2) posterior segment, connecting the posterior portion of the middle temporal gyrus with the angular gyrus, and (3) long segment of the arcuate fasciculus that connects the middle and inferior temporal gyri with the precentral gyrus and posterior portion of the inferior and middle frontal gyri. In the present study, three different components of the perisylvian SLF were identified. For the first time, our dissections revealed that each component was connected to a specific cortical area within the frontal, parietal and temporal lobes. By accurately depicting not only the trajectory but also cortical connections of this bundle, it is possible to develop new insights into the putative functional role of this tract.

Classical fiber dissection of post mortem human brains enables us to isolate a fiber tract by removing the cortex and overlying white matter. In the current work, a modification of the dissection methodology is presented that preserves the cortex and the relationships within the brain during all stages of dissection, i.e. 'cortex-sparing fiber dissection'. Thirty post mortem human hemispheres (15 right side and 15 left side) were dissected using cortex-sparing fiber dissection. Magnetic resonance imaging study of a healthy brain was analyzed using diffusion tensor imaging (DTI)-based tractography software. DTI fiber tract reconstructions were compared with cortex-sparing fiber dissection results. The fibers of the superior longitudinal fasciculus (SLF), inferior frontooccipital fasciculus (IFOF), inferior longitudinal fasciculus (ILF) and uncinate fasciculus (UF) were isolated so as to enable identification of their cortical terminations. Two segments of the SLF were identified: first, an indirect and superficial component composed of a horizontal and vertical segment; and second, a direct and deep component or arcuate fasciculus. The IFOF runs within the insula, temporal stem and sagittal stratum, and connects the frontal operculum with the occipital, parietal and temporo-basal cortex. The UF crosses the limen insulae and connects the orbito-frontal gyri with the anterior temporal lobe. Finally, a portion of the ILF was isolated connecting the fusiform gyrus with the occipital gyri. These results indicate that cortex-sparing fiber dissection facilitates study of the 3D anatomy of human brain tracts, enabling the tracing of fibers to their terminations in the cortex. Consequently, it is an important tool for neurosurgical training and neuroanatomical research.

Deficits in executive and motor functioning in patients with first-episode psychosis are associated with reductions in white matter integrity in the major fasciculi that connect the frontal and temporal cortices as well as in pathways connecting cortical and subcortical regions. Their presence at the onset of illness, in minimally medicated patients, indicates that these findings are not attributable to effects of chronic illness or its treatment.

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Acute stroke services have been installed in most hospitals in the industrialized world, and dealing with hyperacute stroke has become one of the most frequently performed tasks of the on-call radiologist. Imaging plays a key role in current guidelines for thrombolysis, and knowledge of classic early ischemic signs or depiction of hemorrhage at nonenhanced computed tomography (CT) is necessary (although not sufficient) for a satisfactory imaging study. A modern CT examination must also include perfusion CT and CT angiography. Perfusion CT delineates the ischemic tissue (penumbra) by showing increased mean transit time with decreased cerebral blood flow (CBF) and normal or increased cerebral blood volume (CBV), whereas infarcted tissue manifests with markedly decreased CBF and decreased CBV. CT angiography can depict the occlusion site, help grade collateral blood flow, and help characterize carotid atherosclerotic disease. A complete CT study (nonenhanced CT, perfusion CT, and CT angiography) may be performed and analyzed rapidly and easily by general radiologists using a simple standardized protocol and may even facilitate diagnosis by less experienced radiologists in affected patients.

The TPFIA is a critical neural crossroad; it is traversed by 7 white matter tracts that connect multiple areas of the ipsilateral and contralateral hemisphere. It is also a vulnerable part of the network in that a lesion within this area will produce multiple disconnections. This is valuable information when a surgical approach through the parieto-temporo-occipital junction is planned. To decrease surgical risks, a detailed diffusion tensor imaging tractography reconstruction of the TPFIA should be performed, and intraoperative electric stimulation should be strongly considered.

Computed tomography (CT)-guided biopsy of the spine is considered a safe, accurate, and relatively inexpensive examination technique. Our purpose was to determine the diagnostic accuracy of CT-guided biopsies exclusively for vertebral osteomyelitis. A retrospective study was performed from a consecutive series of 72 patients with confirmed vertebral osteomyelitis with 46 CT-guided biopsies performed in 40 patients. Biopsy specimens were sent for bacteriologic and cytologic analysis. An adequate specimen for microbiologic examination was not obtained in one case and not enough sample for additional pathologic examination in 17 cases. The mean age of patients was 58 years, with a range of 1-88 years, including 24 men and 16 women. The level of spinal biopsy was thoracic in 18 (40%) and lumbar in 28 (60%). The analysis revealed the infection agent in 20 cases (43% sensitivity). Diagnostic rates obtained in patients with previous antibiotic treatment were significantly lower (23% vs. 60%, p = 0.013). Computed tomography-guided fine-needle aspiration biopsy is an important tool in the diagnostic evaluation of vertebral osteomyelitis. However, this technique yields a lower diagnostic rate than previously reported biopsy of neoplastic vertebral lesions, especially if performed in patients with previous antibiotic treatment.

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