• The Korean Journal of Nuclear Medicine
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• v.39 no.2
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• pp.118-123
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• 2005

Positron emission tomography (PET) serves as a gold standard for noninvasive in vivo measurement of myocardial blood flow (MBF) and coronary flow reserve (CFR). CFR can be defined as the ratio of maximally vasodilated MBF over its basal flow. It is an important parameter for the evaluation of functional severity of coronary stenosis and prognositification in various diseases such as dilated cardiomyopathy. $^{13}NH_3,\;H_2^{15}O,\;^{82}Rb$ are widely used radiopharmaceuticals for measuring MBF and CFR, This review introduces imaging techniques and its clinical utility. Cardiac application or PET and PET/CT is expected to be increased in near future.

• Korean Journal of Radiology
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• v.22 no.3
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• pp.334-343
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• 2021

Objective: We aimed to develop a prediction model for diagnosing severe aortic stenosis (AS) using computed tomography (CT) radiomics features of aortic valve calcium (AVC) and machine learning (ML) algorithms. Materials and Methods: We retrospectively enrolled 408 patients who underwent cardiac CT between March 2010 and August 2017 and had echocardiographic examinations (240 patients with severe AS on echocardiography [the severe AS group] and 168 patients without severe AS [the non-severe AS group]). Data were divided into a training set (312 patients) and a validation set (96 patients). Using non-contrast-enhanced cardiac CT scans, AVC was segmented, and 128 radiomics features for AVC were extracted. After feature selection was performed with three ML algorithms (least absolute shrinkage and selection operator [LASSO], random forests [RFs], and eXtreme Gradient Boosting [XGBoost]), model classifiers for diagnosing severe AS on echocardiography were developed in combination with three different model classifier methods (logistic regression, RF, and XGBoost). The performance (c-index) of each radiomics prediction model was compared with predictions based on AVC volume and score. Results: The radiomics scores derived from LASSO were significantly different between the severe AS and non-severe AS groups in the validation set (median, 1.563 vs. 0.197, respectively, p < 0.001). A radiomics prediction model based on feature selection by LASSO + model classifier by XGBoost showed the highest c-index of 0.921 (95% confidence interval [CI], 0.869-0.973) in the validation set. Compared to prediction models based on AVC volume and score (c-indexes of 0.894 [95% CI, 0.815-0.948] and 0.899 [95% CI, 0.820-0.951], respectively), eight and three of the nine radiomics prediction models showed higher discrimination abilities for severe AS. However, the differences were not statistically significant (p > 0.05 for all). Conclusion: Models based on the radiomics features of AVC and ML algorithms may perform well for diagnosing severe AS, but the added value compared to AVC volume and score should be investigated further.

• Journal of Veterinary Clinics
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• v.25 no.3
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• pp.187-191
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• 2008

A 7-year-old, intact female Yorkshire terrier dog was presented for coughing, anorexia, chest pain and dyspnea. Right lateral thoracic radiograph demonstrated a large mass shape on the heart base with decreased cardiac silhouette and severe right deviation of the trachea with the heart shifted to the left thoracic wall was observed on the ventrodorsal thoracic projection. Echocardiographic examination revealed a large rounded mass compressing left atrium around the heart base without signs of pericardial effusion. On computed tomographic (CT) findings, sagittal CT images depicted the possibility of cranial vena caval invasion and heart base involvement of the mass associated with biatrial compression. Dorsal CT image revealed the right deviation of trachea due to the heart base mass and markedly shrunk lung space was detected on the transverse CT image. Because the dog suddenly had died during the recovery from anesthesia after finishing CT scan, necropsy was performed. On gross findings, a large and lobulated mass was located at the base of the heart. A poorly-demarcated, infiltrative, multilobulated tumor composed of polyhedral cells in solid cellular sheets was confirmed based on histopathologic examination. This dog was diagnosed as a chemodectoma. This case report describes the clinical findings, diagnostic consistency of thoracic radiography, echocardiography and CT, and histopathologic confirmation in a spontaneously occurring chemodectoma with a Yorkshire terrier dog.

• Korean Journal of Radiology
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• v.19 no.6
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• pp.1031-1041
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• 2018

Objective: To compare image quality and radiation dose of high-pitch dual-source spiral cardiothoracic computed tomography (CT) between non-electrocardiography (ECG)-synchronized and prospectively ECG-triggered data acquisitions in young children with congenital heart disease. Materials and Methods: Eighty-six children (${\leq}3$ years) with congenital heart disease who underwent high-pitch dual-source spiral cardiothoracic CT were included in this retrospective study. They were divided into two groups (n = 43 for each; group 1 with non-ECG-synchronization and group 2 with prospective ECG triggering). Patient-related parameters, radiation dose, and image quality were compared between the two groups. Results: There were no significant differences in patient-related parameters including age, cross-sectional area, body density, and water-equivalent area between the two groups (p > 0.05). Regarding radiation dose parameters, only volume CT dose index values were significantly different between group 1 ($1.13{\pm}0.09mGy$) and group 2 ($1.07{\pm}0.12mGy$, p < 0.02). Among image quality parameters, significantly higher image noise ($3.8{\pm}0.7$ Hounsfield units [HU] vs. $3.3{\pm}0.6HU$, p < 0.001), significantly lower signal-to-noise ratio ($105.0{\pm}28.9$ vs. $134.1{\pm}44.4$, p = 0.001) and contrast-to-noise ratio ($84.5{\pm}27.2$ vs. $110.1{\pm}43.2$, p = 0.002), and significantly less diaphragm motion artifacts ($3.8{\pm}0.5$ vs. $3.7{\pm}0.4$, p < 0.04) were found in group 1 compared with group 2. Image quality grades of cardiac structures, coronary arteries, ascending aorta, pulmonary trunk, lung markings, and chest wall showed no significant difference between groups (p > 0.05). Conclusion: In high-pitch dual-source spiral pediatric cardiothoracic CT, additional ECG triggering does not substantially reduce motion artifacts in young children with congenital heart disease.

• The Journal of the Korea Contents Association
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• v.11 no.5
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• pp.252-259
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• 2011

To identify the effects of the application of the adaptive statistical iterative reconstruction (ASIR) technique in combination with the other two factors of body mass Index (BMI) and tube potential on radiation dose in cardiac CT. The patient receiving operation the cardiac CT examination was divided four groups into according to kVp.[A group(n=20), Non-ASIR, BMI < 25, 100 kVp; B group(n=20), Non-ASIR, BMI > 25, 120 kVp; C group(n=20), 40% ASIR BMI < 25, 100 kVp; D group(n=20), 40% ASIR, BMI > 25, 120 kVp] After setting up the region of interest in the main artery central part and right coronary artery and left anterior descending artery, the CT number was measured and an average and standard deviation were analyzed. There were A group and the difference which the image noise notes statistically between C. And A group was high so that the noise could note than C group (group A, 494 ${\pm}$ 32 HU; group C, 482 ${\pm}$ 48 HU: P<0.05) In addition, there were B group and the difference noted statistically between D. And B group was high so that the noise could note than D group (group B, 510 ${\pm}$ 45 HU; group D, 480 ${\pm}$ 82 HU: P<0.05). In the qualitative analysis of an image, there was no difference (p>0.05) which a group, B group, C group, and D as to average, A group 4.13${\pm}$0.2, B group 4.18${\pm}$0.1, and C group 4.1${\pm}$0.2 and D group note statistically altogether with 4.15${\pm}$0.1 as a result of making the clinical evaluation according to the coronary artery segments. And the inappropriate image was shown to the diagnosis in all groups. As to the radiation dose, a group 8.6${\pm}$0.9 and B group 14.9${\pm}$0.4 and C group 5.8${\pm}$0.5 and D group are 10.1${\pm}$0.6 mSv.

• Journal of the Korean Society of Radiology
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• v.81 no.2
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• pp.324-336
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• 2020

Cardiovascular calcifications can occur in various cardiovascular diseases and can serve as a biomarker for cardiovascular event prediction. Advances in CT have enabled evaluation of calcifications in cardiovascular structures not only on ECG-gated CT but also on non-ECG-gated CT. Therefore, many studies have been conducted on the clinical relevance of cardiovascular calcifications in patients. In this study, we divided cardiovascular calcifications into three classes, i.e., coronary artery, thoracic aorta, and cardiac valve calcifications, which are closely associated with cardiovascular events. Further, we briefly described pericardial calcifications, which can be found incidentally. Since the start of lung cancer screening in Korea in the second half of 2019, the number of non-enhanced, non-ECG-gated, low-dose chest CT has been increasing, and the number of incidentally found cardiovascular calcifications has also been increasing. Therefore, understanding the relevance of cardiovascular calcifications on non-enhanced, non-ECG-gated, low-dose chest CT and their proper reporting are important for radiologists.

• Journal of Chest Surgery
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• v.33 no.10
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• pp.827-829
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• 2000

We experienced a case of partial anomalous pulmonary venous return from righ lung to inferior vena cava, which combined with Scimitar sign in 18 years old female patient. Diagnostic procedures were simple chest x-ray chest CT, and cardiac catheterization. We redirected the anomalous venous flow from inferior vena cava to left atrium through the intracardiac tunnel which was made with autologous pericardium. Postoperative course was not eventful.

• Journal of Pharmacopuncture
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• v.10 no.3
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• pp.143-147
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• 2007

Objective To derive further studies evaluating the effectiveness of Cultured Wild Ginseng Pharmacopuncture (CWGP) Therapy on squamous cell carcinoma as a first line. Methods Three cycles (4 weeks/cycle) of CWGP were administered as a dosage of 10 ml per day. Patient was diagnosed with stage IIIB squamous cell carcinoma and refused all therapy of conventional medicine because of old age and cardiac invasion of tumor. Intensive treatment of CWGP for 3 cycles was done on the patient. Computed Topography (CT) was performed to evaluate the therapeutic efficacy. Results After the intravenous infusion of 2 cycles of CWGP, chest CT revealed the mass size and pleural invasion sustained stable disease. After the point injection of 1 cycle of CWGP, chest CT revealed progressive disease. The disease free survival rate was 1 month. Conclusion This case may provide us the possibility that CWGP offers potential benefits for patients with squamous cell lung carcinoma. But this is a single case study and further case-series research should be compensated.

• Journal of Chest Surgery
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• v.43 no.2
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• pp.194-198
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• 2010

Intramural hematoma of the aorta (IMH) is the precursor or a variant of a classic aortic dissection where hemorrhage occurs within the aorta wall in the absence of an initial intimal tear. IMH has a high rate of mortality and morbidity. The optimal therapy for IMH is uncertain, yet the involvement of the ascending aorta is usually considered as an indication for surgery due to the associated risk of rupture or cardiac tamponade. We report here on a case of a 71-year-old man who presented with syncope. Because of misdiagnosis, he underwent computed tomography (CT) after 5 hrs from arriving to the ER. Computed tomography of the aorta revealed intramural hematoma of the ascending aorta with cardiac tamponade. He also had vascular complications such as acute renal failure and visceral ischemia. We performed emergency graft replacement of the total arch and ascending aorta. He was discharged without complication on postoperative day 14.

• Journal of the Korean Society of Radiology
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• v.82 no.4
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• pp.982-987
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• 2021

The coronary sinus (CS) is the venous drainage system of the heart. CS ostium atresia is a rarely seen cardiac malformation. Congenital atresia of the CS is usually found together with persistent left superior vena cava (LSVC) and other cardiac malformations. However, isolated congenital atresia of the CS is very rare. We present a rare case of isolated congenital atresia of the CS connecting the left atrium and coronary veins without persistent LSVC in a 58-year-old female.