• Title/Summary/Keyword: 인공삽입물

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Tumor Prosthetic Arthroplasty and Arthroplasty with Bone Cement for the Metastatic Malignant Bone Tumor in the lower Extremity (하지 관절 부위에 발생한 전이성 종양 환자의 종양 대치물 및 골시멘트와 인공관절 삽입술)

  • Yang, Jun-Young;Lee, June-Kyu;Hwang, Deuk-Soo;Shin, Hyun-Dae;Kwak, Sang-Koo;Kim, Kyung-Cheon;Nam, Dae-Cheul
    • The Journal of the Korean bone and joint tumor society
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    • v.9 no.1
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    • pp.12-17
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    • 2003
  • Purpose: In this report we are going to discuss about the functional evaluation and the outcome of treatment of metastatic tumor in the lower extremities treated with tumor prosthetic arthroplasty. Materials and Methods: This report is based on nine patients diagnosed as a metastatic tumor and treated by tumor prosthetic arthroplasty, from June 1998 to December 2001. Age of the patients ranged from 49 to 63 with the average of 56.3. The average follow up period was 23.4 months. Two patients had lung cancer, three had breast cancer, two had renal cancer, one colon cancer, and one had multiple myeloma. All these were primary cancers. The site of metastasis were six in proximal femur, two in distal femur, and one in proximal tibia. Tumor excision was performed after biopsy in following the principle of primary tumor management. Excision with wide surgical margin was tried as possible could. Six cases were treated with tumor prosthesis, and the other three cases were reconstructed with bone cement and arthroplasty. Results: The functional evaluation in the extremities at the last follow up was performed on Enneking evaluation score with 6 categories. The highest scored 26, and the lowest scored 10, with an average of 19.5. A case in which the patient died 15 days after the operation was excluded from the evaluation. Among the categories, emotional acceptance to postoperative function and pain relief were highly scored. At the final follow up, seven patients survived, and one colon cancer patient died 68 days after operation. Conclusion: Metastatic tumor occurring in joints of lower extremities could be treated in accordance to the treatment principle of primary tumor. By insertion of tumor prosthesis, we can get satisfactory results of function in the lower extremity and pain relief especially. So, this aspect of medical favor must be considered in treating patients.

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Reduction of Metal Artifact by Using VAT-SEMAC in MRI (VAT-SEMAC을 이용한 보철물에 의한 허상 감소)

  • Kim, Hyung-Tae;Lim, Jong-Nam;Chon, Kwon Su
    • Journal of the Korean Society of Radiology
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    • v.13 no.2
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    • pp.227-232
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    • 2019
  • MRI examination for patients with metal objects has in poor image quality. Metallic implants can result in poor image because magnetic susceptibility causes signal loss and distortion and makes poor imaging, which is called magnetic susceptibility artifact or metal artifact. There are several approaches to reduce metal artifacts. In this study, we study the reduction of metal artifact by VAT and SEMAC techniques. A metal implant used for orthopedic surgery was attached to the phatom and the distortion caused by the artifact was measured under T1WI and T2WI protocols. Several techniques of VAT only and VAT and SEMAC for the reduction of metal artifact were compared. The metal artifact showed a reduction of at least 8% to a maximum of 26% in the VAT-SEMAC. The VAT-SEMAC technique can be applied to patients with orthopedic implants to improve image quality. If scan time and image quality are simultaneously considered in VAT-SEMAC technique, metal artifact will be reduced in clinical practice.

A Study of the Metal Artifact Reduction using Dual Energy CT : Clinical Applications of Dual Energy and MAR Algorithm (Dual Energy CT를 이용한 금속물질 인공물 감소방법 : Dual Energy와 MAR알고리즘의 임상적 응용)

  • Park, Ki Seok;Choi, Woo Jeon;Kim, Dong Hyun
    • Journal of the Korean Society of Radiology
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    • v.15 no.3
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    • pp.273-279
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    • 2021
  • Metal material inserted into the body have a large difference in density from human tissues or bones around the Metal during CT scans.. Therefore, the Metal material inserted into the body produces Artifact. Metal Artifact, which occurs around Metals, can degrade the quality of CT images, causing confusion when medical team diagnose lesions. Through this experiment, we confirm that the occurrence of Artifacts decrease by using Dual energy CT and MAR algorithm in Single source Dual energy CT. We also want to present basic data on clinical application methods by comparing and analyzing the characteristics of images obtained by each method. Using GE 750HD CT, artificial implants were scanned using general method and Dual energy. Then we apply the MAR algorithm to each image obtained. And all previously acquired images were compared and analyzed the characteristics of the examination, such as image quality evaluation and dose evaluation. Images with MAR algorithm and Dual Energy confirmed a decrease in Metal Artifact. Images with MAR algorithm have reduced Metal Artifact, but have the disadvantage of distorting the details of artificial joint implants. On the other hand images teseted with Dual Energy have the advantage of being able to implement details than those applied with MAR algorithms, it takes longer to reconstruct the image and the exposure dose was about four times higher than those applied with MAR algorithm. In order to locate Metals, such as the post-operative follow-up period, it is useful to apply MAR algorithm to obtain images. And it is more useful to examine with Dual Energy when micro lesion identification, such as cardiac examination, and surgical planning or when tests are performed in diagnostic way.

Total Hip Arthroplasty in Patients with Avascular Necrosis of the Entire Femur (전체 대퇴골에 발생한 골괴사 환자에서 인공 고관절 전치환술)

  • Yi, Seung Rim;Im, Se Hyuk;Park, Sang Hoon
    • Journal of the Korean Orthopaedic Association
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    • v.54 no.3
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    • pp.281-286
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    • 2019
  • Avascular necrosis (AVN) is defined as the cellular death of bone and bone marrow components due to the loss of blood supply, and associated with post-traumatic or non-traumatic events. AVN usually involves the epiphysis of a long bone, such as the femoral and humeral heads, which are susceptible to osteonecrosis. Many studies have been conducted but they were restricted to investigations of femoral head avascular necrosis. The presence of osteonecrosis in the proximal femur may impair biological fixation after total hip arthroplasty. We report a 56-year-old male patient with avascular necrosis located not only at the femoral head, but also in the entire femur, including the medullary cavity, who underwent total hip arthroplasty 2 years earlier along with a review of the relevant literature.

The Effects of Physical States of Phospholipids on $Ca^{2+}$-ATPase Activity of Biological Membranes (지질의 물리학적 성상이 $Ca^{2+}$-ATPase 활성도에 미치는 영향)

  • Hah, Jong-Sik
    • The Korean Journal of Physiology
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    • v.22 no.2
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    • pp.163-177
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    • 1988
  • The $Ca^{2+}-ATPase$ of sarcoplasmic reticulum (SR) was solubilized and reconstituted into a mixture of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) of varying ratios in order to assess the effect of physical states of phospholipids on the incorporation and functions $Ca^{2+}-ATPase$. On the basis of the spectral data of Ca-arsenazo III, the $Ca^{2+}$ uptake of SR was increased linearly as the PC content increased in the reconstituted vesicles. The ATP hydrolysis activity also increased as PC content increased up to 25% and then decreased slightly as the PC content further increased. On the other hand the incorporation of $Ca^{2+}-ATPase$ into the reconstituted vesicls occured maximally at 25% PC and 75% PE mixture which is known to have a non-bilayer structure in reconstitution system. From the above results it is clear that preexisting defects in the lipid bilayer promote protein incorporation into the bilayer during reconstitution and lamellar structure of the bilayer facilitates the $Ca^{2+}-ATPase$ function.

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Measurement of Material Properties of Composites under High Temperature using Fiber Bragg Grating Sensors (광섬유 브래그 격자 센서를 이용한 고온용 복합재료의 물성 측정)

  • 강동훈;박상욱;김수현;홍창선;김천곤
    • Composites Research
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    • v.16 no.6
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    • pp.41-47
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    • 2003
  • Composites are widely used for aircraft, satellite and other structures due to its good mechanical and thermal characteristics such as low coefficient of thermal expansion(CTE), heat-resistance, high specific stiffness and specific strength. In order to use composites under condition of high temperature, however, material properties of composites at high temperatures must be measured and verified. In this paper, material properties of T700/Epoxy were measured through tension tests of composite specimens with an embedded FBG sensor in the thermal chamber at the temperatures of RT, $100^{\circ}$, $200^{\circ}$, $300^{\circ}$, $300^{\circ}$. Through the pre-test of an embedded optical fiber, we confirmed the embedding effects of an optical fiber on material properties of the composites. Two kinds of specimens of which stacking sequences are [0/{0}/0]$_{T}$. and [$90_2$/{0}/$90_2$]. were fabricated. From the experimental results, material property changes of composites were successfully shown according to temperatures and we confirmed that fiber Bragg grating sensor is very appropriate to strain measurement of composites under high temperature.

Three-Dimensional Printing Technology in Orthopedic Surgery (정형외과 영역에서의 삼차원 프린팅의 응용)

  • Choi, Seung-Won;Park, Kyung-Soon;Yoon, Taek-Rim
    • Journal of the Korean Orthopaedic Association
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    • v.56 no.2
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    • pp.103-116
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    • 2021
  • The use of 3-dimensional (3D) printing is becoming more common, and its use is increasing in the orthopedic surgery. Currently, there are four major methods of using 3D printing technology in orthopedic surgery. First, surgical planning simulation using 3D printing model; second, patient-specific surgical instruments; third, production of customized prosthesis using 3D printing technique; fourth, patient-specific prosthesis produced by 3D printing. The areas of orthopedic surgery where 3D printing technology can be used are shoulder joint, spine, hip and pelvis, knee joints, ankle joint, and tumors. Since the diseases and characteristics handled by each area are different, the method of using 3D printing technology is also slightly different in each area. However, using 3D printing technology in all areas can increase the efficiency of surgery, shorten the surgery time, and reduce radiation exposure intraoperatively. 3D printing technology can be of great help in treating patients with particularly complex and difficult orthopedic diseases or fractures. Therefore, the orthopedic surgeon should make the most of the benefits of the 3D printing technology so that patient can be treated effectively.

Limb Salvage Using a Combined Distal Femur and Proximal Tibia Replacement in the Sequelae of an Infected Reconstruction on Either Side of the Knee Joint (슬관절 주위 재건물 감염 후유증 시 슬관절 상하부 종양인공관절을 이용한 사지 구제술)

  • Jeon, Dae-Geun;Cho, Wan Hyeong;Park, Hwanseong;Nam, Heeseung
    • Journal of the Korean Orthopaedic Association
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    • v.54 no.1
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    • pp.37-44
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    • 2019
  • Purpose: Tumor infiltration around the knee joint or skip metastasis, repeated infection sequelae after tumor prosthesis implantation, regional recurrence, and mechanical failure of the megaprosthesis might require combined distal femur and proximal tibia replacement (CFTR). Among the aforementioned situations, there are few reports on the indication, complications, and implant survival of CFTR in temporarily arthrodesed patients who had a massive bony defect on either side of the knee joint to control infection. Materials and Methods: Thirty-four CFTR patients were reviewed retrospectively and 13 temporary arthrodesed cases switched to CFTR were extracted. All 13 cases had undergone a massive bony resection on either side of the knee joint and temporary arthrodesis state to control the repeated infection. This paper describes the diagnosis, tumor location, number of operations until CFTR, duration from the index operation to CFTR, survival of CFTR, complications, and Musculoskeletal Tumor Society (MSTS) score. Results: According to Kaplan-Meier plot, the 5- and 10-year survival of CFTR was 69.0%±12.8%, 46.0%±20.7%, respectively. Six (46.2%) of the 13 cases had major complications. Three cases underwent removal of the prosthesis and were converted to arthrodesis due to infection. Two cases underwent partial change of the implant due to loosening and periprosthetic fracture. The remaining case with a deep infection was resolved after extensive debridement. At the final follow-up, the average MSTS score of 10 cases with CFTR was 24.6 (21-27). In contrast, the MSTS score of 3 arthrodesis cases with failed CFTR was 12.3 (12-13). The average range of motion of the 10 CFTR cases was 67° (0°-100°). The mean extension lag of 10 cases was 48° (20°-80°). Conclusion: Although the complication rates is substantial, conversion of an arthrodesed knee to a mobile joint using CFTR in a patient who had a massive bony defect on either side of the knee joint to control infection should be considered. The patient's functional outcome was different from the arthrodesed one. For successful conversion to a mobile joint, thorough the eradication of scar tissue and creating sufficient space for the tumor prosthesis to flex the knee joint up to 60° to 70° without soft tissue tension.

The effects of labeling gap and susceptibility artifacts in pCASL perfusion MRI (pCASL 관류 영상에서 표지 간격과 자화감수성 인공물이 영상에 미치는 영향)

  • Kim, Seong-Hu
    • Journal of the Korean Society of Radiology
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    • v.9 no.4
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    • pp.213-217
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    • 2015
  • To report problems found in a patient who has implemented stent implantation and then conducted a perfusion MRI using ASL(Arterial Spin Labeling), in order to suggest a solution to them. The perfusion MRI was conducted, using pCASL among ASL methods. Data from pCASL(Pseudo Continuous Arterial Spin Labeling) was acquired together with the structural image simply by changing position(labeling gap 15 mm, 170 mm) of the labeling pulse to avoid stent. Data was processed through the ASLtbx. When perfusion MRI was acquired using pCASL, it showed that the position of the conventional labeling pulse (labeling gap 24 mm) was overlapped with that of stent, which made signal intensity in right brain tissue appear as if it were void. When the labeling pulse was positioned (labeling gap 15 mm) to avoid stent, high signal intensity images were acquired. In labeling pulse (labeling gap 170 mm), the signal intensity was more reduced due to relaxation before labeled blood arrived at the imaging slice. pCASL can be stably repeated measurements because it does not use a contrast agent. And it should be selected with the appropriate image acquisition parameters for the high quality image.

The usability of the image according to the frequency encoding gradient direction conversion in fixation using the non magnetic metal screw (비 자성 금속 screw를 이용한 고정술에서 주파수 부호화 경사 방향 변환에 따른 영상의 유용성)

  • Cho, Jae-Hwan;Lee, Hae-Kag;Park, Cheol-So
    • Journal of Digital Contents Society
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    • v.12 no.1
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    • pp.49-55
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    • 2011
  • Because of causing the geometrical transformation of the magnetic field, the patient implementing the fixation using the nonmagnetic metal screw causes the magnetic susceptibility artifact at an image. Thus, in this research, the distortion measure of the image according to the frequency oblique direction conversion tried to be compared in the magnetic susceptibility artifact occurence. First, the itself phantom inserting the nonmagnetic metal screw of the titanium component was made and the region of interest was set up and the frequency oblique direction the anterior - back side was converted to the right-to-left direction in the axial image and a right-to-left was converted to the upper side - bottom side in the coronal plane and the upper - bottom side was converted to the anterior - back side in the sagittal plane and the distortion measure of the region of interest was compared, it observed. In a result, when converting the frequency oblique direction, the distortion difference of the region of interest could be confirmed and it is considered to enhance the diagnostics efficiency changing the oblique direction appropriately.