1.Comparison of Intracardiac Echocardiography Versus Transesophageal Echocardiography for Guidance During Transcatheter Aortic Valve Replacement
Sang-Hyup LEE ; Seunguk OH ; Young-Guk KO ; Yong-Joon LEE ; Seung-Jun LEE ; Sung-Jin HONG ; Chul-Min AHN ; Jung-Sun KIM ; Byeong-Keuk KIM ; Kyu-Yong KO ; Iksung CHO ; Chi Young SHIM ; Geu-Ru HONG ; Donghoon CHOI ; Myeong-Ki HONG
Korean Circulation Journal 2024;54(2):63-75
Background and Objectives:
Evidence regarding the efficacy and safety of intracardiac echocardiography (ICE) for guidance during transcatheter aortic valve replacement (TAVR) is limited. This study aimed to compare the clinical efficacy and safety of ICE versus transesophageal echocardiography (TEE) for guiding TAVR.
Methods:
This prospective cohort study included patients who underwent TAVR from August 18, 2015, to June 31, 2021. Eligible patients were stratified by echocardiographic modality (ICE or TEE) and anesthesia mode (monitored anesthesia care [MAC] or general anesthesia [GA]). Primary outcome was the 1-year composite of all-cause mortality, rehospitalization for cardiovascular cause, or stroke, according to the Valve Academic Research Consortium-3 (VARC-3) definition. Propensity score matching was performed, and study outcomes were analyzed for the matched cohorts.
Results:
Of the 359 eligible patients, 120 patients were matched for the ICE-MAC and TEEGA groups, respectively. The incidence of primary outcome was similar between matched groups (18.3% vs. 20.0%; adjusted hazard ratio, 0.94; 95% confidence interval [CI], 0.53– 1.68; p=0.843). ICE-MAC and TEE-GA also had similar incidences of moderate-to-severe paravalvular regurgitation (PVR) (4.2% vs. 5.0%; adjusted odds ratio, 0.83; 95% CI, 0.23– 2.82; p=0.758), new permanent pacemaker implantation, and VARC-3 types 2–4 bleeding.
Conclusions
ICE was comparable to TEE for guidance during TAVR for the composite clinical efficacy outcome, with similar incidences of moderate-to-severe PVR, new permanent pacemaker implantation, and major bleeding. These results suggest that ICE could be a safe and effective alternative echocardiographic modality to TEE for guiding TAVR.
2.Applications of Artificial Intelligence in Mammography from a Development and Validation Perspective
Journal of the Korean Radiological Society 2021;82(1):12-28
Mammography is the primary imaging modality for breast cancer detection; however, a high level of expertise is needed for its interpretation. To overcome this difficulty, artificial intelligence (AI) algorithms for breast cancer detection have recently been investigated. In this review, we describe the characteristics of AI algorithms compared to conventional computer-aided diagnosis software and share our thoughts on the best methods to develop and validate the algorithms. Additionally, several AI algorithms have introduced for triaging screening mammograms, breast density assessment, and prediction of breast cancer risk have been introduced.Finally, we emphasize the need for interest and guidance from radiologists regarding AI research in mammography, considering the possibility that AI will be introduced shortly into clinical practice.
3.The Effect of Adalimumab on Refractory Uveitis
Sang Hyup LEE ; Yong Sung YOO ; Hyun Sub OH
Journal of the Korean Ophthalmological Society 2020;61(7):746-754
Purpose:
To assess the efficacy and safety of Adalimumab (Humira®, AbbVie, Chicago, IL, USA) for repeated refractory uveitis during systemic steroid or immunosuppressive therapy.
Methods:
We retrospectively reviewed clinical records on 30 eyes of 18 patients with non-infectious refractory uveitis who underwent Adalimumab injection therapy from December 2017 to July 2019. The therapeutic effect was assessed based on intraocular inflammation grade, central macular thickness, and best corrected visual acuity, and the efficacy was assessed based on control of inflammation and macular edema, as well as corticosteroid sparing effects. The safety was assessed based on adverse events.
Results:
The mean duration of uveitis at baseline was 55.4 months (13-121 months) and the mean follow-up was 9.2 months (6-18 months). All 30 eyes of 18 patients stopped using systemic steroids and maintained clinical quiescence. Anterior chamber inflammation, vitreous inflammation, and best corrected visual acuity showed significant improvement, and there was no difference in central macular thickness. Uveitis recurred in 5 eyes, but 4 eyes showed controlled inflammation after single posterior sub-tenon steroid injection. One eye was controlled after methotrexate co-administration. Ulticaria (two patients) and injection- site reaction (one patient) were reported as adverse events.
Conclusions
Adalimumab is an effective treatment for decreasing inflammatory activity and reducing corticosteroid burden in refractory uveitis.
4.Distinguishing between Thymic Epithelial Tumors and Benign Cysts via Computed Tomography
Sang Hyup LEE ; Soon Ho YOON ; Ju Gang NAM ; Hyung Jin KIM ; Su Yeon AHN ; Hee Kyung KIM ; Hyun Ju LEE ; Hwan Hee LEE ; Gi Jeong CHEON ; Jin Mo GOO
Korean Journal of Radiology 2019;20(4):671-682
OBJECTIVE: To investigate whether computed tomography (CT) and fluorine-18-labeled fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) may be applied to distinguish thymic epithelial tumors (TETs) from benign cysts in the anterior mediastinum. MATERIALS AND METHODS: We included 262 consecutive patients with pathologically proven TETs and benign cysts 5 cm or smaller who underwent preoperative CT scans. In addition to conventional morphological and ancillary CT findings, the relationship between the lesion and the adjacent mediastinal pleura was evaluated qualitatively and quantitatively. Mean lesion attenuation was measured on CT images. The maximum standardized uptake value (SUVmax) was obtained with FDG-PET scans in 40 patients. CT predictors for TETs were identified with multivariate logistic regression analysis. For validation, we assessed the diagnostic accuracy and inter-observer agreement between four radiologists in a size-matched set of 24 cysts and 24 TETs using a receiver operating characteristic curve before and after being informed of the study findings. RESULTS: The multivariate analysis showed that post-contrast attenuation of 60 Hounsfield unit or higher (odds ratio [OR], 12.734; 95% confidence interval [CI], 2.506–64.705; p = 0.002) and the presence of protrusion from the mediastinal pleura (OR, 9.855; 95% CI, 1.749–55.535; p = 0.009) were the strongest CT predictors for TETs. SUVmax was significantly higher in TETs than in cysts (5.3 ± 2.4 vs. 1.1 ± 0.3; p < 0.001). After being informed of the study findings, the readers' area under the curve improved from 0.872–0.955 to 0.949–0.999 (p = 0.066–0.149). Inter-observer kappa values for protrusion were 0.630–0.941. CONCLUSION: Post-contrast CT attenuation, protrusion from the mediastinal pleura, and SUVmax were useful imaging features for distinguishing TETs from cysts in the anterior mediastinum.
Humans
;
Logistic Models
;
Mediastinum
;
Multivariate Analysis
;
Pleura
;
Positron-Emission Tomography
;
ROC Curve
;
Thymus Neoplasms
;
Tomography, X-Ray Computed
5.Fat Quantification in the Vertebral Body: Comparison of Modified Dixon Technique with Single-Voxel Magnetic Resonance Spectroscopy.
Sang Hyup LEE ; Hye Jin YOO ; Seung Man YU ; Sung Hwan HONG ; Ja Young CHOI ; Hee Dong CHAE
Korean Journal of Radiology 2019;20(1):126-133
OBJECTIVE: To compare the lumbar vertebral bone marrow fat-signal fractions obtained from six-echo modified Dixon sequence (6-echo m-Dixon) with those from single-voxel magnetic resonance spectroscopy (MRS) in patients with low back pain. MATERIALS AND METHODS: Vertebral bone marrow fat-signal fractions were quantified by 6-echo m-Dixon (repetition time [TR] = 7.2 ms, echo time (TE) = 1.21 ms, echo spacing = 1.1 ms, total imaging time = 50 seconds) and single-voxel MRS measurements in 25 targets (23 normal bone marrows, two focal lesions) from 24 patients. The point-resolved spectroscopy sequence was used for localized single-voxel MRS (TR = 3000 ms, TE = 35 ms, total scan time = 1 minute 42 seconds). A 2 × 2 × 1.5 cm³ voxel was placed within the normal L2 or L3 vertebral body, or other lesions including a compression fracture or metastasis. The bone marrow fat spectrum was characterized on the basis of the magnitude of measurable fat peaks and a priori knowledge of the chemical structure of triglycerides. The imaging-based fat-signal fraction results were then compared to the MRS-based results. RESULTS: There was a strong correlation between m-Dixon and MRS-based fat-signal fractions (slope = 0.86, R² = 0.88, p < 0.001). In Bland-Altman analysis, 92.0% (23/25) of the data points were within the limits of agreement. Bland-Altman plots revealed a slight but systematic error in the m-Dixon based fat-signal fraction, which showed a prevailing overestimation of small fat-signal fractions (< 20%) and underestimation of high fat-signal fractions (> 20%). CONCLUSION: Given its excellent agreement with single-voxel-MRS, 6-echo m-Dixon can be used for visual and quantitative evaluation of vertebral bone marrow fat in daily practice.
Bone Marrow
;
Evaluation Studies as Topic
;
Fractures, Compression
;
Humans
;
Low Back Pain
;
Magnetic Resonance Spectroscopy*
;
Neoplasm Metastasis
;
Spectrum Analysis
;
Spine
;
Triglycerides
6.Volumetric change of the latissimus dorsi muscle after immediate breast reconstruction with an extended latissimus dorsi musculocutaneous flap
Su Bong NAM ; Heung Chan OH ; Jae Yeon CHOI ; Seong Hwan BAE ; Ki Seok CHOO ; Hyun Yul KIM ; Sang Hyup LEE ; Jae Woo LEE
Archives of Plastic Surgery 2019;46(2):135-139
BACKGROUND: In immediate breast reconstruction using an extended latissimus dorsi musculocutaneous (eLDMC) flap, the volume of the flap decreases, which causes a secondary deformity of the breast shape. Since little research has investigated this decrease in muscle volume, the authors conducted an objective study to characterize the decrease in muscle volume after breast reconstruction using an eLDMC flap. METHODS: Research was conducted from October 2011 to November 2016. The subjects included 23 patients who underwent mastectomy due to breast cancer, received immediate reconstruction using an eLDMC flap without any adjuvant chemotherapy or radiotherapy, and received a computed tomography (CT) scan from days 7 to 10 after surgery and 6 to 8 months postoperatively. In 10 patients, an additional CT scan was conducted 18 months postoperatively. Axial CT scans were utilized to measure the volumetric change of the latissimus dorsi muscle during the follow-up period. RESULTS: In the 23 patients, an average decrease of 54.5% was observed in the latissimus dorsi muscle volume between the images obtained immediately postoperatively and the scans obtained 6 to 8 months after surgery. Ten patients showed an average additional decrease of 11.9% from 6–8 months to 18 months after surgery. CONCLUSIONS: We studied changes in the volume of the latissimus dorsi muscle after surgery using an eLDMC flap performed after a mastectomy without adjuvant chemotherapy or radiotherapy. In this study, we found that immediate breast reconstruction using a latissimus dorsi muscle flap led to a decrease in muscle volume of up to 50%.
Breast Neoplasms
;
Breast
;
Chemotherapy, Adjuvant
;
Congenital Abnormalities
;
Female
;
Follow-Up Studies
;
Humans
;
Mammaplasty
;
Mastectomy
;
Myocutaneous Flap
;
Radiotherapy
;
Superficial Back Muscles
;
Tomography, X-Ray Computed
7.Complication Following Ultrasound-Guided High-Intensity Focused Ultrasound for the Treatment of Uterine Adenomyosis: Case Report of CT Imaging Features
Sang Hyup HONG ; Gil Sun HONG ; Choong Wook LEE ; Gi Hong KIM
Journal of the Korean Radiological Society 2019;80(3):579-584
High intensity focused ultrasound (HIFU) is a non-surgical and non-invasive treatment option in patients with uterine myoma and adenomyosis. As the use of HIFU increases in the clinical practice, it is important to be aware of imaging findings related to ultrasound (US)-guided HIFU ablation and its potential complications. However, there are few reports on the imaging findings regarding complications of US-guided HIFU ablation. Here, we report a case of acute complication after US-guided HIFU ablation, surgically confirmed as thermal injury with necrosis of skin, subcutaneous tissue, anterior abdominal wall muscles, peritoneum and uterus.
8.A Rare Case of Granulomatosis with Polyangiitis-Related Periaortitis at the Ascending Aorta
Sang Hyup HONG ; Gil Sun HONG ; Choong Wook LEE ; Gi Hong KIM
Journal of the Korean Radiological Society 2019;80(3):537-542
Acute aortic syndrome including intramural hematoma is a life-threatening disease encountered in the emergency department with high in-hospital mortality even when a timely diagnosis is made. Therefore, accurate differential diagnosis of acute aortic syndrome and its mimics is important to determine the patient's treatment plan. Until now, a few pathologic diseases mimicking aortic intramural hematoma such as periaortic lymphoma and immunoglobulin G4-elated periaoritis have been reported. Here, we report a rare case of granulomatosis with polyangiitis-related periaortitis misdiagnosed as aortic intramural hematoma presenting to the emergency department with chest pain and similar radiologic findings.
9.Immunoglobulin G4-Related Disease Presenting with Isolated, Intractable Trigeminal Neuralgia
Sang Hyup JIN ; Sung Eun LEE ; Mi Il KANG ; Jee Hyun KIM
Journal of the Korean Neurological Association 2018;36(3):231-234
Immunoglobulin G4-related disease (IgG4-RD) is an immune-mediated systemic condition affecting diverse organs which lately has been increasingly recognized. A 40-year-old male presents intractable trigeminal neuralgia lasting more than a year even with numerous pain medication, which lead further evaluation. The infiltrative lesion was found involving left pterygopalatine fossa where maxillary nerve locates. We report a case of IgG4-RD with a sole manifestation of intractable unilateral trigeminal neuralgia which was improved by steroid treatment.
Adult
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Facial Pain
;
Humans
;
Immunoglobulins
;
Male
;
Maxillary Nerve
;
Pterygopalatine Fossa
;
Trigeminal Neuralgia
10.Use of Iterative Reconstruction and a Small Contrast Volume in Rabbit Kidney CT: Comparison with Conventional Protocol
Rihyeon KIM ; Sang Youn KIM ; Jeong Yeon CHO ; Joongyub LEE ; Seung Hyup KIM
Journal of the Korean Radiological Society 2018;79(2):77-87
PURPOSE:
To investigate the quality of rabbit kidney computed tomography (CT) images obtained using a small contrast volume and iterative reconstruction (IR).
MATERIALS AND METHODS:
Twenty sedated rabbits were used. Four milliliters of contrast material and the IR technique were used for the study group. In the control group, 6 mL of contrast and the filtered back projection (FBP) technique were used. The image quality was evaluated by two radiologists in consensus. For qualitative image assessment, the sharpness, noise, texture, and streak artifacts were rated. For quantitative analysis, the CT attenuation values, image noise, signal-to-noise ratios (SNR), contrast-to-noise ratios (CNR), and figures of merit (FOM) were calculated.
RESULTS:
Images obtained from the study group were sharper and contained less noise and fewer streak artifacts (all, p < 0.05) compared to those obtained from the control group. However, the texture of images from the study group was worse (p < 0.05). Although the CT attenuation values were comparable between the study and control groups, the image noise was considerably lower for the study group than that for the corresponding control group (all, p < 0.05). Thus, the SNR, CNR, and FOM were higher in the study group (all, p < 0.05) than in the control group.
CONCLUSION
The use of the IR technique and a small volume of contrast material yielded CT images with better qualities compared to those obtained using the FBP technique and conventional contrast volume in a rabbit model.

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