1.Establishing Regional Aβ Cutoffs andExploring Subgroup Prevalence Across Cognitive Stages Using BeauBrain Amylo®
Seongbeom PARK ; Kyoungmin KIM ; Soyeon YOON ; Seongmi KIM ; Jehyun AHN ; Kyoung Yoon LIM ; Hyemin JANG ; Duk L. NA ; Hee Jin KIM ; Seung Hwan MOON ; Jun Pyo KIM ; Sang Won SEO ; Jaeho KIM ; Kichang KWAK
Dementia and Neurocognitive Disorders 2025;24(2):135-146
Background:
and Purpose: Amyloid-beta (Aβ) plaques are key in Alzheimer’s disease (AD), with Aβ positron emission tomography imaging enabling non-invasive quantification.To address regional Aβ deposition, we developed regional Centiloid scales (rdcCL) and commercialized them through the computed tomography (CT)-based BeauBrain Amylo platform, eliminating the need for three-dimensional T1 magnetic resonance imaging (MRI).
Objective:
We aimed to establish robust regional Aβ cutoffs using the commercialized BeauBrain Amylo platform and to explore the prevalence of subgroups defined by global, regional, and striatal Aβ cutoffs across cognitive stages.
Methods:
We included 2,428 individuals recruited from the Korea-Registries to Overcome Dementia and Accelerate Dementia Research project. We calculated regional Aβ cutoffs using Gaussian Mixture Modeling. Participants were classified into subgroups based on global, regional, and striatal Aβ positivity across cognitive stages (cognitively unimpaired [CU], mild cognitive impairment, and dementia of the Alzheimer’s type).
Results:
MRI-based and CT-based global Aβ cutoffs were highly comparable and consistent with previously reported Centiloid values. Regional cutoffs revealed both similarities and differences between MRI- and CT-based methods, reflecting modality-specific segmentation processes. Subgroups such as global(−)regional(+) were more frequent in non-dementia stages, while global(+)striatal(−) was primarily observed in CU individuals.
Conclusions
Our study established robust regional Aβ cutoffs using a CT-based rdcCL method and demonstrated its clinical utility in classifying amyloid subgroups across cognitive stages. These findings highlight the importance of regional Aβ quantification in understanding amyloid pathology and its implications for biomarker-guided diagnosis and treatment in AD.
2.Establishing Regional Aβ Cutoffs andExploring Subgroup Prevalence Across Cognitive Stages Using BeauBrain Amylo®
Seongbeom PARK ; Kyoungmin KIM ; Soyeon YOON ; Seongmi KIM ; Jehyun AHN ; Kyoung Yoon LIM ; Hyemin JANG ; Duk L. NA ; Hee Jin KIM ; Seung Hwan MOON ; Jun Pyo KIM ; Sang Won SEO ; Jaeho KIM ; Kichang KWAK
Dementia and Neurocognitive Disorders 2025;24(2):135-146
Background:
and Purpose: Amyloid-beta (Aβ) plaques are key in Alzheimer’s disease (AD), with Aβ positron emission tomography imaging enabling non-invasive quantification.To address regional Aβ deposition, we developed regional Centiloid scales (rdcCL) and commercialized them through the computed tomography (CT)-based BeauBrain Amylo platform, eliminating the need for three-dimensional T1 magnetic resonance imaging (MRI).
Objective:
We aimed to establish robust regional Aβ cutoffs using the commercialized BeauBrain Amylo platform and to explore the prevalence of subgroups defined by global, regional, and striatal Aβ cutoffs across cognitive stages.
Methods:
We included 2,428 individuals recruited from the Korea-Registries to Overcome Dementia and Accelerate Dementia Research project. We calculated regional Aβ cutoffs using Gaussian Mixture Modeling. Participants were classified into subgroups based on global, regional, and striatal Aβ positivity across cognitive stages (cognitively unimpaired [CU], mild cognitive impairment, and dementia of the Alzheimer’s type).
Results:
MRI-based and CT-based global Aβ cutoffs were highly comparable and consistent with previously reported Centiloid values. Regional cutoffs revealed both similarities and differences between MRI- and CT-based methods, reflecting modality-specific segmentation processes. Subgroups such as global(−)regional(+) were more frequent in non-dementia stages, while global(+)striatal(−) was primarily observed in CU individuals.
Conclusions
Our study established robust regional Aβ cutoffs using a CT-based rdcCL method and demonstrated its clinical utility in classifying amyloid subgroups across cognitive stages. These findings highlight the importance of regional Aβ quantification in understanding amyloid pathology and its implications for biomarker-guided diagnosis and treatment in AD.
3.Establishing Regional Aβ Cutoffs andExploring Subgroup Prevalence Across Cognitive Stages Using BeauBrain Amylo®
Seongbeom PARK ; Kyoungmin KIM ; Soyeon YOON ; Seongmi KIM ; Jehyun AHN ; Kyoung Yoon LIM ; Hyemin JANG ; Duk L. NA ; Hee Jin KIM ; Seung Hwan MOON ; Jun Pyo KIM ; Sang Won SEO ; Jaeho KIM ; Kichang KWAK
Dementia and Neurocognitive Disorders 2025;24(2):135-146
Background:
and Purpose: Amyloid-beta (Aβ) plaques are key in Alzheimer’s disease (AD), with Aβ positron emission tomography imaging enabling non-invasive quantification.To address regional Aβ deposition, we developed regional Centiloid scales (rdcCL) and commercialized them through the computed tomography (CT)-based BeauBrain Amylo platform, eliminating the need for three-dimensional T1 magnetic resonance imaging (MRI).
Objective:
We aimed to establish robust regional Aβ cutoffs using the commercialized BeauBrain Amylo platform and to explore the prevalence of subgroups defined by global, regional, and striatal Aβ cutoffs across cognitive stages.
Methods:
We included 2,428 individuals recruited from the Korea-Registries to Overcome Dementia and Accelerate Dementia Research project. We calculated regional Aβ cutoffs using Gaussian Mixture Modeling. Participants were classified into subgroups based on global, regional, and striatal Aβ positivity across cognitive stages (cognitively unimpaired [CU], mild cognitive impairment, and dementia of the Alzheimer’s type).
Results:
MRI-based and CT-based global Aβ cutoffs were highly comparable and consistent with previously reported Centiloid values. Regional cutoffs revealed both similarities and differences between MRI- and CT-based methods, reflecting modality-specific segmentation processes. Subgroups such as global(−)regional(+) were more frequent in non-dementia stages, while global(+)striatal(−) was primarily observed in CU individuals.
Conclusions
Our study established robust regional Aβ cutoffs using a CT-based rdcCL method and demonstrated its clinical utility in classifying amyloid subgroups across cognitive stages. These findings highlight the importance of regional Aβ quantification in understanding amyloid pathology and its implications for biomarker-guided diagnosis and treatment in AD.
4.Establishing Regional Aβ Cutoffs andExploring Subgroup Prevalence Across Cognitive Stages Using BeauBrain Amylo®
Seongbeom PARK ; Kyoungmin KIM ; Soyeon YOON ; Seongmi KIM ; Jehyun AHN ; Kyoung Yoon LIM ; Hyemin JANG ; Duk L. NA ; Hee Jin KIM ; Seung Hwan MOON ; Jun Pyo KIM ; Sang Won SEO ; Jaeho KIM ; Kichang KWAK
Dementia and Neurocognitive Disorders 2025;24(2):135-146
Background:
and Purpose: Amyloid-beta (Aβ) plaques are key in Alzheimer’s disease (AD), with Aβ positron emission tomography imaging enabling non-invasive quantification.To address regional Aβ deposition, we developed regional Centiloid scales (rdcCL) and commercialized them through the computed tomography (CT)-based BeauBrain Amylo platform, eliminating the need for three-dimensional T1 magnetic resonance imaging (MRI).
Objective:
We aimed to establish robust regional Aβ cutoffs using the commercialized BeauBrain Amylo platform and to explore the prevalence of subgroups defined by global, regional, and striatal Aβ cutoffs across cognitive stages.
Methods:
We included 2,428 individuals recruited from the Korea-Registries to Overcome Dementia and Accelerate Dementia Research project. We calculated regional Aβ cutoffs using Gaussian Mixture Modeling. Participants were classified into subgroups based on global, regional, and striatal Aβ positivity across cognitive stages (cognitively unimpaired [CU], mild cognitive impairment, and dementia of the Alzheimer’s type).
Results:
MRI-based and CT-based global Aβ cutoffs were highly comparable and consistent with previously reported Centiloid values. Regional cutoffs revealed both similarities and differences between MRI- and CT-based methods, reflecting modality-specific segmentation processes. Subgroups such as global(−)regional(+) were more frequent in non-dementia stages, while global(+)striatal(−) was primarily observed in CU individuals.
Conclusions
Our study established robust regional Aβ cutoffs using a CT-based rdcCL method and demonstrated its clinical utility in classifying amyloid subgroups across cognitive stages. These findings highlight the importance of regional Aβ quantification in understanding amyloid pathology and its implications for biomarker-guided diagnosis and treatment in AD.
5.Effects of rapid antigen testing for pre-admission COVID-19 screening: a before and after study in the emergency department
Hyunwoo LEE ; Moon Hwan KWAK ; Hyun Kyung PARK ; Chang Hae PYO ; Keun Hong PARK ; Hahn Bom KIM ; Eun Mi HAM ; Jin Hyung PARK ; Dong Sun CHOI ; Jee Hyeon KIM ; Soo Bok CHOI
Journal of the Korean Society of Emergency Medicine 2025;36(6):221-231
Objective:
As the coronavirus disease 2019 (COVID-19) pandemic has been prolonged, the pre-hospital screening test performed in hospitals has changed from polymerase chain reaction (PCR) to rapid antigen test (RAT). RAT has lower sensitivity than PCR, but a lower cost and shorter test time. In the hospital where this study was conducted, the preadmission COVID-19 test was changed from PCR to RAT on February 24, 2023. This study compared the efficacy of PCR and RAT as the pre-admission COVID-19 test.
Methods:
This was a retrospective observational study comparing two periods, 90 days from November 25, 2022 to February 23, 2023, and 90 days from February 28, 2023 to May 29, 2023. Patients hospitalized from the emergency medical center during these two periods were included. Binomial logistic regression was used to compare the emergency department length of stay (ED LOS) between the two groups (PCR vs. RAT). Logistic regression was used to compare the mortality.
Results:
Four thousand seven hundred and thirty-eight patients were admitted through the emergency room: 2,202 patients in the PCR group and 2,443 patients in the RAT group. No statistically significant differences in the characteristics and severity were observed between the two groups. The mean ED LOS of PCR 5.07 hours (interquartile range, 3.80-6.75) was longer than RAT 3.65 hours (interquartile range, 2.83-4.68) (P<0.001). Mortality was higher in PCR 8.9% than RAT 6.6% (P=0.005).
Conclusion
The study showed that ED LOS and mortality were reduced when using RAT rather than PCR as a preadmission COVID-19 test.
6.Clinical guidelines for the diagnosis, evaluation, and management of hypertension for Korean children and adolescents: the Korean Working Group of Pediatric Hypertension
Se Jin PARK ; Hyo Soon AN ; Sung Hye KIM ; Seong Heon KIM ; Hee Yeon CHO ; Jae Hyun KIM ; Anna CHO ; Ji Hee KWAK ; Jae IL SHIN ; Keum Hwa LEE ; Jin-Hee OH ; Jung Won LEE ; Hae Soon KIM ; Hye-Jung SHIN ; Mi Young HAN ; Myung Chul HYUN ; Tae Sun HA ; Young Hwan SONG ;
Kidney Research and Clinical Practice 2025;44(1):20-48
Pediatric hypertension (HTN) is a significant, growing health concern worldwide and also in Korea. Diagnosis, evaluation, and treatment of HTN in Korean children and adolescents are uncertain due to limitations in using the current international guidelines, since the recommendations by the American Academy of Pediatrics (AAP) and European Society of Hypertension (ESH) guidelines differ. Furthermore, these are guidelines for Western youth, who are racially and ethnically different from Koreans. In addition, reference blood pressure values for all pediatric age groups, which are essential for the diagnosis of HTN according to these two guidelines, are absent in Korea. Therefore, HTN guidelines for Korean children and adolescents should be established. The Korean Working Group of Pediatric Hypertension established clinical guidelines for the diagnosis, evaluation, and management of HTN in Korean children and adolescents. These guidelines were based on reported clinical evidence, expert recommendations, and AAP and ESH guidelines. The characteristics of Korean youth and the Korean medical and insurance system were considered during the establishment of the guidelines. By providing recommendations suitable for Korean youth, these guidelines will help in the prevention and management of childhood HTN, thus relieving the burden of cardiovascular disease in adulthood in Korea.
7.Geriatric risk model for older patients with diffuse large B-cell lymphoma (GERIAD): a prospective multicenter cohort study
Ho-Young YHIM ; Yong PARK ; Jeong-A KIM ; Ho-Jin SHIN ; Young Rok DO ; Joon Ho MOON ; Min Kyoung KIM ; Won Sik LEE ; Dae Sik KIM ; Myung-Won LEE ; Yoon Seok CHOI ; Seong Hyun JEONG ; Kyoung Ha KIM ; Jinhang KIM ; Chang-Hoon LEE ; Ga-Young SONG ; Deok-Hwan YANG ; Jae-Yong KWAK
The Korean Journal of Internal Medicine 2024;39(3):501-512
Background/Aims:
Optimal risk stratification based on simplified geriatric assessment to predict treatment-related toxicity and survival needs to be clarified in older patients with diffuse large B-cell lymphoma (DLBCL).
Methods:
This multicenter prospective cohort study enrolled newly diagnosed patients with DLBCL (≥ 65 yr) between September 2015 and April 2018. A simplified geriatric assessment was performed at baseline using Activities of Daily Living (ADL), Instrumental ADL (IADL), and Charlson’s Comorbidity Index (CCI). The primary endpoint was event-free survival (EFS).
Results:
The study included 249 patients, the median age was 74 years (range, 65-88), and 125 (50.2%) were female. In multivariable Cox analysis, ADL, IADL, CCI, and age were independent factors for EFS; an integrated geriatric score was derived and the patients stratified into three geriatric categories: fit (n = 162, 65.1%), intermediate-fit (n = 25, 10.0%), and frail (n = 62, 24.9%). The established geriatric model was significantly associated with EFS (fit vs. intermediate-fit, HR 2.61, p < 0.001; fit vs. frail, HR 4.61, p < 0.001) and outperformed each covariate alone or in combination. In 87 intermediate-fit or frail patients, the relative doxorubicin dose intensity (RDDI) ≥ 62.4% was significantly associated with worse EFS (HR, 2.15, 95% CI 1.30–3.53, p = 0.002). It was related with a higher incidence of grade ≥ 3 symptomatic non-hematologic toxicities (63.2% vs. 27.8%, p < 0.001) and earlier treatment discontinuation (34.5% vs. 8.0%, p < 0.001) in patients with RDDI ≥ 62.4% than in those with RDDI < 62.4%.
Conclusions
This model integrating simplified geriatric assessment can risk-stratify older patients with DLBCL and identify those who are highly vulnerable to standard dose-intensity chemoimmunotherapy.
8.Comparison of Short-Term Outcomes and Safety Profiles between Androgen Deprivation Therapy+Abiraterone/Prednisone and Androgen Deprivation Therapy+Docetaxel in Patients with De Novo Metastatic Hormone-Sensitive Prostate Cancer
Dong Jin PARK ; Tae Gyun KWON ; Jae Young PARK ; Jae Young JOUNG ; Hong Koo HA ; Seong Soo JEON ; Sung-Hoo HONG ; Sungchan PARK ; Seung Hwan LEE ; Jin Seon CHO ; Sung-Woo PARK ; Se Yun KWON ; Jung Ki JO ; Hong Seok PARK ; Sang-Cheol LEE ; Dong Deuk KWON ; Sun Il KIM ; Sang Hyun PARK ; Soodong KIM ; Chang Wook JEONG ; Cheol KWAK ; Seock Hwan CHOI ;
The World Journal of Men's Health 2024;42(3):620-629
Purpose:
This study aimed to compare the short-term outcomes and safety profiles of androgen-deprivation therapy (ADT)+abiraterone/prednisone with those of ADT+docetaxel in patients with de novo metastatic hormone-sensitive prostate cancer (mHSPC).
Materials and Methods:
A web-based database system was established to collect prospective cohort data for patients with mHSPC in Korea. From May 2019 to November 2022, 928 patients with mHSPC from 15 institutions were enrolled. Among these patients, data from 122 patients who received ADT+abiraterone/prednisone or ADT+docetaxel as the primary systemic treatment for mHSPC were collected. The patients were divided into two groups: ADT+abiraterone/prednisone group (n=102) and ADT+docetaxel group (n=20). We compared the demographic characteristics, medical histories, baseline cancer status, initial laboratory tests, metastatic burden, oncological outcomes for mHSPC, progression after mHSPC treatment, adverse effects, follow-up, and survival data between the two groups.
Results:
No significant differences in the demographic characteristics, medical histories, metastatic burden, and baseline cancer status were observed between the two groups. The ADT+abiraterone/prednisone group had a lower prostate-specific antigen (PSA) progression rate (7.8% vs. 30.0%; p=0.011) and lower systemic treatment discontinuation rate (22.5% vs. 45.0%; p=0.037). No significant differences in adverse effects, oncological outcomes, and total follow-up period were observed between the two groups.
Conclusions
ADT+abiraterone/prednisone had lower PSA progression and systemic treatment discontinuation rates than ADT+docetaxel. In conclusion, further studies involving larger, double-blinded randomized trials with extended follow-up periods are necessary.
9.Real‑time three‑dimensional transthoracic echocardiographic segmental volume analysis:a quantitative and objective tool for assessing regional left ventricle wall motion in patients with ischemic heart disease
Jin‑Hwan KWAK ; Kang‑Un CHOI ; Jong‑Il PARK ; Jong‑Ho NAM ; Chan‑Hee LEE ; Ung KIM ; Jong‑Seon PARK ; Jang‑Won SON
Journal of Cardiovascular Imaging 2024;32(1):40-
Background:
Evaluation of regional left ventricle function using two-dimensional echocardiography (2DE) in patients with ischemic heart disease has limitations due to its low objectivity and qualitative nature. In addition, 2DE is limited because multiple acoustic windows are used to obtain the image, whereas three-dimensional echocardiography (3DE) uses a single window. This study aims to demonstrate the clinical utility of 3DE segmental volume analysis for evaluating regional wall motion abnormality (RWMA).
Methods:
This retrospective study included 33 patients with ischemic heart disease and single-vessel territory RWMA confirmed on coronary angiography. RWMA was visually assessed using 2DE, generating 17-segment bull’s-eye polar maps, and 3DE. In the 3DE study, two independent observers analyzed segmental volumes and segmental volume ejection fractions (SVEFs) using QLAB 3D quantification software. The optimal SVEF cutoff value differentiating normal from abnormal was determined using receiver operating curve analysis. The accuracy of 3DE in predicting culprit coronary arteries was compared with that of 2DE using Cohen κ coefficients, which also were used for interobserver and intraobserver variability assessments.
Results:
Mean 3DE SVEFs were significantly lower in segments showing RWMA on 2DE. The optimal SVEF cutoff value was 44%, with sensitivity of 75.0% and specificity of 73.9% (area under the curve, 0.801; 95% CI, 0.763–0.838; P < 0.001).The reliability of 3DE-derived bull’s-eye predictions of culprit coronary arteries was 81.8% (κ = 0.672; 95% CI, 0.555– 0.789; P < 0.001). Interobserver and intraobserver variabilities were 97.0% (κ = 0.947; 95% CI, 0.894–1.00; P < 0.001) and 93.9% (κ = 0.897; 95% CI, 0.827–0.967; P < 0.001), respectively.
Conclusions
The 3DE segmental volume analysis effectively quantified regional left ventricle function and aligned well with 2DE and coronary angiography findings in predicting culprit coronary arteries. Thus, 3DE segmental volume analysis can serve as a quantitative and objective tool for RWMA assessment in patients with ischemic heart disease.
10.Real‑time three‑dimensional transthoracic echocardiographic segmental volume analysis:a quantitative and objective tool for assessing regional left ventricle wall motion in patients with ischemic heart disease
Jin‑Hwan KWAK ; Kang‑Un CHOI ; Jong‑Il PARK ; Jong‑Ho NAM ; Chan‑Hee LEE ; Ung KIM ; Jong‑Seon PARK ; Jang‑Won SON
Journal of Cardiovascular Imaging 2024;32(1):40-
Background:
Evaluation of regional left ventricle function using two-dimensional echocardiography (2DE) in patients with ischemic heart disease has limitations due to its low objectivity and qualitative nature. In addition, 2DE is limited because multiple acoustic windows are used to obtain the image, whereas three-dimensional echocardiography (3DE) uses a single window. This study aims to demonstrate the clinical utility of 3DE segmental volume analysis for evaluating regional wall motion abnormality (RWMA).
Methods:
This retrospective study included 33 patients with ischemic heart disease and single-vessel territory RWMA confirmed on coronary angiography. RWMA was visually assessed using 2DE, generating 17-segment bull’s-eye polar maps, and 3DE. In the 3DE study, two independent observers analyzed segmental volumes and segmental volume ejection fractions (SVEFs) using QLAB 3D quantification software. The optimal SVEF cutoff value differentiating normal from abnormal was determined using receiver operating curve analysis. The accuracy of 3DE in predicting culprit coronary arteries was compared with that of 2DE using Cohen κ coefficients, which also were used for interobserver and intraobserver variability assessments.
Results:
Mean 3DE SVEFs were significantly lower in segments showing RWMA on 2DE. The optimal SVEF cutoff value was 44%, with sensitivity of 75.0% and specificity of 73.9% (area under the curve, 0.801; 95% CI, 0.763–0.838; P < 0.001).The reliability of 3DE-derived bull’s-eye predictions of culprit coronary arteries was 81.8% (κ = 0.672; 95% CI, 0.555– 0.789; P < 0.001). Interobserver and intraobserver variabilities were 97.0% (κ = 0.947; 95% CI, 0.894–1.00; P < 0.001) and 93.9% (κ = 0.897; 95% CI, 0.827–0.967; P < 0.001), respectively.
Conclusions
The 3DE segmental volume analysis effectively quantified regional left ventricle function and aligned well with 2DE and coronary angiography findings in predicting culprit coronary arteries. Thus, 3DE segmental volume analysis can serve as a quantitative and objective tool for RWMA assessment in patients with ischemic heart disease.

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