Purpose: To survey the perception, knowledge, wishes, and expectations of Korean radiology residents regarding artificial intelligence (AI) in radiology. Materials and Methods: From June 4th to 7th, 2019, questionnaires comprising 19 questions related to AI were distributed to 113 radiology residents. Results were analyzed based on factors such as the year of residency and location and number of beds of the hospital. Results: A total of 101 (89.4%) residents filled out the questionnaire. Fifty (49.5%) respondents had studied AI harder than the average while 68 (67.3%) had a similar or higher understanding of AI than the average. In addition, the self-evaluation and knowledge level of AI were significantly higher for radiology residents at hospitals located in Seoul and Gyeonggi-do compared to radiology residents at hospitals located in other regions. Furthermore, the self-evaluation and knowledge level of AI were significantly lower in junior residents than in residents in the 4th year of training. Of the 101 respondents, only 16 (15.8%) had experiences in AI-related study while 91 (90%) were willing to participate in AI-related study in the future. Conclusion Organizational efforts through a radiology society would be needed to meet the need of radiology trainees for AI education and to promote the role of radiologists more adequately in the era of medical AI.

PURPOSE: Reducing preoperative fasting time showed positive effects in several studies, and current guidelines suggest use of a preoperative oral carbohydrate-rich solution before elective surgeries. For elective colectomy procedures, some surgeons favor two-day bowel preparation with diet restriction and administration of laxatives. Aside from patients experiencing the discomfort of nil per os (NPO), there are reported benefits regarding intake of liquids until at least two hours prior to surgery, including decrease in insulin resistance, without additional postoperative surgical complications. The aim of this study is to show the benefits of administration of oral rehydration solution (ORS) two hours prior to surgery for patients undergoing elective colectomy, particularly postoperative insulin resistance. METHODS: This is a randomized controlled trial. All patients undergoing elective colectomy were included and randomized to the control arm or treatment arm. The control arm consisted of the standard bowel preparation and one day of NPO, while the treatment arm consisted of the standard bowel preparation and allowing intake of carbohydrate-rich ORS until 2 hours before surgery. The insulin, glucose, cortisol, and triglyceride levels were determined immediately after induction, 6 hours, 24 hours, and 48 hours post-op, and compared. The homeostatic model assessment-insulin resistance, insulin, glucose, cortisol, and triglyceride levels were determined and compared between the two groups. Anxiety and postoperative complications were monitored and assessed as well. RESULTS: There was less insulin resistance in patients who received ORS 2 hours prior to surgery. Insulin, glucose, cortisol, and triglyceride levels were lower in the treatment group compared to the control group. Taking ORS 1 day prior and until 2 hours before surgery decreased anxiety and discomfort, and alleviated hunger. CONCLUSION: Regarding complications, there was no difference in the incidence of aspiration and postoperative complications. There were fewer wound complications and incidence of paralytic ileus in the treatment group.
Anxiety ; Arm ; Colectomy* ; Diet ; Fasting ; Fluid Therapy ; Glucose ; Humans ; Hunger ; Hydrocortisone ; Incidence ; Insulin Resistance* ; Insulin* ; Intestinal Pseudo-Obstruction ; Laxatives ; Postoperative Complications ; Triglycerides ; Wounds and Injuries

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.

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.

OBJECTIVE: To describe CT and clinical findings of pulmonary artery intimal sarcoma (PAIS) compared with those of pulmonary thromboembolism (PTE), to investigate MRI and positron emission tomography (PET)-CT findings of PAIS, and to evaluate the effect of delayed diagnosis of PAIS on survival outcomes. MATERIALS AND METHODS: Twenty-six patients with PAIS were retrospectively identified and matched for sex, with patients with PTE at a ratio of 1:2. CT and clinical findings of the two groups were compared using Student's t test or chi-square test. The effect of delayed diagnosis on survival was investigated using Kaplan-Meier analysis. RESULTS: The most common tumor pattern in PAIS was tumoral impaction. Heterogeneous attenuation, wall eclipse signs, intratumoral vessels, acute interphase angles, single location, presence of lung ischemia, and central location were significantly more common in PAIS than in PTE (all p < 0.01). Levels of D-dimers and brain natriuretic peptide were lower in PAIS than in PTE (p < 0.05). In three patients of PAIS, long inversion time sequence MRI showed intermingled dark signal intensity foci suggestive of intermingled thrombi. All nine patients who had undergone PET-CT displayed hypermetabolism. Diagnosis was delayed in 42.3% of the PAIS patients and those patients had a significantly shorter overall survival than patients whose diagnosis was not delayed (p < 0.05). CONCLUSION: The characteristic CT and clinical findings of PAIS may help achieve early diagnosis of PAIS and make better survival outcomes of patients. MRI and PET-CT can be used as second-line imaging modalities and could help distinguish PAIS from PTE and to plan clinical management.
Delayed Diagnosis ; Diagnosis ; Early Diagnosis ; Humans ; Interphase ; Ischemia ; Kaplan-Meier Estimate ; Lung ; Magnetic Resonance Imaging ; Natriuretic Peptide, Brain ; Positron-Emission Tomography ; Pulmonary Artery* ; Pulmonary Embolism ; Retrospective Studies ; Sarcoma* ; Thromboembolism*

BACKGROUND: The computer-assisted continuous infusion (CACI) system was developed to more rapidly attain and to maintain stable effect-site fentanyl concentrations as compared with the intermittent injection method. The CACI system allows the anesthesiologist to control effect-site fentanyl concentrations during various surgical stimuli during cardiac anesthesia. This system can rapidly control the depth of anesthesia and compensate for the disadvantages of IV anesthesia. Early patient recovery also enables early tracheal extubation, which is an important component of the "fast track" cardiac surgery pathway. In this study, the use of a target-controlled infusion of low-dose propofol was combined with the target-controlled infusion of fentanyl for patients undergoing coronary artery bypass graft surgery. The purpose of this study was to evaluate the proper effect-site concentration of fentanyl for the tracheal intubation of patients undergoing coronary artery bypass graft surgery. METHODS: Fifty patients scheduled for elective coronary artery bypass graft surgery were included, and randomly allocated to group L (effect-site fentanyl concentration = 5 ng/ml, n = 25) or group H (effect-site fentanyl concentration = 7.5 ng/ml, n = 25). Anesthesia was induced and maintained by the computer-controlled infusions of propofol and fentanyl. Hemodynamics and other variables were recorded preinduction, and before and 1 minute after intubation. RESULTS: The two groups were compared with regard to demographic and perioperative data. The two groups were similar demographically, and no significant differences was found in any hemodynamic parameter at any time between the two groups. CONCLUSIONS: Both fentanyl regimens provided stable hemodynamics and adequate anesthesia in patients during endotracheal intubation. It is reasonable to say that the lower dose of fentanyl (5 ng/ml) may be the better choice, because it provides the same level of anesthesia during endotracheal intubation during coronary artery bypass graft surgery.
Airway Extubation ; Anesthesia ; Coronary Artery Bypass* ; Coronary Vessels* ; Fentanyl* ; Hemodynamics ; Humans ; Intubation ; Intubation, Intratracheal* ; Propofol ; Thoracic Surgery ; Transplants

OBJECTIVE: To investigate the accuracy of model-based iterative reconstruction (MIR) for volume measurement of part-solid nodules (PSNs) and solid nodules (SNs) in comparison with filtered back projection (FBP) or hybrid iterative reconstruction (HIR) at various radiation dose settings. MATERIALS AND METHODS: CT scanning was performed for eight different diameters of PSNs and SNs placed in the phantom at five radiation dose levels (120 kVp/100 mAs, 120 kVp/50 mAs, 120 kVp/20 mAs, 120 kVp/10 mAs, and 80 kVp/10 mAs). Each CT scan was reconstructed using FBP, HIR, or MIR with three different image definitions (body routine level 1 [IMR-R1], body soft tissue level 1 [IMR-ST1], and sharp plus level 1 [IMR-SP1]; Philips Healthcare). The SN and PSN volumes including each solid/ground-glass opacity portion were measured semi-automatically, after which absolute percentage measurement errors (APEs) of the measured volumes were calculated. Image noise was calculated to assess the image quality. RESULTS: Across all nodules and dose settings, the APEs were significantly lower in MIR than in FBP and HIR (all p < 0.01). The APEs of the smallest inner solid portion of the PSNs (3 mm) and SNs (3 mm) were the lowest when MIR (IMR-R1 and IMR-ST1) was used for reconstruction for all radiation dose settings. (IMR-R1 and IMR-ST1 at 120 kVp/100 mAs, 1.06 ± 1.36 and 8.75 ± 3.96, p < 0.001; at 120 kVp/50 mAs, 1.95 ± 1.56 and 5.61 ± 0.85, p = 0.002; at 120 kVp/20 mAs, 2.88 ± 3.68 and 5.75 ± 1.95, p = 0.001; at 120 kVp/10 mAs, 5.57 ± 6.26 and 6.32 ± 2.91, p = 0.091; at 80 kVp/10 mAs, 5.84 ± 1.96 and 6.90 ± 3.31, p = 0.632). Image noise was significantly lower in MIR than in FBP and HIR for all radiation dose settings (120 kVp/100 mAs, 3.22 ± 0.66; 120 kVp/50 mAs, 4.19 ± 1.37; 120 kVp/20 mAs, 5.49 ± 1.16; 120 kVp/10 mAs, 6.88 ± 1.91; 80 kVp/10 mAs, 12.49 ± 6.14; all p < 0.001). CONCLUSION: MIR was the most accurate algorithm for volume measurements of both PSNs and SNs in comparison with FBP and HIR at low-dose as well as standard-dose settings. Specifically, MIR was effective in the volume measurement of the smallest PSNs and SNs.
Hominidae ; Humans ; Lung Neoplasms ; Multidetector Computed Tomography ; Noise ; Phantoms, Imaging ; Radiation Dosage ; Thorax ; Tomography, X-Ray Computed

OBJECTIVE: To compare correlations between pulmonary function test (PFT) results and different reconstruction algorithms and to suggest the optimal reconstruction protocol for computed tomography (CT) quantification of low lung attenuation areas and airways in healthy individuals. MATERIALS AND METHODS: A total of 259 subjects with normal PFT and chest CT results were included. CT scans were reconstructed using filtered back projection, hybrid-iterative reconstruction, and model-based IR (MIR). For quantitative analysis, the emphysema index (EI) and wall area percentage (WA%) were determined. Subgroup analysis according to smoking history was also performed. RESULTS: The EIs of all the reconstruction algorithms correlated significantly with the forced expiratory volume in one second (FEV1)/forced vital capacity (FVC) (all p < 0.001). The EI of MIR showed the strongest correlation with FEV1/FVC (r = −0.437). WA% showed a significant correlation with FEV1 in all the reconstruction algorithms (all p < 0.05) correlated significantly with FEV1/FVC for MIR only (p < 0.001). The WA% of MIR showed the strongest correlations with FEV1 (r = −0.205) and FEV1/FVC (r = −0.250). In subgroup analysis, the EI of MIR had the strongest correlation with PFT in both ever-smoker and never-smoker subgroups, although there was no significant difference in the EI between the reconstruction algorithms. WA% of MIR showed a significantly thinner airway thickness than the other algorithms (49.7 ± 7.6 in ever-smokers and 49.5 ± 7.5 in never-smokers, all p < 0.001), and also showed the strongest correlation with PFT in both ever-smoker and never-smoker subgroups. CONCLUSION: CT quantification of low lung attenuation areas and airways by means of MIR showed the strongest correlation with PFT results among the algorithms used, in normal subjects.
Emphysema ; Forced Expiratory Volume ; Lung* ; Pulmonary Emphysema ; Respiratory Function Tests* ; Smoke ; Smoking ; Tomography, X-Ray Computed ; Vital Capacity

Computed tomography (CT) is an important imaging modality in evaluating thoracic malignancies. The clinical utility of dual-energy spectral computed tomography (DESCT) has recently been realized. DESCT allows for virtual monoenergetic or monochromatic imaging, virtual non-contrast or unenhanced imaging, iodine concentration measurement, and effective atomic number (Zeff map). The application of information gained using this technique in the field of thoracic oncology is important, and therefore many studies have been conducted to explore the use of DESCT in the evaluation and management of thoracic malignancies. Here we summarize and review recent DESCT studies on clinical applications related to thoracic oncology.