No abstract available.
Pyramidal Tracts*

Diffusion tensor tractorgraphy which is based on line propagation method with brute force approach is implemented and the vector correlation function is proposed in addition to the conventional fractional anisotrophy value as a criterion to select seed points. For the whole tractography, the proposed method used 41% less seed points than the conventional brute force approach for FA > or =0.3 and most of the fiber tracks in the outer region of white matter were removed. For the corticospinal tract passing through region of interest, the proposed method has produced similar results with 50% less seed points than conventional one.
Diffusion ; Pyramidal Tracts

According to the anatomical pathways of the corticobulbar tract, it is known that the responsible lesion site of central facial palsy is at the level of the midpons or the more rostral portion. In rare cases, central facial palsy is found in medullary lesions. We report two cases of medullary infarctions which presented as central facial palsy. These cases suggested that the hypothesis that part of the pathway of the facial corticobulbar fibers descend ipsilaterally to the lower medulla before decussating and ascending contralaterally to the facial nucleus.
Facial Paralysis* ; Infarction* ; Pyramidal Tracts

No abstract available.
Brain ; Muscle Spasticity ; Paraparesis, Spastic ; Pyramidal Tracts

PURPOSE: Diffusion tensor imaging (DTI) data must be analyzed by an analyzer after data processing. Hence, the analyzed data of DTI might depend on the analyzer, making it a major limitation. This paper reviewed previous DTI studies reporting the repeatability and reproducibility of data from the corticospinal tract (CST), one of the most actively researched neural tracts on this topic. MATERIALS AND METHODS: Relevant studies published between January 1990 and December 2018 were identified by searching PubMed, Google Scholar, and MEDLINE electronic databases using the following keywords: DTI, diffusion tensor tractography, reliability, repeatability, reproducibility, and CST. As a result, 15 studies were selected. RESULTS: Measurements of the CSTs using region of interest methods on 2-dimensional DTI images generally showed excellent repeatability and reproducibility of more than 0.8 but high variability (0.29 to 1.00) between studies. In contrast, measurements of the CST using the 3-dimensional DTT method not only revealed excellent repeatability and reproducibility of more than 0.9 but also low variability (repeatability, 0.88 to 1.00; reproducibility, 0.82 to 0.99) between studies. CONCLUSION: Both 2-dimensional DTI and 3-dimensional DTT methods appeared to be reliable for measuring the CST but the 3-dimensional DTT method appeared to be more reliable.
Diffusion Tensor Imaging ; Diffusion ; Methods ; Pyramidal Tracts

No abstract available.
Diffusion ; Leukoencephalopathies ; Pyramidal Tracts ; Sepsis ; Sepsis-Associated Encephalopathy

Opalski syndrome is a rare lateral medullary infarction variant presenting with ipsilateral motor deficits known to be caused by involvement of the post-decussating pyramidal tract. Here, we report two rare cases of Opalski syndrome presenting as ipsilateral sensorimotor deficits in cerebral infarction.
Cerebral Infarction ; Infarction ; Lateral Medullary Syndrome ; Pyramidal Tracts

We report the clinical usefulness of elucidating the state of the corticospinal tract (CST) by the use of diffusion tensor image tractography (DTT) in hemiparetic stroke patients. DTT was performed using 1.5 T magnetic resonance imaging. DTT demonstrated that the CST of the affected hemisphere was preserved in the medial portion of the hematoma in patient 1, but was interrupted by a hematoma in patient 2. DTT seems to be useful for elucidating the status of the CST in hemiparetic stroke patients.
Diffusion ; Hematoma ; Humans ; Magnetic Resonance Imaging ; Pyramidal Tracts ; Stroke

Osmotic myelinolysis is a distinctive clinical syndrome with a characteristic "bat wing" MRI lesion in the central pons, which is also called central pontine myelinolysis (CPM). However, demyelinating lesions are not only limited to the central pons, but also may be involved in the extrapontine regions including the basal ganglia, thalamus, and cerebellum (extrapontine myelinolysis; EPM). We report an atypical case of osmotic myelinolysis confined to the pyramidal tract from the precentral gyrus to the central pons via the corona radiata and internal capsule in a MR image.
Basal Ganglia ; Cerebellum ; Internal Capsule ; Magnetic Resonance Imaging ; Myelinolysis, Central Pontine ; Pons* ; Pyramidal Tracts* ; Thalamus

Authors analysed 25 cases of the narrow spinal canal in cervical and lumbar region, who admitted to the Catholic Medical Center, Seoul from Jan. 1970 to August 1976. Correlation between neurologic feature and radiologic finding was attempted and compared the measurements of narrow cervical and lumbar spinal canal with that of the healthy Korean. The mean anterioposterior diameter of the cervical canal in healthy Korean was 16.2mm at C4, 16.4mm. at C5, 16.6mm. at C6, and 16.4mm. at C7. The ratio of canal to vertebral body in the plain lumbar spine was 1 : 3.9 at L3, 1 : 3.8 at L4 and 1 : 3.8 at L5. The measurements of 25 cases of narrow spinal canal were significantly reduced comparing with the healthy one. The clinical symptoms were closely related to the severity of the narrow spinal canal while there was intermittent or insidious course of symptom in the group of mild narrow spinal canal. Symptom of root compression or neurogenic claudication is frequent manifestation in the severe narrow spinal canal. and the symptom is correlated to the severity of the narrowing. Urinary disturbance and pyramidal tract sign were evident in the cervical narrow canal. The characteristic myelographic feature was multiple constrictive defect at the level of the narrow canal. Common findings in laminectomy were the thickened laminae and hypertrophied ligamentum flavum in the narrow canal. Herniated disc was not found but in one case in the cervical narrow canal at surgery. The recovery of the symptom was better in the group of the narrow canal who had mild degree of narrowing or who had the symptom in short duration rather than prolonged course.
Intervertebral Disc Displacement ; Laminectomy ; Ligamentum Flavum ; Lumbosacral Region ; Pyramidal Tracts ; Seoul ; Spinal Canal* ; Spine