• 제목/요약/키워드: Head tilting

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

  • 김대건;김상현
    • 한국방사선학회논문지
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    • 제16권7호
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    • pp.857-862
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    • 2022
  • 본 연구의 목적은 토모다이렉트를 이용한 토모테라피 방사선치료에서 두상 각도(head tilting)에 따라 3차원 입체조형 전뇌 방사선치료 계획을 평가하고 자 하였다. 총 다섯 가지 두상 각도(-20°, -10°, 0°, +10°, +20°)를 비교 평가하였다. 두상 각도에 따라 표적에 대한 선량균질지수(homogeneity index, HI)와 처방선량지수(conformity index, CI)를 계산하였고, 정상 장기인 수정체, 안구, 귀밑샘에 대한 최대선량과 평균 선량을 구하였다. 선량균질지수와 처방선량지수는 두상 각도가 +10°와 +20°에서 수치 1에 가까웠다. 두상 각도 +10°에서 수정체와 안구의 선량은 기준 두상각도(0°)에 비해 각각 약 74%와 30% 감소하였다. 턱을 올린 상태의 +10°의 두상 각도는 표적에 대한 선량균일지수와 처방선량지수가 적합하며 렌즈와 안구의 선량을 줄일 수 있는 각도로써 권장한다.

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

  • 이경윤;서진우;박쾌환;박민정
    • 대한추나의학회지
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    • 제5권1호
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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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체위변화에 수반되는 심맥관계반응에 관한연구 (A Study of Circulatory Responses to Postural Changes)

  • 서석완;채의업
    • The Korean Journal of Physiology
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    • 제5권2호
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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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편측 무시 환자에서 시각 정보 차단이 머리 위치 정렬에 미치는 영향: 사례 연구 (The Effect of Visual Cue Deprivation for the Head Alignment on Unilateral Neglect Patient: Case Report)

  • 장종성;박정미;이미영
    • 대한물리의학회지
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    • 제8권3호
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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.

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

  • 강병철;김민종;박혜선;황슬애;윤숙자;이재서
    • 대한치과의사협회지
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    • 제56권3호
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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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한국형 고속틸팅열차의 충돌안전도 평가기법 소개 (Introduction to an Evaluation Method for Crashworthiness of Korean Tilting Train Express)

  • 정현승;권태수;구정서
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2005년도 춘계학술대회 논문집
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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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한국형 고속틸팅차량 구동차 설계초안의 충돌압괴특성 분석 (Crush Analysis of Tilting Train Express M-Car Initial Design)

  • 정현승;구정서;권태수
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2004년도 춘계학술대회 논문집
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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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3.5인치 HDD용 FDB스핀들 시스템의 훨링, 플라잉과 틸팅 거동에 관한 연구 (Experimental Study on the Whirling, Tilting and Flying Motion of the FDB Spindle System of a 3.5' HDD)

  • 오승혁;이상훈;장건희
    • 한국소음진동공학회논문집
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    • 제15권1호
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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.

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

  • 김명세;이준하
    • Radiation Oncology Journal
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    • 제12권1호
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    • pp.117-121
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    • 1994
  • 연구목적 : 국소재발을 줄이면서 합병증을 최소화하기 위한 방법으로 제안된 수술중 방사선 치료(IORT)는 육안으로 치료 범위를 확인 할 수 있는 이점이 있으나 조사 선축의 각도와 치료과 치료면의 거리 등이 조금만 틀려도 조사야의 선량에 차이가 있을 뿐 아니라 조사방사선의 동질성(Homogeneity)에도 영향을 미치게 된다. 직장암의 경우 조사 부위가 대부분에서 3차적인 경사면을 가진 골반벽이 됨으로 치료 cone의 정확한 Set-up은 적절한 gantry의 회전과 치료대(treatment couch)의 tilting이 조화되어야만 가능하다. gantry의 회전은 어느 기계에서나 가능하나 치료대의 tilting은 대부분에서 불가능함으로 영남대학교 의료원 치료 방사선과에서는 상하로의 tilting이 30$ ^{\circ} $까지 가능할 뿐 아니라 기존 치료대에 장착과 탈거가 5분이내에 쉽게 될수 있는 치료대를 개발하기 위함. 재료 및 방법 : IORT 치료대는 2cm 두께의 bekelite로 2cm 두께의 sponge를 leather로 싸서 수술대에 피나 기타용액이 스며들지 못하게 하였고 전체의 무게가 45kg을 넘지 않도록 하여 치료대의 양끝에 장착할 경우, 치료대의 수평이 유지되도록 하였다. 상하 경사각은 30$ ^{\circ} $를 유지토륵 하였고 lithotomy position에서도 side handle을 사용하여 경사각 조절이 가능토록 하였다. 결과 및 결론 : 1992년 9월부터 1993년 3월까지 여러번의 수정을 거친 후 대장 직장암의 IORT에 사용하고 있으며, 3차원적인 골반벽에의 정확한 접근(approach)이 가능할 뿐 아니라 기존 방사선 치료대에 장착과 탈거가 5분 이내에 가능하며, 상하 경사각 30$ ^{\circ} $ 정도로의 조절이 수술이나 마취에 전혀 영향을 주지 않는 상태에서 자유로이 조절 되므로 향후 대장직장암의 IORT에 크게 공헌할 수 있을 것으로 사료됨.

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