• Title/Summary/Keyword: Computed tomography imaging

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Vascular ring anomaly with a right patent ductus arteriosus and a left aortic arch in a juvenile cat

  • Aki Takeuchi ;Kazumi Shimada ;Lina Hamabe ;Tomohiko Yoshida;Yusuke Ozai ;Miki Hirose ;Aimi Yokoi ;Momoko Watanabe ;Ikki Mitsui ;Ryou Tanaka
    • Journal of Veterinary Science
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    • 제24권4호
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    • pp.50.1-50.6
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    • 2023
  • This paper reports the clinical findings and surgical treatment of feline right patent ductus arteriosus (RPDA) with a left aortic arch. A two-month-old female Maine Coon was referred for an investigation of regurgitation after weaning. RPDA with a left aortic arch was diagnosed based on the echocardiographic and computed tomography (CT) findings. A right-fourth intercostal thoracotomy was found to be an appropriate approach to the duct. Preoperative diagnosis is crucial and diagnostic imaging, including radiography, echocardiography, and cardiac CT examination, is essential for determining if the aortic arch is right or left.

A Comprehensive Analysis of Deformable Image Registration Methods for CT Imaging

  • Kang Houn Lee;Young Nam Kang
    • 대한의용생체공학회:의공학회지
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    • 제44권5호
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    • pp.303-314
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    • 2023
  • This study aimed to assess the practical feasibility of advanced deformable image registration (DIR) algorithms in radiotherapy by employing two distinct datasets. The first dataset included 14 4D lung CT scans and 31 head and neck CT scans. In the 4D lung CT dataset, we employed the DIR algorithm to register organs at risk and tumors based on respiratory phases. The second dataset comprised pre-, mid-, and post-treatment CT images of the head and neck region, along with organ at risk and tumor delineations. These images underwent registration using the DIR algorithm, and Dice similarity coefficients (DSCs) were compared. In the 4D lung CT dataset, registration accuracy was evaluated for the spinal cord, lung, lung nodules, esophagus, and tumors. The average DSCs for the non-learning-based SyN and NiftyReg algorithms were 0.92±0.07 and 0.88±0.09, respectively. Deep learning methods, namely Voxelmorph, Cyclemorph, and Transmorph, achieved average DSCs of 0.90±0.07, 0.91±0.04, and 0.89±0.05, respectively. For the head and neck CT dataset, the average DSCs for SyN and NiftyReg were 0.82±0.04 and 0.79±0.05, respectively, while Voxelmorph, Cyclemorph, and Transmorph showed average DSCs of 0.80±0.08, 0.78±0.11, and 0.78±0.09, respectively. Additionally, the deep learning DIR algorithms demonstrated faster transformation times compared to other models, including commercial and conventional mathematical algorithms (Voxelmorph: 0.36 sec/images, Cyclemorph: 0.3 sec/images, Transmorph: 5.1 sec/images, SyN: 140 sec/images, NiftyReg: 40.2 sec/images). In conclusion, this study highlights the varying clinical applicability of deep learning-based DIR methods in different anatomical regions. While challenges were encountered in head and neck CT registrations, 4D lung CT registrations exhibited favorable results, indicating the potential for clinical implementation. Further research and development in DIR algorithms tailored to specific anatomical regions are warranted to improve the overall clinical utility of these methods.

Ultrasonographic evaluation of the masseter muscle in patients with temporomandibular joint degeneration

  • Busra Arikan;Numan Dedeoglu;Aydin Keskinruzgar
    • Imaging Science in Dentistry
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    • 제53권4호
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    • pp.355-363
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    • 2023
  • Purpose: Sonographic elastography can be used to evaluate the hardness of muscle tissue through the application of compression. Strain elastography gauges hardness through the comparison of echo sets before and after compression. This study utilized ultrasonography to measure the thickness and hardness of the masseter muscle in individuals with temporomandibular joint(TMJ) osteoarthritis. Materials and Methods: This study included 40 patients who presented with joint pain and were diagnosed with TMJ osteoarthritis via diagnostic cone-beam computed tomography, along with 40 healthy individuals. The thickness and hardness of each individual's masseter muscle were evaluated both at rest and at maximum bite using ultrasonography. The Mann-Whitney U test and the chi-square test were employed for statistical analysis, with the significance level set at P<0.05. Results: The mean thickness of the resting masseter muscle was 0.91 cm in patients with osteoarthritis, versus 1.00 cm in healthy individuals. The mean thickness of the masseter muscle at maximum bite was 1.28 cm in osteoarthritis patients and 1.36 cm in healthy individuals. The mean masseter elasticity index ratio at maximum bite was 4.51 in patients with osteoarthritis and 3.16 in healthy controls. Significant differences were observed between patients with osteoarthritis and healthy controls in both the masseter muscle thickness and the masseter elasticity index ratio, at rest and at maximum bite (P<0.05). Conclusion: The thickness of the masseter muscle in patients with TMJ osteoarthritis was less than that in healthy controls. Additionally, the hardness of the masseter muscle was greater in patients with TMJ osteoarthritis.

Digital Tomosynthesis versus Conventional Radiography for Evaluating Osteonecrosis of the Femoral Head

  • Yun Hwa Roh;Seunghun Lee;Jeong Ah Ryu;Yeo Ju Kim;Yeesuk Kim;Jiyoon Bae
    • Korean Journal of Radiology
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    • 제22권12호
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    • pp.2026-2033
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    • 2021
  • Objective: The aim of this study was to compare the diagnostic performances of digital tomosynthesis (DTS) and conventional radiography in detecting osteonecrosis of the femoral head (ONFH) using computed tomography (CT), as the reference standard and evaluate the diagnostic reproducibility of DTS. Materials and Methods: Forty-five patients (24 male and 21 female; age range, 25-77 years) with clinically suspected ONFH underwent anteroposterior radiography, DTS, and CT. Two musculoskeletal radiologists independently evaluated the presence and type of ONFH. The diagnostic performance of radiography and DTS in detecting the presence of ONFH and determining the types of ONFH were evaluated. The interobserver and intraobserver reliabilities of each imaging modality were analyzed using Cohen's kappa. Results: DTS had higher sensitivity (89.4%-100% vs. 74.5%-76.6%) and specificity (97.3%-100% vs. 78.4%-83.8%) for ONFH detection than radiography. DTS showed higher performance than radiography in identifying the subtypes of ONFH with statistical significance in one reader (type 1, 100% vs. 30.8%, p = 0.004; type II, 97.1% vs. 73.5%, p = 0.008). The interobserver agreement was excellent for DTS and moderate for radiography (kappa of 0.86 vs. 0.57, respectively). The intraobserver agreement for DTS was higher than that of radiography (kappa of 0.96 vs. 0.69, respectively). Conclusion: DTS showed higher diagnostic performance and reproducibility than radiography in detecting ONFH. DTS may be used as a first-line diagnostic modality instead of radiography for patients suspected of having ONFH.

Cervical spine reconstruction after total vertebrectomy using customized three-dimensional-printed implants in dogs

  • Ji-Won Jeon;Kyu-Won Kang;Woo-Keyoung Kim;Sook Yang;Byung-Jae Kang
    • Journal of Veterinary Science
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    • 제25권1호
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    • pp.2.1-2.14
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    • 2024
  • Background: Sufficient surgical resection is necessary for effective tumor control, but is usually limited for vertebral tumors, especially in the cervical spine in small animal neurosurgery. Objective: To evaluate the primary stability and safety of customized three-dimensional (3D)-printed implants for cervical spine reconstruction after total vertebrectomy. Methods: Customized guides and implants were designed based on computed tomography (CT) imaging of five beagle cadavers and were 3D-printed. They were used to reconstruct C5 after total vertebrectomy. Postoperative CT images were obtained to evaluate the safety and accuracy of screw positioning. After harvesting 10 vertebral specimens (C3-C7) from intact (group A) and implanted spines (group B), implant stability was analyzed using a 4-point bending test comparing with groups A and C (reconstituted with plate and pins/polymethylmethacrylate after testing in Group A). Results: All customized implants were applied without gross neurovascular damage. In addition, 90% of the screws were in a safe area, with 7.5% in grade 1 (< 1.3 mm) and 2.5% in grade 2 (> 1.3 mm). The mean entry point and angular deviations were 0.81 ± 0.43 mm and 6.50 ± 5.11°, respectively. Groups B and C significantly decreased the range of motion (ROM) in C3-C7 compared with intact spines (p = 0.033, and 0.018). Both groups reduced overall ROM and neutral zone in C4-C6, but only group B showed significance (p = 0.005, and 0.027). Conclusion: Customized 3D-printed implants could safely and accurately replace a cervical vertebra in dog cadavers while providing primary stability.

Early implant placement in sites with ridge preservation or spontaneous healing: histologic, profilometric, and CBCT analyses of an exploratory RCT

  • Stefan P. Bienz;Edwin Ruales-Carrera;Wan-Zhen Lee;Christoph H. F. Hammerle;Ronald E. Jung;Daniel S. Thoma
    • Journal of Periodontal and Implant Science
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    • 제54권2호
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    • pp.108-121
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    • 2024
  • Purpose: The aim of this study was to compare changes in soft and hard tissue and the histologic composition following early implant placement in sites with alveolar ridge preservation or spontaneous healing (SH), as well as implant performance up to 1 year after crown insertion. Methods: Thirty-five patients with either intact buccal bone plates or dehiscence of up to 50% following single-tooth extraction of incisors, canines, or premolars were included in the study. They were randomly assigned to undergo one of three procedures: deproteinized bovine bone mineral with 10% collagen (DBBM-C) covered by a collagen matrix (DBBM-C/CM), DBBM-C alone, or SH. At 8 weeks, implant placement was carried out, and cone-beam computed tomography scans and impressions were obtained for profilometric analysis. Patients were followed up after the final crown insertion and again at 1 year post-procedure. Results: Within the first 8 weeks following tooth extraction, the median height of the buccal soft tissue contour changed by -2.11 mm for the DBBM-C/CM group, -1.62 mm for the DBBM-C group, and -1.93 mm for the SH group. The corresponding height of the buccal mineralized tissue changed by -0.27 mm for the DBBM-C/CM group, -2.73 mm for the DBBM-C group, and -1.48 mm for the SH group. The median contour changes between crown insertion and 1 year were -0.19 mm in the DBBM-C/CM group, -0.09 mm in the DBBM-C group, and -0.29 mm in the SH group. Conclusions: Major vertical and horizontal ridge contour changes occurred, irrespective of the treatment modality, up to 8 weeks following tooth extraction. The DBBM-C/CM preserved more mineralized tissue throughout this period, despite a substantial reduction in the overall contour. All 3 protocols led to stable tissues for up to 1 year.

Minimally invasive percutaneous endoscopic thoracolumbar foraminotomy in large-breed dogs-a comparative study

  • Soo Hee Lee;Soo Young Choi;Ho Hyun Kwak;Heung Myong Woo
    • 한국동물위생학회지
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    • 제47권2호
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    • pp.61-72
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    • 2024
  • This study aimed to evaluate the feasibility of percutaneous endoscopic foraminotomy (PEF) for the treatment of intervertebral disc herniation of the thoracolumbar spine in large-breed dogs by comparing it with open hemilaminectomy (OH). Six large-breed canine cadavers were used in the present study. A barium and agarose mixture (BA-gel) simulating intervertebral disc herniation was injected into the spinal canal at two intervertebral spaces (T12-T13, L2-L3) of the thoracolumbar spine in each cadaver. PEF and OH were randomly allocated to the sites in each cadaver. Computed tomography was performed pre- and postoperatively. The incision length, vertebral window size, procedure time, and amount of simulated disc material removed were recorded to compare PEF and OH. Both procedures clearly exposed the simulated disc material and spinal cord. The size of the incision and vertebral window created after PEF was much smaller than those after OH. The surgical duration of PEF was longer than that of OH. However, no significant difference (P>0.05) was observed in the amount of BA-gel removed between PEF and OH. Thus, PEF could be used as an effective surgical option for intervertebral disc herniation of the thoracolumbar region in large-breed dogs in that it could lead to less tissue damage as well as sufficient removal of the simulated disc material.

기관지 내 염증성 근섬유모세포 종양: 증례 보고 (Inflammatory Endobronchial Myofibroblastic Tumor: A Case Report)

  • 남수원;정연주;이지원;이지원;엄중섭;조정수;박원영;박소민
    • 대한영상의학회지
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    • 제81권1호
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    • pp.219-224
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    • 2020
  • 염증성 근섬유모세포 종양은 전체 폐 종양의 0.04~1%를 차지하는 드문 양성 종양이며 대개 고립성 폐결절이나 종괴로 보인다. 우리는 21세 남자 환자에서의 기관지 내 염증성 근섬유모세포 종양 증례를 영상소견을 중심으로 보고하고 관련된 문헌을 고찰하고자 한다.

액와부 갈색지방종의 증례 보고: 초음파, 컴퓨터단층촬영, 자기공명영상, 병리 소견 (A Case Report of Axillary Hibernoma: US, CT, MR, and Histopathologic Findings)

  • 박지연;이성윤;이지영;권태정
    • 대한영상의학회지
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    • 제83권2호
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    • pp.439-443
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    • 2022
  • 갈색지방종은 갈색지방조직의 드문 양성 종양이다. 저자들은 53세 여자 환자에서 액와부 갈색지방종의 다양한 영상 소견을 보고하고자 한다. 초음파에서 오른쪽 액와부에 4.5 cm의 경계가 분명한 타원형의 비균질한 고에코의 종괴였으며, 액와부 혈관들을 앞쪽으로 전위시키고 있었다. 조영 전 흉부 단층촬영에서 5 cm의 경계가 분명한 타원형의 저감쇠의 종괴로 보였다. 자기공명영상에서는 T1과 T2 강조영상에서 비균질한 중간 및 고신호강도의 5.5 cm 종괴였으며, 변연부에서 불규칙한 조영증강을 보였다. 환자는 초음파유도중심부바늘생검을 받아 최종적으로 갈색지방종으로 진단되었다.

좌심방 부속기 동맥류: 증례 보고 (Left Atrial Appendage Aneurysm: A Case Report)

  • 최영재;김정숙;차윤기;한강민
    • 대한영상의학회지
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    • 제83권6호
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    • pp.1400-1405
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    • 2022
  • 좌심방 부속기 동맥류는 심장 빗살근의 선천성 이형성이나 승모판 또는 심근의 후천적 병변에 의해 생길 수 있는 매우 드문 심장 질환이다. 주로 흉부 CT나 심초음파에서 좌심방이 비정상적 팽창되어 우연히 발견되며, 환자의 대부분은 무증상이지만 생명을 위협하는 합병증과 관련이 있어 외과적 치료를 필요로 한다. 그러므로 정확한 진단과 함께 이에 동반된 합병증을 찾아내는 것은 중요하다. 본 증례 보고에서는 수술적 치료로 확진 된 53세 여성의 좌심방 부속기 동맥류를 소개하고 병태생리학을 바탕으로 진단과 함께 놓치지 말아야 할 합병증에 대한 CT 및 MRI 검사의 소견을 소개하고자 한다.