1.Stress Fracture of the Capitate
Hyung Joon CHO ; Ki Taek HONG ; Chang Ho KANG ; Kyung Sik AHN ; Yura KIM ; Sung Tae HWANG
Investigative Magnetic Resonance Imaging 2018;22(2):135-139
Most capitate fractures occur in association with additional carpal injuries, particularly scaphoid fractures. Isolated fractures of the capitate account for only 0.3% of carpal injuries, and stress fractures are one form of this fracture. We report the case of a 20-year-old male who had a stress fracture of the capitate after serving as an honor guard in the military. Conventional radiographs and computed tomography of the right wrist revealed a minimally displaced fracture line located at the midcarpal aspect of the right capitate. A magnetic resonance imaging scan demonstrates a subarticular capitate fracture with diffuse bone marrow edema, small osteophytes, and irregularity of the midcarpal articular cartilage. We also review the carpal kinematics which possibly caused the stress fracture. Although stress fractures of the capitate are rare, they should also be accounted for with patients who perform repetitive motions of the wrist to a considerable extent.
Biomechanical Phenomena
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Bone Marrow
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Capitate Bone
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Carpal Bones
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Cartilage, Articular
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Edema
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Fractures, Stress
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Humans
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Magnetic Resonance Imaging
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Male
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Military Personnel
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Multidetector Computed Tomography
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Osteophyte
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Wrist
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Young Adult
2.Xanthoma Simulating Plantar Fibromatosis on Sonography.
Yura KIM ; Kyung Sik AHN ; Chang Ho KANG
Journal of the Korean Society of Medical Ultrasound 2013;32(3):189-192
Xanthomas are local collections of lipid-laden macrophages and collagen, which are usually associated with impaired lipoprotein metabolism. Xanthomas occur frequently in the skin, subcutis, or tendon, and occasionally in the plantar fascia. Small numbers of xanthomas have been surgically confirmed in the plantar fascia and their sonographic appearance has not been described in the literature. We present sonographic findings of a pathologically proven plantar fascia xanthoma, which was initially mistaken as plantar fibromatosis.
Collagen
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Fascia
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Fibroma*
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Foot
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Lipoproteins
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Macrophages
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Metabolism
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Skin
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Tendons
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Ultrasonography
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Xanthomatosis*
3.An Unusual Cause of Knee Pain: Periosteal Glomus Tumor of the Distal Femur
Hyung Joon CHO ; Kyung Sik AHN ; Chang Ho KANG ; Yura KIM ; Jong Hoon PARK
Journal of the Korean Radiological Society 2018;79(2):106-109
Glomus tumors are rare neoplasms that characteristically occur in subungual regions, but may also be found in other regions of the body. The clinical diagnosis of this tumor may be difficult if the tumor is located in an extradigital site. Most extradigital glomus tumors form in superficial locations. Herein, we present the case of a 34-year-old woman who experienced chronic knee pain with pinpoint tenderness resulting from a deep-seated periosteal glomus tumor of the distal femur. Extradigital glomus tumors should be considered in the differential diagnosis when characteristic clinical features and imaging findings indicative of glomus tumors are present, even if the tumor is located within deep tissues.
4.Tricuspid Valve Imaging and Right Ventricular Function Analysis Using Cardiac CT and MRI
Yura AHN ; Hyun Jung KOO ; Joon-Won KANG ; Dong Hyun YANG
Korean Journal of Radiology 2021;22(12):1946-1963
Cardiac computed tomography (CT) and cardiac magnetic resonance imaging (CMR) can reveal the detailed anatomy and function of the tricuspid valve and right ventricle (RV). Quantification of tricuspid regurgitation (TR) and analysis of RV function have prognostic implications. With the recently available transcatheter treatment options for diseases of the tricuspid valve, evaluation of the tricuspid valve using CT and CMR has become important in terms of patient selection and procedural guidance. Moreover, CT enables post-procedural investigation of the causes of valve dysfunction, such as pannus or thrombus. This review describes the anatomy of the tricuspid valve and CT and CMR imaging protocols for right heart evaluation, including RV function and TR analyses. We also demonstrate the pre-procedural planning for transcatheter treatment of TR and imaging of postoperative complications using CT.
5.Primary Extragonadal Germ Cell Tumors in Klinefelter Syndrome: 10-Years of Experience from a Single Institute
Yura KIM ; Won Kee AHN ; Jung Woo HAN ; Seung Min HAHN ; Seung Yeon KWON ; Chuhl Joo LYU
Clinical Pediatric Hematology-Oncology 2020;27(1):61-66
Background:
Approximately 8% of male patients presenting with primary mediastinal germ cell tumors (GCTs) have Klinefelter syndrome (KS), while patients diagnosed with retroperitoneal GCTs also exhibit a range of chromosomal abnormalities. The exact mechanism underlying the development of GCTs in Klinefelter syndrome is unknown, but KS frequently goes underdiagnosed as a result of its varied symptoms and a low general awareness of this condition. Thus, the Children’s Oncology Group recommends screening of Klinefelter syndrome in pediatric and adolescent male subjects who present with GCTs.
Methods:
We retrospectively reviewed the medical records of extragonadal germ cell tumor patients treated at Severance hospital, department of pediatrics or division of pediatric hematology-oncology over the last ten years.
Results:
A total of 95 patients with extragonadal germ cell tumors were included in this study. Karyotyping was done in eight patients out of 95 patients, three patients with KS and one patient with Down syndrome. Twelve of extragonadal GCT patients presented at mediastinum, with most common histology of mature teratoma, and three patients presented with chromosomal abnormalities, two with KS and one with Down syndrome. A total of nine patients were diagnosed with retroperitoneal GCTs and only one had KS.
Conclusion
We described the characteristics of 95 cases of extragonadal GCTs. Although the mechanism of extragonadal GCTs in KS is not clear, karyotyping in pediatric and adolescent extragonadal GCT patients could be helpful in figuring out chromosomal abnormalities including KS and their roles in GCT pathophysiology, which can contribute to improve one’s health.
6.Prescription Refill Gap of Endocrine Treatment from Electronic Medical Records as a Prognostic Factor in Breast Cancer Patients
Yura LEE ; Yu Rang PARK ; Ji Sung LEE ; Sae Byul LEE ; Il Yong CHUNG ; Byung Ho SON ; Sei Hyun AHN ; Jong Won LEE
Journal of Breast Cancer 2019;22(1):86-95
PURPOSE: Discontinuation of hormone therapy is known to lead to a poorer prognosis in breast cancer patients. We aimed to investigate the prescription gap as a prompt index of medication adherence by using prescription data extracted from patient electronic medical records. METHODS: A total of 5,928 patients diagnosed with invasive, non-metastatic breast cancer, who underwent surgery from January 1, 1997 to December 31, 2009, were enrolled retrospectively. The prescription data for 4.5 years of hormonal treatment and breast cancer-related events after treatment completion were analyzed. We examined the characteristics and prognoses of breast cancer in patients with and without a 4-week gap. RESULTS: Patients with a gap showed a significantly higher risk of breast cancer recurrence, distant metastasis, breast cancer-specific death, and overall death after adjustment (hazard ratio [HR], 1.389; 95% confidence interval [CI], 1.089–1.772; HR, 1.568; 95% CI, 1.158–2.123; HR, 2.108; 95% CI, 1.298–3.423; and HR, 2.102; 95% CI, 1.456–3.034, respectively). When patients were categorized based on gap summation, the lower third (160 days) and fourth (391 days) quartiles showed a significantly higher risk of distant metastasis (HR, 1.758; 95% CI, 1.186–2.606 and HR, 1.844; 95% CI, 1.262–2.693, respectively). CONCLUSION: A gap of > 4 weeks in hormonal treatment has negative effects on breast cancer prognosis, and can hence be used as a sentinel index of higher risk due to treatment non-adherence. Further evaluation is needed to determine whether the gap can be used as a universal index for monitoring the adherence to hormonal treatment.
Breast Neoplasms
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Breast
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Electronic Health Records
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Estrogen Antagonists
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Humans
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Medication Adherence
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Neoplasm Metastasis
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Prescriptions
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Prognosis
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Recurrence
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Retrospective Studies
7.Impact of the Liver Imaging Reporting and Data System on Research Studies of Diagnosing Hepatocellular Carcinoma Using MRI
Yura AHN ; Sang Hyun CHOI ; Jong Keon JANG ; So Yeon KIM ; Ju Hyun SHIM ; Seung Soo LEE ; Jae Ho BYUN
Korean Journal of Radiology 2022;23(5):529-538
Objective:
Since its introduction in 2011, the CT/MRI diagnostic Liver Imaging Reporting and Data System (LI-RADS) has been updated in 2014, 2017, and 2018. We evaluated the impact of CT/MRI diagnostic LI-RADS on liver MRI research methodology for the diagnosis of hepatocellular carcinoma (HCC).
Materials and Methods:
The MEDLINE, EMBASE, and Cochrane databases were searched for original articles reporting the diagnostic performance of liver MRI for HCC between 2011 and 2019. The MRI techniques, image analysis methods, and diagnostic criteria for HCC used in each study were investigated. The studies were classified into three groups according to the year of publication (2011–2013, 2014–2016, and 2017–2019). We compared the percentage of studies adopting MRI techniques recommended by LI-RADS, image analysis methods in accordance with the lexicon defined in LI-RADS, and diagnostic criteria endorsed by LI-RADS. We compared the pooled sensitivity and specificity between studies that used the LI-RADS and those that did not.
Results:
This systematic review included 179 studies. The percentages of studies using imaging techniques recommended by LI-RADS were 77.8% for 2011–2013, 85.7% for 2014–2016, and 84.2% for 2017–2019, with no significant difference (p = 0.951). After the introduction of LI-RADS, the percentages of studies following the LI-RADS lexicon were 0.0%, 18.4%, and 56.6% in the respective periods (p < 0.001), while the percentages of studies using the LI-RADS diagnostic imaging criteria were 0.0%, 22.9%, and 60.7%, respectively (p < 0.001). Studies that did not use the LI-RADS and those that used the LIRADS version 2018 showed no significant difference in sensitivity and specificity (86.3% vs. 77.7%, p = 0.102 and 91.4% vs. 89.9%, p = 0.770, respectively), with some difference in heterogeneity (I2 = 94.3% vs. 86.7% in sensitivity and I2 = 86.6% vs. 53.2% in specificity).
Conclusion
LI-RADS imparted significant changes in the image analysis methods and diagnostic criteria used in liver MRI research for the diagnosis of HCC.
8.Rare Neurovascular Diseases in Korea: Classification and Related Genetic Variants
Yunsun SONG ; Boseong KWON ; Abdulrahman Hamed AL-ABDULWAHHAB ; Yeo Kyoung NAM ; Yura AHN ; So Yeong JEONG ; Eul-Ju SEO ; Jong-Keuk LEE ; Dae Chul SUH
Korean Journal of Radiology 2021;22(8):1379-1396
Rare neurovascular diseases (RNVDs) have not been well-recognized in Korea. They involve the central nervous system and greatly affect the patients’ lives. However, these diseases are difficult to diagnose and treat due to their rarity and incurability. We established a list of RNVDs by referring to the previous literature and databases worldwide to better understand the diseases and their current management status. We categorized 68 RNVDs based on their pathophysiology and clinical manifestations and estimated the prevalence of each disease in Korea. Recent advances in genetic, molecular, and developmental research have enabled further understanding of these RNVDs. Herein, we review each disease, while considering its classification based on updated pathologic mechanisms, and discuss the management status of RNVD in Korea.
9.Development and Validation of a Simple Index Based on Non-Enhanced CT and Clinical Factors for Prediction of Non-Alcoholic Fatty Liver Disease
Yura AHN ; Sung Cheol YUN ; Seung Soo LEE ; Jung Hee SON ; Sora JO ; Jieun BYUN ; Yu Sub SUNG ; Ho Sung KIM ; Eun Sil YU
Korean Journal of Radiology 2020;21(4):413-421
OBJECTIVE: A widely applicable, non-invasive screening method for non-alcoholic fatty liver disease (NAFLD) is needed. We aimed to develop and validate an index combining computed tomography (CT) and routine clinical data for screening for NAFLD in a large cohort of adults with pathologically proven NAFLD.MATERIALS AND METHODS: This retrospective study included 2218 living liver donors who had undergone liver biopsy and CT within a span of 3 days. Donors were randomized 2:1 into development and test cohorts. CT(L-S) was measured by subtracting splenic attenuation from hepatic attenuation on non-enhanced CT. Multivariable logistic regression analysis of the development cohort was utilized to develop a clinical-CT index predicting pathologically proven NAFLD. The diagnostic performance was evaluated by analyzing the areas under the receiver operating characteristic curve (AUC). The cutoffs for the clinical-CT index were determined for 90% sensitivity and 90% specificity in the development cohort, and their diagnostic performance was evaluated in the test cohort.RESULTS: The clinical-CT index included CT(L-S), body mass index, and aspartate transaminase and triglyceride concentrations. In the test cohort, the clinical-CT index (AUC, 0.81) outperformed CT(L-S) (0.74; p < 0.001) and clinical indices (0.73–0.75; p < 0.001) in diagnosing NAFLD. A cutoff of ≥ 46 had a sensitivity of 89% and a specificity of 41%, whereas a cutoff of ≥ 56.5 had a sensitivity of 57% and a specificity of 89%.CONCLUSION: The clinical-CT index is more accurate than CT(L-S) and clinical indices alone for the diagnosis of NAFLD and may be clinically useful in screening for NAFLD.
10.Deep Learning Algorithm for Automated Segmentationand Volume Measurement of the Liver and Spleen UsingPortal Venous Phase Computed Tomography Images
Yura AHN ; Jee Seok YOON ; Seung Soo LEE ; Heung-Il SUK ; Jung Hee SON ; Yu Sub SUNG ; Yedaun LEE ; Bo-Kyeong KANG ; Ho Sung KIM
Korean Journal of Radiology 2020;21(8):987-997
Objective:
Measurement of the liver and spleen volumes has clinical implications. Although computed tomography (CT)volumetry is considered to be the most reliable noninvasive method for liver and spleen volume measurement, it has limitedapplication in clinical practice due to its time-consuming segmentation process. We aimed to develop and validate a deeplearning algorithm (DLA) for fully automated liver and spleen segmentation using portal venous phase CT images in variousliver conditions.
Materials and Methods:
A DLA for liver and spleen segmentation was trained using a development dataset of portal venousCT images from 813 patients. Performance of the DLA was evaluated in two separate test datasets: dataset-1 which included150 CT examinations in patients with various liver conditions (i.e., healthy liver, fatty liver, chronic liver disease, cirrhosis,and post-hepatectomy) and dataset-2 which included 50 pairs of CT examinations performed at ours and other institutions.The performance of the DLA was evaluated using the dice similarity score (DSS) for segmentation and Bland-Altman 95%limits of agreement (LOA) for measurement of the volumetric indices, which was compared with that of ground truth manualsegmentation.
Results:
In test dataset-1, the DLA achieved a mean DSS of 0.973 and 0.974 for liver and spleen segmentation, respectively,with no significant difference in DSS across different liver conditions (p = 0.60 and 0.26 for the liver and spleen, respectively).For the measurement of volumetric indices, the Bland-Altman 95% LOA was -0.17 ± 3.07% for liver volume and -0.56 ± 3.78%for spleen volume. In test dataset-2, DLA performance using CT images obtained at outside institutions and our institutionwas comparable for liver (DSS, 0.982 vs. 0.983; p = 0.28) and spleen (DSS, 0.969 vs. 0.968; p = 0.41) segmentation.
Conclusion
The DLA enabled highly accurate segmentation and volume measurement of the liver and spleen using portalvenous phase CT images of patients with various liver conditions.