Objective:The aim of this study was to assess the effectiveness of a deep learning-based image contrast-boosting algorithm by enhancing the image quality of low-dose computed tomography pulmonary angiography at reduced iodine load. Methods:This study included 179 patients who underwent low-dose computed tomography pulmonary angiography with a reduced iodine load using 64 mL of a 1:1 mixture of contrast medium from January 1 to June 30, 2023. For single-energy computed tomography, the noise index was set at 15.4 to maintain a CTDIvol of <2 mGy at 80 kVp, and for dual-energy computed tomography, fast kV-switching between 80 and 140 kVp was employed with a fixed tube current of 145 mA. Images were reconstructed by 50% adaptive statistical iterative reconstruction (AR50) and a commercially available deep learning image reconstruction (TrueFidelity) package at a high strength level (TFH). In addition, AR50 images were further processed using a deep learning-based contrast-boosting algorithm (AR50-CB). Quantitative and qualitative image qualities and numbers of involved vessels with thrombus at each pulmonary artery level were compared in the 3 image types using the Friedman test and Wilcoxon signed rank test. Results:Five hundred thirty-seven reconstructed image datasets of 179 patients were analyzed. Quantitative image analysis showed AR50-CB (30.8 +/- 10.0 and 28.1 +/- 9.6, respectively) had significantly higher signal-to-noise ratio and contrast-to-noise ratio values than AR50 (20.2 +/- 6.2 and 17.8 +/- 6.2, respectively) (P < 0.001) or TFH (28.3 +/- 8.3 and 24.9 +/- 8.1, respectively) (P < 0.001). Qualitative image analysis showed that contrast enhancement and noise scores of AR50-CB were significantly greater than those of AR50 (P < 0.001) and that AR50-CB enhancement scores were significantly higher than TFH enhancement scores (P < 0.001). The number of subsegmental pulmonary arteries affected by thrombus detected was significantly greater for AR50-CB (30 for AR50, 30 for TFH, and 55 for AR50-CB, P < 0.001). Conclusions:The use of a deep learning-based contrast-boosting algorithm improved image quality in terms of signal-to-noise ratio and contrast-to-noise ratio values and the detection of thrombi in subsegmental pulmonary arteries.

Chest MRI is a valuable tool for assessing chest structures, particularly when CT produces inconclusive results. MRI provides exceptional soft-tissue resolution and enables the determination of lesion location, size, and invasion into neighboring structures. Its applications span various clinical scenarios, including the differentiation of non-tumorous and tumorous conditions in the mediastinum or pleura, planning of surgical interventions and treatments for such tumors, evaluation of post-treatment recurrence, staging of lung cancer, and diagnosis of progressive massive fibrosis. Despite the technical hurdles posed by cardiac and respiratory motion, advancements in sequence and scan techniques have enabled high-quality chest MRI examinations to be conducted across diverse clinical settings. This pictorial essay aims to offer comprehensive resources and strategies for radiologists to integrate chest MRI into clinical practice and to overcome its present challenges.

Immunoglobulin G4-related disease (IgG4-RD) is an immune-mediated condition characterized by mass-forming inflammation with a sclerosing pattern that can affect nearly any organ. However, involvement of the diaphragm in IgG4-RD is exceptionally rare. We present the case of a 62-year-old male patient with chest radiographic abnormalities. Further investigation with CT revealed an infiltrative mass in the right hemidiaphragm. This mass, composed of engorged feeding vessels, an atypical manifestation of IgG4-RD, was also associated with lymphadenopathy. Surgical excision confirmed the presence of IgG4-positive cell infiltration, solidifying the diagnosis of IgG4-RD. Notably, the patient remained asymptomatic and did not require any treatment postoperatively. This case highlights the uncommon presentation of IgG4-RD as an infiltrative diaphragmatic mass.

Background and Objectives: Although reducing the radiation dose level is important during diagnostic computed tomography (CT) applications, effective image quality enhancement strategies are crucial to compensate for the degradation that is caused by a dose reduction. We performed this prospective study to quantify emphysema on ultra-low-dose CT images that were reconstructed using deep learning-based image reconstruction (DLIR) algorithms, and compared and evaluated the accuracies of DLIR algorithms versus standard-dose CT. Materials and Methods: A total of 32 patients were prospectively enrolled, and all underwent standard-dose and ultra-low-dose (120 kVp; CTDIvol < 0.7 mGy) chest CT scans at the same time in a single examination. A total of six image datasets (filtered back projection (FBP) for standard-dose CT, and FBP, adaptive statistical iterative reconstruction (ASIR-V) 50%, DLIR-low, DLIR-medium, DLIR-high for ultra-low-dose CT) were reconstructed for each patient. Image noise values, emphysema indices, total lung volumes, and mean lung attenuations were measured in the six image datasets and compared (one-way repeated measures ANOVA). Results: The mean effective doses for standard-dose and ultra-low-dose CT scans were 3.43 ± 0.57 mSv and 0.39 ± 0.03 mSv, respectively (p < 0.001). The total lung volume and mean lung attenuation of five image datasets of ultra-low-dose CT scans, emphysema indices of ultra-low-dose CT scans reconstructed using ASIR-V 50 or DLIR-low, and the image noise of ultra-low-dose CT scans that were reconstructed using DLIR-low were not different from those of standard-dose CT scans. Conclusions: Ultra-low-dose CT images that were reconstructed using DLIR-low were found to be useful for emphysema quantification at a radiation dose of only 11% of that required for standard-dose CT.

BACKGROUND:Chest radiography value as a screening tool in those exposed to pulmonary tuberculosis (TB) is reduced by its lower sensitivity to detect small intrapulmonary lesions.PURPOSE:To evaluate the efficacy of digital tomosynthesis (DTS) screening of individuals that had contacted persons with active TB using low-dose computed tomography (CT) as the reference standard methods.MATERIAL AND METHODS:This retrospective, community-based screening study of 90 adults who had been in close contact with a TB case was undertaken at our institution. All individuals underwent clinical evaluation, digital radiography (DR), DTS, and low-dose chest CT. Observers assessed and classified DR and DTS images using CT as the reference-standard method. Based on clinical and imaging findings, TB status was classified as normal, latent, minimal, subclinical, and active. Diagnostic performances of DTS and DR for the interpretation of correct diagnosis were calculated.RESULTS:The estimated effective doses for DR, DTS, and low-dose CT were 0.01 mSv, 0.1 mSv, and 0.33 mSv, respectively. TB statuses of the 90 individuals were as follows: 62 latent (68.9%); two subclinical (2.2%); and one minimal (1.1%). The sensitivities, specificities, and accuracies of DTS and DR in the interpretation of correct diagnosis were 75.8%, 100%, 91.1% and 48.5%, 96.5%, 78.9%, respectively.CONCLUSION:DTS appears to be superior to DR for the detection of lung lesions in individuals with TB contacts. DTS can offer a reasonable option for TB contact investigation.

Background: Extracorporeal membrane oxygenation (ECMO) can be used in patients with refractory cardiogenic shock or respiratory failure. In South Korea, the need for transporting ECMO patients is increasing. Nonetheless, information on urgent transportation and its outcomes is scant. Methods: In this retrospective review of 5 years of experience in ECMO transportation at a single center, the clinical outcomes of transported patients were compared with those of in-hospital patients. The effects of transportation and the relationship between insertion- departure time and survival were also analyzed. Results: There were 323 cases of in-hospital ECMO (in-hospital group) and 29 cases transferred to Hallym University Sacred Heart Hospital without adverse events (mobile group). The median transportation time was 95 minutes (interquartile range [IQR], 36.5-119.5 minutes), whereas the median transportation distance was 115 km (IQR, 15-115 km).Transpor- tation itself was not an independent risk factor for 28-day mortality (odds ratio [OR], 0.818; IQR, 0.381-1.755; p=0.605), long-term mortality (OR, 1.099; IQR, 0.680-1.777; p=0.700), and failure of ECMO weaning (OR, 1.003; IQR, 0.467-2.152; p=0.995) or survival to discharge (OR, 0.732; IQR, 0.337-1.586; p=0.429). After adjustment for covariates, no significant difference in the ECMO insertion-departure time was found between the survival and mortality groups (p=0.435). Conclusion: The outcomes of urgent transportation, with active involvement of the ECMO center before ECMO insertion and adherence to the transport protocol, were comparable to those of in-hospital ECMO patients.

Background: Few studies have classified chest computed tomography (CT) findings of coronavirus disease 2019 (COVID-19) and analyzed their correlations with prognosis. The present study aimed to evaluate retrospectively the clinical and chest CT findings of COVID-19 and to analyze CT findings and determine their relationships with clinical severity. Methods: Chest CT and clinical features of 271 COVID-19 patients were assessed. The presence of CT findings and distribution of parenchymal abnormalities were evaluated, and CT patterns were classified as bronchopneumonia, organizing pneumonia (OP), or diffuse alveolar damage (DAD). Total extents were assessed using a visual scoring system and artificial intelligence software. Patients were allocated to two groups based on clinical outcomes, that is, to a severe group (requiring O-2 therapy or mechanical ventilation, n = 55) or a mild group (not requiring O-2 therapy or mechanical ventilation, n = 216). Clinical and CT features of these two groups were compared and univariate and multivariate logistic regression analyses were performed to identify independent prognostic factors. Results: Age, lymphocyte count, levels of C-reactive protein, and procalcitonin were significantly different in the two groups. Forty-five of the 271 patients had normal chest CT findings. The most common CT findings among the remaining 226 patients were ground-glass opacity (98%), followed by consolidation (53%). CT findings were classified as OP (93%), DAD (4%), or bronchopneumonia (3%) and all nine patients with DAD pattern were included in the severe group. Uivariate and multivariate analyses showed an elevated procalcitonin (odds ratio (OR), 2.521; 95% confidence interval (CI], 1.001-6.303, P= 0.048), and higher visual CT scores (OR, 1.137; 95% CI, 1.042-1.236; P= 0.003) or higher total extent by AI measurement (OR, 1.048; 95% CI, 1.020-1.076; P< 0.001) were significantly associated with a severe clinical course. Conclusion: CT findings of COVID-19 pneumonia can be classified into OP, DAD, or bronchopneumonia patterns and all patients with DAD pattern were included in severe group. Elevated inflammatory markers and higher CT scores were found to be significant predictors of poor prognosis in patients with COVID-19 pneumonia.

Background: Ultrasound techniques are generally not used as a primary tool in the evaluation of mediastinal tumors and cysts. This study aimed to identify factors associated with pulmonary hypertension (PH) measured by transthoracic echocardiography (TTE) in patients with a mediastinal tumor. Methods: This retrospective, observational study was performed from January 2015 to December 2020. Fifty-five patients (mean age, 62 ± 13 years; 31 [56%] women) who had a mediastinal tumor and underwent TTE were included. Patients were classified as with PH or without PH. We analyzed clinical factors and echocardiographic parameters. Results: PH was found in 21 (38%) patients. Twenty-two patients were asymptomatic, and none had symptoms associated with PH. Forty-seven (86%) patients underwent surgery, and 23 (42%) patients were diagnosed with malignant tumors. The presence of PH was not related with malignancy. Patients with PH were older than those without PH (67 ± 10 versus [vs.] 59 ± 14 years, p = 0.017). Small left ventricular (LV) systolic dimension (29.4 ± 3.6 vs. 31.6 ± 3.6 mm, p = 0.040) and dimension (4.2 ± 0.3 vs. 4.5 ± 0.3 mm, p = 0.004) and hyperdynamic LV ejection fraction (EF, 69 ± 6 vs. 65 ± 5%, p = 0.019) were associated with PH. Among them, older age, small LV dimension, and high EF were independently associated with PH. Conclusion: The presence of PH had no significant effect on patients’ clinical manifestation or malignancy.

"Calcified masses on the mitral valve in a patient on ­haemodialysis." Acta Cardiologica, 72(4), pp. 497–498

BACKGROUND:Infective endocarditis is associated with not only cardiac complications but also neurologic, renal, musculoskeletal, and systemic complications related to the infection, such as embolization, metastatic infection, and mycotic aneurysm.CASE PRESENTATION:We report three cases (the first patient is Chinese and the other two are Koreans) of complicated infective endocarditis; two of the cases were associated with a mycotic aneurysm, and one case was associated with a splenic abscess. One case of a patient with prosthetic valve endocarditis was complicated by intracerebral hemorrhage caused by mycotic aneurysm rupture. A second case of a patient with right-sided valve endocarditis associated with a central catheter was complicated by an abdominal aortic mycotic aneurysm. The third patient had a splenic infarction and abscess associated with infected cardiac thrombi.CONCLUSIONS:Complicated infective endocarditis is rare and is associated with cardiac, neurologic, renal, musculoskeletal, and systemic complications related to infection, such as embolization, metastatic infection, and mycotic aneurysm. Infective endocarditis caused by Staphylococcus aureus is more frequently associated with complications. Because the mortality rate increases when complications develop, aggressive antibiotic therapy and surgery, combined with specific treatments for the complications, are necessary.

We report a case of successfully treated acute fulminant myocarditis induced by ulcerative colitis with extracorporeal life support and infliximab. Myocarditis is a rare but crucial complication during an exacerbation of inflammatory bowel disease. In our case, we applied extracorporeal membrane oxygenation (ECMO) for cardiac rest under impression of acute myocarditis associated with ulcerative colitis, and added infliximab for uncontrolled inflammation by corticosteroid. As a result, our patient was completely recovered with successful weaning of ECMO.

In the emergency department (ED), extracorporeal membrane oxygenation (ECMO) can be used as a rescue treatment modality for patients with refractory circulatory and/or respiratory failure. Serious consideration must be given to the indication, and the PRESERVE and RESP scores for mortality have been investigated. However these scores were validated to predict survival in patients who received mainly veno-venous (VV) ECMO in the intensive care unit. The aim of the present study was to investigate the factors that predicted the outcomes for patients who received mixed mode (veno-arterial [VA] and VV) ECMO support in the ED.

There has been controversy surrounding the late outcomes of Off-Pump Coronary Artery Bypass (OPCAB).

OBJECTIVE p53 mutations and the Ki-67 protein are frequently observed in various types of human cancer; the abnormal expression of p53 and Ki-67 in the tumor is associated with poor survival of lung cancer patients. We aimed to assess the prognostic role of immunohistochemical (IHC) expression of p53 and Ki-67 in lung adenocarcinoma tissue. METHODS Tumor samples from 136 patients who had undergone surgical resection for lung adenocarcinoma were retrospectively evaluated for p53 and Ki-67 expression by immunohistochemistry. Associations of clinical and pathologic variables with p53 and Ki-67 were determined using the χ(2) test. After excluding two patients (follow-up loss), 134 cases were evaluated for associations between p53, Ki-67, clinical and pathologic variables, and survival by using the Cox proportional hazards regression model and Kaplan-Meier method. RESULTS In the 136 patients, p53 was positive in 71.0% (93/131), and Ki-67 showed high in 49.2% (61/124). Unlike p53, Ki-67 was associated with male sex, smoking, and poor tumor differentiation (P=0.004, P=0.001 and P=0.006). Of these, poor tumor differentiation strongly was correlated with high level of Ki-67 expression (P=0.008). Neither p53 nor Ki-67 was associated with increased risk of death (P=0.318, P=0.053); however, age ≥60 years and lymph node involvement were significant predictors of death (P=0.039 and P=0.042). The log-rank test revealed a significant association between Ki-67 and lower survival in all patients (χ(2)=5637; P=0.018); however, the risk was limited to stage III cases (χ(2)=5.939; P=0.015). Unlike p53, patients with high level of Ki-67 expression showed lower 3-year actuarial survival than those without (log-rank test, χ(2)=4.936; P=0.026). CONCLUSIONS IHC expression of Ki-67 in lung adenocarcinoma tissue shows stronger association with poor tumor differentiation, and negatively affects patients' survival in advanced-stage lung cancer; however, the role of p53 on patient outcome needs further study.

Background: The aim of this study was to determine the long-term outcomes of surgical angioplasty for left main coronary artery (SA-LMCA) stenosis.Methods: We retrospectively analyzed data from 24 consecutive patients (mean age, 55 years; male/female, 12/12) who underwent a surgical angioplasty for the left main coronary artery (LMCA) stenosis at our institution between 1995 and 2002. We used autologous pericardium in 7 patients and bovine pericardium in 17 patients as a patch. We evaluated the late mortality and major adverse cardiac events (MACE) rate.Results: There was no operative mortality. Control coronary angiography exhibited wide open and funnel-shaped LMCA in all patients. One patient was lost to follow-up. During the mean follow-up of 167 months, there were 3 sudden cardiac deaths, 4 non-cardiac related deaths, and 9 MACE with one death at reoperation. The Kaplan-Meier method identified freedom from cardiac death in 95.7, 87.0, and 82.4% of the patients, and freedom from MACE in 91.3, 69.6, and 57.7% of the patients at 5, 10, and 15 years, respectively.Conclusions: This study demonstrated that the long-term outcomes of SA-LMCA with a pericardial patch are acceptable compared to those of coronary artery bypass grafting, despite the controversy over the indications and the patch material used.

Objective: Successful arteriovenous fistula (AVF) maturation is often challenging in obese patients. Optimal initial intraoperative blood flow (IOBF) is essential for adequate AVF maturation. This study was conducted to elucidate the effect of obesity on IOBF and radiocephalic AVF maturation.Methods: Patients with a newly created radiocephalic AVF were included (N = 252). Obesity was defined as a baseline body mass index (BMI) >= 25 kg/m(2), and primary maturation failure was defined as failure to use the AVF successfully by 3 months after its creation. IOBF was measured immediately after construction of the AVF with a VeriQ system (MediStim, Oslo, Norway).Results: The mean BMI was 24.1 +/- 3.9 kg/m(2), and the prevalence of obesity was 31.3%. Particularly, 8.3% (21 patients) had a BMI >= 30 kg/m(2). Primary maturation failure occurred in 100 patients (39.7%), and an IOBF <190 mL/min was closely associated with the risk of maturation failure (relative risk, 3.05; 95% confidence interval, 1.52-6.11). Compared with nonobese patients, obese subjects had a significantly higher prevalence of diabetes and elevated high-sensitivity C-reactive protein levels, whereas diameters of vessels were similar. When the patients were further divided into three groups as BMI <25, 25 to 29.9, and >= 30 kg/m(2), patients in the higher BMI group showed significantly lower IOBF and higher maturation failure rate. According to multivariate analysis, the statistically significant variables that determined maturation failure were obesity, previous vascular disease, increased high-sensitivity C-reactive protein levels, and IOBF <190 mL/min.Conclusions: Obese patients had a significantly lower IOBF, and both obesity and low IOBF contributed to the primary maturation failure of AVF. Obesity-associated inflammation and atherosclerosis might play roles in this association.

BACKGROUND:Conservation of blood during cardiac surgery is important because of the shortage of donor blood, risks associated with transfusion, and the costs of allogeneic blood products. This retrospective study explored the feasibility of off-pump coronary artery bypass (OPCAB) without transfusion. METHODS:One hundred and two consecutive patients underwent OPCAB from January 2007 to June 2012 at Hallym University Sacred Heart Hospital. Excluding 10 chronic renal failures patients, 102 patients were enrolled. Their characteristics, clinical data, and laboratory data were analyzed. We investigated the success rate of OPCAB without transfusion according to pre-operative hemoglobin (Hb), and the cutoff point of the Hb level and the risk factors for transfusion. We implemented multidisciplinary blood-saving protocols. RESULTS:The overall operative mortality and the success rate of OPCAB without transfusion were 2.9% (3/102) and 73.5% (75/102). The success rates in patients with Hb<11, 11 70 years, diagnosis of acute myocardial infarction, preoperative Hb and creatinine levels, and operation time. The events precipitating the need for transfusion were low Hb level in 9 patients and hypotension or excessive bleeding in 18 patients. CONCLUSION:The preoperative Hb level of >11 facilitates OPCAB without transfusion. These results suggest that transfusion-free OPCAB can be performed by modifying the risk factors and correctable causes of transfusion and improving various blood salvage methods.

The aim of this study was to determine the early outcomes of using extracorporeal membrane oxygenation (ECMO) in near-drowning patients with cardiac or pulmonary failure.

Myocardial infarction (MI) secondary to coronary artery fistula and the subsequent occlusion of the distal right coronary artery (RCA) after blunt chest trauma is a rare entity.Here, we describe a case of coronary artery fistula and occlusion with an inferior MI that occurred following blunt chest trauma.At the initial visit to the emergency room after a car accident, this patient had been undiagnosed with acute myocardial infarction, readmitted five months after ischemic insult, and revealed to have experienced MI due to RCA-right atrial fistula and occlusion of the distal RCA.He underwent coronary surgery and recovered without complications.