• 제목/요약/키워드: Magnetic resonance images

검색결과 1,124건 처리시간 0.029초

A Case of Intradural-Extramedullary Form of Primary Spinal Cysticercosis Misdiagnosed as an Arachnoid Cyst

  • Yoo, Minwook;Lee, Chang-Hyun;Kim, Ki-Jeong;Kim, Hyun-Jib
    • Journal of Korean Neurosurgical Society
    • /
    • 제55권4호
    • /
    • pp.226-229
    • /
    • 2014
  • We describe a rare case of intradural-extramedullary primary spinal cysticercosis. A 42-year-old man visited our institute for lower back pain. He denied having consumed raw meet. Magnetic resonance (MR) images revealed an intradural pure cystic mass at the L3-L4 level. A radiologic diagnosis of spinal arachnoid cyst was established. Three years later, he complained of aggravated back pain, and follow-up MR examination showed a markedly expanded cyst, occupying the subarachnoid space from the T11 to the S1 level. L2 hemilaminectomy was performed, and a yellowish infected cyst bulged out through the dural opening. The cyst was removed en bloc. The histopathological findings of the cyst were consistent with parasitic infection. Serum enzyme-linked immunosorbent assay (ELISA) confirmed the presence of spinal cysticercosis. As there was no intracranial lesion, the final diagnosis was primary spinal cysticercosis, which is very rare. MR imaging is a sensitive diagnostic tool for detecting cystic lesions in the spine; however, it is difficult to distinguish cysticercosis from non-infectious cysts such as an arachnoid cyst without using gadolinium enhancement. Clinicians treating spinal cysts with an unusual clinical course should include cysticercosis as a differential diagnosis. We recommend contrast-enhanced MR imaging and serum ELISA in the diagnostic work-up of such cases.

A peripheral tremor associated with intractable pain after traffic accident : case report

  • ;김성호
    • Journal of Yeungnam Medical Science
    • /
    • 제26권1호
    • /
    • pp.74-77
    • /
    • 2009
  • 말초에서부터 야기된 행동장애가 존재하는지 아니면 말초 신경 손상 후의 행동장애가 심리적인 것으로 인한 것인지에 대한 논의가 계속되고 있다. 말초 신경 손상에 의해 야기된 상지의 진전에 대한 증례를 보고하고자 한다. 25세 남자환자는 자동차 사고 이틀 후 상지의 통증과 진전이 발생하였다. 뇌 및 경추의 자기공명영상 촬영상 특이소견이 없었다. 과거력상 특이 소견 없었으며 행동장애에 대한 가족력 또한 없었다. 그는 하루에 약 네 차례에서 여섯 차례 십분 이상 지속되며 악화되는 진전으로 고통 받았다. 약물 치료, 경막외주사 주입, 경추의 신경차단술, 통증유발부위 주사요법 등으로 통증 조절을 하였다. 그 결과 통증이 반 정도 줄었으며 진전의 강도, 시간, 빈도가 줄어들었다.

  • PDF

A feasibility study of using a 3D-printed tumor model scintillator to verify the energy absorbed to a tumor

  • Kim, Tae Hoon;Lee, Sangmin;Kim, Dong Geon;Jeong, Jae Young;Yang, Hye Jeong;Schaarschmidt, Thomas;Choi, Sang Hyoun;Cho, Gyu-Seok;Kim, Yong Kyun;Chung, Hyun-Tai
    • Nuclear Engineering and Technology
    • /
    • 제53권9호
    • /
    • pp.3018-3025
    • /
    • 2021
  • The authors developed a volumetric dosimetry detector system using in-house 3D-printable plastic scintillator resins. Three tumor model scintillators (TMSs) were developed using magnetic resonance images of a tumor. The detector system consisted of a TMS, an optical fiber, a photomultiplier tube, and an electrometer. The background signal, including the Cherenkov lights generated in the optical fiber, was subtracted from the output signal. The system showed 2.1% instability when the TMS was reassembled. The system efficiencies in collecting lights for a given absorbed energy were determined by calibration at a secondary standard dosimetry laboratory (kSSDL) or by calibration using Monte Carlo simulations (ksim). The TMSs were irradiated in a Gamma Knife® IconTM (Elekta AB, Stockholm, Sweden) following a treatment plan. The energies absorbed to the TMSs were measured and compared with a calculated value. While the measured energy determined with kSSDL was (5.84 ± 3.56) % lower than the calculated value, the energy with ksim was (2.00 ± 0.76) % higher. Although the TMS detector system worked reasonably well in measuring the absorbed energy to a tumor, further improvements in the calibration procedure and system stability are needed for the system to be accepted as a quality assurance tool.

핵의학 융합영상의 표준섭취계수 차이에 관한 연구 (Study on the Difference of Standardized Uptake Value in Fusion Image of Nuclear Medicine)

  • 김정수;박찬록
    • 대한방사선기술학회지:방사선기술과학
    • /
    • 제41권6호
    • /
    • pp.553-560
    • /
    • 2018
  • PET-CT and PET-MRI which integrates CT using ionized radiation and MRI using phenomena of magnetic resonance are determined to have the limitation to apply the semi-quantitative index, standardized uptake value (SUV), with the same level due to the fundamental differences of image capturing principle and reorganization, hence, their correlations were analyzed to provide their clinical information. To 30 study subjects maintaining pre-treatment, $^{18}F-FDG$ (5.18 MBq/㎏) was injected and they were scanned continuously without delaying time using $Biograph^{TM}$ mMR 3T (Siemens, Munich) and Biograph mCT 64 (Siemens, Germany), which is an integral type, under the optimized condition except the structural differences of both scanners. Upon the measurement results of $SUV_{max}$ setting volume region of interest with evenly distributed radioactive pharmaceuticals by captured images, $SUV_{max}$ mean values of PET-CT and PET-MRI were $2.94{\pm}0.55$ and $2.45{\pm}0.52$, respectively, and the value of PET-MRI was measured lower by $-20.85{\pm}7.26%$ than that of PET-CT. Also, there was a statistically significant difference in SUVs between two scanners (P<0.001), hence, SUV of PET-CT and PET-MRI cannot express the clinical meanings in the same level. Therefore, in case of the patients who undergo cross follow-up tests with PET-CT and PET-MRI, diagnostic information should be analyzed considering the conditions of SUV differences in both scanners.

Utility of False Profile View for Screening of Ischiofemoral Impingement

  • Kwak, Dae-Kyung;Yang, Ick-Hwan;Kim, Sungjun;Lee, Sang-Chul;Park, Kwan-Kyu;Lee, Woo-Suk
    • Hip & pelvis
    • /
    • 제30권4호
    • /
    • pp.219-225
    • /
    • 2018
  • Purpose: Ischiofemoral impingement (IFI)-primarily diagnosed by magnetic resonance imaging (MRI)-is an easily overlooked disease due to its low incidence. The purpose of this study was to evaluate the usefulness of false profile view as a screening test for IFI. Materials and Methods: Fifty-eight patients diagnosed with IFI between June 2013 and July 2017 were enrolled in this retrospective study. A control group (n=58) with matching propensity scores (age, gender, and body mass index) were also included. Ischiofemoral space (IFS) was measured as the shortest distance between the lateral cortex of the ischium and the medial cortex of lesser trochanter in weight bearing hip anteroposterior (AP) view and false profile view. MRI was used to measure IFS and quadratus femoris space (QFS). The receiver operating characteristics (ROC), area under the ROC curve (AUC) and cutoff point of the IFS were measured by false profile images, and the correlation between the IFS and QFS was analyzed using the MRI scans. Results: In the false profile view and hip AP view, patients with IFI had significantly decreased IFS (P<0.01). In the false profile view, ROC AUC (0.967) was higher than in the hip AP view (0.841). Cutoff value for differential diagnosis of IFI in the false profile view was 10.3 mm (sensitivity, 88.2%; specificity, 88.4%). IFS correlated with IFS (r=0.744) QFS (0.740) in MRI and IFS (0.621) in hip AP view (P<0.01). Conclusion: IFS on false profile view can be used as a screening tool for potential IFI.

삼차신경통 환자의 감마나이프 수술 시 섹터블록 사용의 유용성 평가 (The Usefulness of Sector Blocks in Gamma Knife Surgery with Trigeminal Neuralgia)

  • 정창영;백금문;우성호;김명준;황정호;이현비;김호성
    • 방사선산업학회지
    • /
    • 제12권4호
    • /
    • pp.337-341
    • /
    • 2018
  • Sector block is not used for Gamma Knife surgery in patients with generalized trigeminal neuralgia but sector block is used to reduce the dose reaching the brain stem when the trigeminal ganglgia and the 'Brain stem', radiation sensitive tissue, are adjacent. In the Gamma Knife surgical plan of this study, a surgical plan was established using a Leksell Gamma Plan 11. 1.0 (Elekta Instrument AB, Sweden) with one patient (Block unused, Brain stem dose No volume over 12 Gy, Case 1) who did not need a sector block and four patients (Block unused, Brain stem dose 12 Gy or more, Case 2~5) with a sector block. Magnetic resonance images were obtained by MPRAGE T1 and CISS Respectively. When the trigeminal ganglion is in close proximity to the brain stem, the brain stem volume is decreased when the sector block is used, while the treatment time was increased. In conclusion, This Study evaluates the usefulness of the Sector block in brain stem through Gamma Knife surgery in trigeminal neuralgia, which is considered to be the most important factor for the Gamma Knife surgery.

18F-THK5351 PET Imaging in the Behavioral Variant of Frontotemporal Dementia

  • Nam, Gijin;Jeong, Hye Jin;Kang, Jae Myeong;Lee, Sang-Yoon;Seo, Seongho;Seo, Ha-Eun;Park, Kee Hyung;Yeon, Byeong Kil;Ido, Tatsuo;Shin, Dong Jin;Noh, Young
    • 대한치매학회지
    • /
    • 제17권4호
    • /
    • pp.163-173
    • /
    • 2018
  • Background and Purpose: Behavioral variant frontotemporal dementia (bvFTD) is a subtype of frontotemporal dementia, which has clinical symptoms of progressive personality and behavioral changes with deterioration of social cognition and executive functions. The pathology of bvFTD is known to be tauopathy or TDP-43 equally. We analyzed the $^{18}F-THK5351$ positron emission tomography (PET) scans, which were recently developed tau PET, in patients with clinically-diagnosed bvFTD. Methods: Forty-eight participants, including participants with behavioral variant frontotemporal dementia (bvFTD, n=3), Alzheimer's disease (AD, n=21) and normal cognition (NC, n=24) who completed 3T magnetic resonance images, $^{18}F-THK5351$ PET scans, and detailed neuropsychological tests were included in the study. Voxel-wise statistical analysis and region of interest (ROI)-based analyses were performed to evaluate the retention of THK in bvFTD patients. Results: In the voxel-based and ROI-based analyses, patients with bvFTD showed greater THK retention in the prefrontal, medial frontal, orbitofrontal, anterior cingulate, insula, anterior inferior temporal and striatum regions compared to NC participants. Left-right asymmetry was noted in the bvFTD patients. A patient with extrapyramidal symptoms showed much greater THK retention in the brainstem. Conclusions: The distribution of THK retention in the bvFTD patients was mainly in the frontal, insula, anterior temporal, and striatum regions which are known to be the brain regions corresponding to the clinical symptoms of bvFTD. Our study suggests that $^{18}F-THK5351$ PET imaging could be a supportive tool for diagnosis of bvFTD.

Relationship between rotational disc displacement of the temporomandibular joint and the dentoskeletal morphology

  • Park, So-Hyun;Han, Won-Jeong;Chung, Dong-Hwa;An, Jung-Sub;Ahn, Sug-Joon
    • 대한치과교정학회지
    • /
    • 제51권2호
    • /
    • pp.105-114
    • /
    • 2021
  • Objective: The purpose of this study was to evaluate the relationship between rotational disk displacement (DD) of the temporomandibular joint (TMJ) and the dentoskeletal morphology. Methods: Women aged > 17 years were included in this study. Each subject had a primary complaint of malocclusion and underwent routine cephalometric examinations. They were divided into five groups according to the findings on sagittal and coronal magnetic resonance images of their TMJs: bilateral normal disk position, bilateral anterior DD with reduction (ADDR), bilateral rotational DD with reduction (RDDR), bilateral anterior DD without reduction (ADDNR), and bilateral rotational DD without reduction (RDDNR). Twenty-three cephalometric variables were analyzed, and the Kruskal-Wallis test was used to evaluate differences in the dentoskeletal morphology among the five groups. Results: Patients with TMJ DD exhibited a hyperdivergent pattern with a retrognathic mandible, unlike those with a normal disk position. These specific skeletal characteristics were more severe in patients exhibiting DD without reduction than in those with reduction, regardless of the presence of rotational DD. Rotational DD significantly influenced horizontal and vertical skeletal patterns only in the stage of DD with reduction, and the mandible exhibited a more backward position and rotation in patients with RDDR than in those with ADDR. However, there were no significant dentoskeletal differences between ADDNR and RDDNR. Conclusions: The results of this study suggest that rotational DD of TMJ plays an important role in the dentoskeletal morphology, particularly in patients showing DD with reduction.

Surgical Treatment of Lumbosacral Stenosis Caused by Bacterial Discospondylitis in a Great Dane Dog

  • Yim, Hyeongjun;Kim, Jong-Hoon;Kim, Hyeonjo;Kim, Jieyoo;Lee, Si Eun;Lee, Hee Chun;Kim, Nahyun;Lee, Dongbin;Lee, Jae-Hoon
    • 한국임상수의학회지
    • /
    • 제38권1호
    • /
    • pp.45-48
    • /
    • 2021
  • A 6-year-old, 26 kg spayed female Great Dane presented with back pain and hindlimb paresis. On neurological examination, severe pain was detected on the lumbosacral joint displaying nerve-root signature. The animal presented with lower motor neuron paresis with normal deep pain perception. Radiographic examination revealed narrowing of the lumbosacral joint disc space with endplate destructive lysis. Magnetic resonance imaging of the lumbosacral joint revealed a cauda equina compression, especially on the left. On T2 and T1-weighted images, a mass sized 1 × 1 cm was identified laterally to the left of the lumbosacral joint with hyperintense signal. The lumbosacral joint was stabilized by applying the dorsal distraction fixation-fusion technique and dorsal laminectomy. The soft tissue mass was removed, and a bacterial culture was performed. Coagulase-negative Staphylococcus spp. were detected and discospondylitis was treated with clindamycin for 6 weeks. The patient showed clinical improvement without pain and hindlimb paresis until 6 months follow-up postoperatively.

Boundary-Aware Dual Attention Guided Liver Segment Segmentation Model

  • Jia, Xibin;Qian, Chen;Yang, Zhenghan;Xu, Hui;Han, Xianjun;Ren, Hao;Wu, Xinru;Ma, Boyang;Yang, Dawei;Min, Hong
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • 제16권1호
    • /
    • pp.16-37
    • /
    • 2022
  • Accurate liver segment segmentation based on radiological images is indispensable for the preoperative analysis of liver tumor resection surgery. However, most of the existing segmentation methods are not feasible to be used directly for this task due to the challenge of exact edge prediction with some tiny and slender vessels as its clinical segmentation criterion. To address this problem, we propose a novel deep learning based segmentation model, called Boundary-Aware Dual Attention Liver Segment Segmentation Model (BADA). This model can improve the segmentation accuracy of liver segments with enhancing the edges including the vessels serving as segment boundaries. In our model, the dual gated attention is proposed, which composes of a spatial attention module and a semantic attention module. The spatial attention module enhances the weights of key edge regions by concerning about the salient intensity changes, while the semantic attention amplifies the contribution of filters that can extract more discriminative feature information by weighting the significant convolution channels. Simultaneously, we build a dataset of liver segments including 59 clinic cases with dynamically contrast enhanced MRI(Magnetic Resonance Imaging) of portal vein stage, which annotated by several professional radiologists. Comparing with several state-of-the-art methods and baseline segmentation methods, we achieve the best results on this clinic liver segment segmentation dataset, where Mean Dice, Mean Sensitivity and Mean Positive Predicted Value reach 89.01%, 87.71% and 90.67%, respectively.