• Journal of the Korean Society of Radiology
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• v.17 no.3
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• pp.423-431
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• 2023

The purpose of this study is to analyze the factors affecting the classification of the severity of contrast media side effects based on the patient's body information using artificial intelligence techniques to be used as basic data to reduce the degree of contrast medium side effects. The data used in this study were 606 examiners who had no contrast medium side effects in the past history survey among 1,235 cases of contrast medium side effects among 58,000 CT scans performed at a general hospital in Seoul. The total data is 606, of which 70% was used as a training set and the remaining 30% was used as a test set for validation. Age, BMI(Body Mass Index), GFR(Glomerular Filtration Rate), BUN(Blood Urea Nitrogen), GGT(Gamma Glutamyl Transgerase), AST(Aspartate Amino Transferase,), and ALT(Alanine Amiono Transferase) features were used as independent variables, and contrast media severity was used as a target variable. AUC(Area under curve), CA(Classification Accuracy), F1, Precision, and Recall were identified through AdaBoost, Tree, Neural network, SVM, and Random foest algorithm. AdaBoost and Random Forest show the highest evaluation index in the classification prediction algorithm. The largest factors in the predictions of all models were GFR, BMI, and GGT. It was found that the difference in the amount of contrast media injected according to renal filtration function and obesity, and the presence or absence of metabolic syndrome affected the severity of contrast medium side effects.

• Journal of Veterinary Science
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• v.21 no.4
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• pp.55.1-55.11
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• 2020

Background: Computed tomography urography (CTU), based on the excretion of contrast medium after its injection, allows visualization of the renal parenchyma and the renal collecting system. Objectives: To determine the optimal contrast medium dose allocation ratio to apply in split-bolus CTU in dogs. Methods: This prospective, experimental, exploratory study used 8 beagles. In 3-phase CTU, unenhanced-, nephrographic-, and excretory-phase images were obtained with a single injection of 600 mg iodine/kg iohexol. In split-bolus CTU, two different contrast medium allocation ratios (30% and 70% for split CTU 1; 50% and 50% for split CTU 2) were used. Unenhanced phase image and a synchronous nephrographic-excretory phase image were acquired. Results: Although the attenuation of the renal parenchyma was significantly lower when using both split CTUs than the 3-phase CTU, based on qualitative evaluation, the visualization score of the renal parenchyma of split CTU 1 was as high as that of the 3-phase CTU, whereas the split CTU 2 score was significantly lower than those of the two others. Artifacts were not apparent, regardless of CTU protocol. The diameter and opacification of the ureter in both split CTUs were not significantly different from those using 3-phase CTU. Conclusions: Split-bolus CTU with a contrast medium allocation ratio of 30% and 70% is feasible for evaluating the urinary system and allows sufficient enhancement of the renal parenchyma and appropriate distention and opacification of the ureter, with similar image quality to 3-phase CTU in healthy dogs. Split-bolus CTU has the advantages of reducing radiation exposure and the number of CT images needed for interpretation.

• Korean Journal of Digital Imaging in Medicine
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• v.9 no.1
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• pp.17-19
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• 2007

This study applies in case of operating an exam using by the contrast order or inputting an order of a contrast media the exam of Radiology Department. It is developed for helping decision making as regards a process of an exam from reading the creatinine value automatically linked with Laboratory Information System. It can be confirmed by real-time information; therefore, the creditability of the information is able to be improved. We will create the base for Patient Monitoring System with the data from the side effect of the creatinine value and allergies. Decision Support System minimize the inconvenience and the riskiness of the given contrast medium for CT tests. We would like to improve medical services by providing a standard circumstance where patients are able to run tests safely and comfortably.

• Korean Journal of Veterinary Research
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• v.61 no.2
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• pp.17.1-17.4
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• 2021

A seven-year-old, castrated male, Korean domestic shorthair cat was referred because of a kidney abnormality. Radiography revealed left renal agenesis and right kidney enlargement. Ultrasonography and computed tomography (CT) showed amorphous calcified materials in a cyst-like lesion of the right kidney. In the excretory phase of the CT images, the lesion was opacified with contrast materials, indicating communication with the collecting system. Based on these findings, the cat was diagnosed with a calyceal diverticulum. A calyceal diverticulum may cause various clinical symptoms related to the urinary system. The excretory phase of CT is useful for diagnosing a calyceal diverticulum.

• Journal of the Korean Society of Radiology
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• v.9 no.1
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• pp.9-16
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• 2015

The purpose of this study is finding optimum contrast medium quantity during abdominal CT using dual energy technique. The study subjects are 30 patients who had received general single energy abdominal CT and received double energy technique follow-up abdominal CT. dual energy technique abdominal CT images were obtained after setting contrast medium quantities at 30%, 40%, 50%, 60% and 70% of contrast medium quantity at the time of single energy technique. Then the contrast enhancement (Hounsfield Unit; HU) was estimated by setting-up the regions of interest at aorta, inferior vena cava, hepatic portal vein and hepatic parenchymal. The obtained values were compared to the values of the same parts measured during single energy technique abdominal CT. The results of the study were as following. The 60% set up group had HU in aorta : $210.80{\pm}13.609$, IVC : $190.40{\pm}25.215$, hepatic portal vein : $198.40{\pm}21.232$ and hepatic parenchymal : $119.20{\pm}7.98$, The single energy abdomianl CT images had HU in aorta : $205.40{\pm}16.426$, IVC : $188.20{\pm}21.476$, hepatic portal vein : $195.40{\pm}22.744$ and hepatic parenchymal : $121.00{\pm}6.595$. Therefore, it is possible to obtain contrast enhancement by dual energy technique abdominal CT similar to the same by single energy technique abdominal CT by setting-up the quantity of contrast medium at 60% of contrast medium at the time of single energy technique abdominal CT. Based on the result of this study, it is possible to decrease existing quantity of contrast medium by _% and the injection velocity can be also decreased. Accordingly, it is believed that the result of study would be quite useful for patients who have renal function disorder, weak vein or side effect of contrast medium in the past.

• Journal of the Korea Safety Management & Science
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• v.16 no.4
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• pp.427-431
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• 2014

The purpose of this study is to monitor the current adverse reactions in administering CT contrast agents at general hospitals and also to suggest the practical guidelines to minimize the risk and to show the successful patient management. At four Dajeon city general hospitals, the contrast agents were administered in 646,828 cases and the overall prevalence of adverse reactions was 4,110 cases from January 2010 to December 2013. However, we excluded the two hospitals' 3,658 cases because the patients' data was inadequate. Consequently, the case surveys on the rest of 452 cases have been studied and submitted. After comparing the patients with a control group, we evaluated that the key factors of the adverse reactions were the gender and age difference of the patients, the examination period, the examination method, the quantity and administrating speed of the contrast agents. Even though the four general hospitals have their own management systems on adverse reactions, but their systems were not satisfying. To improve the quality of the management systems and to investigate further cases, some hospital administration procedures on the subject should be systemized and general hospitals should follow the recommended procedures. Moreover, the existing three-year-term evaluation should not only judge the adverse reaction management but also conclude some details on the sub criteria of the evaluation. The details on the sub criteria include the contrast agent characters, the quantity and administrating speed of the drug, the incidents' occurred time, an anamnesis; a case history, the medical history of the patients and the reaction occurring body parts, and the examination title. The details of the medical examiners are also added to the sub criteria.

• Journal of Biomedical Engineering Research
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• v.29 no.1
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• pp.66-72
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• 2008

The major risk associated with the use of automated power injectors is the well known complication of contrast material extravasation at the injection site. Automated injection of computed tomography (CT) contrast media can produce the compartment syndrome. The purpose of this study was to assess the ability of this device during clinically important episodes of extravasation. The extravasation detection accessory (EDA) system was composed of a strain gage, an amplifier and a computer based system. A strain gage pliable adhesive patch was applied to the skin aver the intravenous catheter and the catheter was connected to the power injector with a cable to monitor the resolution data. If the programmed monitoring, which was developed with MS Visual C++, at the extravasation occurred, then the injection was interrupted the auto injector. CT was used to demonstrate the clinically important extravasation. This study was a prospective, observational study in which the EDA system was used to monitor the automated mechanical injection of contrast material in 7 dogs. There were two true-positive cases (range of extravasation volumes: $18{\sim}22ml$), twenty three true-negative cases, three false-positive cases and no false-negative cases. The EDA system had a sensitivity of 100% and a specificity of 88% for the detection of clinically important extravasation. The EDA system had good sensitivity for the detection of clinically important extravasation and the EDA system has the clinical potential for the early detection of extravasation of the contrast medium that is administered with power injectors. The EDA system is easy to use safe and accurate for the monitoring extravasation of the intravenous injections, and this system may prove especially useful in CT applications.

• Journal of International Society for Simulation Surgery
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• v.1 no.1
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• pp.37-40
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• 2014

Purpose For living donor liver transplantation, liver segmentation is difficult due to the variability of its shape across patients and similarity of the density of neighbor organs such as heart, stomach, kidney, and spleen. In this paper, we propose an automatic segmentation of the liver using multi-planar anatomy and deformable surface model in portal phase of abdominal contrast-enhanced CT images. Method Our method is composed of four main steps. First, the optimal liver volume is extracted by positional information of pelvis and rib and by separating lungs and heart from CT images. Second, anisotropic diffusing filtering and adaptive thresholding are used to segment the initial liver volume. Third, morphological opening and connected component labeling are applied to multiple planes for removing neighbor organs. Finally, deformable surface model and probability summation map are performed to refine a posterior liver surface and missing left robe in previous step. Results All experimental datasets were acquired on ten living donors using a SIEMENS CT system. Each image had a matrix size of $512{\times}512$ pixels with in-plane resolutions ranging from 0.54 to 0.70 mm. The slice spacing was 2.0 mm and the number of images per scan ranged from 136 to 229. For accuracy evaluation, the average symmetric surface distance (ASD) and the volume overlap error (VE) between automatic segmentation and manual segmentation by two radiologists are calculated. The ASD was $0.26{\pm}0.12mm$ for manual1 versus automatic and $0.24{\pm}0.09mm$ for manual2 versus automatic while that of inter-radiologists was $0.23{\pm}0.05mm$. The VE was $0.86{\pm}0.45%$ for manual1 versus automatic and $0.73{\pm}0.33%$ for manaual2 versus automatic while that of inter-radiologist was $0.76{\pm}0.21%$. Conclusion Our method can be used for the liver volumetry for the pre-surgery planning of living donor liver transplantation.

• Journal of Korean Neurosurgical Society
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• v.50 no.1
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• pp.45-47
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• 2011

Abnormal contrast enhancement on brain computed tomography (CT) scan after diagnostic or interventional angiography is not rare, and has known to be induced by temporary blood-brain barrier (BBB) disruption from contrast media. Furthermore, it has been regarded as clinically subtle, but reported to have no symptom or mild transient symptoms. However, we recently experienced two cases of serious BBB disruption during the acute period after coiling of an unruptured intracranial aneurysm. One patient presented with an unruptured paraclinoid internal carotid artery (ICA) aneurysm on the right and the other with an unruptured right supraclinoid ICA aneurysm. Both patients showed similar findings on immediate postembolization CT scan and clinical courses after coiling. Typical radiological, clinical characteristics of BBB disruption were described. In addition, the role of immediate postembolization CT scan are also discussed.

• Progress in Medical Physics
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• v.24 no.1
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• pp.68-75
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• 2013

The purpose of this research is to compare and analyze $SUV_{LBM}$-maximum of normal regions using VOI (the volume of interest) in order to enhance the diagnostic level in whole body images of PET/CT and PET/MRI for 26 health check-up participants. In particular, we try to set up $SUV_{LBM}$-maximum data that can be used in synchronous evaluation for PET/CT and PET/MRI without contrast media. The evaluation of $SUV_{LBM}$-maximum for normal regions of whole body PET/CT and whole body PET/MRI shows that the image of PET/MRI differs very significantly from the reference image of PET/CT (p<0.0001). However, they exhibit high correlations in view of statistics (R>0.8). From this research, we suggest that the decision in the evaluation of $SUV_{LBM}$-maximum for PET/MRI should be made with the reduction of about 26.3%, while one should decide with the reduction of about 29.3% when the contrast media is used. It is helpful to interpret all image of PET/CT and PET/MRI using $SUV_{LBM}$-maximum for convenience and efficiency.