• Title/Summary/Keyword: fixation point

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Anatomic Consideration of the C1 Laminar Arch for Lateral Mass Screw Fixation via C1 Lateral Lamina : A Landmark between the Lateral and Posterior Lamina of the C1

  • Kim, Jung-Hwan;Kwak, Dai-Soon;Han, Seung-Ho;Cho, Sung-Min;You, Seung-Hoon;Kim, Moon-Kyu
    • Journal of Korean Neurosurgical Society
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    • v.54 no.1
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    • pp.25-29
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    • 2013
  • Objective : To clarify the landmark for deciding the entry point for C1 lateral mass screws via the posterior arch by using 3-dimensional (3D) computed images. Methods : Resnick insisted that the C1 posterior arch could be divided into pure posterior and lateral lamina (C1 pedicle). Authors studied where this transition point (TP) is located between the posterior lamina and the C1 pedicle and how it can be recognized. The 3D computed images of 86 cadaver C1s (M : F=45 : 41) were used in this study. Results : The superior ridge of the C1 posterior arch had 2 types of orientation. One was in the vertical direction in the C1 posterior lamina and the other was in the horizontal direction in the C1 pedicle. The TP was located at the border between the 2 areas, the same site as the posterior end of the groove of the vertebral artery. On posterior-anterior projection, the posterior arch was sharpened abruptly at TP. We were unable to identify the TP in 6.4% of specimens due to complete or partial osseous bridges. A total of 93.8% of the TP were located between the most enlarged point of the spinal canal and the medial wall of the vertebral artery. Conclusion : The anatomic entry zone of C1 lateral laminar screws was clarified and identified based on the TP by using preoperative 3D computed images.

Bony Stability and Soft Tissue Changes after Orthognathic Surgery on Patients with Cleft (구순구개열 환자의 악교정 수술 후의 골조직 안정도와 연조직 변화율)

  • Shin, Heakyeong;Hsieh, Yuh-Jia;Liao, Yu-Fang;Lo, Lun-Jou;Jo, Myoung-Soo
    • Archives of Craniofacial Surgery
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    • v.13 no.1
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    • pp.4-10
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    • 2012
  • Purpose: The objective of this retrospective study was to assess the skeletal stability after orthognathic surgery for patients with cleft lip and palate. The soft tissue changes in relation to the skeletal movement were also evaluated. Methods: Thirty one patients with cleft received orthognathic surgery by one surgeon at the Craniofacial Center, Chang Gung Memorial Hospital, Taoyuan, Taiwan. Osseous and soft tissue landmarks were localized on lateral cephalograms taken at preoperative (T0), postoperative (T1), and after completion of orthodontic treatment (T2) stages. Surgical movement (T0.T1) and relapse (T1.T2) were measured and compared. Results: Mean anteroposterior horizontal advancement of maxilla at point A was 5.5 mm, and the mean horizontal relapse was 0.5 mm (9.1%). The degree of horizontal relapse was found to be correlated to the extent of maxillary advancement. Mean vertical lengthening of maxilla at point A was 3.2 mm, and the mean vertical relapse was 0.6 mm (18.8%). All cases had maxillary clockwise rotation with a mean of 4.4 degrees. The ratio for horizontal advancement of nasal tip/anterior nasal spine was 0.54/1, and the ratio of A' point/A point was 0.68/1 and 0.69/1 for the upper vermilion/upper incisor tip. Conclusion: Satisfactory skeletal stability with an acceptable relapse rate was obtained from this study. High soft tissue to skeletal tissue ratios were obtained. Two-jaw surgery, clockwise rotation, rigid fixation, and alar cinch suture appeared to be the contributing factors for favorable results.

Preventing Varus Deformity in Senile Patients with Proximal Humerus Fractures and Poor Medial Support

  • Kim, Young-Kyu;Kang, Suk-Woong;Kim, Jin-Woo
    • Clinics in Shoulder and Elbow
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    • v.19 no.4
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    • pp.216-222
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    • 2016
  • Background: We investigated the effectiveness of fibular strut allograft augmentation of proximal humerus fractures to prevent varus deformity in patients over the age of 65 years with insufficient medial support. Methods: We analyzed the clinical and radiological outcomes of locking plate fixation with adjunct fibular strut allograft augmentation in 21 patients with proximal humeral fractures. The inclusion criteria were age (65-year-old or older); presence of severe medial comminution; inadequate medial support; and those who could participate in at least a one year follow-up. The average age was 76.4 years. We analyzed each patient's Constant score, our indicator of clinical outcome. As radiological parameters, we analyzed time-to-bone union; restoration of the medial hinge; difference between the immediately postoperative and the last follow-up humeral neck-shaft angles;; and anatomical reduction status, which was assessed using the Paavolainen method. Results: A successful bone union was achieved in all patients at an average of 11.4 weeks. We found that the average Constant score was 74.2, showing a satisfactory outcome. The average difference in the humeral neck-shaft angles between the immediately postoperative time-point and at the final follow-up was $3.09^{\circ}$. According to the Paavolainen method, the anatomical reduction was rated excellent. The medial hinge was restored in 14 of 21 patients. Although we did not find evidence for osteonecrosis, we found that a single patient had a postoperative complication of screw cut-out. Conclusions: Fibular strut allografting as an adjunct treatment of proximal humeral fractures may reduce varus deformity in patients with severe medial comminution.

Tarsodermal Suture Fixation Preceding Redundant Skin Excision: A Modified Non-Incisional Upper Blepharoplasty Method for Elderly Patients

  • Yoon, Hong Sang;Park, Bo Young;Oh, Kap Sung
    • Archives of Plastic Surgery
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    • v.41 no.4
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    • pp.398-402
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    • 2014
  • Background Non-incisional blepharoplasty is a simple, less invasive method for creating a more natural-appearing double eyelid than classical incisional blepharoplasty. However, in aging patients, non-incisional blepharoplasty is not effective due to more severe blepharochalasis. Traditionally, incisional blepharoplasty is a common surgical method used for older patients, but blepharoplasty in elderly patients typically results in prolonged recovery times, and final blepharoplasty lines may be located in unintended or asymmetrical positions. Here, we introduce a new modified combination technique for geriatric blepharoplasty. Methods A total of ten patients were treated from July 2010 through July 2012 using the combination method. First, we performed non-incisional blepharoplasty using tarsodermal fixation. Then, incisional blepharoplasty with additional elliptical excision of the upper eyelid skin was performed. We removed pretarsal tissue, fat, the orbicularis oculi muscle, and orbital fat. Telephone surveys were administered to all patients for follow-up. The questionnaire was composed of eight questions that addressed recurrence and satisfaction with aesthetics and the procedure. Results A total of nine patients (90%) responded to the telephone survey. All cases of moderate to severe blepharochalasia were corrected and there were no major complications. Patients who underwent blepharoplasty had higher satisfaction scores. All patients were satisfied with the postoperative shapes of their eyelids. Conclusions The advantages of the proposed technique include: ease of obtaining a natural-looking fold with symmetry at the desired point; reproducible methods that require short operation times; fast postoperative recovery that results in a natural-appearing double-eyelid line; and high patient satisfaction.

Transcutaneous medial fixation sutures for free flap inset after robot-assisted nipple-sparing mastectomy

  • Kim, Bong-Sung;Kuo, Wen-Ling;Cheong, David Chon-Fok;Lindenblatt, Nicole;Huang, Jung-Ju
    • Archives of Plastic Surgery
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    • v.49 no.1
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    • pp.29-33
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    • 2022
  • The application of minimal invasive mastectomy has allowed surgeons to perform nipples-paring mastectomy via a shorter, inconspicuous incision under clear vision and with more precise hemostasis. However, it poses new challenges in microsurgical breast reconstruction, such as vascular anastomosis and flap insetting, which are considerably more difficult to perform through the shorter incision on the lateral breast border. We propose an innovative technique of transcutaneous medial fixation sutures to help in flap insetting and creating and maintaining the medial breast border. The sutures are placed after mastectomy and before flap transfer. Three 4-0 nylon suture loops are placed transcutaneously and into the pocket at the markings of the preferred lower medial border of the reconstructed breast. After microvascular anastomosis and temporary shaping of the flap on top of the mastectomy skin, the three corresponding points for the sutures are identified. The three nylon loops are then sutured to the dermis of the corresponding medial point of the flap. The flap is placed into the pocket by a simultaneous gentle pull on the three sutures and a combined lateral push. The stitches are then tied and buried after completion of flap inset.

Differences in the Control of Anticipation Timing Response by Spatio-temporal Constraints

  • Seok-Hwan LEE;Sangbum PARK
    • Journal of Sport and Applied Science
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    • v.7 no.2
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    • pp.39-51
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    • 2023
  • Purpose: The purpose of this study was to investigate differences in the control process to satisfy spatial and temporal constraints imposed upon the anticipation timing response by analyzing the effect of spatio-temporal accuracy demands on eye movements, response accuracy, and the coupling of eye and hand movements. Research design, data, and methodology: 12 right-handed male subjects participated in the experiment and performed anticipation timing responses toward a stimulus moving at three velocities (0.53m/s, 0.66m/s, 0.88m/s) in two task constraint conditions (temporal constraint, spatial constraint). During the response, response accuracy and eye movement patterns were measured from which timing and radial errors, the latency of saccade, fixation duration of the point of gaze (POG), distance between the POG and stimulus, and spatio-temporal coupling of the POG and hand were calculated. Results: The timing and radial errors increased with increasing stimulus velocity, and the spatio-temporal constraints led to larger timing errors than the temporal constraints. The latency of saccade and the temporal coupling of eye and hand decreased with increasing stimulus velocity and were shorter and longer respectively in the spatio-temporal constraint condition than in the temporal constraint condition. The fixation duration of the POG also decreased with increasing stimulus velocity, but no difference was shown between task constraint conditions. The distance between the POG and stimulus increased with increasing stimulus velocity and was longer in the temporal constraint condition compared to the spatio-temporal constraint condition. The spatial coupling of eye and hand was larger with the velocity 0.88m/s than those in other velocity conditions. Conclusions: These results suggest that differences in eye movement patterns and spatio-temporal couplings of stimulus, eye and hand by task constraints are closely related with the accuracy of anticipation timing responses, and the spatial constraints imposed may decrease the temporal accuracy of response by increasing the complexity of perception-action coupling.

Visual Image Effects on Sound Localization in Peripheral Region under Dynamic Multimedia Conditions

  • Kono, Yoshinori;Hasegawa, Hiroshi;Ayama, Miyoshi;Kasuga, Masao;Matsumoto, Shuichi;Koike, Atsushi;Takagi, Koichi
    • Proceedings of the IEEK Conference
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    • 2002.07a
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    • pp.702-705
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    • 2002
  • This paper describes effects of visual information influencing sound localization in the peripheral visual Held under dynamic conditions. Presentation experiments of an audio-visual stimulus were carried out using a movie of a moving patrol car and its siren sound. The tallowing results were obtained: first, the sound image on the timing at the beginning of the presentation was more strongly captured by the visual image than that at the end, i.e., the "beginning effect" was occurred; second, in the peripheral regions, the "beginning effect" was strongly appeared in near the fixation point of eyes.

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The Experience of Open Reduction and Internal Fixation of Mandible Fracture by Acupuncture Method (Acupuncture를 이용한 하악골 골절수술경험 -증례 보고-)

  • Khil, Hong-Mo;Kwak, Ho-Sung;Ro, Shik
    • The Korean Journal of Pain
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    • v.9 no.1
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    • pp.195-199
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    • 1996
  • Based on points of neuroendocrine physiology, stimulus developed at the acupuncture site can pass to the pituitary gland through somatosensory and activated descending inhibitory mechanism which originated in raphe magnus of midbrain. For the operation of mandible fracture, acupuncture anesthesia was performed at 6 points of both forearm and both feet by method taking point on distant segment. Acupuncture anesthesia deals with central analgesic mechanism and the theory of diffuse noxious inhibitory control.

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Analysis of convergent looking stereo camera model (교차 시각 스테레오 카메라 모델 해석)

  • 이적식
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.33B no.10
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    • pp.50-62
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    • 1996
  • A parallel looking stereo camera was mainly used as an input sensor for digital image processing, image understanding and the extraction of 3 dimensional information. Theoretical analysis and performance evaluation are dealt in this paper for a convergent looking stereo camera model having a fixation point with the result of crossing optical axes. The quantization error, depth resolution and equidepth map due to digital pixels, and the misalignments effects of pan, tilt and roll angles are analyzed by using rhe relationship between the reference and image coordinate systems. Also horopter, epipolar lines, probability density functions of the depth error, and stereo fusion areas for the two camera models are discussed.

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Activation-based Strategy and Spatial Strategy in Visual Search (시각탐사에서 활성화 기반 전략과 공간적 전략)

  • Lee, KangWoo;Shin, Myoung-Hee
    • Proceedings of the Korean Society of Computer Information Conference
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    • 2014.01a
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    • pp.149-151
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    • 2014
  • 주의(attention)를 어떻게 할당하는가는 정신물리학뿐만 아니라, 컴퓨터 시각과정을 모델링하는데 중요한 주제 중 하나이다. 기존 연구는 saliency와 같은 활성화 값에 의해서 주의탐사 순위가 결정된다. 본 논문에서는 주의탐사과정을 병렬처리를 통한 활성화 값 추출과정과 순차적 처리를 통한 공간적 전략과정으로 구분하였다. 단서패러다임에 기초한 계산모형을 이용하여, 실제 인간의 수행결과를 AUC와 Levenshtein 척도를 이용하여 비교하였다. Fixation point 비교에서는 인간과 활성화를 기반으로 한 계산모형의 수행은 높은 상관성을 가지고 있었다. 주의궤적 혹은 scanpath 분석에서는 활성화기반 전략보다는 공간적 전략 모형이 더 높은 유사성을 보였다. 이는 주의탐사과정이 병렬처리과정을 통해 얻어진 saliency에 의해서만 결정되는 것이 아니라, 목표물간의 근접성 등의 공간적 전략을 통해 순차적 (sequential) 경로가 생성됨을 의미한다.

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