• Title/Summary/Keyword: Magnetic Materials

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Usefulness of $^{99m}Tc$-labeled RBC Scan and SPECT in the Diagnosis of Head and Neck Hemangiomas (두경부 혈관종 진단시 $^{99m}Tc$-RBC Scan and SPECT 검사의 유용성)

  • Oh, Shin-Hyun;Roh, Dong-Wook;Ahn, Sha-Ron;Park, Hoon-Hee;Lee, Seung-Jae;Kang, Chun-Goo;Kim, Jae-Sam;Lee, Chang-Ho
    • The Korean Journal of Nuclear Medicine Technology
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    • v.12 no.1
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    • pp.39-43
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    • 2008
  • Purpose: There are various methods to diagnose hemangioma, such as ultrasonography (US), computed tomography (CT), magnetic resonance imaging (MRI) and nuclear medicine. However, by development of SPECT imaging, the blood-pool scan using $^{99m}Tc$-labeled red blood cell has been used, because it was non-invasive and the most economical method. Therefore, in this study, we proposed that the usefulness of $^{99m}Tc$-RBC scan and SPECT of the head and neck to diagnose unlocated hemangiomas. Materials and Methods: $^{99m}Tc$-RBC scan and SPECT was performed on 6 patients with doubtful hemangioma (4 person, head; 1 person, neck; 1 person, another). We labeled radiopharmaceutical using modified in vivo method and then, centrifuged it to remove plasma. After a bolus injection of tracer, dynamic perfusion flow images were acquired. Then, anterior, posterior, both lateral static blood-pool images were obtained as early and 4 hours delayed. SPECT was progressed 64 projections per 30 seconds. Each image was interpreted by physicians, Nuclear medicine specialist, and technologist blinded to patient's data. Results: In 5 patients of all the radioactivity of doubtful site didn't change in flow images, but, in blood-pool, delayed and SPECT images, it was increased. So, it was a typical hemangioma finding. The size of lesion was over 2 cm, and it could discriminate as comparing to the delayed and SPECT imaging. On the other hand, in 1 patient, the radioactivity was increased in blood-pool images, but, not in delayed and SPECT images, so, it was proved no hemangioma. Conclusion: Using $^{99m}Tc$-RBC Scan and SPECT, we could diagnose the hemangiomas in head and neck, as well as, liver, more non-invasive, economical, and easy. Therefore, it considered that $^{99m}Tc$-RBC scan and SPECT would offer more useful information for diagnosis of hemangioma, rather than otherimaging such as US, CT, MRI.

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Immunomodulatory Effects of β-sitosterol and Daucosterol Isolated from Dioscorea batatas on LPS-stimulated RAW 264.7 and TK-1 Cells (산약에서 분리한 β-sitosterol과 daucosterol의 RAW 264.7 세포와 TK-1 세포에서의 면역 활성 조절 효능)

  • Park, Min-Kyung;Cho, Sehee;Ahn, Tae-Kyu;Kim, Do-Hyun;Kim, So-Yeon;Lee, Jin-Wook;Kim, Jee-In;Seo, Eul-Won;Son, Kun-Ho;Lim, Jae-Hwan
    • Journal of Life Science
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    • v.30 no.4
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    • pp.359-369
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    • 2020
  • Although many studies on immune modulatory materials have used RAW 264.7 cells, few have used T cell-derived TK-1 cell lines. Moreover, although some studies have investigated the efficacy of plant-derived β-sitosterol, few have examined the immunomodulatory activity of its analogue, daucosterol. In this study, β-sitosterol and daucosterol were isolated from D. batatas and identified by nuclear magnetic resonance spectroscopy. To evaluate the immune-enhancing or inhibitory effects of the isolated phytosterols, the expression levels of the inflammatory response genes COX-2, TNF-α, IL-6, and iNOS were analyzed by RT-PCR. The relative expression levels of TNF-α and iNOS in RAW 264.7 cells were increased more than threefold with β-sitosterol treatment comparing to those of untreated control. In the case of TK-1 cells, the expression level of TNF-α was decreased and the expression level of iNOS was increased in a β-sitosterol concentration-dependent manner. The expression levels of COX-2, TNF-α, and IL-6 increased by approximately 0.7-1.2 times in RAW 264.7 cells treated with daucosterol compared to those of untreated control, but iNOS expression decreased by 0.8-0.18 times. In the case of daucosterol-treated TK-1 cells, the expression levels of TNF-α, IL-6, and iNOS were markedly reduced from those of TK-1 cells treated only with lipopolysaccaride. As a conclusion, β-sitosterol treatment increased TNF-α and iNOS expression levels in RAW 264.7 cells, thus exerting an immune- boosting effect. However, in TK-1 cells, iNOS expression increased while TNF-α expression decreased, indicating an immunosuppressive activity of β-sitosterol. Daucosterol appears to exert an immunosuppressive effect in both macrophages and T cell lines by inhibiting iNOS expression in RAW 264.7 cells and greatly inhibiting the expression of TNF-α, IL-6, and iNOS in TK-1 cells.

Outcome of LINAC Radiosurgery for a Cavernous Angioma (해면상혈관종에 대한 선형가속기를 이용한 고선량 정위 방사선수술의 임상경험)

  • Hong Semie;Chie Eui Kyu;Park Suk Won;Kim Il Han;Ha Sung Hwan;Park Charn Il
    • Radiation Oncology Journal
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    • v.21 no.2
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    • pp.107-111
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    • 2003
  • Purpose: To establish the role of stereoactic radiosurgery using a linear accelerator for the treatment of patients with cavernous angloma. Materials and Methods: Between February 1995 and May 1997, 11 patients with cavernous angioma were treated with stereotactic radiosurgery using a linear accelerator. Diagnoses were based on the magnetic resonance imaging in 8 patients, and the histological in 3. The vascular lesions were located on the brainstem (5 cases), cerebellum (2 cases) thalamus (1 case) and cerebrum (3 cases). The clinical presentation at onset included previous intracerebral hemorrhages (9 cases) and seizures (2 cases). All patients were treated with a a linac-based radiosurgery. The median dose of radiation delivered was 16 Gy ranging from 14 to 24 Gy, which was typically proscribed to the 80$\%$ isodose surface (range 50 $\~$ 80$\%$), corresponding to the periphery of the lesion with a single isocenter. Ten patients were followed-up. Results: The median follow-up was 49 months ranging from 8 to 73 months, during which time two patients developed an intracerebral hemorrhage, 1 at 8 months, with the other at 64 months post radiosurgery. One patient developed neurological deficit after radiosurgery, and two developed an edema on the T2 weighted images of the MRI surrounding the radiosurgical target. Conclusion: The use of stereotactic radiosurgery in the treatment of a cavernous angioma may be effective in the prevention of rebleedlng, and can be safely delivered. However, a longer follow-up period will be required.

A Patterns of Care Study of the Various Radiation Therapies for Prostate Cancer among Korean Radiation Oncologists in 2006 (Patterns of Care Study를 위한 2006년 한국 방사선종양학과 전문의들의 전립선암 방사선치료원칙 조사연구)

  • Kim, Jin-Hee;Kim, Jae-Sung;Ha, Sung-Whan;Shin, Seong-Soo;Park, Won;Cho, Jae-Ho;Suh, Chang-Ok;Oh, Young-Taek;Shin, Sei-Won;Kim, Jae-Chul;Jang, Ji-Young;Nam, Taek-Keun;Choi, Young-Min;Kim, Il-Han
    • Radiation Oncology Journal
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    • v.26 no.2
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    • pp.96-103
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    • 2008
  • Purpose: To conduct a nationwide academic hospital patterns of the practice status and principles of radiotherapy for prostate cancer. The survey will help develop the framework of a database of Korean in Patterns of Case Study. Materials and Methods: A questionnaire about radiation treatment status and principles was sent to radiation oncologists in charge of prostate cancer treatment at thirteen academic hospitals in Korea. The data was analyzed to find treatment principles among the radiation oncologists when treating prostate cancer. Results: The number of patients with prostate cancer and treated with radiation ranged from 60 to 150 per academic hospital in Seoul City and 10 to 15 outside of Seoul City in 2006. The primary diagnostic methods of prostate cancer included the ultrasound guided biopsy on 6 to 12 prostate sites(mean=9), followed by magnetic resonance imaging and a whole body bone scan. Internal and external immobilizations were used in 61.5% and 76.9%, respectively, with diverse radiation targets. Whole pelvis radiation therapy(dose ranging from 45.0 to 50.4 Gy) was performed in 76.9%, followed by the irradiation of seminal vesicles($54.0{\sim}73.8$ Gy) in 92.3%. The definitive radiotherapy doses were increased as a function of risk group, but the range of radiation doses was wide(60.0 to 78.5 Gy). Intensity modulated radiation therapy using doses greater than 70 Gy, were performed in 53.8% of academic hospitals. In addition, the simultaneous intra-factional boost(SIB) technique was used in three hospitals; however, the target volume and radiation dose were diverse. Radiation therapy to biochemical recurrence after a radical prostatectomy was performed in 84.6%; however, the radiation dose was variable and the radiation field ranged from whole pelvis to prostate bed. Conclusion: The results of this study suggest that a nationwide Korean Patterns of Care Study is necessary for the recommendation of radiation therapy guidelines of prostate cancer.

Patients with brain metastases the usefulness of contrast-enhanced FLAIR images after delay (뇌전이 환자의 조영 증강 후 지연 FLAIR 영상의 유용성)

  • Byun, Jae-Hu;Park, Myung-Hwan;Lee, Jin-Wan
    • Korean Journal of Digital Imaging in Medicine
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    • v.16 no.1
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    • pp.13-19
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    • 2014
  • Purpose: FLAIR image is beneficial for the diagnosis of various bran diseases including ischemic CVS, brain tumors and infections. However the border between the legion of brain metastasis and surrounding edema may not be clear. Therefore, this study aims to investigate the practical benefits of delayed imaging by comparing the image from a patient with brain metastasis before a contrast enhancement and the image 10 minutes after a contrast enhancement. Materials and methods: Of the 92 people who underwent MRI brain metastases in suspected patients 13 people in three patients there is no video to target the 37 people confirmed cases, and motion artifacts brain metastases in our hospital June-December 2013, 18 people measurement position except for the three incorrect patient (male: 11 people, female: 7 people, average age: 60 years) in the target, test equipment, 3.0T MR System (ACHIEVA Release, Philips, I was 8ChannelSENSE Head Coil use Best, and the Netherlands). TR 11000 ms, TE 125 ms, TI2800 ms, Slice Thickness 5 mm, gap 5 mm, is a Slice number 21, the parameters of the 3D FFE, T2 FLAIR variable that was used to test, TR 8.1 ms, TE 3.7 ms, Slice number 240 I set to. The experiment was conducted by acquiring the FLAIR prior to contrast enhancement (heretofore referred to as Pre FLAIR), and acquiring the 3D FFE CE five minutes after the contrast enhancement, and recomposing the images in an axial plane of S/T 3mm, G 0mm (heretofore referred to as MPR TRA CE). Using the FLAIR 10 minutes after the contrast enhancement (heretofore referred to as Post FLAIR) and Pi-View, a retrospective study was conducted. Using MRIcro on the image of a patient confirmed for his diagnosis, the images before and after the contrast media, as well as the CNR and SNR of the MPR TRA CE images of the lesion and the site absent of lesion were compared and analyzed using a one-way analysis of variance. Results: CNR for Pre FLAIR and Post FLAIR were 34.35 and 60.13, respectively, with MPR TRA CE at 23.77 showing no significant difference (p<0.050). Post-experiment analysis shows a difference between Pre FLAIR and Post FLAIR in terms of CNR (p<0.050), but no difference in CNR between Post FLAIR and MPR TRA CE (p>0.050), indicating that the contrast media had an effect only on Pre FLAIR and Post FLAIR. The SNR for the normal site Pre FLAIR was 106.43, and for the lesion site 140.79. Post FLAIR for the normal site was 107.79, and for the lesion site 167.91. MPR TRA CE for the normal site was 140.23 and for the lesion site 183.19, showing significant difference (p<0.050), and post-experiment analysis shows that there was a difference in SNR only on the lesion sites for Pre FLAIR and Post FLAIR (p<0.050). There was no difference in SNR between the normal site and lesion site for Post FLAIR and MPR TRA CE, indicating no effect from the contrast media (p>0.050). Conclusions: This experiment shows that Post FLAIR has a higher contrast than Pre FLAIR, and a higher SNR for lesions, It was not not statistically significant and MPR TRA CE but CNR came out high. Inspection of post-contrast which is used in a high magnetic field is frequently used images of 3D T1 but, since the signal of the contrast medium and the blood flow is included, this method can be diagnostic accuracy is reduced, it is believed that when used in combination with Post FLAIR, and that can provide video information added to the diagnosis of brain metastases.

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Study on Oxidation and Coercivity of Nd2Fe14B Compound Crystal (Nd2Fe14B 화합물 결정의 산화 및 보자력에 관한 연구)

  • Kwon, H.W.;Yu, J.H.
    • Journal of the Korean Magnetics Society
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    • v.22 no.3
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    • pp.85-90
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    • 2012
  • Oxidation of the $Nd_2Fe_{14}B$ compound crystal and its effect on the coercivity of the fine $Nd_2Fe_{14}B$ crystal particles were investigated. Oxidation kinetics of the $Nd_2Fe_{14}B$ compound crystal was investigated using an excessively grown $Nd_2Fe_{14}B$ grains in the $Nd_{15}Fe_{77}B_8$ alloy ingot. Oxidation of the $Nd_2Fe_{14}B$ compound crystal occurred by dissociation of the phase into multi-phase mixture of ${\alpha}$-Fe, $Fe_3B$, and Nd oxides. Oxidation rate of the $Nd_2Fe_{14}B$ compound crystal showed no dependence on the crystallographic direction. The oxidation reaction was modeled according to simple linear relationship. Activation energy for the oxidation of $Nd_2Fe_{14}B$ compound crystal was calculated to be approximately 26.8 kJ/mol. Fine $Nd_2Fe_{14}B$ crystal particles in near single domain size was prepared by ball milling of the HDDR-treated $Nd_{15}Fe_{77}B_8$ alloy, and these particles were used for investigating the effect of oxidation on the coercvity. The near single domain size $Nd_2Fe_{14}B$ crystal particles (${\fallingdotseq}0.3\;{\mu}m$) had high coercivity over 9 kOe. However, the coercivity was radically reduced as the temperature increased in air (<2 kOe at $200^{\circ}C$). This radical coercivity reduction was attributed to the soft magnetic phases, ${\alpha}$-Fe and $Fe_3B$, which were formed on the surface of the fine particles due to the oxidation.

Diagnostic Value of MRI in Schwannoma (신경초종 진단에 있어 자기공명영상촬영(MRI)의 진단적 가치)

  • Kim, Jeung Il;Kim, Um Ji;Moon, Tae Yong;Lee, In Sook;Song, You Seon;Choi, Kyung Un
    • The Journal of the Korean bone and joint tumor society
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    • v.20 no.2
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    • pp.60-65
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    • 2014
  • Purpose: To diagnose soft tissue tumor, such as lipoma and Schwannoma, magnetic resonance imaging (MRI) is sufficient in most cases. However, various characteristics are found in MRI images of Schwannoma, thus other type of tumors are often misdiagnosed as Schwannoma with MRI images. In this study, we evaluate the diagnostic value of specific MRI findings of Schwannoma. Materials and Methods: From January 2002 to May 2013, 104 patients who are suspected as Schwannoma rith MRI images are included in data, and the final diagnosis is confirmed with biopsy. Patients are divided into group 1 and group 2 who are confirmed as Schwannoma and other disease with biopsy, respectively. Results: 92 patients were diagnosed as Schwannoma (group 1) and 12 patients were diagnosed as other disease (group 2). We investigate the diagnostic value of specific MRI findings of Schwannoma. 41 patients of group 1 (45%) and 0 patients of group 2 (0%) showed target sign, 47 patients of group 1 (51%) and 2 patients of group 2 (17%) showed fascicular sign, 44 patients of group 1 (48%) and 5 patients of group 2 (42%) showed fat split sign, 28 patients of group 1 (30%) and 1 patients of group 2(9%) showed nerve entering and exiting sign, and 8 patients of group 1 (9%) and 6 patients of group 2 (50%) showed none of four specific findings on their MRI images. 52 patients of group 1 (57%) and 5 patients of group 2 (42%) have tumors on the pathway of nerve. Target sign could be considered as the best diagnostic value of the sign we investigate (p<0.05). Conclusion: Although specific MRI findings have powerful diagnostic value, patients are often misdiagnosed as Schwannoma with MRI findings. Therefore, if patients who are suspected as Schwannoma based on MRI findings have no target sign on their MRI images, we should consider the possibility of other disease.

Verification of Indicator Rotation Correction Function of a Treatment Planning Program for Stereotactic Radiosurgery (방사선수술치료계획 프로그램의 지시자 회전 오차 교정 기능 점검)

  • Chung, Hyun-Tai;Lee, Re-Na
    • Journal of Radiation Protection and Research
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    • v.33 no.2
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    • pp.47-51
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    • 2008
  • Objective: This study analyzed errors due to rotation or tilt of the magnetic resonance (MR) imaging indicator during image acquisition for a stereotactic radiosurgery. The error correction procedure of a commercially available stereotactic neurosurgery treatment planning program has been verified. Materials and Methods: Software virtual phantoms were built with stereotactic images generated by a commercial programming language, Interactive Data Language (version 5.5). The thickness of an image slice was 0.5 mm, pixel size was $0.5{\times}0.5mm$, field of view was 256 mm, and image resolution was $512{\times}512$. The images were generated under the DICOM 3.0 standard in order to be used with Leksell GammaPlan$^{(R)}$. For the verification of the rotation error correction function of Leksell GammaPlan$^{(R)}$, 45 measurement points were arranged in five axial planes. On each axial plane, there were nine measurement points along a square of length 100 mm. The center of the square was located on the z-axis and a measurement point was on the z-axis, too. Five axial planes were placed at z=-50.0, -30.0, 0.0, 30.0, 50.0 mm, respectively. The virtual phantom was rotated by $3^{\circ}$ around one of x, y, and z-axis. It was also rotated by $3^{\circ}$ around two axes of x, y, and z-axis, and rotated by $3^{\circ}$ along all three axes. The errors in the position of rotated measurement points were measured with Leksell GammaPlan$^{(R)}$ and the correction function was verified. Results: The image registration errors of the virtual phantom images was $0.1{\pm}0.1mm$ and it was within the requirement of stereotactic images. The maximum theoretical errors in position of measurement points were 2.6 mm for a rotation around one axis, 3.7 mm for a rotation around two axes, and 4.5 mm for a rotation around three axes. The measured errors in position was $0.1{\pm}0.1mm$ for a rotation around single axis, $0.2{\pm}0.2mm$ for double and triple axes. These small errors verified that the rotation error correction function of Leksell GammaPlan$^{(R)}$ is working fine. Conclusion: A virtual phantom was built to verify software functions of stereotactic neurosurgery treatment planning program. The error correction function of a commercial treatment planning program worked within nominal error range. The virtual phantom of this study can be applied in many other fields to verify various functions of treatment planning programs.

Differentiation of Medial or Lateral Temporal Lobe Epilepsy by F-18-Fluorodeoxyglucose Positron Emission Tomography: Comparative Study with Magnetic Resonance Imaging in 113 Surgically and Pathologically Proven Patients (F-18-Fluorodeoxyglucose 양전자단층촬영을 이용한 내외측 측두엽간질의 감별: 수술과 병리 소견으로 확진한 113예에서 자기공명영상과 비교 분석)

  • Lee, Dong-Soo;Lee, Sang-Kun;Chang, Ki-Hyun;Chung, Chun-Kee;Choi, Ki-Young;Chung, June-Key;Lee, Myung-Chul
    • The Korean Journal of Nuclear Medicine
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    • v.33 no.2
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    • pp.111-119
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    • 1999
  • Purpose: As mesial temporal lobe epilepsy (TLE) shows hypometabolism of medial and lateral temporal lobe, we investigated whether symmetric uptake of F-18-FDG in medial temporal lobes can differentiate mesial from lateral TLE. Materials and Methods: In 113 patients (83 mesial TLE, 30 lateral TLE) who underwent anterior temporal lobectomy and/or corticectomy with good surgical outcome, we performed F-18-FDG PET and compared F-18-FDG uptake of medial and lateral temporal lobes. All the patients with mesial TLE had hippocampal sclerosis except one congenital abnormal hippocampus. Patients with lateral TLE revealed cerebromalacia, microdysgenesis, arteriovenous malformation, old contusion, and cortical dysplasia. Results: Sensitivity of F-18-FDG PET and MR for mesial TLE was 84% (70/83) and 73% (61/83), respectively. Sensitivity of F-18-FDG PET and MR for lateral TLE was 90% (27/30) and 66% (20/30), respectively. Twelve patients were normal on F-18-FDG PET. 101 patients had hypometabotism of lateral temporal lobe. Among 88 patients who showed hypometabolism of medial temporal lobe as well as lateral temporal lobe, 70 were mesial TLE patients and 18 were lateral TLE on pathologic examination. Positive predictive value of medial temporal hypometabolism for mesial TLE was 80%. Among 13 patients who showed hypometabolism of only lateral temporal lobe, 4 were mesial TLE and 9 were lateral TLE. Positive predictive value of hypometabolism of lateral temporal lobe for the diagnosis of lateral TLE was 69% (9/13). Normal MR findings stood against medial TLE, whose negative predictive value was 66%. Conclusion: Lateral temporal lobe epilepsy should be suspected when there is decreased F-18-FDG uptake in lateral temporal lobe with normal uptake in medial temporal lobe.

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Outcome of Arthroscopic Suture Bridge Technique for Rotator Cuff Tear: Short Term Clinical Outcome In Full-thickness Tear With Fatty Degeneration Less Than Moderate Degree (회전근 개 파열에 대한 관절경적 교량형 봉합술의 결과: 지방 변성이 중등도 이하인 전층 파열에 대한 단기 추시 임상적 결과)

  • Cheon, Sang-Jin;Hur, Joon-Oh;Suh, Jeung-Tak;Yoo, Chong-Il
    • Clinics in Shoulder and Elbow
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    • v.12 no.2
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    • pp.180-188
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    • 2009
  • Purpose: We evaluate the short-term clinical outcome of arthroscopic rotator cuff tendon repair with suture-bridge technique in patients with full thickness rotator cuff tear. Materials and Methods: 29 (male:17, female:12) consecutive shoulders treated with this index procedure and early rehabilitation were enrolled. Mean age was 56.4 years (range, 34~73 years) and mean follow-up period was 13 months (range, 12-15 months). Clinical outcomes were evaluated by using the University of California Los Angeles (UCLA) score, the Korean Shoulder Scoring System (KSS) and Visual Analogue Scale (VAS). Postoperative cuff integrity was evaluated through magnetic resonance imaging (MRI) and categorized by Sugaya classification. Results: Postoperative UCLA scores improved from 16.4 to 31.6 (p< 0.05) and KSS scores showed 88 at 6 months and 92 at last follow up. Preoperative VAS score was 8.6, which was decreased to 2.1 at 3 months and 1.4 at 6 months postoperatively. 28 patients (96.5%) had increase in range of motion. The follow up MRI was taken in 15 shoulders and the cuff integrity was type I in 6 cases, type II in 7, type III in 1 and type V in 1 by Sugaya classification. Conclusion: Arthroscopic suture-bridge technique resulted in good or excellent clinical outcome in 96.5% of the cases, so we think this technique is one of the reliable procedure for full-thicknes rotator cuff tear.