• Title/Summary/Keyword: 3D Volumes

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Dosimetric Comparison between Intensity Modulated Radiotherapy and 3 Dimensional Conformal Radiotherapy in the Treatment of Rectal Cancer

  • Simson, David K;Mitra, Swarupa;Ahlawat, Parveen;Sharma, Manoj Kumar;Yadav, Girigesh;Mishra, Manindra Bhushan
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.11
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    • pp.4935-4937
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    • 2016
  • Objective: To compare dosimetric parameters of 3 dimensional conformal radiotherapy (3 DCRT) and intensity modulated radiotherapy (IMRT) in terms of target coverage and doses to organs at risk (OAR) in the management of rectal carcinoma. Methods: In this prospective study, conducted between August 2014 and March 2016, all patients underwent CT simulation along with a bladder protocol and target contouring according to the Radiation Therapy Oncology Group (RTOG) guidelines. Two plans were made for each patient (3 DCRT and IMRT) for comparison of target coverage and OAR. Result: A total of 43 patients were recruited into this study. While there were no significant differences in mean Planning Target Volume (PTV) D95% and mean PTV D98% between 3 DCRT and IMRT, mean PTV D2% and mean PTV D50% were significantly higher in 3 DCRT plans. Compared to IMRT, 3 DCRT resulted in significantly higher volumes of hot spots, lower volumes of cold spots, and higher doses to the entire OAR. Conclusion: This study demonstrated that IMRT achieves superior normal tissue avoidance (bladder and bowel) compared to 3 DCRT, with comparable target dose coverage.

Three-dimensional Capsular Volume Measurements in Multidirectional Shoulder Instability

  • Jun, Yong Cheol;Moon, Young Lae;Elsayed, Moustafa I.;Lim, Jae Hwan;Cha, Dong Hyuk
    • Clinics in Shoulder and Elbow
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    • v.21 no.3
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    • pp.134-137
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    • 2018
  • Background: In a previous study undertaken to quantify capsular volume in rotator cuff interval or axillary pouch, significant differences were found between controls and patients with instability. However, the results obtained were derived from two-dimensional cross sectional areas. In our study, we sought correlation between three-dimensional (3D) capsular volumes, as measured by magnetic resonance arthrography (MRA), and multidirectional instability (MDI) of the shoulder. Methods: The MRAs of 21 patients with MDI of the shoulder and 16 control cases with no instability were retrospectively reviewed. Capsular areas determined by MRA were translated into 3D volumes using 3D software Mimics ver. 16 (Materilise, Leuven, Belgium), and glenoid surface area was measured in axial and coronal MRA views. Then, the ratio between capsular volume and glenoid surface area was calculated, and evaluated with control group. Results: The ratio between 3D capsular volume and glenoid surface area was significantly increased in the MDI group ($3.59{\pm}0.83cm^3/cm^2$) compared to the control group ($2.53{\pm}0.62cm^3/cm^2$) (p<0.01). Conclusions: From these results, we could support that capsular volume enlargement play an important role in MDI of the shoulder using volume measurement.

The Effect of Volume Reduction on Computed Treatment Planning during Head and Neck IMRT and VMAT (두경부 IMRT 및 VMAT 시 체적 감소가 전산화치료계획에 미치는 영향)

  • Ki-Cheon Um;Gha-Jung Kim;Geum-Mun Back
    • Journal of radiological science and technology
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    • v.46 no.3
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    • pp.239-246
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    • 2023
  • In this study, we assessed the effect of reduction of tumor volume in the head and neck cancer by using RANDO phantom in Static Intensity-Modulated Radiation Therapy (S-IMRT) and Volumetric-Modulated Arc Therapy (VMAT) planning. RANDO phantom's body and protruding volumes were delineated by using Contour menu of Eclipse™ (Varian Medical System, Inc., Version 15.6, USA) treatment planning system. Inner margins of 2 mm to 10 mm from protruding volumes of the reference were applied to generate the parameters of reduced volume. In addition, target volume and Organ at Risk (OAR) volumes were delineated. S-IMRT plan and VMAT plan were designed in reference. These plans were assigned in the reduced volumes and dose was calculated in reduced volumes using preset Monitor unit (MU). Dose Volume Histogram (DVH) was generated to evaluate treatment planning. Conformity Index (CI) and R2 in reference S-IMRT were 0.983 and 0.015, respectively. There was no significant relationship between CI and the reduced volume. Homogeneity Index (HI) and R2 were 0.092 and 0.960, respectively. The HI increased when volume reduced. In reference VMAT, CI and R2 were 0.992 and 0.259, respectively. There was no relationship between the volume reduction and CI. On the other hand, HI and R2 were 0.078 and 0.895, respectively. The value of HI increased when the volume reduced. There was significant difference (p<0.05) between parameters (Dmean and Dmax) of normal organs of S-IMRT and VMAT except brain stem. Volume reduction affected the CI, HI and OAR dose. In the future, additional studies are necessary to incorporate the reduction of the volume in the clinical setting.

MARS/MASTER Solution to OECD Main Steam Line Break Benchmark Exercise III

  • Jeong, Jae-Jun;Joo, Han-Gyu;Chung, Bub-Dong;Ha, Kwi-Seok;Lee, Won-Jae;Cho, Byung-Oh;Zee, Sung-Quun
    • Nuclear Engineering and Technology
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    • v.32 no.3
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    • pp.214-226
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    • 2000
  • In an effort to assess the performance of KAERI's coupled 3D kinetics - system T/H code, MARS/MASTER, Exercise III of the OECD main steam line break benchmark is solved. The analysis model of the reference plant, TMI-1 - a 2772 MWth B&W plant, consists of three major components: a core neutronics model involving 241$\times$28 neutronic nodes, a vessel 3D T/H model consisting of 374 hydrodynamic volumes, and a 1D system T/H model containing 157 hydrodynamic volumes. The results show that there is a significant amount of flow mixing occurring in the upper and lower plenum regions and the core power distribution evolves to a highly localized shape due to the presence of a stuck rod, as well as the asymmetric flow distribution. It is judged that MARS/MASTER properly captures these drastic 3-dimensional effects. Comparisons with other results submitted to OECD confirm the accuracy of the MARS/MASTER solution.

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Comparison of the three-dimensional structures of mandibular condyles between adults with and without facial asymmetry: A retrospective study

  • Oh, Min-Hee;Kang, Sung-Ja;Cho, Jin-Hyoung
    • The korean journal of orthodontics
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    • v.48 no.2
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    • pp.73-80
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    • 2018
  • Objective: This retrospective study compared the three-dimensional (3D) structure of mandibular condyles between adults with and without facial asymmetry, and whether it influences menton deviation. Methods: Sixty adult patients were classified into symmetry and asymmetry groups based on the menton deviation on postero-anterior radiographs. The right/left differences of 3D measurements were compared between the two groups, and measurements were compared separately on the right and left sides. The correlations between menton deviation and the right/left differences were analyzed. Results: The mediolateral dimension, neck length, condylar angles to the anteroposterior reference (PO) and midsagittal reference planes, and neck and head volumes showed significantly larger right/left differences in the asymmetry group compared to the symmetry group. Separate comparisons of the right and left sides between the two groups showed that the neck was significantly shorter and neck and head volumes were significantly smaller on the left side, which was deviated side in the asymmetry group. Pearson's correlation analysis showed significant positive correlations of menton deviation with right/left differences in neck length, condylar angle to the PO plane, and neck and head volumes in the asymmetry group. Conclusions: In individuals with facial asymmetry, menton deviation is associated with the right/left differences caused by a smaller condyle on the deviated side, particularly in neck length and neck and head volumes.

Comparison of mastoid air cell volume in patients with or without a pneumatized articular tubercle

  • Adisen, Mehmet Zahit;Aydogdu, Merve
    • Imaging Science in Dentistry
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    • v.52 no.1
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    • pp.27-32
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    • 2022
  • Purpose: The aim of this study was to compare mastoid air cell volumes in patients with or without a pneumatized articular tubercle (PAT) on cone-beam computed tomography (CBCT) images. Materials and Methods: The CBCT images of 224 patients were retrospectively analyzed for the presence of PAT. The Digital Imaging and Communications in Medicine data of 30 patients with PAT and 30 individuals without PAT were transferred to 3D Doctor Software. Mastoid air cell volumes were measured using semi-automatic segmentation on axial sections. Data were analyzed using SPSS version 20.0. Results: The patients with PAT and those without PAT had a mean mastoid volume of 6.31±2.86 cm3 and 3.25±1.99 cm3, respectively. There were statistically significant differences in mastoid air cell volumes between patients with and without PAT regardless of sex and mastoid air cell side (P<0.05). Conclusion: The detection of PAT on routine dental radiographic examinations might be a potential prognostic factor that could be used to detect extensive pneumatization in the temporal bone. Clinicians should be aware that there may be widespread pneumatization of mastoid air cells in patients in whom PAT is detected. Advanced imaging should be performed in these cases, and possible complications due to surgical interventions should be considered.

Automatic Lung Registration using Local Distance Propagation (지역적 거리전파를 이용한 자동 폐 정합)

  • Lee Jeongjin;Hong Helen;Shin Yeong Gil
    • Journal of KIISE:Software and Applications
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    • v.32 no.1
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    • pp.41-49
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    • 2005
  • In this Paper, we Propose an automatic lung registration technique using local distance propagation for correcting the difference between two temporal images by a patient's movement in abdomen CT image obtained from the same patient to be taken at different time. The proposed method is composed of three steps. First, lung boundaries of two temporal volumes are extracted, and optimal bounding volumes including a lung are initially registered. Second, 3D distance map is generated from lung boundaries in the initially taken volume data by local distance propagation. Third, two images are registered where the distance between two surfaces is minimized by selective distance measure. In the experiment, we evaluate a speed and robustness using three patients' data by comparing chamfer-matching registration. Our proposed method shows that two volumes can be registered at optimal location rapidly. and robustly using selective distance measure on locally propagated 3D distance map.

Advances in Imaging of Subsurface Archaeology using GPR

  • Dean, Goodman;Yasushi, Nishimur;Kent, Schneider;Salvadore, Piro;Hiromichi, Hongo;Noriaki, Higashi
    • Journal of the Korean Geophysical Society
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    • v.7 no.3
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    • pp.161-170
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    • 2004
  • Examples of GPR survey results at a variety of archaeological sites are presented. Several new analyses which include static corrections for the tilt of the GPR antenna are shown for imaging of burial mounds with significant topography. Example archaeological site plans developed from GPR remote sensing of Roman and Japanese sites are given. The first completely automated GPR survey, using only Global Positioning Satellite navigation to create 3D data volumes, is employed for a site in Louisiana to detect lost graves of the Choctaw Indian Tribe.

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Bladder Volume Variations in Patients Receiving Conformal Radiotherapy to Prostate (전립선암 환자의 방사선 치료 시 방광 체적 변화)

  • Lee, Re-Na;Lee, Ji-Hye;Lee, Kyung-Ja;Ji, Young-Hoon
    • Journal of Radiation Protection and Research
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    • v.33 no.2
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    • pp.61-65
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    • 2008
  • Objective: To reduce urinary side effects in prostate cancer patients receiving radiation, patients were asked to drink certain amount of water to maintain bladder volume constant and the bladder volumes were measured weekly using ultrasound scanner. Materials and Methods: Twenty-six patients with prostate cancer who received radiation between December 2002 and August 2007 were enrolled in this study. Thirteen patients were enrolled in experimental group. These patients were asked to drink 450 cc of water, one hour prior to simulation, CT scan, and treatment. The other thirteen patients were given no information about bladder filing. Bladder, prostate, and rectum were contoured on CT and volumes were calculated. 3D conformal treatment planning was performed and effective volumes of bladder were calculated when a prescription dose of 70.2 Gy was delivered. For the patients in experimental group, bladder volumes were measured weekly using ultrasound scanner for 6-8 weeks and the bladder volume variations were analyzed. Results: Average bladder volumes and standard deviations obtained at CT scanning were $283.5{\pm}114.0\;cc$ (40%) and $181.2{\pm}120.1\;cc$ (66%) in experimental and control groups, respectively. Although it was not statistically significant, there was correlation between the bladder volumes measured from CT and ultrasound. The volumes measured using ultrasound scanner were 62% lower than the volumes using CT images on average. There was significant variations in volumes measured weekly for 6-8 weeks. It ranged between 33 - 75 %. Conclusion: Our results showed that it is possible to obtain larger bladder volume if they are asked to drink certain amount of water prior to CT scan. However, patients were unable to maintain constant bladder volumes over the 6-8 weeks of treatment period although they were asked to drink constant amount of water.

Design and Implementation of Multi-View 3D Video Player (다시점 3차원 비디오 재생 시스템 설계 및 구현)

  • Heo, Young-Su;Park, Gwang-Hoon
    • Journal of Broadcast Engineering
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    • v.16 no.2
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    • pp.258-273
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    • 2011
  • This paper designs and implements a multi-view 3D video player system which is operated faster than existing video player systems. The structure for obtaining the near optimum speed in a multi-processor environment by parallelizing the component modules is proposed to process large volumes of multi-view image data at high speed. In order to use the concurrency of bottleneck, we designed image decoding, synthesis and rendering modules in a pipeline structure. For load balancing, the decoder module is divided into the unit of viewpoint, and the image synthesis module is geometrically divided based on synthesized images. As a result of this experiment, multi-view images were correctly synthesized and the 3D sense could be felt when watching the images on the multi-view autostereoscopic display. The proposed application processing structure could be used to process large volumes of multi-view image data at high speed, using the multi-processors to their maximum capacity.