• Title/Summary/Keyword: Magnetic Materials

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Correlation Analysis between the Factors Associated with Osteoporosis and the Fat Infiltration Rate of the Multifidus and Erector Spinae Muscles in Osteoporotic Vertebral Compression Fracture Patients (골다공증성 척추 압박 골절 환자에서 다열근과 척추기립근의 지방 침투율과 골다공증 관련 인자의 상관 관계 분석)

  • Jun, Deuk Soo;Baik, Jong-Min;Choi, Ji Uk
    • Journal of the Korean Orthopaedic Association
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    • v.55 no.4
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    • pp.318-323
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    • 2020
  • Purpose: To examine the relationship between total fat infiltration (TFI) rate, which quantifies the reduction of muscles around the spine and is an important factor for sarcopenia, and the factors affecting osteoporotic vertebral compression fracture. Materials and Methods: Patients treated for osteoporotic compression fractures of the lumber spine from January 2012 to December 2016 were analyzed retrospectively. Among them, this study included ninety-eight patients who were 1) diagnosed with osteoporosis with a bone mineral density (BMD) T score of less than 2.5 g/cm2, 2) received vertebroplasty or kyphoplasty for lumbar fractures, 3) involved one segment of the lumbar spine, and 4) were followed-up for more than one year. The TFI rate confirmed by analyzing magnetic resonance imagings with the Image J program was studied. Based on this, the relationship between the TFI of the multifidus and erector spinae muscles and the factors of osteoporosis were analyzed. Results: The mean TFI of the multifidus and erector spinae was 14.66±10.16. The spine BMD showed a positive correlation with the hip BMD, but a negative correlation with the TFI. A positive correlation was observed between the hip BMD and body mass index. In addition, vitamin D was positively correlated with both the hip and spine BMD but negatively correlated with the TFI rate. Conclusion: Muscle growth helps treat osteoporosis, and can prevent fractures that occur frequently in osteoporosis patients. Increasing the vitamin intake can also slow the progression of muscle atrophy.

Prevalence of Tarsal Coalition in the Korean Population: A Single Institution-Based Study (한국인의 족근골 유합의 유병률: 병원 내원 환자에 대한 연구)

  • Kim, Tae Yong;Yoon, So Hee;Ko, Jung Hoon;Lee, Tae Ho;Yi, Seung Rim
    • Journal of the Korean Orthopaedic Association
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    • v.55 no.4
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    • pp.324-330
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    • 2020
  • Purpose: Korean studies on the prevalence of a tarsal coalition are quite rare, and there are very few reports on the prevalence of multiple tarsal coalitions among adults in the foreign literature. Therefore, this study examined the characteristics and prevalence of tarsal coalition in the Korean population based on imaging tests. Materials and Methods: The prevalence of tarsal coalition and its anatomical location and histological classification were reviewed retrospectively among 4,711 patients (4,454 males and 257 females) with an ankle sprain or ankle fracture who underwent foot and ankle computed tomography and magnetic resonance imaging between March 2009 and February 2019 at the authors' institution. Results: Over a period of 10 years, 78 patients (1.7%) had a tarsal coalition, among whom 53 patients (67.9%) had an isolated tarsal coalition and 25 patients (32.1%) had multiple tarsal coalitions. Regarding the anatomical location, a talocalcaneal coalition was the most common type in both isolated (31 patients, 37 cases [62.7%]) and multiple (22 patients, 23 cases [45.1%]) tarsal coalitions. In the isolated coalition group, the second-most common type was calcaneonavicular coalition (10 patients, 16.9%), followed by naviculocuneiform (nine patients, 15.3%) and cuboidonavicular coalitions (three patients, 5.1%). In the multiple coalition group, the second-most common coalition type was calcaneonavicular coalition (14 patients, 14 cases [27.5%]), followed by talonavicular coalition (six patients, six cases [11.8%]). From a total of 60 cases of talocalcaneal coalition, 24 cases (40.0%) were in the posterior facet, 18 cases (30.0%) in the middle facet, and four cases (6.7%) in the anterior facet. Regarding the histological classification, cartilaginous coalition was the most common in both single (32 patients, 35 cases [59.3%]) and multiple (20 patients, 37 cases [72.5%]) coalition groups. Conclusion: The present study found that talocalcaneal coalition was the most common type of tarsal coalition. In contrast to previous reports that a talocalcaneal coalition generally occurs in the middle facet, it was usually observed in the posterior facet in the present study. In addition, although multiple tarsal coalitions have been reported to be quite rare, this study confirmed that they are not rare and can occur in a range of patterns.

Arthroscopic Full-Thickness Rotator Cuff Repair in Elderly Patients (고령 환자의 관절경적 회전근 개 봉합술의 결과)

  • Cheon, Sang Jin;Lee, Dong Ho;Park, Yong Geon;Son, Seung Min
    • Journal of the Korean Orthopaedic Association
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    • v.55 no.1
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    • pp.38-45
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    • 2020
  • Purpose: To examine the clinical and structural outcomes of an at least two-year follow-up of arthroscopic full-thickness rotator cuff repairs with a single-row or suture-bridge technique in patients more than 65 years of age. Materials and Methods: Patients diagnosed with a full-thickness rotator cuff tear who were more than 65 years of age, underwent arthroscopic rotator cuff repair after at least six months of conservative treatment, agreed to take a follow-up magnetic resonance imaging (MRI) six months postoperatively, and visited outpatient for at least two years were enrolled in this study. Clinical evaluations were done using The University of California Los Angeles score, Constant Shoulder Score, and visual analogue scale evaluated two years after the surgery. The structural integrity was analyzed using follow-up MRI. During surgery, a suture-bridge technique was used if the rotator cuff tendon could cover half of the footprint under constant tension. Otherwise, single-row repair was performed. Results: The samples were 158 cases, consisting of 93 single-repairs and 65 suture-bridge repairs. A preoperative comparison of the age distribution, fatty degeneration of supraspinatus and infraspinatus muscle, medial retraction of torn cuff tendon, and tear size between the two groups were not significant. The clinical scores were improved significantly in all cases. The distribution of the structural integrity by Sugaya classification were 49 cases in type 1 (31.0%), 62 cases in type 2 (39.2%), 30 cases in type 3 (19.0%), 11 cases in type 4 (7.0%), and six cases in type 5 (3.8%). The re-tear rate of the single-row group was 9.7% (nine out of 93 cases) and 12.3% (eight out of 65 cases) for the suture-bridge group. Conclusion: Satisfactory clinical and radiological outcomes were achieved after arthroscopic full-thickness rotator cuff repair in patients more than 65 years of age. Both single-row and suture-bridge techniques would be beneficial for the elderly.

Outcome of Type 3 Talar Neck Fractures by Means of Medial Malleolar Osteotomy and Large Distractor (족관절 내과 절골술 및 대형신연기를 이용한 제3형 거골 경부 골절의 치료 결과)

  • Park, Sung Hae;Lee, Jun Young;Lee, Jung Woo
    • Journal of the Korean Orthopaedic Association
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    • v.54 no.1
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    • pp.45-51
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    • 2019
  • Purpose: The clinical and radiological results of patients with type 3 talar neck fractures treated with the anteromedial approach using medial malleolar osteotomy and large distractor were analyzed retrospectively. Materials and Methods: From March 2009 to August 2016, 12 patients with a type 3 talar neck fracture, who underwent the anteromedial approach using a medial malleolar osteotomy and large distractor and who could be followed-up for more than 12 months after the operation, were examined. The patients were examined for the presence of Hawkins signs by anteroposterior and lateral radiographs and osteonecrosis by magnetic resonance imaging (MRI) on the postoperative 3 months. Subsequently, every 3 months, radiographic union was assessed by a simple radiograph and clinical symptoms. Twelve months postoperatively, posttraumatic arthritis was assessed and the American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot score was analyzed. Results: In 7 cases, osteonecrosis was found on MRI performed 3 months after surgery. On the other hand, at the 12 months follow-up, all of them obtained AOFAS scores of 83.86±4.53 without surgical treatment. Radiographic union was achieved in all cases. The mean union period was 5.3 months. In 10 cases, traumatic arthritis was found after the radiographical and clinical evaluation. In addition, all of them could carry on everyday life by conservative treatment. The AOFAS ankle-hindfoot score was measured to be 85.17 on average. Other complications included superficial wound infection in 2 cases. Conclusion: An anteromedial approach using a medial malleolar osteotomy and a large distractor in the surgical treatment of patients with type 3 talar neck fractures can achieve anatomical reduction of the displaced fragment without a lateral dissection. This is considered to be another good surgical option.

The Clinical Outcome of Dedifferentiated Chondrosarcoma (역분화 연골육종의 임상 결과)

  • Kong, Chang-Bae;Lee, Seung Yong;Song, Won-Seok;Cho, Wan-Hyeong;Koh, Jae-Soo;Jeon, Dae-Geun
    • Journal of the Korean Orthopaedic Association
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    • v.54 no.2
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    • pp.164-171
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    • 2019
  • Purpose: A dedifferentiated chondrosarcoma is a rare lethal tumor characterized by a low grade chondrosarcoma juxtaposed with a high grade dedifferentiated sarcoma, such as osteosarcoma, fibrosarcoma. The aim of our study was to document the clinical manifestation and oncologic outcomes of a dedifferentiated chondrosarcoma. Materials and Methods: This study identified 11 patients who were diagnosed and treated for dedifferentiated chondrosarcoma between January 2007 and December 2016. The identified cohort was then reviewed regarding age, sex, symptom onset, tumor location, magnetic resonance imagings (MRIs), surgical margin, and pathologic diagnosis. The time to local recurrence and/or metastasis, follow-up duration, and the patients' final status were analyzed. Results: The patients were comprised of 7 males and 4 females with a mean age of 54 years (range, 33-80 years). The location of the tumor was in the femur in 6 cases, pelvis in 4 cases, and metatarsal in 1 case. The average tumor diameter was 12.7 cm (range, 6.0-26.1 cm). At the time of diagnosis, 2 patients showed pathologic fracture; 1 patient was Enecking stage IIA, 9 patients were stage IIB, and 1 patient was stage III. Eight patients were classified as a primary dedifferentiated chondrosarcoma and 3 patients were secondary. One of the primary lesions was misinterpreted initially as a low grade chondroid lesion by MRI and underwent curettage. Local recurrence occurred in 8 cases and distant metastasis occurred in 10 cases with a mean duration of 8 months (range, 2-23 months) and 7 months (range, 1-32 months), respectively. The three-year overall survival of patients with dedifferentiated chondrosarcoma was 18%, and 10 patients died due to disease progression. Conclusion: Dedifferentiated chondrosarcoma developed lung metastases in the early period of the clinical courses and the prognosis was dismal.

Suggestions of Stone Materials for Restoration of Gwanghwamun Woldae in Seoul Based on Lithological Study (암석학적 연구를 통한 서울 광화문 월대 복원용 석재 제안)

  • Myeong Seong Lee;Yu Bin Ahn;Se Rin Park;Myoungju Choie;Jiyoung Kim
    • Economic and Environmental Geology
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    • v.56 no.6
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    • pp.647-659
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    • 2023
  • This study is to analyze the lithological similarities between railing stones of Gwanghwamun Woldae and stone blocks stored in Donggureung Royal Tombs, Guri, to interpret the provenance of the stones, and to suggest the most suitable quarry for a new stones supply among the rocks in the Seoul-Pocheon area in order to select stones for the restoration of the Gwanghwamun Woldae. The railing stones in Donggureung are medium to coarse-grained pink biotite granite, and their lithological characteristics, magnetic susceptibility(Average 5.20 ×10-3 SI unit), and gamma spectrometer data(K 5.00~6.38%, U 4.92~8.56 ppm, Th 27.60~36.44 ppm) show similarities with the remaining railing stones in Gwanghwamun Woldae(Average 5.38). Therefore, the railing stones in Donggureung can be reused for the restoration of Gwanghwamun Woldae. They have similar lithological and geochemical charateristics to the pink biotite granite found the Suraksan Mt. and Buramsan Mr. areas in Seoul, suggesting that these areas are the source of the stone. However, since the Suraksan Mt. and Buramsan Mt. areas are currently unavailable for quarrying, lithological and geochemical analyses on granite from the Yangju and Pocheon areas are conducted to determine the suitability of the new stone for restoration. As a result, a pink biotite granite similar to the Woldae stones was identified in the Pocheon area, and it is suggested that the stones similar in grain size and colour to the railing stones of Gwanghwamun Woldae should be selected and used for the restoration of Gwanghwamun Woldae.

The synthesis of dextran from rice hydrolysates using Gluconobacter oxydans KACC 19357 bioconversion (Gluconobacter oxydans 생물전환을 통한 쌀 가수분해물 유래 dextran 합성)

  • Seung-Min Baek;Hyun Ji Lee;Legesse Shiferaw Chewaka;Chan Soon Park;Bo-Ram Park
    • Food Science and Preservation
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    • v.31 no.1
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    • pp.149-160
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    • 2024
  • Dextran is a glucose homo-polysaccharide with a predominantly α-1,6 glycosidic linkage of microbial source and is known to be produced primarily by lactic acid bacteria. However, it can also be obtained through the dextran dextrinase of acetic acid bacteria (Gluconobacter oxydans). The dextrin-based dextran was obtained from rice starch using G. oxydans fermentation of rice hydrolysate, and its properties were studied. Both dextrin- and rice hydrolysate-added media maintained the OD value of 6 after 20 h of incubation with acetic acid bacteria, and the gel permeation chromatography (GPC) analysis of the supernatant after 72 h of incubation confirmed that a polymeric material with DP of 480 and 405, which was different from the composition of the substrate in the medium, was produced. The glucose linkage pattern of the polysaccharide was confirmed using the proton nuclear magnetic resonance (1H-NMR) and the increased α-1,4:α-1,6 bond ratio from 0.23 and 0.13 to 1:2.37 and 1:4.4, respectively, indicating that the main bonds were converted to α-1,6 bonds. The treatment of dextrin with a rat-derived alpha-glucosidase digestive enzyme resulted in a slow release of glucose, suggesting that rice hydrolysate can be converted to dextran using acetic acid bacteria with glycosyltransferase activity to produce high-value bio-materials with slowly digestible properties.

To Assess Whether Lee's Grading System for Central Lumbar Spinal Stenosis Can Be Used as a Decision-Making Tool for Surgical Treatment (요추 중심 신경관 협착에 있어서 Lee's Grade를 통한 MRI 평가방법이 수술적 치료 결정에 유용한가에 대한 연구)

  • Do Yeon Ahn;Hee Jin Park;Jung Woo Yi;Ji Na Kim
    • Journal of the Korean Society of Radiology
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    • v.83 no.1
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    • pp.102-111
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    • 2022
  • Purpose To evaluate the correlation between Lee's grades and surgical intervention for central lumbar spinal stenosis (CLSS) and to assess whether this grading system can be used as a decision-making tool for the surgical treatment of this condition. Materials and Methods This retrospective study included 290 patients (M:F = 156:134; mean age, 46 ± 16 years). Radiologists assessed the presence and grade of CLSS at the stenosis point according to Lee's grading system, in which CLSS is classified into four grades according to the shape of the cauda equina. Correlation coefficients (rs) between Lee's grades and the operation were calculated with Spearman rank correlation. Results Among the operated patients, grade 2 was the most commonly assigned grade (50%-58%), grade 3 was less common (35%), and grade 0 was the least common (2%-3%). Among the non-operated patients, grade 1 was the most common (63%-65%), grade 0 was less common (15%-16%), and grade 3 was the least common (8%). The distribution of grades differed between the operated and non-operated groups (p < 0.001). Less than 25% of patients who underwent surgery were assigned grades 0 and 1, and more than 88% were assigned grades 2 and 3. A moderate correlation was found between the grade and surgical intervention (rs = 0.632 and rs = 0.583). Conclusion Lee's grade was moderately correlated with surgical intervention. Lee's grading system can be a decision-making tool for the surgical treatment of CLSS.

Comparison of Computed Diffusion-Weighted Imaging b2000 and Acquired Diffusion-Weighted Imaging b2000 for Detection of Prostate Cancer (전립선암 발견을 위한 계산형 확산강조영상 b2000과 실제 획득한 b2000 영상의 비교)

  • Yeon Jung Kim;Seung Ho Kim;Tae Wook Baek;Hyungin Park;Yun-jung Lim;Hyun Kyung Jung;Joo Yeon Kim
    • Journal of the Korean Society of Radiology
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    • v.83 no.5
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    • pp.1059-1070
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    • 2022
  • Purpose To compare the sensitivity of tumor detection and inter-observer agreement between acquired diffusion-weighted imaging (aDWI) b2000 and computed DWI (cDWI) b2000 in patients with prostate cancer (PCa). Materials and Methods Eighty-eight patients diagnosed with PCa by radical prostatectomy and having undergone pre-operative 3 Tesla-MRI, including DWI (b, 0, 100, 1000, 2000 s/mm2), were included in the study. cDWI b2000 was obtained from aDWI b0, b100, and b1000. Two independent reviewers performed a review of the aDWI b2000 and cDWI b2000 images in random order at 4-week intervals. A region of interest was drawn for the largest tumor on each dataset, and a Prostate Imaging-Reporting and Data System (PI-RADS) score based on PI-RADS v2.1 was recorded. Histologic topographic maps served as the reference standard. Results The study population's Gleason scores were 6 (n = 16), 7 (n = 53), 8 (n = 9), and 9 (n = 10). According to the reviewers, the sensitivities of cDWI b2000 and aDWI b2000 showed no significant differences (for reviewer 1, both 94% [83/88]; for reviewer 2, both 90% [79/88]; p = 1.000, respectively). The kappa values of cDWI b2000 and aDWI b2000 for the PI-RADS score were 0.422 (95% confidence interval [CI], 0.240-0.603) and 0.495 (95% CI, 0.308-0.683), respectively. Conclusion cDWI b2000 showed comparable sensitivity with aDWI b2000, in addition to sustained moderate inter-observer agreement, in the detection of PCa.

Structural and Resting-State Brain Alterations in Trauma-Exposed Firefighters: Preliminary Results (외상에 노출된 소방관들의 뇌 구조 및 휴식기 뇌기능 변화: 예비 결과)

  • Yae Won Park;Suhnyoung Jun;Juwhan Noh;Seok Jong Chung;Sanghoon Han;Phil Hyu Lee;Changsoo Kim;Seung-Koo Lee
    • Journal of the Korean Society of Radiology
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    • v.81 no.3
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    • pp.676-687
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    • 2020
  • Purpose To analyze the altered brain regions and intrinsic brain activity patterns in trauma-exposed firefighters without posttraumatic stress disorder (PTSD). Materials and Methods Resting-state functional MRI (rsfMRI) was performed for all subjects. Thirty-one firefighters over 40 years of age without PTSD (31 men; mean age, 49.8 ± 4.7 years) were included. Twenty-six non-traumatized healthy controls (HCs) (26 men; mean age, 65.3 ± 7.84 years) were also included. Voxel-based morphometry was performed to investigate focal differences in the brain anatomy. Seed-based functional connectivity analysis was performed to investigate differences in spontaneous brain characteristics. Results The mean z-scores of the Seoul Verbal Learning Test for immediate and delayed recall, Controlled Oral Word Association Test (COWAT) score for animals, and COWAT phonemic fluency were significantly lower in the firefighter group than in the HCs, indicating decreased neurocognitive function. Compared to HCs, firefighters showed reduced gray matter volume in the left superior parietal gyrus and left inferior temporal gyrus. Further, in contrast to HCs, firefighters showed alterations in rsfMRI values in multiple regions, including the fusiform gyrus and cerebellum. Conclusion Structural and resting-state functional abnormalities in the brain may be useful imaging biomarkers for identifying alterations in trauma-exposed firefighters without PTSD.