• Korean Journal of Radiology
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• 제19권6호
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• pp.1161-1171
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• 2018

Objective: The aim of this study was to investigate diffusion tensor (DT) imaging-derived properties of benign oligemia, true "at risk" penumbra (TP), and the infarct core (IC) during the first 3 hours of stroke onset. Materials and Methods: The study was approved by the local animal care and use committee. DT imaging data were obtained from 14 rats after permanent middle cerebral artery occlusion (pMCAO) using a 7T magnetic resonance scanner (Bruker) in room air. Relative cerebral blood flow and apparent diffusion coefficient (ADC) maps were generated to define oligemia, TP, IC, and normal tissue (NT) every 30 minutes up to 3 hours. Relative fractional anisotropy (rFA), pure anisotropy (rq), diffusion magnitude (rL), ADC (rADC), axial diffusivity (rAD), and radial diffusivity (rRD) values were derived by comparison with the contralateral normal brain. Results: The mean volume of oligemia was $24.7{\pm}14.1mm^3$, that of TP was $81.3{\pm}62.6mm^3$, and that of IC was $123.0{\pm}85.2mm^3$ at 30 minutes after pMCAO. rFA showed an initial paradoxical 10% increase in IC and TP, and declined afterward. The rq, rL, rADC, rAD, and rRD showed an initial discrepant decrease in IC (from -24% to -36%) as compared with TP (from -7% to -13%). Significant differences (p < 0.05) in metrics, except rFA, were found between tissue subtypes in the first 2.5 hours. The rq demonstrated the best overall performance in discriminating TP from IC (accuracy = 92.6%, area under curve = 0.93) and the optimal cutoff value was -33.90%. The metric values for oligemia and NT remained similar at all time points. Conclusion: Benign oligemia is small and remains microstructurally normal under pMCAO. TP and IC show a distinct evolution of DT-derived properties within the first 3 hours of stroke onset, and are thus potentially useful in predicting the fate of ischemic brain.

• 대한족부족관절학회지
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• 제23권2호
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• pp.58-66
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• 2019

Purpose: To evaluate the efficacy of antibiotic-loaded cement spacers (ALCSs) for the treatment of diabetic foot infections with osteomyelitis as a salvage procedure and to analyze the risk factors of treatment failure. Materials and Methods: This study reviewed retrospectively 39 cases of diabetic foot infections with osteomyelitis who underwent surgical treatment from 2009 to 2017. The mean age and follow-up period were $62{\pm}13years$ and $19.2{\pm}23.3months$, respectively. Wounds were graded using the Wagner and Strauss classification. X-ray, magnetic resonance imaging (or bone scan) and deep tissue cultures were taken preoperatively to diagnose osteomyelitis. The ankle-brachial index, toe-brachial index (TBI), and current perception threshold were checked. Lower extremity angiography was performed and if necessary, percutaneous transluminal angioplasty was conducted preoperatively. As a surgical treatment, meticulous debridement, bone curettage, and ALCS placement were employed in all cases. Between six and eight weeks after surgery, ALCS removal and autogenous iliac bone graft were performed. The treatment was considered successful if the wounds had healed completely within three months without signs of infection and no additional amputation within six months. Results: The treatment success rate was 82.1% (n=32); 12.8% (n=5) required additional amputation and 5.1% (n=2) showed delayed wound healing. Bacterial growth was confirmed in 82.1% (n=32) with methicillin-resistant Staphylococcus aureus being the most commonly identified strain (23.1%, n=9). The lesions were divided anatomically into four groups; the largest number was the toes: (1) toes (41.0%, n=16), (2) metatarsals (35.9%, n=14), (3) midfoot (5.1%, n=2), and (4) hindfoot (17.9%, n=7). A significant difference in the Strauss wound score and TBI was observed between the treatment success group and failure group. Conclusion: The insertion of ALCSs can be a useful treatment option in diabetic foot infections with osteomyelitis. Low scores in the Strauss classification and low TBI are risk factors of treatment failure.

• 대한영상의학회지
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• 제79권6호
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• pp.340-347
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• 2018

목적: 가도세틱산-조영증강 MRI에서 간세포암 피막 발견에 대한 영상차감기법의 진단적 가치를 알아보고자 하였다. 대상과 방법: 2015년 5월부터 2017년 2월까지 가도세틱산-조영증강 MRI를 시행 받고 수술을 시행한 hepatocellular carcinoma (이하 HCC) 고위험군 108명을 대상으로 하였다. 차감영상의 질 및 간문맥기와 이행기의 일반영상과 차감영상에서 피막 여부에 대해 평가하였고, 차감영상에서의 피막 여부가 Liver Imaging Reporting and Data System에 따른 간세포암 진단에 미치는 영향을 평가하였다. 결과: 수술 전 경동맥화학색전술을 시행 받았거나 차감영상의 질이 불만족스러운 34명의 환자를 제외한 74명의 환자에서 82개의 간 병변(간세포암 73개, 그 외 악성종양 5개, 양성종양 4개)에 대해 분석하였다. 피막의 발견에 대한 차감영상의 민감도, 정확도, 그리고 곡선하면적은 일반영상과 비교하여 통계적으로 유의하게 높았고(각 95.4%, 89.0%, 0.80; p < 0.001), 특이도는 동일하였다(64.7%). HCC의 진단에 대해서도 차감영상이 일반영상과 비교하여 민감도, 정확도, 그리고 곡선하면적이 통계적으로 유의하게 높았으며(각 82.2%, 79.3%, 0.69; p = 0.011), 특이도는 동일하였다(55.6%). 결론: 가도세틱산-조영증강 MRI에서 간문맥기 또는 이행기로부터의 차감영상은 간세포암 피막의 발견에 도움이 된다.

• Clinics in Shoulder and Elbow
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• 제24권1호
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• pp.21-26
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• 2021

Background: To evaluate the demographics, clinical and radiographic features of calcific tendinitis of the shoulder in the Korean population, specifically focusing on the incidence of coexisting rotator cuff tear. Methods: Between October 2014 and January 2015, we performed a prospective multicenter study with 506 patients from 11 training hospitals in Korea. We collected data of demographics and radiographic analysis based on simple radiographs, clinical assessments based on visual analog scale (VAS) and the American Shoulder Elbow Surgeons (ASES) score, and treatment modalities that are used currently. We also evaluated coexisting rotator cuff tear by ultrasonography (US) or magnetic resonance imaging (MRI) images. Results: There were 402 female patients (79%) with mean age of 55 years (range, 31-87 years). Mean duration of symptoms was 16 months. Mean size of calcific materials was 11.4 mm (range, 0-35 mm). Mean value of VAS and ASES scores were 6.5 (range, 1-10) and 47 (range, 8-95), respectively. Of 383 patients (76%), 59 (15%) had rotator cuff tear including 15 full-thickness tears on US or MRI. Patients with rotator cuff tears were significantly associated with older age, recurrent symptoms, menstrual disorders in females, and having undergone calcification removal surgery and rotator cuff repair (all p<0.05). Conclusions: This study reported demographic, radiographic, and clinical features of calcific tendinitis of the shoulder in Korean population, which were not different from those of Western population. Coexisting rotator cuff tear was found with 15% incidence in this large series, suggesting that further radiographic study to evaluate rotator cuff tear might be needed in some calcific tendinitis patients of older age and presenting with recurrent symptoms.

• 대한족부족관절학회지
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• 제26권2호
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• pp.95-102
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• 2022

Purpose: This study was based on the Korean Foot and Ankle Society (KFAS) member survey and aimed to report the current trends in the management of syndesmotic injuries over the last few decades. Materials and Methods: A web-based questionnaire containing 36 questions was sent to all KFAS members in September 2021. The questions were mainly related to the preferred techniques and clinical experiences in the treatment of patients with syndesmotic injuries. Answers with a prevalence ≥50% of respondents were considered a tendency. Results: Seventy-six (13.8%) of the 550 members responded to the survey. The results showed that the most preferred method to diagnose a syndesmotic injury was magnetic resonance imaging (MRI). Intraoperatively, the external rotation stress test and the Cotton test were most frequently used to confirm syndesmotic diastasis. The reduction was usually done by a reduction clamp. One 3.5-mm screw was used most frequently over three cortices at 2~4 cm above the ankle joint. The preferred ankle position during fixation was 0° dorsiflexion. Removal of the syndesmotic screw was routinely done by most surgeons, mainly because of the limitation of movement and risk of screw breakage. Factors that affect suture button selection included non-rigid fixation which enables adequate fixation, early weight-bearing, and an infrequent need to remove the hardware. Inadequate reduction was considered the main factor that affects poor prognosis. Conclusion: This study proposes updated information about the current trends in the management of syndesmotic injuries in Korea. Consensuses in both the diagnostic and therapeutic approach to patients with syndesmotic injury were identified in this survey study. This study may raise the awareness of the various possible approaches toward the injury and should be used to further establish a standard protocol for the management of syndesmotic injuries.

• 대한족부족관절학회지
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• 제25권4호
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• pp.149-156
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• 2021

Purpose: Given the lack of definite evidence-based guidelines in clinical practice, there may be a wide variation in treatment protocols for osteochondral lesions of the talus (OLT). Based on the Korean Foot and Ankle Society (KFAS) member survey, this study aimed to report the current trends in the management of OLT. Materials and Methods: A web-based questionnaire containing 30 questions was sent to all KFAS members in September 2021. The questions were mainly related to clinical experience and preferences in diagnosis, conservative, and surgical treatments for patients with OLT. Answers with a prevalence of ≥50% of respondents were considered a tendency. Results: Sixty-two (11.3%) of the 550 surgeons queried responded to the survey. The responses to 9 (30.0%) of the total of 30 questions established a tendency. Answers exhibiting a tendency were as follows; additional diagnostic tools except for plain radiograph (magnetic resonance imaging), most common conservative treatment method (oral medication, rest), most important radiological factor in decision making for surgical treatment and method (size of the lesion, ankle instability, loose bodies), most important patient factors in decision making for surgical treatment and method (age, activity or occupation), infrequently requiring posterior arthroscopy (less than 3%), most common revision surgery for failed bone marrow stimulation procedure (osteochondral autograft transplantation [OAT]), not requiring additional procedure for donor site in OAT, the main reason for unsatisfactory result after OAT (persistent pain without radiological abnormality), no generalization of autologous chondrocyte implantation or chondrogenesis using stem cells. Conclusion: This study presents updated information on current trends in the management of OLT in Korea. Both consensus and variations in the approach to patients with OLT were revealed through this survey. Since recent biologic efforts to regenerate cartilage have been unsuccessful, further studies to identify clinical evidence would be needed.

• 한국초등과학교육학회지:초등과학교육
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• 제41권2호
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• pp.186-198
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• 2022

본 논문은 2022 교육과정 개정에 즈음하여 초등학교 과학 교육과정의 전자기 영역에서 다루어 온 내용에서 재고해야 할 문제들과 이에 대한 연구자들의 주장을 정리하여 교육과정 개선 방향에 대한 다양한 학문적 논의를 촉발하는 데 그 목적이 있다. 본 연구에서 논의된 내용을 요약하면 다음과 같다. 첫째 전자기 영역의 핵심개념은 힘의 매개체로서의 '전기장', '자기장'이라는 점에서 현재의 교육과정은 전자기 영역의 핵심개념을 담아내지 못하는 문제가 있다. 이를 해결하는 핵심개념 중심의 교육과정 구성을 위해 초등학교에서 역학과 전자기가 연계되는 것이 바람직하다. 둘째 전자기 이론에 기반한 공학기술의 발달 양상으로 본 연구에서 추출한 9가지 양상은 매우 다양한 교육적 맥락을 제공할 수 있다. 그렇지만, 현재의 교육과정은 이러한 다양한 맥락을 담아내지 못하고 있고, 전구를 활용한 전기회로라는 매우 제한된 내용에 초점을 맞추고 있다. 따라서 실생활의 기술과 연관된 다양한 맥락과 소재를 활용하도록 교육과정의 폭을 넓힐 필요가 있다. 현재보다 다양한 소재와 맥락을 활용함으로써, 개념학습뿐 아니라 STS 교육의 범위와 수준도 확장될 수 있다. 셋째, 전기회로 학습의 경우 전기회로와 전기장 개념의 연결의 어려움의 문제, 전기회로의 대표성 문제, 전기회로의 학습 난이도의 문제, 현상 중심의 전기회로 학습의 문제 등 여러 이슈를 고려해야 한다.

• 대한족부족관절학회지
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• 제26권3호
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• pp.123-129
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• 2022

Purpose: To evaluate the correlation between the fibrillar pattern of the Achilles tendon on ultrasonography (US) and functional outcomes in patients who underwent open tendon repair after Achilles tendon rupture. Materials and Methods: Data of 44 patients who had been subjected to US at least 6 months after repair, during the period between July 2012 and July 2019 were reviewed. Those with bilateral tendon rupture, re-rupture, open injury, and chronic or insertional rupture, were excluded from the review. We divided them into two groups, the homogenous group (HoP) and the heterogenous group (HeP) based on the fibrillar pattern on US. We also divided the HoP into linear and wavy subgroups, and the HeP into no hypoechoic lesion and hypoechoic lesion subgroups. The rupture type of the Achilles tendon, radiographic factors including US and magnetic resonance images, patient-related, surgical factors, and clinical results at the last visit after repair were assessed retrospectively. Results: The tendon thickness was 11.4±1.7 mm in the HoP, and 14.5±3.0 mm in the HeP (p<0.001). A shredded pattern was observed in 17 cases (65.4%) in the HoP, and in 17 cases (94.4%) in the HeP (p=0.031). The mean value of the number of sutures used was 8.9±3.05 in the HoP and 11.39±1.75 in the HeP (p=0.001). The mean value of the difference in calf circumference was 0.9±0.67 cm in the HoP and 1.36±0.71 cm in the HeP (p=0.037). There were no statistically significant differences in the fibrillar patterns and patient-related factors. Conclusion: The fibrillar pattern observed after repair was correlated with the functional outcome and showed a significant relationship with the rupture pattern and the number of sutures used. Therefore, we suggest a careful individualized postoperative rehabilitation protocol to maximize functional outcomes by referring to the fibrillar pattern in US, especially in shredded ruptures.

• Journal of Korean Neurosurgical Society
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• 제66권5호
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• pp.511-524
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• 2023

Objective : This animal model aimed to compare the rat group that received brain irradiation and did not receive additional treatment (only saline) and the rat group that underwent brain irradiation and received Granulocyte colony stimulating factor (G-CSF) treatment. In addition, the effects of G-CSF on brain functions were examined by magnetic resonance (MR) imaging and histopathologically. Methods : This study used 24 female Wistar albino rats. Drug administration (saline or G-CSF) was started at the beginning of the study and continued for 15 days after whole-brain radiotherapy (WBRT). WBRT was given on day 7 of the start of the study. At the end of 15 days, the behavioral tests, including the three-chamber sociability test, open field test, and passive avoidance learning test, were done. After the behavioral test, the animals performed the MR spectroscopy procedure. At the end of the study, cervical dislocation was applied to all animals. Results : G-CSF treatment positively affected the results of the three-chamber sociability test, open-space test and passive avoidance learning test, cornu Ammonis (CA) 1, CA3, and Purkinje neuron counts, and the brain levels of brain-derived neurotrophic factor and postsynaptic density protein-95. However, G-CSF treatment reduced the glial fibrillary acidic protein immunostaining index and brain levels of malondialdehyde, tumor necrosis factor-alpha, nuclear factor kappa-B, and lactate. In addition, on MR spectroscopy, G-CSF had a reversible effect on brain lactate levels. Conclusion : In this first designed brain irradiation animal model, which evaluated G-CSF effects, we observed that G-CSF had reparative, neuroprotective and anti-neurodegenerative effects and had increased neurotrophic factor expression, neuronal counts, and morphology changes. In addition, G-CSF had a proven lactate-lowering effect in MR spectroscopy and brain materials.

• 대한정형외과학회지
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• 제52권1호
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• pp.65-72
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• 2017

목적: 후관절 근접 낭종이 동반된 퇴행성 요추부 질환으로 수술 받은 23명의 환자를 대상으로 방사선적 특징과 임상적 결과를 분석하고자 한다. 대상 및 방법: 23명의 환자를 대상으로 척추관 협착증 동반 여부, 불안정성, 척추 전방 전위증 동반 여부, 낭종의 위치 및 방향, 후관절의 퇴행성 변화 정도, 후관절 각도, 추간판 퇴행 정도를 확인하였다. 모든 환자에게 광범위 감압술 및 기기고정 유합술을 시행하였다. 임상적 결과를 Oswestry low back pain disability questionnaire 및 visual analogue scale을 이용하여 평가하였다. 결과: 23예 중 19예(82.6%)에서 척추관 협착증이 동반되었고, 4예(17.4%)에서는 후관절 낭종이 독립적으로 존재하였다. 이 중 7예(30.4%)에서 불안정성과 전방 전위가 동반되었다. 낭종의 발생은 제4-5 요추간(69.6%)이 가장 많았으며 이환된 병변측의 후관절이 반대측에 비하여 심한 퇴행성 변화를 보였다. 후관절 각도는 좌 우측에 유의한 차이가 없었으며 해당 분절의 추간판은 17예(69.6%)에서 퇴행성 변화를 보였다. 임상적 결과는 수술 후 2년 추시 양호하였다. 결론: 낭종의 발생과 퇴행성 변화는 유의한 상관관계가 있었으며 후관절 낭종과 동반된 퇴행성 요추부 질환에서 광범위 감압술 및 유합술이 좋은 임상적 결과을 얻어 유용한 술식으로 생각된다.