Objective: To determine the preventive effect of changing gadolinium-based contrast agents (GBCAs) to reduce the recurrence of GBCA-associated acute adverse drug reactions (ADRs). Materials and Methods: This retrospective, observational, single-center study—conducted between January 2016 and December 2021—included 238743 consecutive GBCA-enhanced MRI examinations. We focused on a subgroup of patients who experienced acute GBCA-associated ADRs during any of these examinations and subsequently underwent follow-up GBCAenhanced MRI examinations up until July 2023. The follow-up examinations involved either the same (non-change group) or different (change group) GBCAs compared to the ones that initially caused the acute ADR. Baseline participant characteristics, generic profile of the GBCAs, administration of premedication, history of prior ADR to iodinated contrast media, and symptoms of GBCA-associated acute ADRs were retrospectively analyzed. Multivariable logistic regression with generalized estimating equations and propensity score matching were used. Results: A total of 1042 instances of acute ADRs (0.44%; 95% confidence interval [CI]: 0.41%–0.46%) were reported. Threehundred and seventy-three patients underwent GBCA-enhanced MRI examinations after experiencing GBCA-associated acute ADRs within the study period; 31.9% (119/373) reexperienced acute ADRs at any of the follow-up examinations. The ADR recurrence was significantly lower in the GBCA change group than in the non-change group according to multivariable logistic regression (adjusted odds ratio [OR]: 0.35; 95% CI: 0.13–0.90; P = 0.03) and analysis with propensity score matching (14.3% [6/42] vs. 36.9% [31/84], respectively; OR: 0.32, 95% CI: 0.11–0.94; P = 0.04). A history of an ADR to iodinated contrast media (OR: 1.14, 95% CI: 0.68–1.90; P = 0.62) and premedication (adjusted OR: 2.09, 95% CI: 0.93–4.68; P = 0.07) were not significantly associated with GBCA-associated acute ADR recurrence. A separate analysis for recurrent allergic-like hypersensitivity reactions demonstrated similar results (adjusted OR: 0.20, 95% CI: 0.06–0.65; P < 0.01). Conclusion Changing GBCAs may reduce the risk of GBCA-associated acute ADR recurrence.

Objective: To develop a deep-learning-based bone age prediction model optimized for Korean children and adolescents and evaluate its feasibility by comparing it with a Greulich-Pyle-based deep-learning model. Materials and Methods: A convolutional neural network was trained to predict age according to the bone development shown on a hand radiograph (bone age) using 21036 hand radiographs of Korean children and adolescents without known bone development-affecting diseases/conditions obtained between 1998 and 2019 (median age [interquartile range {IQR}], 9 [7–12] years; male:female, 11794:9242) and their chronological ages as labels (Korean model). We constructed 2 separate external datasets consisting of Korean children and adolescents with healthy bone development (Institution 1: n = 343;median age [IQR], 10 [4–15] years; male: female, 183:160; Institution 2: n = 321; median age [IQR], 9 [5–14] years; male:female, 164:157) to test the model performance. The mean absolute error (MAE), root mean square error (RMSE), and proportions of bone age predictions within 6, 12, 18, and 24 months of the reference age (chronological age) were compared between the Korean model and a commercial model (VUNO Med-BoneAge version 1.1; VUNO) trained with Greulich-Pyle-based age as the label (GP-based model). Results: Compared with the GP-based model, the Korean model showed a lower RMSE (11.2 vs. 13.8 months; P = 0.004) and MAE (8.2 vs. 10.5 months; P = 0.002), a higher proportion of bone age predictions within 18 months of chronological age (88.3% vs. 82.2%; P = 0.031) for Institution 1, and a lower MAE (9.5 vs. 11.0 months; P = 0.022) and higher proportion of bone age predictions within 6 months (44.5% vs. 36.4%; P = 0.044) for Institution 2. Conclusion The Korean model trained using the chronological ages of Korean children and adolescents without known bone development-affecting diseases/conditions as labels performed better in bone age assessment than the GP-based model in the Korean pediatric population. Further validation is required to confirm its accuracy.

Objective: Central nervous system involvement in coronavirus disease 2019 (COVID-19) has been increasingly reported. We performed a systematic review and meta-analysis to evaluate the incidence of radiologically demonstrated neurologic complications and detailed neuroimaging findings associated with COVID-19. Materials and Methods: A systematic literature search of MEDLINE/PubMed and EMBASE databases was performed up to September 17, 2020, and studies evaluating neuroimaging findings of COVID-19 using brain CT or MRI were included. Several cohort-based outcomes, including the proportion of patients with abnormal neuroimaging findings related to COVID-19 were evaluated. The proportion of patients showing specific neuroimaging findings was also assessed. Subgroup analyses were also conducted focusing on critically ill COVID-19 patients and results from studies that used MRI as the only imaging modality. Results: A total of 1394 COVID-19 patients who underwent neuroimaging from 17 studies were included; among them, 3.4% of the patients demonstrated COVID-19-related neuroimaging findings. Olfactory bulb abnormalities were the most commonly observed (23.1%). The predominant cerebral neuroimaging finding was white matter abnormality (17.6%), followed by acute/subacute ischemic infarction (16.0%), and encephalopathy (13.0%). Significantly more critically ill patients had COVID-19-related neuroimaging findings than other patients (9.1% vs. 1.6%; p = 0.029). The type of imaging modality used did not significantly affect the proportion of COVID-19-related neuroimaging findings. Conclusion Abnormal neuroimaging findings were occasionally observed in COVID-19 patients. Olfactory bulb abnormalities were the most commonly observed finding. Critically ill patients showed abnormal neuroimaging findings more frequently than the other patient groups. White matter abnormalities, ischemic infarctions, and encephalopathies were the common cerebral neuroimaging findings.

Duodenal varices are a serious complication of portal hypertension. Bleeding from duodenal varices is rare, but when bleeding does occur, it is massive and can be fatal. Unfortunately, the optimal therapeutic modality for duodenal variceal bleeding is unclear. This paper presents a patient with duodenal variceal bleeding that was managed successfully using percutaneous trans-splenic variceal obliteration (PTVO). A 56-year-old man with a history of alcoholic cirrhosis presented with a 6-day history of melena. Emergency esophagogastroduodenoscopy revealed a large, bluish mass with a nipple sign in the second portion of the duodenum. Coil embolization of the duodenal varix was performed via a trans-splenic approach (i.e., PTVO). The patient no longer complained of melena after treatment. The duodenal varix was no longer visible at the follow-up esophagogastroduodenoscopy performed three months after PTVO. The use of PTVO might be a viable option for the treatment of duodenal variceal bleeding.

Duodenal varices are a serious complication of portal hypertension. Bleeding from duodenal varices is rare, but when bleeding does occur, it is massive and can be fatal. Unfortunately, the optimal therapeutic modality for duodenal variceal bleeding is unclear. This paper presents a patient with duodenal variceal bleeding that was managed successfully using percutaneous trans-splenic variceal obliteration (PTVO). A 56-year-old man with a history of alcoholic cirrhosis presented with a 6-day history of melena. Emergency esophagogastroduodenoscopy revealed a large, bluish mass with a nipple sign in the second portion of the duodenum. Coil embolization of the duodenal varix was performed via a trans-splenic approach (i.e., PTVO). The patient no longer complained of melena after treatment. The duodenal varix was no longer visible at the follow-up esophagogastroduodenoscopy performed three months after PTVO. The use of PTVO might be a viable option for the treatment of duodenal variceal bleeding.