• Title/Summary/Keyword: Diffusion Tensor Imaging

Search Result 108, Processing Time 0.036 seconds

Delayed Anoxic Encephalopathy after Carbon Monoxide Poisoning: Evaluation of Therapeutic Effect by Serial Diffusion-Tensor Magnetic Resonance Imaging and Neurocognitive Test (일산화탄소중독 이후 발생한 지연무산소뇌병증: 확산텐서영상 및 신경인지기능검사를 이용한 치료 효과의 평가)

  • Ryu, Ho-Sung;Kim, Youngwook;Jung, Boo-Kyoung;Kim, Yong-Won
    • Journal of the Korean neurological association
    • /
    • v.36 no.4
    • /
    • pp.358-362
    • /
    • 2018
  • Delayed anoxic encephalopathy after carbon monoxide (CO) poisoning is characterized by neurological deterioration that occurs after recovery from acute CO intoxication. There has been no established therapy. We report a patient recovered from acute CO intoxication developed various neurological symptoms. After the administration of high dose prednisolone and anticholinesterase inhibitor, the therapeutic effect was remarkable and confirmed by quantitative analysis of diffusion-tensor imaging (DTI). DTI could be used to evaluate the therapeutic effect for delayed anoxic encephalopathy after CO poisoning.

Brain Mapping Using Neuroimaging

  • Tae, Woo-Suk;Kang, Shin-Hyuk;Ham, Byung-Joo;Kim, Byung-Jo;Pyun, Sung-Bom
    • Applied Microscopy
    • /
    • v.46 no.4
    • /
    • pp.179-183
    • /
    • 2016
  • Mapping brain structural and functional connections through the whole brain is essential for understanding brain mechanisms and the physiological bases of brain diseases. Although region specific structural or functional deficits cause brain diseases, the changes of interregional connections could also be important factors of brain diseases. This review will introduce common neuroimaging modalities, including structural magnetic resonance imaging (MRI), functional MRI (fMRI), diffusion tensor imaging, and other recent neuroimaging analyses methods, such as voxel-based morphometry, cortical thickness analysis, local gyrification index, and shape analysis for structural imaging. Tract-Based Spatial Statistics, TRActs Constrained by UnderLying Anatomy for diffusion MRI, and independent component analysis for fMRI also will also be introduced.

Wallerian Degeneration of Insufficiently Affected White Matters in Old Infarction: Tract of Interest Analysis of Diffusion Tensor Imaging

  • Choi, Chi-Hoon;Lee, Jong-Min;Koo, Bang-Bon;Park, Jun-Sung;Kwon, Jun-Soo;Kim, Sun-I.
    • Journal of Biomedical Engineering Research
    • /
    • v.28 no.3
    • /
    • pp.317-324
    • /
    • 2007
  • The application of diffusion tensor imaging (DTI) and fiber tractography to Wallerian degeneration (WD) is important because this technique is a very potent tools for quantitatively evaluating fiber tracts in vivo brain. We analyzed a case and control using tracts of interest (TOI) analysis to quantify WD. We scanned a case of old infarction and an age-matched healthy volunteer. T1 magnetization prepared rapid acquisition gradient echo (MPRAGE), fluid attenuated inversion recovery (FLAIR) and 12-direction diffusion tensor imaging (DTI) were obtained and analyzed using TOI analysis. The value of mean diffusity ($D_{av}$) and fracional anisotrophy (FA) were analyzed statistically by MWU test. A p-value of less than 0.05 was considered to indicate statistical significance. A comparison of the global fiber diffusion characteristics shows WD of both the corpus callosum and the ipsilateral superior longitudinal fasciculus. The corpus callosum in particular showed trans-hemispherical degeneration. Local fiber characteristics along the geodesic paths show WD in the corpus callosum, ipsilateral superior longitudinal fasciculus, ipsilateral corticospinal tract, and ipsilateral corticothalamic tract. We have demonstrated changes in $D_{av}$ and FA values and a clear correspondence with the WD in various tracts. TOI analysis successfully revealed radial WD in white matter tracts from a region of encephalomalacia and primary gliosis, although they were only slightly affected.

Preoperative Weakness and Demyelination of the Corticospinal Tract in Meningioma Patients : Changes in Diffusion Parameters Using Diffusion Tensor Imaging

  • Kim, Myoung Soo;Chung, Chun Kee;Jung, Hee-Won;Park, Chul-Kee;Kim, Chi Heon;Kim, June Sic
    • Journal of Korean Neurosurgical Society
    • /
    • v.55 no.5
    • /
    • pp.267-272
    • /
    • 2014
  • Objective : Differentiation of demyelination in white matter from axonal damage can be determined using diffusion tensor imaging (DTI). In this study using meningioma patients an attempt was made to evaluate the relationship between preoperative weakness and the changes of diffusion parameters in the corticospinal tract (CST) using DTI. Methods : Twenty-six patients with meningioma were enrolled in this study. Eleven of them suffered from objective motor weakness and were classified as Group 1. The remaining 15 patients did not present motor weakness and were classified as Group 2. Fiber tractography and CST diffusion parameters were obtained using DTIStudio. The ratios (lesion side mean value/contralateral side mean value) of CST diffusion parameters were compared with 1.0 as a test value using a one-sample t-test. Results : In Group 1, fractional anisotropy (FA), tensor trace (TT), and radial diffusivity (RD, ${\lambda}2$ and ${\lambda}3$) of the CST were significantly different between two hemispheres, but axial diffusivity (AD, ${\lambda}1$) of the CST was not significantly different between two hemispheres. In Group 2, FA and ${\lambda}3$ of CST did not differ significantly between the hemispheres. In Group 2, TT, ${\lambda}1$, and ${\lambda}2$ of CST in the ipsilateral hemisphere were significantly higher than those of the unaffected hemisphere. However, the differences were small. Conclusion : Motor weakness was related to a low FA and high TT resulting from increased RD of the CST fibers. CST diffusion changes in patients with weakness are similar to those for demyelination.

Diffusion Tensor MRI and Fiber Tractography: Evaluation of Developmental CNS Anomaly: Preliminary Results

  • Lee, Seung-Koo;Kim, Dong-Ik
    • Proceedings of the KSMRM Conference
    • /
    • 2002.11a
    • /
    • pp.86-86
    • /
    • 2002
  • Purpose: To evaluate the white matter fiber configuration in various developmental CNS anomaly 대상 및 방법: Jubert Syndrome, congenital schizencephaly, callosal agenesis and hemiplegic cerebral palsy patients were evaluated by diffusion tensor MRI. All studies were performed using a 1.5T Philips Gyroscan Intern system. Diffusion weighted imaging was performed using single-shot echo planar imaging, with navigator echo phase correction and SENSE. Diffusion weighting was performed along six independent axes, using diffusion weighting of b=600s/$\textrm{mm}^2$. 128 matrix/zero filled to 256, 23cm FOV, 3mm slice thickness were used for imaging parameters. Data were processed on a Window-2000 PC equipped with IDL and PRIDE (Philips Medical System).

  • PDF

Comparison of in SENSE and Multiband SENSE technique of the Diffusion tensor using Parallel Imaging (병렬 기법과 다중대역병렬기법간의 유용성 비교)

  • Lee, Ho-Beom;Son, Soon-Yong
    • Proceedings of the Korea Contents Association Conference
    • /
    • 2018.05a
    • /
    • pp.61-62
    • /
    • 2018
  • DTI (Diffusion Tensor Imaging)에서는 임상적으로 매우 중요하나 긴 획득시간으로 인하여 적용에 어려움이 있었다. 그러나 최근에 개발된 다중대역병렬기법 (Multiband SENSE)은 동시에 여러 개의 절편을 획득이 가능한 기법으로 기존에 사용되는 병렬기법(SENSE)과 비교하여도 매우 유용한 것을 알 수 있다.

  • PDF

Gamma Knife Radiosurgery for Trigeminal Neuralgia : Review and Update

  • Lee, Seunghoon;Lee, Jung-Il
    • Journal of Korean Neurosurgical Society
    • /
    • v.65 no.5
    • /
    • pp.633-639
    • /
    • 2022
  • Accurate diagnosis of trigeminal neuralgia (TN) is the starting point for optimal treatment. Gamma knife radiosurgery (GKRS) is currently regarded as one of the first-line treatment options for medically refractory TN. GKRS is a less invasive treatment with a low risk of complications than other surgical procedures that provides a favorable pain control Barrow Neurological Institute (BNI) I-IIIb rate of >75% at short-term follow-up. Drawbacks of GKRS include the latency period before pain relief and higher recurrence rate compared with microvascular decompression. Therefore, repeat treatment is necessary if the initial GKRS was effective but followed by recurrence. The concept of dose rate and the biologically effective dose of radiation has been actively studied in radiation oncology and is also applied in GKRS for TN to achieve high safety and efficacy by prescribing the optimal dose. Recent progress in functional imaging, such as diffusion tensor imaging, enables us to understand the pathophysiology of TN and predict the clinical outcome after GKRS. Here, we review TN, GKRS, and recent updates, especially in the concepts of radiation dose, diffusion tensor imaging studies, and repeat treatment in GKRS for TN.

A Study on the Characteristics of Plant Fiber Materials for Diffusion Tensor Imaging Phantom (확산텐서영상 팬텀 제작을 위한 식물섬유 재료의 특성에 관한 연구)

  • Lee, Jung-Hoon
    • Journal of radiological science and technology
    • /
    • v.43 no.6
    • /
    • pp.475-480
    • /
    • 2020
  • The purpose of this study was to reconstruct diffusion tensor tractography (DTT) using stem of garlic and asparagus for in vitro phantom of diffusion tensor imaging (DTI), and to compare and evaluate the fractional anisotropy (FA) value and the apparent diffusion coefficient (ADC) value to determine whether it can be used as materials for in vitro phantoms. Among various plant fibers such as stem of garlic, palmae, cotton, asparagus, etc., stem of garlic and asparagus, which are considered to be the most suitable for making phantoms, and whose shape is considered to be the most suitable for making phantoms, were selected and tests were conducted. Holes were made in a plastic bucket at an angle of 0°, 30°, 60°, 90°, and 120°, then tubes were inserted. In the tube, asparagus and stem of garlic were inserted as far in as possible, and the inserted tube was inserted into the center of the heat bathed gelatin to harden. We were able to reproduce DTT images in asparagus and stem of garlic. Fiber tissues of asparagus and stem of garlic did not show complete connectivity, but the reconstructed images of DTT showed good connectivity. The FA values of asparagus in the tubes were 0.198 at 0° (straight), 0.207 at 30°, 0.187 at 60°, 0.231 at 90°, and 0.204 at 120°. In addition, the FA values of stem of garlic in the tubes were 0.235 at 0°, 0.236 at 30°, 0.216 at 60°, 0.218 at 90°, and 0.257 at 120°. The ADC values of asparagus in the tubes were 1.545 at 0°, 1.677 at 30°, 1.629 at 60°, 1.535 at 90°, and 1.725 at 120°. In addition, the ADC values of stem of garlic in the tubes were 1.252 at 0°, 1.396 at 30°, 1.698 at 60°, 1.756 at 90°, and 1.466 at 120°. For the best expressed DTT reconstruction image, it showed the longest connectivity in the straight line as we hypothesized. In addition, when comparing the FA values and ADC values of fiber tissues of stem of garlic and asparagus, FA value was generally higher in stem of garlic and ADC value was slightly higher in asparagus.

Gait Characteristic in a Stroke Patient with an Intact Corticospinal Tract and Corticoreticular Pathway: A Case Study

  • Yeo, Sang Seok;Cho, In Hee
    • The Journal of Korean Physical Therapy
    • /
    • v.30 no.2
    • /
    • pp.73-77
    • /
    • 2018
  • Purpose: The prefrontal lobe, supplementary motor area, cerebellum, and basal ganglia are activated during gait. In addition, gait is controlled by nerves, such as the corticospinal tract (CST) and corticoreticular pathway (CRP). In this study, the presence of an injury to the CST and CRP was identified by diffusion tensor imaging and the characteristics of the gait pattern were investigated according to inferior cerebral artery infarction. Methods: One patient and six control subjects of a similar age participated. A 69-year-old female patient had an injury to the left basal ganglia, insular gyrus, corona radiata, dorsolateral prefrontal cortex, and postcentral gyrus due to an inferior cerebral artery infarction. Diffusion tensor imaging (DTI) data was acquired 4 weeks after the stroke. The kinematic and spatio-temporal parameters of gait were collected using a three-dimensional gait analysis system. Results: On 4 weeks DTI, the CST and CRP in the affected hemisphere did not show injury to the affected and unaffected hemisphere. Gait analysis showed that the cadence of spatio-temporal parameter was decreased significantly in the patient. The angle of the knee joint was decreased significantly in the affected and unaffected sides compared to the control group. Conclusion: The results of diffusion tensor imaging showed that although the patient was evaluated to be capable of an independent gait, the quality and quantity of gait might be reduced. This study could help better understand the gait ability analysis of stroke patients and the abnormal gait pattern of patients with a brain injury.