2.Temporal Radiographic Trajectory and Clinical Outcomes in COVID-19Pneumonia: A Longitudinal Study
Dong-Won AHN ; Yeonju SEO ; Taewan GOO ; Ji Bong JEONG ; Taesung PARK ; Soon Ho YOON
Journal of Korean Medical Science 2025;40(9):e25-
Background:
Currently, little is known about the relationship between the temporal radiographic latent trajectories, which are based on the extent of coronavirus disease 2019 (COVID-19) pneumonia and clinical outcomes. This study aimed to elucidate the differences in the temporal trends of critical laboratory biomarkers, utilization of critical care support, and clinical outcomes according to temporal radiographic latent trajectories.
Methods:
We enrolled 2,385 patients who were hospitalized with COVID-19 and underwent serial chest radiographs from December 2019 to March 2022. The extent of radiographic pneumonia was quantified as a percentage using a previously developed deep-learning algorithm. A latent class growth model was used to identify the trajectories of the longitudinal changes of COVID-19 pneumonia extents during hospitalization. We investigated the differences in the temporal trends of critical laboratory biomarkers among the temporal radiographic trajectory groups. Cox regression analyses were conducted to investigate differences in the utilization of critical care supports and clinical outcomes among the temporal radiographic trajectory groups.
Results:
The mean age of the enrolled patients was 58.0 ± 16.9 years old, with 1,149 (48.2%) being male. Radiographic pneumonia trajectories were classified into three groups: The steady group (n = 1,925, 80.7%) exhibited stable minimal pneumonia, the downhill group (n = 135, 5.7%) exhibited initial worsening followed by improving pneumonia, and the uphill group (n = 325, 13.6%) exhibited progressive deterioration of pneumonia. There were distinct differences in the patterns of temporal blood urea nitrogen (BUN) and C-reactive protein (CRP) levels between the uphill group and the other two groups. Cox regression analyses revealed that the hazard ratios (HRs) for the need for critical care support and the risk of intensive care unit admission were significantly higher in both the downhill and uphill groups compared to the steady group. However, regarding in-hospital mortality, only the uphill group demonstrated a significantly higher risk than the steady group (HR, 8.2; 95% confidence interval, 3.08–21.98).
Conclusion
Stratified pneumonia trajectories, identified through serial chest radiographs, are linked to different patterns of temporal changes in BUN and CRP levels. These changes can predict the need for critical care support and clinical outcomes in COVID-19 pneumonia.Appropriate therapeutic strategies should be tailored based on these disease trajectories.
3.Early Administration of Nelonemdaz May Improve the Stroke Outcomes in Patients With Acute Stroke
Jin Soo LEE ; Ji Sung LEE ; Seong Hwan AHN ; Hyun Goo KANG ; Tae-Jin SONG ; Dong-Ick SHIN ; Hee-Joon BAE ; Chang Hun KIM ; Sung Hyuk HEO ; Jae-Kwan CHA ; Yeong Bae LEE ; Eung Gyu KIM ; Man Seok PARK ; Hee-Kwon PARK ; Jinkwon KIM ; Sungwook YU ; Heejung MO ; Sung Il SOHN ; Jee Hyun KWON ; Jae Guk KIM ; Young Seo KIM ; Jay Chol CHOI ; Yang-Ha HWANG ; Keun Hwa JUNG ; Soo-Kyoung KIM ; Woo Keun SEO ; Jung Hwa SEO ; Joonsang YOO ; Jun Young CHANG ; Mooseok PARK ; Kyu Sun YUM ; Chun San AN ; Byoung Joo GWAG ; Dennis W. CHOI ; Ji Man HONG ; Sun U. KWON ;
Journal of Stroke 2025;27(2):279-283
5.Temporal Radiographic Trajectory and Clinical Outcomes in COVID-19Pneumonia: A Longitudinal Study
Dong-Won AHN ; Yeonju SEO ; Taewan GOO ; Ji Bong JEONG ; Taesung PARK ; Soon Ho YOON
Journal of Korean Medical Science 2025;40(9):e25-
Background:
Currently, little is known about the relationship between the temporal radiographic latent trajectories, which are based on the extent of coronavirus disease 2019 (COVID-19) pneumonia and clinical outcomes. This study aimed to elucidate the differences in the temporal trends of critical laboratory biomarkers, utilization of critical care support, and clinical outcomes according to temporal radiographic latent trajectories.
Methods:
We enrolled 2,385 patients who were hospitalized with COVID-19 and underwent serial chest radiographs from December 2019 to March 2022. The extent of radiographic pneumonia was quantified as a percentage using a previously developed deep-learning algorithm. A latent class growth model was used to identify the trajectories of the longitudinal changes of COVID-19 pneumonia extents during hospitalization. We investigated the differences in the temporal trends of critical laboratory biomarkers among the temporal radiographic trajectory groups. Cox regression analyses were conducted to investigate differences in the utilization of critical care supports and clinical outcomes among the temporal radiographic trajectory groups.
Results:
The mean age of the enrolled patients was 58.0 ± 16.9 years old, with 1,149 (48.2%) being male. Radiographic pneumonia trajectories were classified into three groups: The steady group (n = 1,925, 80.7%) exhibited stable minimal pneumonia, the downhill group (n = 135, 5.7%) exhibited initial worsening followed by improving pneumonia, and the uphill group (n = 325, 13.6%) exhibited progressive deterioration of pneumonia. There were distinct differences in the patterns of temporal blood urea nitrogen (BUN) and C-reactive protein (CRP) levels between the uphill group and the other two groups. Cox regression analyses revealed that the hazard ratios (HRs) for the need for critical care support and the risk of intensive care unit admission were significantly higher in both the downhill and uphill groups compared to the steady group. However, regarding in-hospital mortality, only the uphill group demonstrated a significantly higher risk than the steady group (HR, 8.2; 95% confidence interval, 3.08–21.98).
Conclusion
Stratified pneumonia trajectories, identified through serial chest radiographs, are linked to different patterns of temporal changes in BUN and CRP levels. These changes can predict the need for critical care support and clinical outcomes in COVID-19 pneumonia.Appropriate therapeutic strategies should be tailored based on these disease trajectories.
6.Early Administration of Nelonemdaz May Improve the Stroke Outcomes in Patients With Acute Stroke
Jin Soo LEE ; Ji Sung LEE ; Seong Hwan AHN ; Hyun Goo KANG ; Tae-Jin SONG ; Dong-Ick SHIN ; Hee-Joon BAE ; Chang Hun KIM ; Sung Hyuk HEO ; Jae-Kwan CHA ; Yeong Bae LEE ; Eung Gyu KIM ; Man Seok PARK ; Hee-Kwon PARK ; Jinkwon KIM ; Sungwook YU ; Heejung MO ; Sung Il SOHN ; Jee Hyun KWON ; Jae Guk KIM ; Young Seo KIM ; Jay Chol CHOI ; Yang-Ha HWANG ; Keun Hwa JUNG ; Soo-Kyoung KIM ; Woo Keun SEO ; Jung Hwa SEO ; Joonsang YOO ; Jun Young CHANG ; Mooseok PARK ; Kyu Sun YUM ; Chun San AN ; Byoung Joo GWAG ; Dennis W. CHOI ; Ji Man HONG ; Sun U. KWON ;
Journal of Stroke 2025;27(2):279-283
7.Effects of Deep Learning-Based Reconstruction on the Quality of Accelerated Contrast-Enhanced Neck MRI
Minkook SEO ; Kook-Jin AHN ; Hyun-Soo LEE ; Marcel Dominik NICKEL ; Jinhee JANG ; Yeon Jong HUH ; Ilah SHIN ; Ji Young LEE ; Bum-soo KIM
Korean Journal of Radiology 2025;26(5):446-459
Objective:
To compare the quality of deep learning-reconstructed turbo spin-echo (DL-TSE) and conventionally interpolated turbo spin-echo (Conv-TSE) techniques in contrast-enhanced MRI of the neck.
Materials and Methods:
Contrast-enhanced T1-weighted DL-TSE and Conv-TSE images were acquired using 3T scanners from 106 patients. DL-TSE employed a closed-source, ‘work-in-progress’ (WIP No. 1062, iTSE, version 10; Siemens Healthineers) algorithm for interpolation and denoising to achieve the same in-plane resolution (axial: 0.26 x 0.26 mm 2 ; coronal: 0.29 x 0.29 mm 2 ) while reducing scan times by 15.9% and 52.6% for axial and coronal scans, respectively. The full width at half maximum (FWHM) and percent signal ghosting were measured using stationary and flow phantom scans, respectively. In patient images, non-uniformity (NU), contrast-to-noise ratio (CNR), and regional mucosal FWHM were evaluated. Two neuroradiologists visually rated the patient images for overall quality, sharpness, regional mucosal conspicuity, artifacts, and lesions using a 5-point Likert scale.
Results:
FWHM in the stationary phantom scan was consistently sharper in DL-TSE. The percent signal ghosting outside the flow phantom was lower in DL-TSE (0.06% vs. 0.14%) but higher within the phantom (8.92% vs. 1.75%) compared to ConvTSE. In patient scans, DL-TSE showed non-inferior NU and higher CNR. Regional mucosal FWHM was significantly better in DL-TSE, particularly in the oropharynx (coronal: 1.08 ± 0.31 vs. 1.52 ± 0.46 mm) and hypopharynx (coronal: 1.26 ± 0.35 vs. 1.91 ± 0.56 mm) (both P < 0.001). DL-TSE demonstrated higher overall image quality (axial: 4.61 ± 0.49 vs. 3.32 ± 0.54) and sharpness (axial: 4.40 ± 0.56 vs. 3.11 ± 0.53) (both P < 0.001). In addition, mucosal conspicuity was improved, especially in the oropharynx (axial: 4.41 ± 0.67 vs. 3.40 ± 0.69) and hypopharynx (axial: 4.45 ± 0.58 vs. 3.58 ± 0.63) (both P < 0.001).Extracorporeal ghost artifacts were reduced in DL-TSE (axial: 4.32 ± 0.60 vs. 3.90 ± 0.71, P < 0.001) but artifacts overlapping anatomical structures were slightly more pronounced (axial: 3.78 ± 0.74 vs. 3.95 ± 0.72, P < 0.001). Lesions were detected with higher confidence in DL-TSE.
Conclusion
DL-based reconstruction applied to accelerated neck MRI improves overall image quality, sharpness, mucosal conspicuity in motion-prone regions, and lesion detection confidence. Despite more pronounced ghost artifacts overlapping anatomical structures, DL-TSE enables substantial scan time reduction while enhancing diagnostic performance.
8.Endoscopic features of cytomegalovirus disease of the upper gastrointestinal tract between transplant and non-transplant patients
Yuri KIM ; Do Hoon KIM ; Myeongsook SEO ; Hee Kyong NA ; Kee Wook JUNG ; Ji Yong AHN ; Jeong Hoon LEE ; Kee Don CHOI ; Ho June SONG ; Gin Hyug LEE ; Hwoon-Yong JUNG
The Korean Journal of Internal Medicine 2025;40(3):394-403
Background/Aims:
Cytomegalovirus (CMV) disease in the upper gastrointestinal (UGI) tract frequently occurs in immunocompromised patients. However, data regarding UGI CMV disease in non-transplant patients compared with those in transplant recipients are limited. Therefore, we compared the clinical characteristics, endoscopic findings, and outcomes of UGI CMV disease in non-transplant patients with those in transplant recipients.
Methods:
We reviewed the medical records of patients diagnosed with UGI CMV disease between May 1999 and January 2022. UGI CMV disease was defined as symptoms or signs of gastrointestinal disease with typical findings of CMV inclusion body and positive immunochemistry stain or CMV polymerase chain reaction from the endoscopic biopsy specimen.
Results:
Among the 219 eligible patients, 132 (60.3%) were transplant patients. Age, male sex, and Charlson Comorbidity Index were significantly higher in the non-transplant group than in the transplant group. The most common symptoms were pain and odynophagia (43.8%). Transplant recipients more frequently experienced UGI CMV disease in the stomach than non-transplant patients, typically presenting as erosions or mucosal hyperemia. However, non-transplant patients more commonly experienced UGI CMV disease in the esophagus than transplant recipients, typically presenting as ulcers. The transplant group had a significantly higher clinical response than the non-transplant group.
Conclusions
UGI CMV disease in transplant patients can be present in the stomach in various forms, including ulcers or erosions. In transplant patients suspected of UGI CMV disease, conducting an esophagogastroduodenoscopy with tissue biopsy in any area where even the slightest mucosal abnormality is observed is essential to facilitate a prompt diagnosis.
9.Early Administration of Nelonemdaz May Improve the Stroke Outcomes in Patients With Acute Stroke
Jin Soo LEE ; Ji Sung LEE ; Seong Hwan AHN ; Hyun Goo KANG ; Tae-Jin SONG ; Dong-Ick SHIN ; Hee-Joon BAE ; Chang Hun KIM ; Sung Hyuk HEO ; Jae-Kwan CHA ; Yeong Bae LEE ; Eung Gyu KIM ; Man Seok PARK ; Hee-Kwon PARK ; Jinkwon KIM ; Sungwook YU ; Heejung MO ; Sung Il SOHN ; Jee Hyun KWON ; Jae Guk KIM ; Young Seo KIM ; Jay Chol CHOI ; Yang-Ha HWANG ; Keun Hwa JUNG ; Soo-Kyoung KIM ; Woo Keun SEO ; Jung Hwa SEO ; Joonsang YOO ; Jun Young CHANG ; Mooseok PARK ; Kyu Sun YUM ; Chun San AN ; Byoung Joo GWAG ; Dennis W. CHOI ; Ji Man HONG ; Sun U. KWON ;
Journal of Stroke 2025;27(2):279-283
10.Effects of Deep Learning-Based Reconstruction on the Quality of Accelerated Contrast-Enhanced Neck MRI
Minkook SEO ; Kook-Jin AHN ; Hyun-Soo LEE ; Marcel Dominik NICKEL ; Jinhee JANG ; Yeon Jong HUH ; Ilah SHIN ; Ji Young LEE ; Bum-soo KIM
Korean Journal of Radiology 2025;26(5):446-459
Objective:
To compare the quality of deep learning-reconstructed turbo spin-echo (DL-TSE) and conventionally interpolated turbo spin-echo (Conv-TSE) techniques in contrast-enhanced MRI of the neck.
Materials and Methods:
Contrast-enhanced T1-weighted DL-TSE and Conv-TSE images were acquired using 3T scanners from 106 patients. DL-TSE employed a closed-source, ‘work-in-progress’ (WIP No. 1062, iTSE, version 10; Siemens Healthineers) algorithm for interpolation and denoising to achieve the same in-plane resolution (axial: 0.26 x 0.26 mm 2 ; coronal: 0.29 x 0.29 mm 2 ) while reducing scan times by 15.9% and 52.6% for axial and coronal scans, respectively. The full width at half maximum (FWHM) and percent signal ghosting were measured using stationary and flow phantom scans, respectively. In patient images, non-uniformity (NU), contrast-to-noise ratio (CNR), and regional mucosal FWHM were evaluated. Two neuroradiologists visually rated the patient images for overall quality, sharpness, regional mucosal conspicuity, artifacts, and lesions using a 5-point Likert scale.
Results:
FWHM in the stationary phantom scan was consistently sharper in DL-TSE. The percent signal ghosting outside the flow phantom was lower in DL-TSE (0.06% vs. 0.14%) but higher within the phantom (8.92% vs. 1.75%) compared to ConvTSE. In patient scans, DL-TSE showed non-inferior NU and higher CNR. Regional mucosal FWHM was significantly better in DL-TSE, particularly in the oropharynx (coronal: 1.08 ± 0.31 vs. 1.52 ± 0.46 mm) and hypopharynx (coronal: 1.26 ± 0.35 vs. 1.91 ± 0.56 mm) (both P < 0.001). DL-TSE demonstrated higher overall image quality (axial: 4.61 ± 0.49 vs. 3.32 ± 0.54) and sharpness (axial: 4.40 ± 0.56 vs. 3.11 ± 0.53) (both P < 0.001). In addition, mucosal conspicuity was improved, especially in the oropharynx (axial: 4.41 ± 0.67 vs. 3.40 ± 0.69) and hypopharynx (axial: 4.45 ± 0.58 vs. 3.58 ± 0.63) (both P < 0.001).Extracorporeal ghost artifacts were reduced in DL-TSE (axial: 4.32 ± 0.60 vs. 3.90 ± 0.71, P < 0.001) but artifacts overlapping anatomical structures were slightly more pronounced (axial: 3.78 ± 0.74 vs. 3.95 ± 0.72, P < 0.001). Lesions were detected with higher confidence in DL-TSE.
Conclusion
DL-based reconstruction applied to accelerated neck MRI improves overall image quality, sharpness, mucosal conspicuity in motion-prone regions, and lesion detection confidence. Despite more pronounced ghost artifacts overlapping anatomical structures, DL-TSE enables substantial scan time reduction while enhancing diagnostic performance.

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