• Title/Summary/Keyword: Head tilting

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Evaluation of Treatment Planning for Head Tilting in WBRT 3D-CRT by TomoDirect mode: a Phantom Study (토모다이렉트를 이용한 3차원 전뇌 방사선치료에서 두상 각도에 따른 치료계획평가: 팬톰 실험)

  • Dae-Gun, Kim;Sang-Hyun, Kim
    • Journal of the Korean Society of Radiology
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    • v.16 no.7
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    • pp.857-862
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    • 2022
  • The purpose of this study was to evaluate a three-dimensional conformal radiotherapy (3D-CRT) treatment plan with regard to head tilting in whole-brain radiotherapy (WBRT) using TomoDirect (TD) mode in Tomotherapy. WBRT 3D-CRT by TD was compared for a total of five head tilt angles (-20°, -10°, 0°. +10° and +20°). The dose homogeneity index (HI) and prescription dose index (CI) were calculated to confirm the target coverage. The maximum and average doses for critical organs such as the lens, eyeball and parotid glands were calculated for different angles of head tilting. The HI and CI were closet to the result value of 1 at the head tilted angle +10° and +20°. At a head tilted angle of +10°, the dose to the lens and eyeballs decreased by about 74% and about 30%, when compared with the reference angle (0°), respectively. The results of this study suggest that a head angle of +10 with chin-up would save adequate target coverage and reduce exposure dose to the lens.

Ananlysis of Correlation between Functional Leg Length Discrepancy caused by Pelvic tilting and Femur head height difference (골반변위와 대퇴골두 높이차이에 대한 상관성 비교 - Gonstead's Technique을 중심으로 -)

  • Lee, Kyung-Yun;Seo, Jin-Woo;Park, Kwae-Hwan;Park, Min-Jung
    • The Journal of Korea CHUNA Manual Medicine
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    • v.5 no.1
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    • pp.213-222
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    • 2004
  • Objectives : To investigate contributing degree of other factors except pelvic tilting to F.L.L.D by analizing with Gonstead technique on the correlation between femur head height discrepancy on the standing pelvic AP view and F.L.L.D caused by pelvic tilting. Method : We analysed standing pelvis AP X-ray of 70 patients who had visited at the department acupunture and moxibustion in Conmaul oriental medical hospital, during May, 1st, 2004 - July, 30th, 2004, with low back pain or lower extremity pain. We excluded the person with any past history of polio, genetic defect, malunited fracture, growth plate injury, infection and overgrowth attributable to hemangioma, or arteriovenous fistula. Results & Conclusion : The functional leg length discrepancy caused by pelvic tilting and femur head height difference had no statistical difference(p=0.132) but poorly correlated(Pearson ${\nu}=0.05$). In the 94.28% of subjects, the femur head height difference wasn't in accord with F.L.L.D. caused by pelvic tilting. In 47.14% of subjects were expected to have over $3^{mm}$ of leg length discrepancy after pelvic adjustment. The mean of measurement difference between two methods was $3.76{\pm}3.12^{mm}$ and the range was $0{\sim}11.4^{mm}$. Consequently, we must consider not only functional leg length discrepancy caused by pelvic tilting but also anatomical leg length discrepancy, misalignment of ankle, knee or hip joint etc.

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A Study of Circulatory Responses to Postural Changes (체위변화에 수반되는 심맥관계반응에 관한연구)

  • Suh, Suk-Wan;Chae, E-Up
    • The Korean Journal of Physiology
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    • v.5 no.2
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    • pp.71-78
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    • 1971
  • Anesthetized dogs were tilted from horizontal to the upright and head down position. Tilting to the upright position was followed by an increase in heart rate. In the head down position a decreased heart rate was obtained. The arterial blood pressure was decreased in the upright position and was decreased markedly in the head down position. The central venous pressure was decreased in the upright position and was markedly decreased down to the negative pressure in the head down position. The respiratory rate was slightly increased in the upright position comparing to that in the horizontal position. No remarkable changes were noted in the head down position. From the above results the following factors were discussed The decreased arterial blood pressure during the upright position was supposed to be the secondary effect from the diminished venous return that was suggested by the decreased central venous pressure. The decreased arterial blood pressure in the head down position was also supposed as the above reason as the diminished central venous pressure during the tilt. In addition the cardioinhibitory effects originated from the baroreceptors might have been operated during head down tilting. In the heart rate there was slight tachycardia in the upright position this was assumed as the abolished cardioinhibitory impulses from the baroreceptor in the upright position. On the contrary, despite of the decrease of arterial blood pressure in the head down position as well as in the upright, the bradycardia have been appeared. This was suggestive of cardioinhibitory impulses from the baroreceptors which was stretched during head down tilting. From the above findings there is a possibility of continous cardioinhibitory responses during head down tilting for this kind of the short period of 10 minutes which was chosed in this study.

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The Effect of Visual Cue Deprivation for the Head Alignment on Unilateral Neglect Patient: Case Report (편측 무시 환자에서 시각 정보 차단이 머리 위치 정렬에 미치는 영향: 사례 연구)

  • Chang, Jong-Sung;Park, Jung-Mi;Lee, Mi-Young
    • Journal of the Korean Society of Physical Medicine
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    • v.8 no.3
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    • pp.337-342
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    • 2013
  • PURPOSE: The Unilateral neglect is characterized by difficulty shifting attention to the side of space opposite the brain lesion and frequently reducing use of contralesional extremities. This study was to identify whether the visual deprivation was responsible for head position on unilateral neglect patient after stroke. METHODS: A patient with left middle cerebral artery infarction participated in the study. We assessed neglect using line bisection and star cancellation test. Patient was instructed to maintain correct alignment of trunk and head in a sit position. We evaluated degree of head lateral tilting and rotation. Then, patient was blocked visual input. Also, we evaluated head position in the same way. RESULTS: He scored 3 points in the line bisection test and 9 points star cancellation test. In postural evaluation, he had deviated posture such as lateral head tilting and rotation. After visual cue deprivation, patient showed different head position which was decreased degree of head tilting and rotation. CONCLUSION: For vertical body orientation, it was used multiple sensory references including the vestibular, somatosensory, and visual system. This finding suggested that abnormal posture of neglect patient could be related to the visual input. It has important clinical implications in terms of understanding the neglect.

Experimental panoramic positioning errors for inducing condylar cutoff and superimposition of cervical vertebrae on the mandibular ramus (하악과두 잘림과 경추의 하악지 겹침을 야기하는 파노라마방사선촬영 오류)

  • Kang, Byung Cheol;Kim, Min Jong;Park, Hye Sun;Hwang, Sel Ae;Yoon, Suk Ja;Lee, Jae Seo
    • The Journal of the Korean dental association
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    • v.56 no.3
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    • pp.134-141
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    • 2018
  • Purpose: To measure the head tilting angle creating initial condylar cut-off and to find the head position inducing the superimposition of the cervical vertebrae over the mandibular ramus on panoramic radiograph. Materials and Methods: The panoramic radiographs were taken with Didactic skull on cervical spine model (Scientific GmbH, Hamburg, Germany) using Kodak 8000c Digital Panoramic radiography. For the inherent radiolucency of the plastic skull model, radiopaque 1 mm diameter lead wires were attached along the margin of the mandibular condyle, ramus, mandibular body, cervical vertebrae, and FH plane of the skull model. For measuring the head tilting angle creating the condylar head cutoff, panoramic radiographs were taken by tilting the FH plane downward in 5 degree increments. For finding the distance between transverse process of the third cervical vertebra and gonion inducing superimposition of cervical vertebrae on the mandibular ramus, panoramic radiographs were taken by decreasing the distance in 0.5 cm increments. Result and Conclusion: The condylar cutoff began to appear when the head of skull model was tilted downward by 15o. As the head tilting angle increasing, the condylar cutoff became more prominent. The superimposition of cervical vertebrae over the mandibular ramus began to appear when the distance between the gonion and third cervical vertebra was 1.0 cm. As the distance decreasing, the superimpostion became more prominent.

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Introduction to an Evaluation Method for Crashworthiness of Korean Tilting Train Express (한국형 고속틸팅열차의 충돌안전도 평가기법 소개)

  • Jung H.S.;Kwon T.S.;Koo J.S.
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2005.06a
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    • pp.318-321
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    • 2005
  • Crashworthy design of a train is a systematic approach to ensure the safety of passengers and crews in railway transportation for the prescribed accident scenarios. This approach needs new structural arrangements and designs to absorb higher levels of impact energy in a controlled manner and interior designs to minimize passenger injuries. In this paper, an evaluation method for crashworthiness of Korean tilting train express is introduced. Crush characteristics for each part of tilting train express are evaluated numerically through 3-dimensional shell element analysis with LS-DYNA. Based on a head-on collision and a level crossing collision scenarios, the crash behaviors of tilting train express are evaluated numerically using full-rake collision simulations.

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Crush Analysis of Tilting Train Express M-Car Initial Design (한국형 고속틸팅차량 구동차 설계초안의 충돌압괴특성 분석)

  • Jung Hyun-Seung;Koo Jeong-Seo;Kwon Tae-soo
    • Proceedings of the KSR Conference
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    • 2004.06a
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    • pp.738-743
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    • 2004
  • In this paper, the crush characteristic of the tilting train express M-car was estimated under a head-on collision scenario. The car body was divided into three parts - front, middle, and rear. For each part, crush-force relation was evaluated numerically using LS-DYNA 3-diementional shell element analysis. This result will be used for one-dimensional collision analysis of the full train rake.

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Experimental Study on the Whirling, Tilting and Flying Motion of the FDB Spindle System of a 3.5' HDD (3.5인치 HDD용 FDB스핀들 시스템의 훨링, 플라잉과 틸팅 거동에 관한 연구)

  • Oh, S.H.;Lee, S.H.;Jang, G.H.
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.15 no.1 s.94
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    • pp.39-45
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    • 2005
  • This research develops an experimental method to measure the motion of a FDB spindle system with a 3.5' disk by using three capacitance probes fixed on the xyz-micrometers, and it shows that a FDB spindle system has the whirling, flying and tilting motion. It also shows that the whirling, flying and tilting motion converge very quickly to the steady state at the same time when the rotor reaches the steady-state speed. However, they are quite large even at the steady state when they are compared with the 10nm flying height of a magnetic head. For the FDB spindle system used in this experiment, the whirl radius and the peak-to-peak variation of flying height and tilting angle at the steady-state speed of 7,200rpm are 0.675m, 30nm and $5.758\times10^{-3^{\circ}}$, respectively, so that the radial motion of the FDB spindle system exceeds a track pitch of a 3.5' HDD with 90,000 TPI.

Development of Detachable IORT Table for Colorectal Cancer (장착-탈거 및 경사각 조절이 가능한 대장직장암의 수술 중 방사선 치료대의 개발)

  • Kim, Myung-Se;Lee, Joon-Ha
    • Radiation Oncology Journal
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    • v.12 no.1
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    • pp.117-121
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    • 1994
  • In spite of remarkable improvement of surgical skills and anesthesia, local failure still occurred in 36-45$ \% $ of locally advanced colorectal cancer after curative resection with or without pre-or post-operative irradiation. Intraoperative radiation therapy(IORT) is the ideal modality which resectable lesions are removed surgically 3nd the remaining cancer nests are sterilized by irradiation during a surgical procedure. Therefore, the excellent local control without the damage of the adjacent normal tissues can be achieved. In IORT, judicious set up of the treatment cone on the treatment surface of the patient is required for accurate and homogenous dose distribution within treatment field, especially on the slopping surface of sacrum and pelvic sidewall which are the common sites of the local recurrence in rectal cancer. For this purpose, adequate co-ordination of gantry rotation and table tilting are essential. Adjusting gantry rotation is not difficult but tilting of the table is impossible inconventional treatment couch. Department of Therapeutic Radiology in Yeungnam University Medical Center developed the IORT table for colorectal cancer which is easy to set up and detach on the Linac treatment couch within 5 minutes. The range of tilting with head-up and head-down is about 30 degree which is efficient and easy-to-use, not only for IORT but also for colorectal surgery. So far, authors performed IORT with newly developed treatment table in 2 patients with rectal cancer and we found that this newly developed table could contribute in improving the dose distribution of IORT and surgical procedure for colorectal cancer.

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