Pathology-MRI Correlation of Hepatocarcinogenesis: Recent Update

허지미,김경원,김지훈,유은실 대한병리학회 2015 Journal of Pathology and Translational Medicine Vol.49 No.3

Understanding the important alterations during hepatocarcinogenesis as well as the characteristic magnetic resonance imaging (MRI) and histopathological features will be helpful for managing patients with chronic liver disease and hepatocellular carcinoma. Recent advances in MRI techniques, such as fat/iron quantification, diffusion-weighted images, and gadoxetic acid-enhanced MRI, have greatly enhanced our understanding of hepatocarcinogenesis.

Comparative Study between Digital Tomosynthesis and Endoscopic Retrograde Cholangiopancreatography for the Evaluation of Common Bile Duct Stones: Focus on Detection and Stone Conspicuity

허지미,백승연,황윤미,이정경,김유경,이선영 대한영상의학회 2011 대한영상의학회지 Vol.65 No.5

Purpose: To compare digital tomosynthesis with endoscopic retrograde cholangiopancreatography (ERCP) for the evaluation of common bile duct (CBD) stones as a complementary diagnostic tool. Materials and Methods: Ninety six consecutive patients clinically suspected of having CBD stones underwent ERCP and digital tomosynthesis over 22 months, from December, 2008 to May, 2010. Fourteen patients were excluded. Therefore 82 patients were included in this study. The images were retrospectively reviewed to compare the results with the final analysis based on the consensus of two abdominal radiologists. An evaluation of the presence of CBD stones was followed by a determination of the margins for the stones, scored with a five-point conspicuity scale. Results: Among the 82 patients, 54 collectively had 89 CBD stones and 28 had no stones. The sensitivity and specificity for the detection of CBD stones were 91.0% and 80.6% for ERCP, 92.1% and 93.5% for digital tomosynthesis, respectively. The average score was 3.29 for ERCP and 3.89 for digital tomosynthesis in 77 similar detected stones. Digital tomosynthesis demonstrated significantly better conspicuity than ERCP (p = 0.001). Conclusion: Digital tomosynthesis is an effective and complementary diagnostic method for the evaluation of CBD stones.

Prognostic Value of Skeletal Muscle Depletion Measured on Computed Tomography for Overall Survival in Patients with Non-Metastatic Breast Cancer

허지미,박범희,이혜림,안영실,정용식,김지영,강두경,김경원,김태희 한국유방암학회 2020 Journal of breast cancer Vol.23 No.1

Purpose: The purpose of this study was to evaluate the prognostic value of skeletal muscle depletion measured on computed tomography (CT) in patients with non-metastatic invasive breast cancer. Methods: This retrospective study included 577 consecutive women (mean age ± standard deviation: 48.9 ± 10.2 years with breast cancer who underwent a preoperative positronemission tomography (PET)/CT scan and curative surgery between January 2012 and August 2014. The total abdominal muscle area (TAMA), subcutaneous fat area (SFA), and visceral fat area (VFA) were measured on CT images at the L3 vertebral level. Univariate and multivariate Cox proportional-hazard regression analyses were performed to evaluate whether there was an association between sarcopenia and overall survival (OS) outcome. Results: Of the 577 women, 49 (8.5%) died after a mean of 46 months. The best TAMA threshold for predicting OS was 83.7 cm2 . The multivariate Cox proportional-hazard analysis revealed that sarcopenia (TAMA ≤ 83.70 cm2 ) was a strong prognostic biomarker (hazard ratio [HR], 1.951; 95% confidence interval [CI], 1.061–3.586), along with large tumor size, axillary lymph node metastasis, high nuclear grade, estrogen receptor status, and adjuvant radiation therapy. In the subgroup analysis of patients aged ≥ 50 years, TAMA (≤ 77.14 cm2 ) was a significant independent factor (HR, 2.856; 95% CI, 1.218–6.695). Conclusion: Skeletal muscle depletion measured on CT was associated with worse OS outcome in patients with non-metastatic breast cancer

Imaging Features of Primary Tumors and Metastatic Patterns of the Extraskeletal Ewing Sarcoma Family of Tumors in Adults: A 17-Year Experience at a Single Institution

허지미,김경원,Seong Joon Park,김형중,이종석,하현권,Sree Harsha Tirumani,Nikhil H. Ramaiya 대한영상의학회 2015 Korean Journal of Radiology Vol.16 No.4

To comprehensively analyze the spectrum of imaging features of the primary tumors and metastatic patterns of the Extraskeletal Ewing sarcoma family of tumors (EES) in adults. We performed a computerized search of our hospital’s data-warehouse from 1996 to 2013 using codes for Ewing sarcoma and primitive neuroectodermal tumors as well as the demographic code for ≥ 18 years of age. We selected subjects who were histologically confirmed to have Ewing sarcoma of extraskeletal origin. Imaging features of the primary tumor and metastatic disease were evaluated for lesion location, size, enhancement pattern, necrosis, margin, and invasion of adjacent organs. Among the 70 patients (mean age, 35.8 ± 15.6 years; range, 18–67 years) included in our study, primary tumors of EES occurred in the soft tissue and extremities (n = 20), abdomen and pelvis (n = 18), thorax (n = 14), paravertebral space (n = 8), head and neck (n = 6), and an unknown primary site (n = 4). Most primary tumors manifested as large and bulky soft-tissue masses (mean size, 9.0 cm; range, 1.3–23.0 cm), frequently invading adjacent organs (45.6%) and showed heterogeneous enhancement (73.7%), a well-defined (66.7%) margin, and partial necrosis/cystic degeneration (81.9%). Notably, 29 patients had metastatic disease detected at their initial diagnosis. The most frequent site of metastasis was lymph nodes (75.9%), followed by bone (31.0%), lung (20.7%), abdominal solid organs (13.8%), peritoneum (13.8%), pleura (6.9%), and brain (3.4%). Primary tumors of EES can occur anywhere and mostly manifest as large and bulky, soft-tissue masses. Lymph nodes are the most frequent metastasis sites.

담배 사용의 다차원적 영향: 행동 변화 중재 최적화

허지미 한국보건행정학회 2022 한국보건행정학회 학술대회 논문집 Vol.2022 No.2

Troubleshooting Arterial-Phase MR Images of Gadoxetate Disodium-Enhanced Liver

허지미,김소연,Benjamin M. Yeh,이승수,김경원,En-Haw Wu,Z. Jane Wang,Li-qin Zhao,Wei Chou Chang 대한영상의학회 2015 Korean Journal of Radiology Vol.16 No.6

Gadoxetate disodium is a widely used magnetic resonance (MR) contrast agent for liver MR imaging, and it provides both dynamic and hepatobiliary phase images. However, acquiring optimal arterial phase images at liver MR using gadoxetate disodium is more challenging than using conventional extracellular MR contrast agent because of the small volume administered, the gadolinium content of the agent, and the common occurrence of transient severe motion. In this article, we identify the challenges in obtaining high-quality arterial-phase images of gadoxetate disodium-enhanced liver MR imaging and present strategies for optimizing arterial-phase imaging based on the thorough review of recent research in this field.

Diffusion-Weighted MR Enterography to Monitor Bowel Inflammation after Medical Therapy in Crohn’s Disease: A Prospective Longitudinal Study

허지미,김경조,박성호,박소현,양석균,예병덕,박상형,한경화,김아영 대한영상의학회 2017 Korean Journal of Radiology Vol.18 No.1

Objective: To prospectively evaluate the performance of diffusion-weighted imaging (DWI) to monitor bowel inflammation after medical therapy for Crohn’s disease (CD). Materials and Methods: Before and following 1–2 years of medical therapy, between October 2012 and May 2015, 18 randomly selected adult CD patients (male:female, 13:5; mean age ± SD, 25.8 ± 7.9 years at the time of enrollment) prospectively underwent MR enterography (MRE) including DWI (b = 900 s/mm2) and ileocolonoscopy. Thirty-seven prospectively defined index lesions (one contiguous endoscopy-confirmed inflamed area chosen from each inflamed anatomical bowel segment; 1–4 index lesions per patient; median, 2 lesions) were assessed on pre- and post-treatment MRE and endoscopy. Visual assessment of treatment responses on DWI in 4 categories including complete remission and reduced, unchanged or increased inflammation, and measurements of changes in apparent diffusion coefficient (ΔADC), i.e., pre-treatment–post-treatment, were performed by 2 independent readers. Endoscopic findings and CD MRI activity index (CDMI) obtained using conventional MRE served as reference standards. Results: ΔADC significantly differed between improved (i.e., complete remission and reduced inflammation) and unimproved (i.e., unchanged or increased inflammation) lesions: mean ± SD (x 10-3 mm2/s) of -0.65 ± 0.58 vs. 0.06 ± 0.15 for reader 1 (p = 0.022) and -0.68 ± 0.56 vs. 0.10 ± 0.26 for reader 2 (p = 0.025). DWI accuracy for diagnosing complete remission or improved inflammation ranged from 76% (28/37) to 84% (31/37). A significant negative correlation was noted between ΔADC and ΔCDMI for both readers with correlation coefficients of -0.438 and -0.461, respectively (p < 0.05). Conclusion: DWI is potentially a feasible tool to monitor quantitatively and qualitatively bowel inflammation of CD after medical treatment.

Optimal Phase of Dynamic Computed Tomography for Reliable Size Measurement of Metastatic Neuroendocrine Tumors of the Liver: Comparison between Pre- and Post-Contrast Phases

허지미,Jisuk Park,Kyung Won Kim,김형중,이종석,이종화,정융기,Atul B. Shinagare,Nikhil H. Ramaiya 대한영상의학회 2018 Korean Journal of Radiology Vol.19 No.6

Objective: The reliability of size measurements of liver metastases from neuroendocrine tumors (NETs) on contrast-enhanced computed tomography (CT) phases made by different readers may be hampered due to transient, variable rim enhancement in arterial phase (AP) or portal venous phase (PVP) images. We aimed to assess the reliability of tumor size measurements in pre- and post-contrast scans. Materials and Methods: The study coordinator selected target lesions according to Response Evaluation Criteria in Solid Tumors 1.1 guidelines in 44 consecutive patients with pathologically confirmed NET liver metastases. Two blinded readers measured the longest diameters of target lesions on pre-contrast, AP, and PVP images twice with a 4-week interval. Interand intra-observer agreements were evaluated using Bland-Altman plots and 95% limit of agreement (LOA) calculations. Results: Of the 79 target lesions (approximate mean size of 3 cm), 45 showed rim enhancement. Inter-observer agreement assessed based on LOA was highest in pre-contrast CT images (-6.1–5.7 mm), followed by PVP (-7.9–7.1 mm) and AP (-8.5– 7.4 mm) images. Intra-observer agreement showed the same trend: -2.8–2.9 mm and -2.9–2.9 mm for readers 1 and 2, respectively, on pre-contrast CT, -2.8–2.9 mm and -3.0–3.2 mm, respectively, on PVP, and -3.2–4.2 mm and -3.4–3.2 mm, respectively, on AP images. Mean tumor diameters differed significantly among the phases in the following increasing order: pre-contrast CT, PVP, and AP images. Conclusion: There was better inter- and intra-observer agreement in size measurements of NET liver metastases on precontrast scans than on AP and PVP scans. Pre-contrast CT may be the optimal for measuring NET liver metastases if its accuracy is proven.

Test-retest repeatability of ultrasonographic shear wave elastography in a rat liver fibrosis model: toward a quantitative biomarker for preclinical trials

신용빈,허지미,함수정,조영철,최윤석,우동철,이정진,김경원 대한초음파의학회 2021 ULTRASONOGRAPHY Vol.40 No.1

Purpose: This study evaluated the test-retest repeatability and measurement variability of ultrasonographic shear wave elastography (SWE) for liver stiffness in a rat liver fibrosis model. Methods: In 31 Sprague-Dawley rats divided into three groups (high-dose, low-dose, and control), liver fibrosis was induced by intraperitoneal administration of thioacetamide for 8 weeks. A dedicated radiographer performed SWE to measure liver stiffness in kilopascals in two sessions at a 3-day interval. We calculated correlations between liver stiffness and histopathologic results, measurement variability in each session using coefficients of variation (CoVs) and interquartile/median (IQR/M), and test-retest repeatability between both sessions using the repeatability coefficient. Results: Different levels of liver fibrosis in each group were successfully induced in the animal model. The mean liver stiffness values were 8.88±1.48 kPa in the control group, 11.62±1.70 kPa in the low-dose group, and 11.91±1.73 kPa in the high-dose group. The correlation between collagen areas and liver stiffness values was moderate (r=0.6). In all groups, the second session yielded lower CoVs (i.e., more reliable results) for liver stiffness than the first session, suggesting a training effect for the operator. The mean IQR/M values were also lower in the second session than in the first session, which had four outliers (0.21 vs. 0.12, P<0.001). The test-retest repeatability coefficient was 3.75 kPa and decreased to 2.82 kPa after removing the four outliers. Conclusion: The use of ultrasonographic SWE was confirmed to be feasible and repeatable for evaluating liver fibrosis in preclinical trials. Operator training might reduce variability in liver stiffness measurements.

Recent Issues on Body Composition Imaging for Sarcopenia Evaluation

이고은,신용빈,허지미,성유섭,In-Seob Lee,Kwon-Ha Yoon,김경원 대한영상의학회 2019 Korean Journal of Radiology Vol.20 No.2

Recently, sarcopenia has garnered renewed interest. Sarcopenia is a disease characterized by decreased skeletal muscle mass and strength/function, which can impair the quality of life and increase physical disability, adverse metabolic effects, and mortality. Imaging tools for evaluating and diagnosing sarcopenia have developed rapidly. Radiologists should be aware of sarcopenia and its clinical implications. We review current knowledge about sarcopenia, its pathophysiological impact, and advantages and disadvantages of methods for evaluation of sarcopenia focusing on body composition imaging modalities such as whole-body dual-energy X-ray absorptiometry, CT, and MRI. Controversial issues are discussed, including the lack of consensus and standardization of the disease definition, imaging modality, measurement methods, and diagnostic cutoff points.