1.Reinjection in Patients with Intraocular Inflammation Development after Intravitreal Brolucizumab Injection
Myung Ae KIM ; Soon Il CHOI ; Jong Min KIM ; Hyun Sub OH ; Yong Sung YOU ; Won Ki LEE ; Soon Hyun KIM ; Oh Woong KWON ; Ju Young KIM
Korean Journal of Ophthalmology 2025;39(3):213-221
Purpose:
To investigate the outcomes of brolucizumab reinjection after intraocular inflammation (IOI) development.
Methods:
This retrospective study analyzed patients with brolucizumab injections from April 2021 to January 2024. Patients who developed IOI after brolucizumab were included and categorized into subgroups depending on reinjection, discontinuation, and further IOI development.
Results:
A total of 472 eyes of 432 patients received brolucizumab injections. Thirty-eight cases developed IOI at least once, and 25 continued brolucizumab. Sixteen cases had no more IOI events, and nine experienced a second or more IOI events. Among the nine cases, three maintained brolucizumab injections despite IOI recurrence. The incidence of IOI was 8.1% based on the number of eyes (38 of 472 eyes) and 2.0% based on the number of brolucizumab injections (50 of 2,468 injections). The incidence of occlusive retinal vasculitis was 0.2% (1 of 472 eyes). The recurrence rate was 23.7% (9 of 38 eyes). The average number of injections between the first brolucizumab injection and the injection date on which IOI first developed was 2.15 times in the no-reinjection group, 3.44 times in the no-IOI-recurrence group, and 2.0 times in the second-IOI-episode group. Time to IOI occurrence in cases with first IOI episode was 18.60 ± 16.73 days, with 15 cases developing IOI within 1 week.
Conclusions
This study elucidates the real-world incidence of brolucizumab associated IOIs, with a description of information related to reinjections after the IOI episodes. A comprehensive understanding of brolucizumab reinjection is essential for its optimal utilization.
2.Clinical Efficacy of Ultrafast Dynamic Contrast-Enhanced MRI Using Compressed Sensing in Distinguishing Benign and Malignant Soft-Tissue Tumors
You Seon SONG ; In Sook LEE ; Young Jin CHOI ; Jeung Il KIM ; Kyung-Un CHOI ; Kangsoo KIM ; Kyungeun JANG
Korean Journal of Radiology 2025;26(1):43-53
Objective:
To evaluate the clinical efficacy of ultrafast dynamic contrast-enhanced (DCE)-MRI using a compressed sensing (CS) technique for differentiating benign and malignant soft-tissue tumors (STTs) and to evaluate the factors related to the grading of malignant STTs.
Materials and Methods:
A total of 165 patients (96 male; mean age, 61 years), comprising 111 with malignant STTs and 54 with benign STTs according to the 2020 WHO classification, underwent DCE-MRI with CS between June 2018 and June 2023. The clinical, qualitative, and quantitative parameters associated with conventional MRI were also obtained. During post-processing of the early arterial phase of DCE-MRI, the time-to-enhance (TTE), time-to-peak (TTP), initial area under the curve at 60 s (iAUC60), and maximum slope were calculated. Furthermore, the delayed arterial phase parameters of DCEMRI, including Ktrans , Kep, Ve, and iAUC values and time-concentration curve (TCC) types, were determined. Clinical and MRI parameters were statistically analyzed to differentiate between benign and malignant tumors and their correlation with tumor grading.
Results:
According to logistic regression analysis, the TTE value (P < 0.001) of the early arterial phase and Ve (P = 0.039) and iAUC (P = 0.006) values of the delayed arterial phase, as well as age, location, peritumoral edema, and contrast heterogeneity on conventional MRI, were significant (P = 0.001–0.015) in differentiating benign and malignant tumors. Among all the quantitative parameters, the TTE value had the highest accuracy, with an area under the receiver operating characteristic curve of 0.902. The grading of malignant tumors was significantly correlated with peritumoral edema; CE heterogeneity; visual diffusion restriction; minimum and mean ADC; TTP, Kep, and Ve values; and the TCC graph (all P < 0.05).
Conclusion
Among the quantitative parameters obtained using ultrafast DCE-MRI, early arterial phase TTE was the most accurate for distinguishing between benign and malignant tumors.
3.F‑18 FDG PET/CT Clinical Service Trends in Korea from 2018 to 2022:A National Surveillance Study
Jaesun YOON ; Heejin KIM ; Do Hyun WOO ; Seung Yeop CHAE ; Ji Heui LEE ; Inki LEE ; Ilhan LIM ; Byung Il KIM ; Chang Woon CHOI ; Byung Hyung BYUN
Nuclear Medicine and Molecular Imaging 2025;59(2):117-124
Objectives:
To assess the trends and disparities in the utilization of F-18 fluorodeoxyglucose positron emission tomography/ computed tomography (FDG PET/CT) in Korea between 2018 and 2022, with a focus on disease classification, patient demographics, and regional distribution.
Methods:
This national surveillance retrospective study uses data from the Health Insurance Review and Assessment Service (HIRA) database, which includes all FDG PET/CT examinations conducted in Korea from 2018 to 2022. Disease classifications, cancer types, age groups, gender, and geographic regions were analyzed using descriptive statistics. Utilization rates per 100,000 population were calculated for regional comparisons.
Results:
FDG PET/CT utilization increased by 25.4%, from 174,885 examinations in 2018 to 219,377 in 2022. Older age groups (60 years and above) accounted for the majority of examinations, with males undergoing more examinations than females. Oncology remained the primary indication, with lung, colorectal, and non-Hodgkin lymphoma leading in examination numbers. The number of examinations performed on patients aged 60 and above increased at a higher rate compared to those under 60. Significant geographic disparities were found, with Seoul reporting the highest utilization rate (1,114.3 examinations per 100,000 population), while Gyeongbuk exhibited much lower rate (26.2 examinations per 100,000 population).
Conclusions
This study highlights the growing utilization of FDG PET/CT in Korea, particularly among older adults, with significant gender differences in cancer types. The findings also reveal disparities in FDG PET/CT utilization across regions, indicating varying access to advanced imaging technology.
5.Prevalence and characteristics of impacted teeth in Korean orthodontic patients at ten university dental hospitals
Youn-Kyung CHOI ; Sung-Hun KIM ; Yong-Il KIM ; Seong-Sik KIM ; Soo-Byung PARK ; Dong-Soon CHOI ; Ho-Jin KIM ; Kyung-A KIM ; Mo-Hyeon LEE ; Sung-Hwan CHOI ; Sung-Kwon CHOI ; Kyungmin Clara LEE ; Young-Mi JEON ; Sewoong OH ; Seorin JEONG
The Korean Journal of Orthodontics 2025;55(3):234-241
Objective:
This study aimed to investigate the prevalence and characteristics of impacted teeth (ITs) in orthodontic patients at university dental hospitals in Korea.
Methods:
This study included 14,774 patients who visited the Department of Orthodontics at 10 university dental hospitals in Korea between 2020 and 2022 and underwent orthodontic diagnosis. The prevalence and characteristics of ITs were investigated using orthodontic diagnostic records, radiographs, and diagnostic casts.
Results:
The prevalence of ITs, excluding third molar impaction, in Korean orthodontic patients was 13.6% (n = 2,014).The prevalence of ITs in pediatric orthodontic patients was 24.5% (n = 1,614).Of these patients, 68.2% had one IT, 27.5% had two ITs, 24.3% had bilateral IT, and 75.7% had unilateral IT. The most frequent IT was the maxillary canine (50.1%), followed by the mandibular second molar (11.7%), and maxillary second premolar (9.6%). An abnormal eruption path (46.5%) was the most frequent etiology. Orthodontic traction after surgical exposure (70.6%) was the most frequent treatment option. Among the patients with ITs, 29.8% had other dental anomalies, such as tooth agenesis (8.7%), microdontia (8.0%), and supernumerary teeth (5.1%). Furthermore, 50.8% had complications such as cystic lesions (18.3%), transposition (17.7%), and root resorption (14.8%).Among the patients with maxillary canine impaction, 62.2% had labial maxillary canine impaction and 21.1% had palatal maxillary canine impaction.
Conclusions
The prevalence of ITs in Korean orthodontic patients at university dental hospitals was high, particularly in pediatric orthodontic patients.
6.Effects of clear aligner edentulous space design on distal canine movement: An iterative finite element analysis in cases involving extraction
Seung Eun BAEK ; Kiyean KIM ; Youn-Kyung CHOI ; Sung-Hun KIM ; Seong-Sik KIM ; Ki Beom KIM ; Yong-Il KIM
The Korean Journal of Orthodontics 2025;55(3):193-201
Objective:
Using finite element method (FEM) analysis of a clear aligner (CA), this study aimed to investigate the effects of varying the edentulous space on canine distal bodily movement during space closure following maxillary first premolar extraction.
Methods:
FEM analysis was used to simulate distal canine bodily movement following maxillary first premolar extraction using CAs. Four CA designs for edentulous spaces were compared: no-pontic, full-pontic, halfpontic, and beam. Three-dimensional models of the tooth components and CA were created. The target was set at a 0.25-mm distal canine movement. Long-term tooth movement was simulated using an iterative calculation method.
Results:
All the groups initially showed crown displacement, distal tipping, and distal rotation.Over time, the movement patterns differed in relation to the design. The no-pontic design exhibited the greatest displacement and tipping. The beam design exhibited the largest initial displacement but showed the lowest displacement and tipping thereafter. Full- and half-pontic designs yielded intermediate results. Significant force reduction was observed immediately after CA application, and was followed by a gradual decrease. The mean tooth-movement achievement rate was approximately 76.7%.
Conclusions
The edentulous space design of the CA substantially affected tooth-movement behavior. An iterative simulation is necessary to evaluate longterm tooth-movement patterns. The beam design demonstrated optimal suitability for bodily movement with minimal tipping. For optimal results, additional setup or overcorrection may be necessary.
7.Force and moment analysis of clear aligners: Impact of material properties and design on premolar rotation
Dong-Woo KIM ; Hyun-Jun LEE ; Ki Beom KIM ; Sung-Hun KIM ; Seong-Sik KIM ; Soo-Byung PARK ; Youn-Kyung CHOI ; Yong-Il KIM
The Korean Journal of Orthodontics 2025;55(3):212-223
Objective:
To quantitatively analyze and compare the forces and moments generated by thermoformed polyethylene terephthalate glycol (PETG) and direct-printed TC-85 clear aligners (CAs), with various margin designs, during premolar rotation.
Methods:
In total, 132 CAs were fabricated and divided into four groups (n = 33 per group). Group C consisted of thermoformed PETG aligners with a 2 mm gingival margin. Group E comprised direct-printed TC-85 aligners with equi-gingival margin, whereas Group G utilized direct-printed TC-85 aligners with 2 mm gingival margins.Finally, Group T featured direct-printed TC-85 aligners with an additional 1 mm thickness at the mesial embrasure. The forces and moments were measured using a 6-axis force/moment transducer at 2°, 3°, and 4° of rotation. All measurements were conducted at 37°C to simulate intraoral conditions. Forces were measured in the buccolingual, anteroposterior, and vertical directions, while moments were measured in the mesiodistal, buccolingual, and rotational planes.
Results:
The PETG aligners (Group C) showed significantly increased buccal and posterior force across the rotation angles (P < 0.05), whereas the intrusive force remained consistent. In contrast, the TC-85 aligners maintained consistent forces across all rotation angles.Direct-printed aligners demonstrated significantly lower intrusive forces than PETG aligners (P < 0.001). Group T exhibited reduced unwanted forces while maintaining effective rotational moments. Furthermore, all direct-printed aligners showed more predictable force delivery patterns than thermoformed aligners.
Conclusions
Direct-printed TC-85 aligners demonstrated superior force consistency and reduced unwanted side effects compared with traditional PETG aligners. Although marginal design modifications did not significantly improve rotational efficiency, they effectively reduced unwanted intrusive forces.
8.Mortality and Risk Factors for Emphysematous Pyelonephritis in Korea: A Multicenter Retrospective Cohort Study
Seung-Kwon CHOI ; Jeong Woo LEE ; Seung Il JUNG ; Eu Chang HWANG ; Joongwon CHOI ; Woong Bin KIM ; Jung Sik HUH ; Jin Bong CHOI ; Yeonjoo KIM ; Jae Min CHUNG ; Ju-Hyun SHIN ; Jae Hung JUNG ; Hong CHUNG ; Sangrak BAE ; Tae-Hyoung KIM
Urogenital Tract Infection 2025;20(1):34-41
Purpose:
Emphysematous pyelonephritis (EPN) is a life-threatening disease requiring immediate treatment. This multicenter retrospective cohort study aimed to analyze the mortality rate and risk factors associated with EPN.
Materials and Methods:
Between January 2011 and February 2021, 217 patients diagnosed with EPN via computed tomography who visited 14 teaching hospitals were retrospectively analyzed. Clinical data, including age, sex, comorbidities, Huang and Tseng classification, hydronephrosis, acute kidney injury, blood and urine tests, surgical interventions, percutaneous drainage, and conservative treatments, were compared between the survival and death groups. Risk factors for mortality due to EPN were analyzed using univariate and multivariate methods.
Results:
The mean age of survivors and deceased patients was 67.8 and 69.0 years, respectively (p=0.136). The sex distribution (male/female) was 48/146 and 8/15, respectively (p=0.298). Of the 217 patients, 23 died, resulting in a mortality rate of 10.6%. In univariate analysis, the Huang and Tseng classification (p=0.004), platelet count (p=0.005), and acute kidney injury (p=0.007) were significantly associated with mortality from EPN. In multivariate analysis, only the Huang and Tseng classification (p=0.029) was identified as a risk factor. Mortality rates according to the Huang and Tseng classification were as follows: class I (5.88%), class II (7.50%), class IIIa (14.28%), class IIIb (25.00%), and class IV (23.07%).
Conclusions
EPN is associated with a high mortality rate. Among various clinical factors, the Huang and Tseng classification was the most significant indicator for predicting mortality.
9.Synergistic effects of L-arginine and argininosuccinate synthetase 1 in inducing apoptosis in hepatocellular carcinoma
Jin Sun KIM ; Won-Mook CHOI ; Ha-Il KIM ; Sung Won CHUNG ; Jonggi CHOI ; Danbi LEE ; Kang Mo KIM
Journal of Liver Cancer 2025;25(1):79-90
Background:
s/Aims: Hepatocellular carcinoma (HCC) is a malignant cancer with an increasing incidence worldwide. Although numerous efforts have been made to identify effective therapies for HCC, current strategies have limitations. We present a new approach for targeting L-arginine and argininosuccinate synthetase 1 (ASS1).
Methods:
ASS1 expression in HCC cell lines and primary hepatocytes was detected using polymerase chain reaction and western blotting. Proliferation, migration, signaling pathways, and nitric oxide production in HCC cell lines were measured using MTS, colony formation, wound healing, Western blot, and Griess assays.
Results:
ASS1 expression varied among the HCC cell lines, and cisplatin cytotoxicity was ASS1-dependent. L-arginine alone induced apoptosis in HCC cell lines, regardless of ASS1 expression; however, its effect was enhanced in ASS1-expressing HCC cell lines. Cisplatin cytotoxicity also increased, suggesting that L-arginine acts as a sensitizer to cisplatin in HCC cell lines. ASS1 and L-arginine produced nitric oxide and inhibited key proliferation- and survival-related signaling pathways such as PI3K/Akt and MAPK. Additionally, ASS1 and L-arginine reduced the expression of PKM1 and PKM2 in the glycolysis pathway.
Conclusions
Our study revealed that ASS1 and L-arginine exhibited anticancer effects in HCC and sensitized cisplatin-resistant HCC cells to chemotherapy. The combination of ASS1 and L-arginine significantly enhanced the anticancer effects, even in HCC cell lines with low or absent ASS1 expression. These findings highlight the critical roles of arginine and ASS1 in HCC and suggest that increasing arginine availability could be a promising therapeutic strategy.
10.Randomized Multicenter Study to Evaluate the Efficacy and Safety of Fexuprazan According to the Timing of Dosing in Patients With Erosive Esophagitis
Sang Pyo LEE ; In-Kyung SUNG ; Oh Young LEE ; Myung-Gyu CHOI ; Kyu Chan HUH ; Jae-Young JANG ; Hoon Jai CHUN ; Joong-Goo KWON ; Gwang Ha KIM ; Nayoung KIM ; Poong-Lyul RHEE ; Sang Gyun KIM ; Hwoon-Yong JUNG ; Joon Seong LEE ; Yong Chan LEE ; Hye-Kyung JUNG ; Jae Gyu KIM ; Sung Kook KIM ; Chong-il SOHN
Journal of Neurogastroenterology and Motility 2025;31(1):86-94
Background/Aims:
Fexuprazan, a novel potassium-competitive acid blocker, was developed for treating acid-related disorders. Pharmacokinetic and pharmacodynamic properties of fexuprazan, unlike those of proton pump inhibitors, are independent of food effect. This study aims to evaluate differences in efficacy and safety of fexuprazan in patients with erosive esophagitis (EE) according to the timing of dosing.
Methods:
In this multicenter, open-label noninferiority study, patients who had typical reflux symptoms with endoscopically confirmed EE were randomized 1:1 to receive fexuprazan 40 mg daily 30 minutes before or after meal. Treatment was completed after 2 weeks or 4 weeks when healing was endoscopically confirmed. The primary endpoint was the proportion of patients with healed EE confirmed by endoscopy up to week 4. Safety endpoints included treatment-emergent adverse events (TEAEs).
Results:
In the prior-to-meal group (n = 89) and after-meal group (n = 86), 4-week EE healing rates were 98.77% and 100.00% (difference, 0.01%; 95% CI, –0.01% to 0.04%) and 2-week EE healing rates were 95.77% and 97.14% (difference, 0.01%; 95% CI, –0.05% to 0.07%), respectively. TEAEs were 9.78% and 8.70% in the prior-to-meal group and the after-meal group, respectively.
Conclusions
Non-inferiority analysis revealed that taking fexuprazan after meal was non-inferior to taking fexuprazan before meals in patients with EE. The frequency of adverse events was similar between the 2 study groups. The drug is safe and effective for healing EE regardless of the timing of dosing.

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