• Title/Summary/Keyword: resolution methods

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Arthroscopic Decompression of Spinoglenoid Ganglion Cyst (견갑골 극관절와 결절종의 관절경하 감압술)

  • Hwang, Tae Hyok;Wang, Tae Hyun;Cho, Hyung Lae;Kim, Keun Young
    • Journal of the Korean Arthroscopy Society
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    • v.15 no.2
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    • pp.92-98
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    • 2011
  • Purpose: We describe a all-arthroscopic technique for decompression of spinoglenoid ganglion cyst and present our clinical results for this procedure. Materials and Methods: From March 2006 to June 2009, eight patients (7 males, 1 female; mean age 40.6 years; range: 21~61) were included who underwent arthroscopic decompression of spinoglenoid ganglion cyst. The most common symptoms were vague shoulder pain and external rotation weakness, which lasted 6.4 months (range: 3~8) on average. Five of eight patients were noted abnormalities on electromyographic (EMG) examination to have suprascapular nerve neuropathy and magnetic resonance imaging (MRI) showed spinoglenoid ganglion cysts in all eight patients and the cyst size was 2.6 cm (range: 1.8~3.6). Labral pathology was identified intraoperatively in all patients and the cysts were decompressed by the posterosuperior capsulotomy under arthroscopic control and labral repair with suture anchors was performed in six patients. Results: The average clinical outcome scores including Constant and Murley, Simple shoulder test (SST) all improved significantly at the time of the final follow-up and there were no complications resulting from the procedures. All patients including the patients with abnormal EMG study recovered strength on isokinetic strength testing. Follow-up MRI scans were performed on all patients at a mean of 5.2 months postoperatively (range: 3~12) revealed complete resolution of the cysts and no evidence of recurrences were seen at an average of 18 months (range: 12~26) of follow-up. Conclusion: Arthroscopic decompression of spinoglenoid ganglion cyst effectively restores patient function and all patients in this study showed improvement in their postoperative MRI findings. Arthroscopic decompression is also useful in the appropriate treatment for labral pathology and may contribute to decreased risk of cyst recurrence.

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Outcome of Prenatally Diagnosed Hydronephrosis - One Center Experience - (산전 진단된 수신증의 임상 경과 - 단일 기관의 경험 -)

  • Kim Yeun-Hee;Kim Byoung-Ju;Park Moon-Sung;Yang Jung-In;Kim Haeng-Soo;Kim Pyung-Kil;Pai Ki-Soo
    • Childhood Kidney Diseases
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    • v.6 no.2
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    • pp.178-187
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    • 2002
  • Purpose : The detection of hydronephrosis(HN) with antenatal ultrasonography was first reported in the 1970s. Prenatal HN is diagnosed with an incidence of 1:100 to 1:500 on antenatal screening. Recently, the purpose of antenatal screening has changed from simple detection to selection for specific diagnosis-based management. this study is to evaluate the usefulness of antenatal sonography for HN and to investigate the differential causes of HN and their clinical outcomes. Patients and methods : 11,783 live neonates with prenatal ultrasonographic examination at Ajou University School of Medicine, from Sep. 1994 to Aug. 2001 were analyzed. Results and conclusion : Hydronephrosis (>10 mm) was detected in 119 (1.0%) cases antenatally and among these, 91 were proved to have HN postnatally Males were three times more affected than females. Additional imaging studies revealed that ureteropelvic junction obstruction was the most common postnatal diagnosis (47%), followed by multicystic dysplastic kidney, vesicoureteral junction obstruction and vesicoureteral reflux. During 20 months' follow-up(3 to 72 months), 58(48%) renal units showed spontaneous resolution and surgical interventions were necessary in 10 (7.4%) of postnatally confirmed hydronephrotic renal units.

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Performance Evaluation of Breast Specific Gamma Imaging (Breast Specific Gamma Imaging 장비의 성능평가)

  • Cha, Eun-Sun;Kwak, In-Suk;Noh, Ik-Sang;Yeon, Joon-Ho;Kim, Ki;Choi, Choon-Ki;Seok, Jae-Dong
    • The Korean Journal of Nuclear Medicine Technology
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    • v.14 no.1
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    • pp.24-27
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    • 2010
  • Purpose: Early diagnosis of breast is of the utmost importance to improve prognosis. We have a limitation for mammography and sonography detecting small cancer. Clinical importance of Breast Specific Gamma Imaging (BSGI) has improved for that reason. So We studied performance evaluation test of count rate and resolution with high sensitivity to the low dose of BSGI. Materials and Methods: BSGI of Dilon 6800, point source of $^{99m}Tc$ from 1.85~148 MBq (0.05~4 mCi) at the intervals of 1.85~37 MBq (0.05~1 mCi) was used for the test. Performance evaluation method was performed for measuring deadtime for choosing at the 5 different point in the useful field of view (UFOV), acquired image for 60 seconds. Compared with reference of clinical uptake distribution of breast, activity increased according to the distance change 10, 20, 30, 40, 50 mm in the useful field of view. Results: Counting curve increased according to the activity from 1.85 MBq (0.05 mCi) to the 74 MBq (2 mCi), and it change flat shape over 74 MBq (2 mCi). The variation of the full width of half maximum (FWHM) to the distance is 4.05, 4.73, 5.77, 6.90, 8.00, 9.32 mm in 1.85 MBq (0.05 mCi), 4.30, 4.80, 5.90, 7.00, 8.10, 9.07 mm in 3.7 MBq (0.1 mCi), 4.90, 5.60, 6.20, 7.20, 8.20, 9.10 mm in 5.55 MBq (0.15 mCi), 5.30, 6.10, 6.60, 7.00, 7.90, 8.70 mm in 7.40 MBq (0.2 mCi). Conclusion: Distortions of image would be acquired because of the deadtime in BSGI. We found out the fact that specification of $^{99m}Tc$ reaction under 74 MBq (2 mCi) for BSGI. Second, FWHM distribution change from varied distance from the detector, clearly distinguished the location of the lesion.

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The Optimization of Reconstruction Method Reducing Partial Volume Effect in PET/CT 3D Image Acquisition (PET/CT 3차원 영상 획득에서 부분용적효과 감소를 위한 재구성법의 최적화)

  • Hong, Gun-Chul;Park, Sun-Myung;Kwak, In-Suk;Lee, Hyuk;Choi, Choon-Ki;Seok, Jae-Dong
    • The Korean Journal of Nuclear Medicine Technology
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    • v.14 no.1
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    • pp.13-17
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    • 2010
  • Purpose: Partial volume effect (PVE) is the phenomenon to lower the accuracy of image due to low estimate, which is to occur from PET/CT 3D image acquisition. The more resolution is declined and the lesion is small, the more it causes a big error. So that it can influence the test result. Studied the optimum image reconstruction method by using variation of parameter, which can influence the PVE. Materials and Methods: It acquires the image in each size spheres which is injected $^{18}F$-FDG to hot site and background in the ratio 4:1 for 10 minutes by using NEMA 2001 IEC phantom in GE Discovey STE 16. The iterative reconstruction is used and gives variety to iteration 2-50 times, subset number 1-56. The analysis's fixed region of interest in detail part of image and compute % difference and signal to noise ratio (SNR) using $SUV_{max}$. Results: It's measured that $SUV_{max}$ of 10 mm spheres, which is changed subset number to 2, 5, 8, 20, 56 in fixed iteration to times, SNR is indicated 0.19, 0.30, 0.40, 0.48, 0.45. As well as each sphere's of total SNR is measured 2.73, 3.38, 3.64, 3.63, 3.38. Conclusion: In iteration 6th to 20th, it indicates similar value in % difference and SNR ($3.47{\pm}0.09$). Over 20th, it increases the phenomenon, which is placed low value on $SUV_{max}$ through the influence of noise. In addition, the identical iteration, it indicates that SNR is high value in 8th to 20th in variation of subset number. Therefore, to reduce partial volume effect of small lesion, it can be declined the partial volume effect in iteration 6 times, subset number 8~20 times, considering reconstruction time.

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Clinical Manifestations of PFAPA (Periodic Fever, Aphthous Stomatitis, Pharyngitis, and Adenitis) Syndrome from a Single Center (단일기관에서 진단한 PFAPA (Periodic Fever, Aphthous Stomatitis, Pharyngitis, and Adenitis) 증후군의 임상양상)

  • Shin, Minsoo;Choi, Eun Hwa;Han, Mi Seon
    • Pediatric Infection and Vaccine
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    • v.26 no.3
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    • pp.179-187
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    • 2019
  • Purpose: Periodic fever, aphthous stomatitis, pharyngitis, and adenitis (PFAPA) syndrome is a leading cause of periodic fever in children. This study describes the clinical characteristics of PFAPA syndrome in patients from a single center. Methods: Thirteen children diagnosed with PFAPA syndrome at Seoul National University Children's Hospital were included in this study. Retrospective medical chart reviews were performed. Results: Among the 13 patients, 8 (61.5%) were male. The median follow-up duration was 3.3 years (range, 10 months-8.3 years). The median age of periodic fever onset was 3 years (range, 1-6 years). All patients had at least 5 episodes of periodic fever and pharyngitis, managed with oral antibiotics, before diagnosis. The median occurrence of fever was every 3.9 weeks and lasted for 4.2 days. All patients had pharyngitis and 12 (92.3%) had cervical lymphadenitis. Blood tests were performed for 12 patients, and no patients had neutropenia. Both the C-reactive protein and erythrocyte sedimentation rate were elevated at medians of 4.5 mg/dL (range, 0.4-13.2 mg/dL) and 29 mm/hr (range, 16-49 mm/hr), respectively. Throat swab cultures and rapid streptococcal antigen tests were negative. Nine (69.2%) patients received oral prednisolone at a median dose of 0.8 mg/kg, and in 6 (66.7%) patients, fever resolved within a few hours. Three (23.1%) patients received tonsillectomy and adenoidectomy. Conclusions: PFAPA syndrome should be considered when a child presents with periodic fever along with aphthous stomatitis, pharyngitis, or cervical lymphadenitis. Glucocorticoid administration is effective for fever resolution and can reduce unnecessary use of antibiotics.

Results of Stereotactic Radiosurgerv with Linear Accelerator for Intracranial Arteriovenous Malformation (두개강내 동정맥기형에서 선형가속기를 이용한 방사선수술의 결과)

  • Lee Kang Kyoo;Park Kyung Ran;Lee Jong Young;Lee Yong Ha
    • Radiation Oncology Journal
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    • v.15 no.3
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    • pp.215-224
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    • 1997
  • Purpose : Stereotactic radiosurgery with external beam irradiation successfully obliterates carefully selected intracranial arteriovenous malformation (AVM) . We Present clinical and radiological long term results after treatment with a single high dose irradiation using a linear accelerator. Materials and Methods : Rrom January 1991 to June 1994, fifteen patients with intracranial AVM were treated in our hospital with the stereotactic radiosurgery using a linear accelerator. The radiation was delivered using a 6 MV linear accelerator. The prescribed doses at the isocenter varied from 1800 to 2500cGy (median : 2000cGy) and were given as a sin91e fraction. The radiation doses at the periphery of the lesion typically corresponded to the 80-90% isodose line. In 14 patients, complete clinical and/or radiological follow-up examination were available. Results : Angiography was available in 13 patients with a follow-up Period from 18 months to 27 months. Of 13 patients, the overall complete obliteration rate was 92.3% (12 patients). This incidence did not correlate with lesion size. Seizure, headache and progressive neurologic deficit were complete recovered. One Patient experienced hemorrhage at 2 months after treatment. One patient developed radiation induced brain edema in the white matter surrounding nidus at 16 months after treatment and showed complete resolution of the edema in MR image obtained at 27 months after treatment. After a follow-up period of up to 6 years, no radiation induced severe late complications occurred. Conclusion : We conclude that stereotactic radiosurgery using a linear accelerator is an effective and safe therapy for symptomatic and surgically inaccessible intracranial AVMs and the results compare favorably to the more expensive and elaborate systems that are currently available for stereotactic radiosurgery.

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The Correlation of Dyspnea and Radiologic Quantity in Patients with COPD (만성폐쇄성폐질환 환자에서 호흡곤란과 영상학적 정량과의 상관관계)

  • Jung, Eun Jung;Kim, Yang Ki;Lee, Young Mok;Kim, Ki-Up;Uh, Soo-Taek;Kim, Yong Hoon;Kim, Do Jin;Park, Choon Sik;Hwang, Jung Hwa
    • Tuberculosis and Respiratory Diseases
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    • v.66 no.4
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    • pp.288-294
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    • 2009
  • Background: A lung hyperinflation, or air trapping, caused by expiratory flow-limitation contributes to dyspnea in patients with chronic obstructive pulmonary disease (COPD). Forced expiratory volume in 1 second ($FEV_1$) has served as an important diagnostic measurement of COPD, but does not correlate with patient-centered outcomes such as dyspnea. Therefore, this study was performed to investigate the role of radiologic quantity in evaluating the dyspnea in patients with COPD by measuring lung hyperinflation in chest x-ray and high resolution chest tomography (HRCT). Methods: Fifty patients with COPD were enrolled in this study. Their subjective dyspnea score (modified Borg scale dyspnea index), spirometry, and lung volume were measured. Simultaneous hyperinflations of chest x-ray score ("chest score") and degree of emphysema of HRCT ("HRCT score") were measured. The "chest score" were composed of lung length, retrosternal space width, and height of the arc of the diaphragm and "HRCT score" were composed of severity and extent of emphysema. Results: The mean age of patients was 69 years old and their mean $FEV_1$ was 51.7%. The Borg score significantly correlated with parameters of spirometry and lung volume, including FVC, $FEV_1$, $FEV_1$/FVC, RV, RV/TLC, and DLCO. The Borg score correlated well with "HRCT score", but did not correlate with "chest score". Also, the Borg scale correlates inversely with body mass index. Conclusion: The quantity of emphysema on chest HRCT may serve as an objective marker of dyspnea in patients with COPD.

Preoperative Evaluation of Lower Rectal Cancer by Pelvic MR with and without Gel Filling (하부직장암 환자에서 초음파겔 삽입 전후의 골반 자기공명영상의 비교)

  • Kim, Dae Jung;Kim, Joo Hee;Lim, Joon Seok;Chung, Jae-Joon;Yu, Jeong-Sik;Kim, Myeong-Jin;Kim, Ki Whang
    • Investigative Magnetic Resonance Imaging
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    • v.18 no.4
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    • pp.323-331
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    • 2014
  • Purpose : To assess the usefulness of rectal filling using ultrasonographic gel in patients with lower rectal cancer. Materials and Methods: Twenty five patients with lower rectal cancer were enrolled. High resolution pelvic MR was performed twice before and after gel filling. Independently and retrospectively, two radiologists reviewed each set of MR images using five-grade scales for sphincter involvement, CRM (circumferential resection margin) involvement and depiction of the tumor. Same two radiologists retrospectively performed consensus review of each set of MR images for tumor distance from the anal verge and T&N staging. Results: Tumor depiction scores from MR with gel filling were significantly higher than those of MR without distention (p<0.001). Compared to MR without distension, MR with gel filling had no significant differences in prediction of CRM or sphincter involvement (p>0.05). Distance from the anal verge was significantly different between MR with gel filling and rigid endoscopy ($6.8{\pm}1.6cm$ vs. $5.8{\pm}1.6cm$, p=0.001). There were no significant differences between pathological staging and MR staging with or without gel filling. Conclusion: MR with gel filling improved tumor depiction. And also MR with gel filling revealed same ability for the predictions of CRM or sphincter invasion in patients with lower rectal cancer, comparing with MR without gel filling.

Transient Splenial Lesions in the Splenium of Corpus Callosum in Seven Patients: MR Findings and Clinical Correlations (뇌량 팽대의 일과성 병변: 7명의 환자에서의 자기공명 영상소견과 임상 양상의 연관성)

  • Park, Ju Young;Lee, In Ho;Song, Chang June;Hwang, Hee Youn
    • Investigative Magnetic Resonance Imaging
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    • v.17 no.1
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    • pp.1-7
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    • 2013
  • Purpose : The purpose of this study is to correlate the imaging findings and the clinical findings in patients with transient splenial lesions (TSL). Materials and Methods: Total of 7 patients (M: F = 4: 3; age range 11 - 38 years, mean age 25.5 years) were studied between November 2006 and April 2011. The MRI findings and clinical findings in all patients were retrospectively reviewed. The location, MR signal intensity, restricted diffusion, enhancement pattern and reversibility from the follow up images were reviewed. Clinical features were reviewed with respect to the presented symptoms, signs, treatment and outcome. Results: The lesions were located in the splenium of corpus callosum in all patients. All lesions showed high signal intensity on diffusion weighted imaging (DWI), and six patients showed restricted diffusion on the apparent diffusion coefficient (ADC) map. ADC map was not available in one patient. All lesions (n = 7) showed high signal intensity on the T2 weighted image (T2WI). Five of the patients (71.4%) with follow up images (range 7 - 34 days) showed complete resolution of focal high signal intensity on DWI, with recovery of ADC values as well as T2WI. After contrast media administration, none of the lesions showed any enhancements. All lesions with various etiologies including TB medication were developed in younger age patients and showed reversibility after the acceptable period of minimum 7 days with conservative treatment. Conclusion: All TSL showed nonspecific imaging findings, including restricted diffusion on DWI and ADC map on the initial images. However, reversibility of the lesions and the young age preference can be a characteristic finding of TSL with acceptable period of minimum 7 days. In addition, to keep it in mind that various etiologies including TB medication may cause TSL, is important for radiologists as well as clinicians.

Accuracy of F-18 FDG PET/CT in Preoperative Assessment of Cervical Lymph Nodes in Head and Neck Squamous Cell Cancer: Comparison with CT/MRI (두경부 편평상피암 환자에서 수술 전 경부림프절 전이 평가에 대한 F-18 FDG PET/CT의 정확도: CT/MRI와의 비교)

  • Choi, Seung-Jin;Byun, Sung-Su;Park, Sun-Won;Kim, Young-Mo;Hyun, In-Young
    • Nuclear Medicine and Molecular Imaging
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    • v.40 no.6
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    • pp.309-315
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    • 2006
  • Purpose: Accurate evaluation of cervical lymph node (LN) metastasis of head and neck squamous cell canter (SCC) is important to treatment planning. We evaluated the diagnostic accuracy of F-18 fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) for the detection of cervical LN metastasis of head and neck SCC and performed a retrospective comparison with CT/MRI findings. Materials & Methods: Seventeen patients with pathologically proven head and neck SCC underwent F-18 FDG PET/CT and CT/MRI within 4 week before surgery. We recorded lymph node metastases according to the neck level system of imaging-based nodal classification. F-18 FDG PET/CT images were analyzed visually for assessment of regional tracer uptake in LN. We analyzed the differences in sensitivity and specificity between F-18 FDG PET/CT and CT/MRI using the Chi-square test. Results: Among the 17 patients, a total of 123 LN levels were dissected, 29 of which showed metastatic involvement. The sensitivity and specificity of F-18 FDG PET/CT for detecting cervical LN metastasis on a level-by-level basis were 69% (20/29) and 99% (93/94). The sensitivity and specificity of CT/MRI were 62% (18/29) and 96% (90/94). There was no significant difference in diagnostic accuracy between F-18 FDG PET/CT and CT/MRI. Interestingly, F-18 FDG PET/CT detected double primary tumor (hepatocellular carcinoma) and rib metastasis, respectively. Conclusion: There was not statistically significant difference of diagnostic accuracy between F-18 FDG PET/CT and CT/MRI for the detection of cervical LN metastasis of head and neck SCC. The low sensitivity of F-18 FDG PET/CT was due to limited resolution for small metastatic deposits.