Purpose: To compare the myopic progression between pateints only wearing glasses (Myopia group) and patients using low-dose atropine with glasses (Atropine group) for 1 years or more. Methods: Medical records were retrospectively reviewed. Low-dose atropine (atropine sulfate 0.125%) and artificial tear eyedrops (sodium hyaluronate 0.1%) were applied immediately afterwards to both eyes daily to the Atropine group. All children regularly visited our clinic for measurement of refractive power, axial length, near-point accomodation, pupil diameter, symptoms (glare, near-work disturbance, headache, allergic reaction, dryness) were recorded. Results: A total of 240 patients were included. Atropine was prescribed for 138 patients, the Atropine group, and the remaining 102 patients constituted the Myopia group, and were observed for 20.3 ± 7.8 months. In the initial visit, the mean refractive power was -4.2 ± 1.4 diopters (D) for the Myopia group, -4.8 ± 1.9 D for the Atropine group, and the mean axial length was 24.5 ± 0.6 mm for the Myopia group, 25.1 ± 0.9 mm for the Atropine group. During follow up, in the Myopia group, mean refractive power changed -0.10 ± 0.12 D/month, and mean axial length changed 0.06 ± 0.01 mm/month. In the Atropine group, mean refractive power changed -0.03 ± 0.04 D/month, and mean axial length changed 0.02 ± 0.02 mm/month. The pupil size of the Atropine group was 6.1 ± 0.8 mm, with 30 patients presenting symptoms. Conclusions Refractive power progression and axial length elongation was significantly lesser in the Atropine group than the Myopic group. Pupil diameter increased in the Atropine group, and 21% of the Atropine group complained of symptoms. Using low-dose atropine for more than 1 year was effective to suppress refractive power progression and axial length elongation.

Background: Femoral neck fractures need to be treated in their early stages with accurate reduction and stable fixation to reduce complications. The authors compared the early radiologic outcomes of femoral neck fractures treated with the recently introduced Femoral Neck System (FNS, Depuy-Synthes) with conventional cannulated screws (CS) in a multicenter design. Furthermore, the factors associated with early failure after FNS were analyzed. Methods: The FNS group included 40 patients treated between June 2019 and January 2020, and the CS group included 65 patients treated between January 2015 and May 2019. The operation was performed in 3 university hospitals. Patient demographics, fracture classification, postoperative reduction quality, sliding distance of FNS or CS, union and time to union, and complication rates were examined. Logistic regression analysis was performed on candidate factors for early failure of the FNS group. Results: The FNS group had a 90% union rate and a mean time to union of 4.4 months, while the CS group had similar results with an 83.1% union rate and a mean time to union of 5.1 months. In the subgroup analysis of Pauwels type III fractures, the union rates were 75.0% and 58.8% in the FNS and CS groups, respectively, and the time to union was significantly shorter in the FNS group with 4.8 months compared to 6.8 months in the CS group. Early failure rate within 6 months of FNS fixation was observed to be 10%, which included 3 reduction failures and 1 excessive sliding with a broken implant. Risk factors for early failure after FNS were identified as displaced fractures (Garden classification type III or IV), poor reduction quality, longer tip-apex distance, greater sliding distance, and 1-hole implants, of which sliding distance was the only significant risk factor in multivariate analysis. Conclusions In femoral neck fractures, FNS and CS did not show significant differences for short-term radiologic results. FNS resulted in shorter operative time than cannulated screw fixation and favorable outcomes in Pauwels type III femoral neck fractures.The FNS could be considered a reliable and safe alternative to CS when treating femoral neck fractures.

Background/Aims: Standard triple therapy (STT; proton pump inhibitor [PPI]+clarithromycin+amoxicillin) used for Helicobacter pylori (H. pylori) eradication has shown low treatment success rates in recent years, which is most likely attributable to increased clarithromycin resistance. In this study, we compared treatment success rates of tailored therapy (TT) using real-time polymerase chain reaction (RT-PCR) and empirical STT. Methods: This retrospective study included 650 patients with H. pylori infection, who visited Eunpyeong St. Mary’s Hospital in Korea; 343 patients received TT based on RT-PCR assays, and 307 patients received STT. Eradication success was defined as a negative 13C-urea breath test result 4~8 weeks after treatment completion. Patients who failed first-line therapy and those with clarithromycin resistance received bismuth-containing quadruple therapy (BQT; PPI+bismuth+metronidazole+tetracycline). Results: Intention-to-treat analysis showed that H. pylori eradication rates were higher in patients who received RT-PCR–based TT than in those who were treated using empirical STT (80.5% [190/236] vs. 70.4% [216/307], P=0.069). Per-protocol (PP) analysis showed similar results (84.4% [190/225] vs. 74.7% [216/289], P=0.007). PP analysis showed that 7-day TT treatment was associated with a higher eradication rate than that observed with 10- to 14-day STT (85.2% [178/209] vs. 73.8% [59/80], P=0.029). The clarithromycin resistance rate was 27.9% (87/312). The eradication success rate was 89.2% (74/83) in patients with clarithromycin resistance, who received BQT as first-line therapy. Conclusions The treatment success rate was higher in patients who received 7-day RT-PCR–based TT than in those who were administered 10- to 14-day empirical treatment.

Background and Objectives: Pulmonary arterial hypertension (PAH) is a rare but fatal disease. Recent advances in PAH-specific drugs have improved its outcomes, although the healthcare burden of novel therapeutics may lead to a discrepancy in outcomes between developing and developed countries. We analyzed how the epidemiology and clinical features of PAH has changed through the rapidly advancing healthcare infrastructure in South Korea. Methods: PAH was defined according to a newly devised 3-component algorithm. Using a nationwide health insurance claims database, we delineated annual trends in the prevalence, incidence, medication prescription pattern, and 5-year survival of PAH in Korea. Cumulative survival and potential predictors of mortality were also assessed among 2,151 incident PAH cases. Results: Between 2002 or 2004 and 2018, the prevalence and incidence of PAH increased 75-fold (0.4 to 29.9 per million people) and 12-fold (0.5 to 6.3 per million person-years), respectively. The proportion of patients on combination PAH-specific drug therapy has also steadily increased up to 29.0% in 2018. Among 2,151 incident PAH cases (median [interquartile range] age, 50 [37–62] years; 67.2% female), the 5-year survival rate and median survival duration were 71.8% and 13.1 years, respectively. Independent predictors of mortality were age, sex, etiology of PAH, diabetes, dyslipidemia, and chronic kidney disease. Conclusions This nationwide study delineated that the prevalence and incidence of PAH have grown rapidly in Korea since the early 2000s. The use of combination therapy has also increased, and the 5-year survival rate of PAH in Korea was similar to those in western countries.

Purpose: K-MASTER project is a Korean national precision medicine platform that screened actionable mutations by analyzing next-generation sequencing (NGS) of solid tumor patients. We compared gene analyses between NGS panel from the K-MASTER project and orthogonal methods. Materials and Methods: Colorectal, breast, non–small cell lung, and gastric cancer patients were included. We compared NGS results from K-MASTER projects with those of non-NGS orthogonal methods (KRAS, NRAS, and BRAF mutations in colorectal cancer [CRC]; epidermal growth factor receptor [EGFR], anaplastic lymphoma kinase [ALK] fusion, and reactive oxygen species 1 [ROS1] fusion in non–small cell lung cancer [NSCLC], and Erb-B2 receptor tyrosine kinase 2 (ERBB2) positivity in breast and gastric cancers). Results: In the CRC cohort (n=225), the sensitivity and specificity of NGS were 87.4% and 79.3% (KRAS); 88.9% and 98.9% (NRAS); and 77.8% and 100.0% (BRAF), respectively. In the NSCLC cohort (n=109), the sensitivity and specificity of NGS for EGFR were 86.2% and 97.5%, respectively. The concordance rate for ALK fusion was 100%, but ROS1 fusion was positive in only one of three cases that were positive in orthogonal tests. In the breast cancer cohort (n=260), ERBB2 amplification was detected in 45 by NGS. Compared with orthogonal methods that integrated immunohistochemistry and in situ hybridization, sensitivity and specificity were 53.7% and 99.4%, respectively. In the gastric cancer cohort (n=64), ERBB2 amplification was detected in six by NGS. Compared with orthogonal methods, sensitivity and specificity were 62.5% and 98.2%, respectively. Conclusion The results of the K-MASTER NGS panel and orthogonal methods showed a different degree of agreement for each genetic alteration, but generally showed a high agreement rate.

Purpose: We analyzed the effects of low-dose atropine on myopic progression in elementary schoolchildren aged 6-11 years. Methods: Medical records were retrospectively reviewed before and after 6 months of low-dose atropine eyedrops. Myopia was defined as a spherical equivalent < -1 diopter. Low-dose atropine eyedrops (atropine sulfate 0.125% [w/v]) and artificial tear eyedrops (sodium hyaluronate 0.1% [w/v]) immediately afterwards were applied to both eyes daily, and all children regularly visited us for measurement of refractive power, axial length, pupil diameter, and near-point accommodation. symptoms (headache, light sensitivity, near-work disturbance, allergic reaction, dry eye, and poor night vision) were recorded. Results: A total of 116 patients were included. Atropine was prescribed for 65 patients, the remaining 51 patients constituted the control group. In the atropine group, the mean age was 10.2 ± 1.8 years and 23 patients (35.4%) were male. At the initial visit, the mean refractive power was -4.7 ± 2.1 diopters (D) (-1.0 to -10.5) and the mean axial length was 24.95 ± 1.02 mm (22.58-27.99). At the 6-month follow-up, the change of refractive power was -0.9 ± 1.1 D (-0.75 to -4.75) and the change of axial length was 0.47 ± 0.39 mm (0.01-1.6). However, 6 months after application of low-dose atropine eyedrops, the change of refractive power was -0.1 ± 0.2 D (0 to -0.25) and the change of mean axial length was 0.15 ± 0.23 mm (0-1.05). The mean pupil diameter was 6.7 ± 0.6 mm (5.3-9.3) and the near accommodation point was 6.1 ± 2.0 cm (3.1-11.0). Two patients (3.1%) complained of near-work disturbance but none stopped taking the eyedrops. Conclusions Significant decreases in the changes of refractive power and axial length were evident in myopic elementary schoolchildren after low-dose atropine therapy. Low-dose atropine attenuates myopic progression without severe complications.

Purpose: We aimed to report the clinical and radiological outcomes of staged surgery using the acute induced membrane technique with an antibiotic-impregnated cement spacer (ACS) and soft-tissue reconstructive surgery and to identify factors affecting clinical outcomes. Materials and Methods: Thirty-two patients with severe open tibia fractures were treated via staged surgery from January 2014 to December 2019 and followed up for ≥1 year. In the first surgery, an ACS was inserted into the bone defect site along with debridement and irrigation and was temporarily fixed in place with an external fixator. The internal fixator was placed, and flap surgery and cement spacer changes were performed during the next surgery. In the third surgery, an autogenous bone graft was performed. Radiologic and functional results were investigated according to the Association for the Study and Application of the Method of Ilizarov (ASAMI) criteria, and factors affecting the ASAMI score were analyzed. Results: The average bone defect width was 43.9 mm, and the size of soft-tissue defect was 79.3 cm2 . Bone union was achieved in all cases except one and required 9.4 months on average. Complications occurred in 10 cases (31.2%). Good or better clinical effects, in terms of ASAMI radiologic and functional scores, were observed in 29 and 24 cases, respectively. Complications and additional surgery were common factors affecting the two scores. Conclusion Staged surgery using the acute induced membrane technique and soft-tissue reconstructive surgery is an efficacious treatment for open tibial fractures with bone defects.

Purpose: Next-generation sequencing (NGS) can facilitate precision medicine approaches in metastatic colorectal cancer (mCRC) patients. We investigated the molecular profiling of Korean mCRC patients under the K-MASTER project which was initiated in June 2017 as a nationwide precision medicine oncology clinical trial platform which used NGS assay to screen actionable mutations. Materials and Methods: As of 22 January 2020, total of 994 mCRC patients were registered in K-MASTER project. Targeted sequencing was performed using three platforms which were composed of the K-MASTER cancer panel v1.1 and the SNUH FIRST Cancer Panel v3.01. If tumor tissue was not available, cell-free DNA was extracted and the targeted sequencing was performed by Axen Cancer Panel as a liquid biopsy. Results: In 994 mCRC patients, we found 1,564 clinically meaningful pathogenic variants which mutated in 71 genes. Anti-EGFR therapy candidates were 467 patients (47.0%) and BRAF V600E mutation (n=47, 4.7%), deficient mismatch repair/microsatellite instability–high (n=15, 1.5%), HER2 amplifications (n=10, 1.0%) could be incorporated with recently approved drugs. The patients with high tumor mutation burden (n=101, 12.7%) and DNA damaging response and repair defect pathway alteration (n=42, 4.2%) could be enrolled clinical trials with immune checkpoint inhibitors. There were more colorectal cancer molecular alterations such as PIK3CA, KRAS G12C, atypical BRAF, and HER2 mutations and even rarer but actionable genes that approved or ongoing clinical trials in other solid tumors. Conclusion K-MASTER project provides an intriguing background to investigate new clinical trials with biomarkers and give therapeutic opportunity for mCRC patients.