1.Posterior Cerebral Artery Territory Infarction after Bilateral Carotid Artery Stenting
Hyunjun BAE ; Hyesu YUN ; Moses LEE ; Jaemin SHIN ; Keon-Joo LEE ; Chi Kyung KIM ; Kyungmi OH ; Sangil SUH ; Kyubong LEE
Journal of the Korean Neurological Association 2026;44(2):168-172
Carotid artery stenting (CAS) is considered for patients with symptomatic carotid stenosis of 50% or greater. Following CAS, hemodynamic changes can alter the cerebral perfusion status. Furthermore, hypotension and bradycardia may occur due to the stimulation of carotid sinus baroreceptors. A more meticulous approach to these hemodynamic changes is required, especially in patients with bilateral carotid artery stenosis and concurrent multiple cerebrovascular stenoses. This report presents a case of posterior cerebral artery territory infarction that occurred after bilateral CAS.
2.Diagnostic Accuracy of Serological Tests for Mycoplasma pneumoniae Infections in Children with Pneumonia, Based on Symptom Onset
Gahee KIM ; Ki Wook YUN ; Dayun KANG ; Taek Jin LEE ; Byung Wook EUN ; Hyunju LEE ; Yae-Jean KIM ; Doo Ri KIM ; Areum SHIN ; Hyun Mi KANG ; Ye Ji KIM ; Byung Ok KWAK ; Younghee LEE ; Ye Kyung KIM ; Young June CHOE ; Woosuck SUH ; Kyo Jin JO ; Kyung-Ran KIM ; Eun Young CHO ; Kyung Min KIM ; Joon Kee LEE ; Su Eun PARK
Annals of Laboratory Medicine 2026;46(2):162-170
Background:
Mycoplasma pneumoniae is a major cause of community-acquired pneumonia (CAP) in children, with a rising incidence of macrolide resistance. Early diagnosis is crucial for reducing the disease burden; however, current diagnostic tools have limitations.We evaluated the diagnostic accuracy of serological assays and their performance based on symptom onset in children with CAP.
Methods:
From September 2023 to September 2024, we prospectively enrolled children with CAP, classified as M. pneumoniae pneumonia (MPP) or non-MPP, from 16 hospitals in Korea. Serological testing included chemiluminescence immunoassay (CLIA) and ELISA for detecting IgM and IgG, along with particle agglutination (PA) for total antibody measurements. Serological responses were analyzed at different times after symptom onset (0–4, 5–9, and 10–21 days).
Results:
Among 472 children with CAP (362 MPP, 110 non-MPP), 138 (29.2%) underwent PA testing, and 334 (70.8%) underwent IgM testing. PA at a 1:640 cutoff showed 48.0% sensitivity and 100% specificity. CLIA and ELISA showed comparable sensitivities (69.1% vs. 69.2%) and specificities (76.9% vs. 66.7%) for IgM testing. Seropositivity increased significantly with time since symptom onset (P for trend < 0.001), reaching 97.9% for IgM, 62.5% for IgG, and 94.7% for PA at 10–21 days.
Conclusions
The time post-symptom onset significantly influenced the diagnostic utility of serological tests for pediatric MPP, which showed limited value during the early stage of illness. These findings emphasize the importance of symptom onset-based interpretation of serological test results and their utility in complementing PCR when optimizing MPP diagnosis in children.
3.Periarticular Osteoid Osteoma of the Calcaneus: A Case Report
Kyeong Baek KIM ; Jung Yun BAE ; Suk-Woong KANG ; Won Chul SHIN ; Sang-Min LEE ; Seung Hun WOO
Journal of Korean Foot and Ankle Society 2026;30(2):80-85
Osteoid osteoma accounts for approximately 10% of all benign bone tumors, but only approximately 4% of cases occur in the foot and ankle area. Periarticular osteoid osteoma frequently manifests with nonspecific clinical symptoms that mimic other conditions, potentially leading clinicians down a diagnostic side path and resulting in delayed or missed diagnoses compared to extra-articular osteoid osteoma. Although plain radiographs may show nonspecific findings, magnetic resonance imaging can detect bone marrow edema and surrounding soft tissue changes. Computed tomography is the most accurate modality for diagnosis. This paper reports the case of a 26-year-old female diagnosed with periarticular osteoid osteoma of the calcaneus and was treated with arthroscopic localized curettage at the author’s institution.
4.Prevalence of HER2-ultralow breast cancer in South Korea: a multicenter study by reassessment of HER2-zero cases
Min Chong KIM ; Eun Yoon CHO ; Hee Jin LEE ; Ji Shin LEE ; Jee Yeon KIM ; Wan Seop KIM ; Chungyeul KIM ; Sun-Young JUN ; Hye Jeong CHOI ; So Mang LEE ; Ahrong KIM ; Ji-Young KIM ; Jeong Yun SHIM ; Gyungyub GONG ; Young Kyung BAE
Journal of Pathology and Translational Medicine 2026;60(2):184-192
This study aimed to determine the prevalence of human epidermal growth factor receptor 2 (HER2)–ultralow breast cancer among cases initially classified as HER2 immunohistochemistry (IHC) 0 and assess interobserver variability in interpreting low-level HER2 expression. Methods: In this multicenter retrospective study, all invasive breast cancer cases diagnosed between January and December 2022 across 10 Korean institutions were retrieved. Institutional pathologists reexamined HER2 IHC slides originally reported as IHC 0 according to the 2018 American Society of Clinical Oncology/College of American Pathologists guidelines and reclassified them as HER2-null (0), HER2-ultralow (0+), or HER2-low (1+). Slides from 10% of HER2-null and HER2-ultralow cases were digitized for central review and independently assessed by two pathologists, with discrepancies resolved by consensus. Results: Among 8,026 cases, 2,836 cases (35.5%) were initially reported as IHC 0. Upon re-review, 1,673 (59.0%), 1,139 (40.2%), and 24 (0.8%) cases were reclassified as HER2-null, HER2-ultralow, and HER2-low, respectively. The prevalence of HER2-ultralow breast cancer varied considerably across institutions (23.7%–78.1%). Central review of 268 digitized cases showed concordance in 193 cases (72.0%). Among the 75 discordant cases, 54 tumors (72.0%) were upgraded from HER2-null to HER2-ultralow, and 18 (24.0%) tumors were upgraded from HER2-ultralow to HER2-low. Furthermore, two tumors (2.7%) were downgraded from HER2-ultralow to HER2-null. Conclusions: Approximately 40% of cases initially categorized as IHC 0 were reclassified as HER2-ultralow. The substantial inter-institutional variability observed in interpreting low-level HER2 expression highlights the need for standardized training and quality assurance to ensure accurate identification of patients eligible for HER2-targeted antibody–drug conjugates.
5.Myopia Management Consensus Statement in South Korean Children 2025 by the Korean Myopia Society for the Korean Association for Pediatric Ophthalmology and Strabismus
Yeon-Hee LEE ; Jae Yun SUNG ; Sun Young SHIN ; Young-Woo SUH ; Ungsoo Samuel KIM ; Hyunkyung KIM ; Kyung-Ah PARK ; Su Jin KIM ; MiRae KIM ; Hyun Jin SHIN ; Kyeong Wook LEE ; Haeng-Jin LEE ; So Young HAN ; Jinu HAN ; Eun Hee HONG ; Seung-Hee Hannah BAEK ; Hae Jung PAIK ;
Korean Journal of Ophthalmology 2026;40(2):185-205
Myopia, particularly high myopia, is a significant risk factor for several ocular pathologies including cataract, glaucoma, and retinal detachment. Excessive axial elongation associated with high myopia can induce biomechanical stretching, increasing the risk of serious complications like posterior staphyloma and myopic maculopathy. Global meta-analyses estimate that approximately 10 million people were visually impaired due to myopic maculopathy in 2015, with 3 million being blind. Recent nationwide surveys in South Korea revealed a prevalence of 65.4% for myopia and 6.9% for high myopia in children and adolescents, highlighting the urgent need for effective management. Delaying the onset and slowing the progression of myopia during childhood and adolescence is crucial for reducing the potential lifetime risk of these complications. This consensus statement, prepared by the Korean Myopia Society for the Korean Association for Pediatric Ophthalmology and Strabismus (KAPOS), reviews the current evidence for myopia control interventions and provides management strategies applicable to the South Korean clinical setting. Key interventions covered include lifestyle modifications (outdoor time, near work adjustment), optical methods (myopia-control spectacle lenses, dual-focus soft contact lenses, orthokeratology), and pharmacologic treatment (low-concentration atropine), as well as combination therapies. The statement also addresses patient selection, treatment outcome evaluation using spherical equivalent and axial length changes, and the crucial aspects related to treatment cessation and the rebound effect.
6.Survival Rates of Patients with Gastric Cancer According to Age and Sex: A Large-Scale Study Using Data from 14,739 Patients
Yonghoon CHOI ; Nayoung KIM ; Ji Hyun KIM ; Hyeong Ho JO ; Hyeon Jeong OH ; Hye Seung LEE ; Yu Kyung JUN ; Hyuk YOON ; Cheol Min SHIN ; Young Soo PARK ; Dong Ho LEE ; So Hyun KANG ; Young Suk PARK ; Sang-Hoon AHN ; Yun-Suhk SUH ; Do Joong PARK ; Hyung Ho KIM ; Ji-Won KIM ; Jin Won KIM ; Keun-Wook LEE ; Won CHANG ; Yoon Jin LEE ; Kyoung Ho LEE ; Young Hoon KIM
Cancer Research and Treatment 2026;58(1):252-263
Purpose:
The male predominance in the incidence of gastric cancer (GC) is established; however, sex differences in the prognosis of GC remain controversial. As such, this study analyzed the prognosis of patients with GC based on age and sex.
Materials and Methods:
Data from 14,739 patients diagnosed with GC at Seoul National University Bundang Hospital between 2003 and 2023 were analyzed. Baseline characteristics, histological types of GC, overall and GC-specific survival rates (age and stage stratification), and associated risk factors were analyzed.
Results:
Females were significantly younger (p < 0.001) and exhibited more gastric body cancers (p < 0.001) and tumors with diffuse-type or poorly differentiated histology (p < 0.001) than males. Females exhibited an advantage over males in terms of overall survival (p=0.004), but not in GC-specific survival. However, age stratification revealed significant sex differences, that females < 50 years of age exhibited survival disadvantages (p < 0.001); however, this trend was reversed with age, and females > 60 years exhibited survival advantages (p < 0.001) for both overall and GC-specific survival. This may be explained by the lower ratio of diffuse-type GC as females age. Furthermore, in the analysis according to stage, females with stage IV disease exhibited significant survival disadvantages, with significantly younger age and a higher proportion of diffuse-type GC which exhibits aggressive features, resulting in poorer survival than in males.
Conclusion
Age and stage stratification revealed significant differences in survival between the sexes, which can be helpful for public health strategies.
7.Psychometric Properties of the Mixed State Severity Index for Patients With Mood Disorder
Woojae MYUNG ; Hyeona YU ; Hyo Shin KANG ; Daseul LEE ; Junwoo JANG ; Jakyung LEE ; Joohyun YOON ; Yun Seong PARK ; Hyun A RYOO ; Ye Rim KIM ; Kwang Ho PARK ; Chan Woo LEE ; Yoonjeong JANG ; Kimyoung KIM ; Nara LEE ; Sanghoon HONG ; Hong-Hee WON ; Tae Hyon HA ; Jungkyu PARK
Psychiatry Investigation 2026;23(1):106-117
Objective:
This study aimed to develop a reliable and valid Mixed State Severity Index (MSSI) to assess mood instability in patients with mood disorders and determine cutoff scores.
Methods:
Twenty-one items were selected based on Koukopoulos’ criteria for mixed depressive episode, historically referred to as agitated depression, and Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition, Text Revision mixed features criteria. The MSSI was administered to 242 patients (major depressive disorder [n=92], bipolar disorder [BD] I [n=78], and BD II [n=72]) and 726 controls.
Results:
The MSSI demonstrated high internal consistency (α=0.78–0.90). Exploratory factor analysis revealed a stable four-factor structure. Based on receiver operating characteristic analysis, optimal cutoff scores were identified to distinguish mood disorder groups from controls, ranging from 19.5 to 27.5 depending on diagnosis.
Conclusion
The MSSI is a reliable and valid instrument for assessing the severity of mixed features in patients with mood disorders. The established cutoff scores enhance its clinical utility, providing robust diagnosis and treatment planning support.
8.A Comparative Study of Three National Surveys on Biliary Atresia by the Korean Association of Pediatric Surgeons
Yeon Jun JEONG ; Dayoung KO ; Hyunhee KWON ; Ki Hoon KIM ; Dae Yeon KIM ; Soo-Hong KIM ; Wontae KIM ; Hae-Young KIM ; Hyun Young KIM ; Seong Chul KIM ; Younghyun NA ; Jung-Man NAMGOONG ; So Hyun NAM ; Junbeom PARK ; Jinyoung PARK ; Tae-Jun PARK ; Jeong-Meen SEO ; Ji-Young SUL ; Joonhyuk SON ; Hyun Beak SHIN ; Joohyun SIM ; Soo Min AHN ; Hee Beom YANG ; Jung-Tak OH ; Chaeyoun OH ; Joong Kee YOUN ; Sanghoon LEE ; Ju Yeon LEE ; Kyong IHN ; Hye Kyung CHANG ; Eunyoung JUNG ; Jae Hee CHUNG ; Yu Jeong CHO ; Yun Mee CHOE ; Soo Jin Na CHOI ; Seok Joo HAN ; In Geol HO ; Ji-Won HAN
Advances in Pediatric Surgery 2025;31(2):47-58
Purpose:
Biliary atresia (BA) is a rare but progressive cholangiopathy and the leading cause of pediatric liver transplantation worldwide. The Korean Association of Pediatric Surgeons (KAPS) has conducted three national surveys (2001, 2011, and 2023) to assess long-term trends in the diagnosis, treatment, and outcomes of BA. This study provides a comparative analysis of the 2nd and 3rd national surveys, with reference to selected findings from the 1st survey.
Methods:
This study included 453 patients from the 3rd national survey (2011–2021) and 435 patients from the 2nd survey (2001–2010), all of whom underwent Kasai portoenterostomy. Data were collected via electronic case report forms from pediatric surgical centers nationwide. Comparisons were made regarding demographics, clinical features, diagnostic patterns, operative details, follow-up outcomes, and survival. Kaplan–Meier analysis was used to evaluate long-term survival.
Results:
The mean number of BA patients per year remained stable between surveys (43.5 in the 2nd, 41.18 in the 3rd), though centralization of care increased, with 61.5% of cases managed by two major institutions in the 3rd survey. The median age at surgery decreased, and the use of preoperative imaging (especially magnetic resonance cholangiopancreatography) increased. The 10-year native liver survival rate declined from 59.8% to 53.7%, while overall 10-year survival improved slightly (92.9% to 93.2%). Postoperative complications, such as cholangitis and liver failure, persisted but were better categorized. The 3rd survey also reported improved mortality (4.9%) and reduced follow-up loss (11.5%) compared to the 2nd survey.
Conclusion
While overall survival after Kasai operation has remained high and even improved, native liver survival has slightly declined. The findings reflect earlier diagnosis, more consistent diagnostic imaging, and increasing centralization of care. These trends underscore the importance of long-term nationwide data collection in guiding future strategies for BA management in Korea.
9.Effects of prune consumption on the incidence of low anterior resection syndrome: a randomized controlled trial
Dae Hee PYO ; Jung Kyong SHIN ; Jung Wook HUH ; Hee Cheol KIM ; Seong Hyeon YUN ; Woo Yong LEE ; Yoonah PARK ; Yong Beom CHO
Annals of Coloproctology 2025;41(6):510-518
Purpose:
Low anterior resection syndrome (LARS) is common and devastating complication for patients with rectal cancer who have undergone sphincter-sparing surgery. Prunes are a fiber-rich fruit being effective in treating chronic constipation. The aim of this study was to investigate the effect of prune consumption on the incidence of LARS.
Methods:
A prospective, double-arm, parallel, nonblinded, randomized controlled trial was conducted from September 2019 to March 2021 at a single tertiary center for patients who underwent low anterior resection. Patients randomized to the prune group consumed prune daily for 2 weeks after surgery, while those in the no-prune group did not. The primary outcome was the incidence of major LARS at 3 weeks after surgery.
Results:
A total of 130 patients were randomized and 118 completed the study (81 men, 37 women), including 55 patients (46.6%) in the prune group and 63 patients (53.4%) in the no-prune group. LARS was confirmed in 15 patients (27.3%) in the prune group and 47 patients (74.6%) in the no-prune group (P<0.001). The incidence of major LARS was also significantly lower in the prune group (18.2% vs. 61.9%, P<0.001). Multivariable analysis showed that the level of anastomosis and prune consumption were significantly associated with the incidence of LARS. The prune group had higher emotional scores and lower symptom scores for constipation, sleep disturbance, and loss of appetite in the quality-of-life questionnaire.
Conclusion
Prune consumption significantly reduced the incidence of LARS and improved quality of life after low anterior resection.Trial registration: CRIS identifier: KCT0006085 (registered on September 1, 2019).
10.Is presumed clinical stage I endometrial cancer using PET-CT and MRI accurate in predicting surgical staging?
Ki Eun SEON ; Yoori SHIN ; Jung-Yun LEE ; Eun Ji NAM ; Sunghoon KIM ; Young Tae KIM ; Sang Wun KIM
Journal of Gynecologic Oncology 2025;36(2):e25-
Objective:
To evaluate upstaging, lymph node (LN) metastasis, and recurrence in patients with presumed stage I endometrial cancer using preoperative magnetic resonance imaging (MRI) and positron emission tomography-computed tomography (PET-CT).
Methods:
Retrospective review of 422 patients with presumed clinical stage I endometrial cancer diagnosed via MRI and PET-CT (July 2014–June 2023). Surgical staging included pelvic lymph nodes (PLNs) and para-aortic lymph nodes (PALNs), classifying patients as low/ intermediate- or high-risk groups.
Results:
Post-operative upstaging rate was 14.5% (8.8% low/intermediate-risk vs. 22.8% high-risk, p<0.001). LN metastasis occurred in 5.5% of patients (2.0% low/intermediaterisk vs. 10.5% high-risk, p<0.001), with a dual imaging negative predictive value of 0.945.PLN metastasis was 4.5% (2.0% low/intermediate vs. 8.2% high-risk, p=0.003), and PALN metastasis was 2.6% (0.4% low/intermediate-risk vs. 5.8% high-risk, p=0.001). In low/ intermediate-risk group: tumors ≤2cm had 1.1% LN metastasis rate, endometrium-limited 0.8%, and ≤2cm with endometrium-limited 0.9%. Deep myometrial invasion (odds ratio [OR]=4.4; 95% confidence intervals [CIs]=1.6–12.4) and tumor size >2 cm on MRI (OR=2.9;95% CI=0.8–9.9) increased LN metastasis risk. Median 48.5-month follow-up showed an 8.1% overall recurrence rate (4.0% low/intermediate-risk vs. 14.0% high-risk, p<0.001), with 2.4% nodal recurrences (1.2% low/intermediate-risk vs. 4.1% high-risk).
Conclusion
High-risk patients had significant upstaging, LN metastasis, and recurrence rates. Even in low/intermediate-risk groups, some patients exhibited LN metastasis and nodal recurrence, underscoring the importance of comprehensive surgical staging, including PALN evaluation, for precise diagnosis and treatment.

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