• Title/Summary/Keyword: Three-dimensional computed tomography

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Evaluation of the heart and lung dosimetric parameters in deep inspiration breath hold using 3D Slicer

  • Eskandari, Azam;Nasseri, Shahrokh;Gholamhosseinian, Hamid;Hosseini, Sare;Farzaneh, Mohammad Javad Keikhai;Keramati, Alireza;Naji, Maryam;Rostami, Atefeh;Momennezhad, Mehdi
    • Radiation Oncology Journal
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    • v.38 no.1
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    • pp.68-76
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    • 2020
  • Purpose: The present study was conducted to compare dosimetric parameters for the heart and left lung between free breathing (FB) and deep inspiration breath hold (DIBH) and determine the most important potential factors associated with increasing the lung dose for left-sided breast radiotherapy using image analysis with 3D Slicer software. Materials and Methods: Computed tomography-simulation scans in FB and DIBH were obtained from 17 patients with left-sided breast cancer. After contouring, three-dimensional conformal plans were generated for them. The prescribed dose was 50 Gy to the clinical target volume. In addition to the dosimetric parameters, the irradiated volumes and both displacement magnitudes and vectors for the heart and left lung were assessed using 3D Slicer software. Results: The average of the heart mean dose (Dmean) decreased from 5.97 to 3.83 Gy and V25 from 7.60% to 3.29% using DIBH (p < 0.001). Furthermore, the average of Dmean for the left lung was changed from 8.67 to 8.95 Gy (p = 0.389) and V20 from 14.84% to 15.44% (p = 0.387). Both of the absolute and relative irradiated heart volumes decreased from 42.12 to 15.82 mL and 8.16% to 3.17%, respectively (p < 0.001); however, these parameters for the left lung increased from 124.32 to 223.27 mL (p < 0.001) and 13.33% to 13.99% (p = 0.350). In addition, the average of heart and left lung displacement magnitudes were calculated at 7.32 and 20.91 mm, respectively. Conclusion: The DIBH is an effective technique in the reduction of the heart dose for tangentially treated left sided-breast cancer patients, without a detrimental effect on the left lung.

A Study on the Estimation of Calcaneal Width Using a Correlation of Calcaneal Length and Width (종골 길이와 너비의 상관관계를 이용한 종골 너비 추정에 관한 연구)

  • Chun, Dong-il;Hwang, Shu Chiang;Cho, Jae-ho;Choi, Sung-Woo;Kim, Yong Beom;Won, Sung Hun
    • Journal of Korean Foot and Ankle Society
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    • v.21 no.2
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    • pp.61-65
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    • 2017
  • Purpose: The purpose of this study was to determine the correlation and ratio between the calcaneal length and width for predicting the width of calcaneus. Materials and Methods: A total of 190 feet (190 patients) were included based on computed tomography scans. The length of calcaneus (CL) was measured on the line connecting the center of a circle tangent to the cortical margin in the anterior and posterior parts of the calcaneus in a sagittal plane (W1, W2). The width of the calcaneus was defined as the horizontal line of each part (W1, W2, W3) on the same axial plane. The relationship between the measurement was determined through a correlation analysis. The reliability was assessed based on intraclass correlation coefficients. Results: The CL and widths of calcaneus (W1, W2, W3) had a good positive correlation (r=0.848 [W1/CL], r=0.738 [W2/CL], r=0.769 [W3/CL]; p<0.001). The mean CL and widths ratios were 0.33 (W1/CL), 0.37 (W2/CL), and 0.37 (W3/CL). Using these ratios to estimate the widths by multiplying each ratio by the measured calcaneal length, we found a difference between the estimated calcaneal widths and the actual measured calcaneal widths values was 0.25 mm, 0.43 mm, and 0.16 mm. All measurements showed good-to-excellent inter- and intraobserver reliability. Conclusion: This study analyzed the correlation and ratio between the length and width of the calcaneus. The results will help orthopedic surgeons fixate screws in a stable manner to prevent iatrogenic injuries to the medial neurovascular structures of the calcaneus.

THE SINGLE PHOTON EMISSION COMPUTED TOMOGRAPHY FINDINGS IN DEVELOPMENTAL LANGUAGE DISORDERS (발달성언어장애아(發達性言語障碍兒)의 단일광자방출전산화단층촬영(單一光子防出電算化斷層撮影) 소견(所見)에 관한 연구)

  • Park, Jin-Seng;Cho, Soo-Churl;Lee, Myung-Chul
    • Journal of the Korean Academy of Child and Adolescent Psychiatry
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    • v.3 no.1
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    • pp.46-55
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    • 1992
  • The pathophysiology of developmental language disorder is a highly controversial matter. In order to investigate the neural mechanisms involved in developmental language disorders, the authors studied three dimensional regional cerebral blood flow(rCBF) using Tc-99mH-MPAO in 42 children with developmental language disorders. The results are summarized as follows : 1) 61.9% (26/42) of this series revealed decreased perfusion in SPECT. 2) Regions of hypoperfusion were seen in cerebral cortex(47.6%, 20/42), thalamus(33.3%, 14/42), basal ganglia(11.9%, 5/42) and cerebellum(7.1%, 3/42). This study suggests that developmental language disorder could be due to specific functional impairment of the local brain regions which could not detected by conventional investigations such as brain CT or EEG.

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The Change of Facial Contouring after Unilateral Injection of Botulinum Toxin in Unilateral Masseter Hypertrophy Patients (편측성 교근비대 환자에서 편측 보툴리눔 독소 주사 후 안모의 변화)

  • Cha, Yu-Rim;Kim, Young-Gun;Kim, Ji-Hyun;Shim, Young-Joo;Kim, Seong-Taek
    • Journal of Dental Rehabilitation and Applied Science
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    • v.27 no.2
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    • pp.247-251
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    • 2011
  • Botulinum toxin type A (BoNT-A) is used for treating bilateral masseter hypertrophy since 1994. Recently there have been more clinical studies in this area, with some authors reporting that BoNT-A can reduce the size of the masseter muscle, as documented by photography, ultrasonography, computed tomography, and 3D(three dimensional) laser scan. However, earlier studies were only for bilateral masseter hypertrophy cases, not for unilateral masseter hypertrophy cases. The aim of this study was to use 3D laser scanning to evaluate changes in the external facial contour induced by unilateral BoNT-A injection. BoNT-A was injected into hypertrophic masseter muscle unilaterally in 10 patients with asymmetric masseter hypertrophy. The clinical effects of unilaterally injected BoNT-A were evaluated before the injection and 4, 8, and 12weeks after the injection using 3D laser scan. And the mean values of both sides (injection and non-injection sides) were compared with. At injection side, mean values of the volume and the bulkiest height at each time point diminished significantly between pre-injection and 4, 8, and 12weeks post-injection. At non-injection side, in contrast, mean values of the volume and the bulkiest height diminished also but less than that of injected side, and there was no statistical significance. In this limited study, we concluded that the unilaterally BoNT-A injection side showed greater mean values of the reduction of muscle volume than non-injection side at 4, 8, and 12 weeks after the injection.

Positional changes of the mandibular condyle in unilateral sagittal split ramus osteotomy combined with intraoral vertical ramus osteotomy for asymmetric class III malocclusion

  • Park, Jun;Hong, Ki-Eun;Yun, Ji-Eon;Shin, Eun-Sup;Kim, Chul-Hoon;Kim, Bok-Joo;Kim, Jung-Han
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.47 no.5
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    • pp.373-381
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    • 2021
  • Objectives: In the present study, the effects of sagittal split ramus osteotomy (SSRO) combined with intraoral vertical ramus osteotomy (IVRO) for the treatment of asymmetric mandible in class III malocclusion patients were assessed and the postoperative stability of the mandibular condyle and the symptoms of temporomandibular joint disorder (TMD) evaluated. Materials and Methods: A total of 82 patients who underwent orthognathic surgery for the treatment of facial asymmetry or mandibular asymmetry at the Department of Oral and Maxillofacial Surgery, Dong-A University Hospital, from 2016 to 2021 were selected. The patients that underwent SSRO with IVRO were assigned to Group I (n=8) and patients that received bilateral SSRO (BSSRO) to Group II (n=10, simple random sampling). Preoperative and postoperative three-dimensional computed tomography (CT) axial images obtained for each group were superimposed. The condylar position changes and degree of rotation on the superimposed images were measured, and the changes in condyle based on the amount of chin movement for each surgical method were statistically analyzed. Results: Group I showed a greater amount of postoperative chin movement. For the amount of mediolateral condylar displacement on the deviated side, Groups I and II showed an average lateral displacement of 0.07 mm and 1.62 mm, respectively, and statistically significantly correlated with the amount of chin movement (P=0.004). Most of the TMD symptoms in Group I patients who underwent SSRO with IVRO showed improvement. Conclusion: When a large amount of mandibular rotation is required to match the menton to the midline of the face, IVRO on the deviated side is considered a technique to prevent condylar torque. In the present study, worsening of TMD symptoms did not occur after orthognathic surgery in any of the 18 patients.

MDCT Angiography of the Subclavian Artery Thrombosis of the 3D Findings (쇄골하동맥 혈전증에서의 MDCT 혈관조영술의 3D 영상)

  • Kweon, Dae Cheol
    • Journal of the Korean Society of Radiology
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    • v.12 no.7
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    • pp.813-819
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    • 2018
  • To demonstrate the 3D usefulness of MDCT, a 73-year-old male patient with subclavian thrombosis was obtained 3D images of maximum intensity projection (MIP), volume rendering, and multiplanar reformation (MPR) to clearly detect and locate the subclavian artery. The data will be provided to the patient for diagnosis and treatment. The scan data were acquired as 3D CT images MIP, volume rendering, curved MPR, and virtual endoscopy images. In the 3D program, the ascending aorta was measured as 364.28 HU, the left carotid artery was 413.77 HU, and the left subclavian artery was 15.72 HU. MIP coronal image shows the closure of the subclavian artery in the left side. Three-dimensional volume images were obtained with 100% permeability and 87-1265 HU. The coronal curved MPR and sagittal curved MPR images show the closure of the subclavian artery due to thrombus using 3D image processing. In the case of subclavian arterial occlusion due to thrombosis, the patient is scanned with MDCT and 3D image processing can be used to confirm occlusion of subclavian artery.

Usage of digital technique to facilitate communication between dentist, dental lab technician, and patients in diagnosis and restoration for maxillary anterior implant: a case report (디지털 기법을 활용한 치과의사, 기공사, 그리고 환자 간의 효과적인 소통을 통한 전치부 임플란트의 진단 및 심미수복 증례)

  • Bang, Haemin;Jang, Woohyung;Park, Chan;Yun, Kwi-Dug;Lim, Hyun-Pil;Park, Sangwon
    • Journal of Dental Rehabilitation and Applied Science
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    • v.38 no.1
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    • pp.42-51
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    • 2022
  • Esthetic restoration of maxillary anterior implant heavily depends on the direction of installation of implant fixture. In patients with malpositioned implant, it is crucial to communicate the limitations of prosthetic outcome with the patient before starting on a restoration. To facilitate the communication, three-dimensional virtual representation by superimposing facial and intraoral digital scans with Computed Tomography (CT, dicom file) was used for visualization of the limitations of prosthesis. Through digital diagnostic wax-up, the profile of right maxillary anterior incisor implant was expected to be protrusive, which the patient was not satisfied with. Since the patient already had done root canal treatment on left maxillary anterior incisor due to previous trauma, a new prosthetic design including both right and left maxillary anterior incisors was presented to the patient. The second design was chosen and his comments were delivered to dental lab. The patient was satisfied with the new prosthesis, aesthetically and functionally.

Visualization and Localization of Fusion Image Using VRML for Three-dimensional Modeling of Epileptic Seizure Focus (VRML을 이용한 융합 영상에서 간질환자 발작 진원지의 3차원적 가시화와 위치 측정 구현)

  • 이상호;김동현;유선국;정해조;윤미진;손혜경;강원석;이종두;김희중
    • Progress in Medical Physics
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    • v.14 no.1
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    • pp.34-42
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    • 2003
  • In medical imaging, three-dimensional (3D) display using Virtual Reality Modeling Language (VRML) as a portable file format can give intuitive information more efficiently on the World Wide Web (WWW). The web-based 3D visualization of functional images combined with anatomical images has not studied much in systematic ways. The goal of this study was to achieve a simultaneous observation of 3D anatomic and functional models with planar images on the WWW, providing their locational information in 3D space with a measuring implement using VRML. MRI and ictal-interictal SPECT images were obtained from one epileptic patient. Subtraction ictal SPECT co-registered to MRI (SISCOM) was performed to improve identification of a seizure focus. SISCOM image volumes were held by thresholds above one standard deviation (1-SD) and two standard deviations (2-SD). SISCOM foci and boundaries of gray matter, white matter, and cerebrospinal fluid (CSF) in the MRI volume were segmented and rendered to VRML polygonal surfaces by marching cube algorithm. Line profiles of x and y-axis that represent real lengths on an image were acquired and their maximum lengths were the same as 211.67 mm. The real size vs. the rendered VRML surface size was approximately the ratio of 1 to 605.9. A VRML measuring tool was made and merged with previous VRML surfaces. User interface tools were embedded with Java Script routines to display MRI planar images as cross sections of 3D surface models and to set transparencies of 3D surface models. When transparencies of 3D surface models were properly controlled, a fused display of the brain geometry with 3D distributions of focal activated regions provided intuitively spatial correlations among three 3D surface models. The epileptic seizure focus was in the right temporal lobe of the brain. The real position of the seizure focus could be verified by the VRML measuring tool and the anatomy corresponding to the seizure focus could be confirmed by MRI planar images crossing 3D surface models. The VRML application developed in this study may have several advantages. Firstly, 3D fused display and control of anatomic and functional image were achieved on the m. Secondly, the vector analysis of a 3D surface model was defined by the VRML measuring tool based on the real size. Finally, the anatomy corresponding to the seizure focus was intuitively detected by correlations with MRI images. Our web based visualization of 3-D fusion image and its localization will be a help to online research and education in diagnostic radiology, therapeutic radiology, and surgery applications.

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Three Dimensional Measurements of Pore Morphological and Hydraulic Properties (토양 공극 형태와 수문학적 특성에 대한 3 차원적 측정)

  • Chun, Hyen-Chung;Gimenez, Daniel;Yoon, Sung-Won;Heck, Richard;Elliot, Tom;Ziska, Laise;Geaorge, Kate;Sonn, Yeon-Kyu;Ha, Sang-Keun
    • Korean Journal of Soil Science and Fertilizer
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    • v.43 no.4
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    • pp.415-423
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    • 2010
  • Pore network models are useful tools to investigate soil pore geometry. These models provide quantitative information of pore geometry from 3D images. This study presents a pore network model to quantify pore structure and hydraulic characteristics. The objectives of this work were to apply the pore network model to characterize pore structure from large images to quantify pore structure, calculate water retention and hydraulic conductivity properties from a three dimensional soil image, and to combine measured hydraulic properties from experiments with calculated hydraulic properties from image. Soil samples were taken from a site located at the Baltimore science center, which is located inside of the city. Undisturbed columns were taken from the site and scanned with a computer tomographer at resolutions of 22 ${\mu}m$. Pore networks were extracted by medial-axis transformation and were used to measure pore geometry from one of the scanned samples. Water retention and unsaturated hydraulic conductivity values were calculated from the soil image. Properties of soil bulk density, water retention and unsaturated hydraulic conductivity were measured from three replicates of scanned soil samples. 3D image analysis provided accurate detailed pore properties such as individual pore volumes, pore length, and tortuosity of all pores. These data made possible to calculate accurate estimations of water retention and hydraulic conductivity. Combination of the calculated and measured hydraulic properties gave more accurate information on pore sizes over wider range than measured or calculated data alone. We could conclude that the hydraulic property computed from soil images and laboratory measurements can describe a full structure of intra- and inter-aggregate pores in soil.

Changes of lip morphology following mandibular setback surgery using 3D cone-beam computed tomography images

  • Paek, Seung Jae;Yoo, Ji Yong;Lee, Jang Won;Park, Won-Jong;Chee, Young Deok;Choi, Moon Gi;Choi, Eun Joo;Kwon, Kyung-Hwan
    • Maxillofacial Plastic and Reconstructive Surgery
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    • v.38
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    • pp.38.1-38.10
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    • 2016
  • Background: The aims of this study are to evaluate the lip morphology and change of lip commissure after mandibular setback surgery (MSS) for class III patients and analyze association between the amount of mandibular setback and change of lip morphology. Methods: The samples consisted of 14 class III patients treated with MSS using bilateral sagittal split ramus osteotomy. Lateral cephalogram and cone-beam CT were taken before and about 6 months after MSS. Changes in landmarks and variables were measured with 3D software program $Ondemand^{TM}$. Paired and independent t tests were performed for statistical analysis. Results: Landmarks in the mouth corner (cheilion, Ch) moved backward and downward (p < .005, p < .01). However, cheilion width was not statistically significantly changed. Landmark in labrale superius (Ls) was not altered significantly. Upper lip prominence angle (ChRt-Ls-$ChLt^{\circ}$) became acute. Landmarks in stomion (Stm), labrale inferius (Li) moved backward (p < .005, p < .001). Lower lip prominence angle (ChRt-Li-$ChLt^{\circ}$) became obtuse (p < .001). Height of the upper and lower lips was not altered significantly. Length of the upper lip vermilion was increased (p =< 0.01), and length of the lower lip vermilion was decreased (p < .05). Lip area on frontal view was not statistically significantly changed, but the upper lip area on lateral view was increased and change of the lower lip area decreased (p > .05, p < .005). On lateral view, upper lip prominent point (UP) moved downward and stomion moved backward and upward and the angle of Ls-UP-Stm ($^{\circ}$) was decreased. Lower lip prominent point (LP) moved backward and downward, and the angle of Stm-LP-Li ($^{\circ}$) was increased. Li moved backward. Finally, landmarks in the lower incisor tip (L1) moved backward and upward, but stomion moved downward. After surgery, lower incisor tip (L1) was positioned more superiorly than stomion (p < .05). There were significant associations between horizontal soft tissue and corresponding hard tissue. The posterior movement of L1 was related to statistically significantly about backward and downward movement of cheilion. Conclusions: The lip morphology of patients with dento-skeletal class III malocclusion shows a significant improvement after orthognathic surgery. Three-dimensional lip morphology changes in class III patients after MSS exhibited that cheilion moved backward and downward, upper lip projection angle became acute, lower lip projection angle became obtuse, change of upper lip area on lateral view was increased, change of lower lip area decreased, and morphology of lower lip was protruding. L1 was concerned with the lip tissue change in statistically significant way.