Purpose: To compare near-distance reading speeds across different intraocular lens (IOL) types using a Korean reading speed measurement application. Methods: Patients who underwent bilateral cataract surgery and received trifocal IOL (Panoptix), extended depth of focus (EDoF) IOL (Vivity), or enhanced monofocal IOL (Eyhance) were enrolled. Korean reading speed and reading & speaking speed were measured using a Korean reading speed measurement application. Additionally, satisfaction with visual function in everyday life was assessed using a questionnaire. Results: No statistically significant differences were observed in postoperative corrected distance visual acuity among the three groups (p = 0.71). The Panoptix group demonstrated significantly higher distance-corrected near visual acuity than the other two groups (p < 0.05). For letter sizes of logMAR 0.5 or larger, the Panoptix group exhibited significantly higher reading and reading & speaking speeds than the other two groups. For letter sizes of logMAR 0.8 or larger, the Vivity group showed significantly higher reading and reading & speaking speeds than the Eyhance group (p < 0.05). The Panoptix group showed significantly greater satisfaction with visual function in work at near distances, including that for activities such as reading a book. Conclusion The Panoptix trifocal IOL is expected to provide superior near-vision function and patient satisfaction than other IOL types.

Purpose: To evaluate the long-term results of Boston type-I keratoprosthesis implantation in Korea. Methods: Medical records of six patients (six eyes) who underwent Boston type-I keratoprosthesis implantation between August 2018 and November 2019 were retrospectively reviewed for more than 36 months. Results: The mean follow-up period was 44.3 ± 7.0 months. Best corrected visual acuity (BCVA) improved significantly for all six eyes, from 2.33 ± 0.51 logarithm of the minimum angle of resolution (logMAR) to 0.67 ± 0.59 logMAR. The vision recovered immediately after the surgery in all patients. Retroprosthetic membrane developed in three of the patients, but the visual acuity remained unchanged. Anatomical success was achieved in all six eyes after Boston type-I keratoprosthesis implantation. Conclusions The long-term analysis of Boston type-I keratoprosthesis implantation showed a faster recovery and improved visual acuity compared with conventional penetrating keratoplasty. Without the use of systemic immunosuppressants, all six eyes showed long-term survival of the Boston keratoprosthesis. Boston type-I keratoprosthesis implantation may be used in patients with recurrent graft failure after keratoplasty. This was the first study investigating the long-term results of Boston keratoprosthesis implantation in Korean patients.

Purpose: To evaluate the reliability and validity of the Cataract-related Visual Function Questionnaire (CVFQ). Methods: A prospective cross-sectional study of 141 cataract patients was conducted from March 2022 to June 2022. The questionnaire was created based on a literature review and advice from an expert panel. This study determined its construct validity, criterion validity, internal consistency, and test-retest reliability. Results: The CVFQ consists of 15 items distributed among five categories: overall visual quality, overall visual function, distance vision, near vision, and glare. In the exploratory factor analysis of validity, the first three principal components explained 77.8% of the variance. The p-values in the Spearman correlation test comparing the pre- and postoperative total CVFQ score and best-corrected visual acuity (BCVA) were 0.006 and 0.004, respectively. In the reliability analysis, Cronbach’s alpha was > 0.9 for internal consistency and the p-values of each subcategory were all significant in the analysis of test-retest reliability. Conclusions Our results indicate that the CVFQ is useful for measuring the visual quality and visual function of cataract patients in Korea.

Nonalcoholic fatty liver disease (NAFLD) is a leading cause of liver disease worldwide. The estimated global incidence of NAFLD is 47 cases per 1,000 population and is higher among males than females. The estimated global prevalence of NAFLD among adults is 32% and is higher among males (40%) compared to females (26%). The global prevalence of NAFLD has increased over time, from 26% in studies from 2005 or earlier to 38% in studies from 2016 or beyond. The prevalence of NAFLD varies substantially by world region, contributed by differing rates of obesity, and genetic and socioeconomic factors. The prevalence of NAFLD exceeds 40% in the Americas and South-East Asia. The prevalence of NAFLD is projected to increase significantly in multiple world regions by 2030 if current trends are left unchecked. In this review, we discuss trends in the global incidence and prevalence of NAFLD and discuss future projections.

Gastric cancer is one of the most common cancers in Korea and the world. Since 2004, this is the 4th gastric cancer guideline published in Korea which is the revised version of previous evidence-based approach in 2018. Current guideline is a collaborative work of the interdisciplinary working group including experts in the field of gastric surgery, gastroenterology, endoscopy, medical oncology, abdominal radiology, pathology, nuclear medicine, radiation oncology and guideline development methodology. Total of 33 key questions were updated or proposed after a collaborative review by the working group and 40 statements were developed according to the systematic review using the MEDLINE, Embase, Cochrane Library and KoreaMed database. The level of evidence and the grading of recommendations were categorized according to the Grading of Recommendations, Assessment, Development and Evaluation proposition. Evidence level, benefit, harm, and clinical applicability was considered as the significant factors for recommendation. The working group reviewed recommendations and discussed for consensus. In the earlier part, general consideration discusses screening, diagnosis and staging of endoscopy, pathology, radiology, and nuclear medicine. Flowchart is depicted with statements which is supported by meta-analysis and references. Since clinical trial and systematic review was not suitable for postoperative oncologic and nutritional follow-up, working group agreed to conduct a nationwide survey investigating the clinical practice of all tertiary or general hospitals in Korea. The purpose of this survey was to provide baseline information on follow up. Herein we present a multidisciplinary-evidence based gastric cancer guideline.

Purpose: To study the long-term efficacy and safety of Flexivue Microlens refractive corneal inlays in Koreans for compensation of presbyopia. Methods: Flexivue Microlens inlays were implanted in nine eyes at Samsung Medical Center from October 2015 to February 2018. The follow-up period was 1.95 ± 0.6 years. Pre- and postoperative near/intermediate/distant visual acuity, spherical equivalent, contrast sensitivity, defocus curve, keratometry, and patient satisfaction were evaluated retrospectively. Results: The uncorrected near visual acuity (UNVA) of the operated eye increased significantly to 0.27 ± 0.10 logarithm of the minimal angle resolution (logMAR) after 6 months (p = 0.012). At the last observation, it was 0.32 ± 0.21 logMAR, which improved compared to before surgery, but the difference was not significant (p = 0.127). The binocular UNVA improved significantly to 0.19 ± 0.78 logMAR at 6 months postoperatively (p = 0.017) and to 0.21 ± 0.13 logMAR at the last observation (p = 0.028). There was no difference in the binocular uncorrected distant visual acuity (UDVA) before and after surgery, but the UDVA of the operated eye decreased significantly to 0.38 ± 0.15 logMAR at 6 months postoperatively (p = 0.007) and to 0.32 ± 0.21 logMAR at the last observation (p = 0.012). Satisfaction with near vision improved significantly after surgery; 14.3% of the patients had a score of 4 (good) or higher and 42.9% did not require near-vision glasses. In one case, the inlay was removed after 17 months due to blurred vision. Conclusions The Flexivue Microlens has a low risk of complications and is a reversible technique. However, the near vision improvement was temporary and distance vision deteriorated. In addition, the Koreans examined had relatively low satisfaction and high spectacle dependence.

Objective: To investigate the relationship between reduced glutathione (GSH), a key molecule of the antioxidant defense system in the blood, and glutathione reductase (GR), which reduces oxidized glutathione (glutathione disulfide [GSSG]) to GSH and maintains the redox balance, with the prevalence of Alzheimer’s dementia and cognitive decline. Methods: In all, 20 participants with Alzheimer’s dementia who completed the third follow-up clinical evaluation over 6 years were selected, and 20 participants with normal cognition were selected after age and sex matching. The GSH and GR concentrations were the independent variables. Clinical diagnosis and neurocognitive test scores were the dependent variables indicating cognitive status. Results: The higher the level of GR, the greater the possibility of having normal cognition than of developing Alzheimer’s dementia. Additionally, the higher the level of GR, the higher the neurocognitive test scores. However, this association was not significant for GSH. After 6 years, the conversion rate from normal cognition to cognitive impairment was significantly higher in the lower 50th percentile of the GR group than in the upper 50th percentile. Conclusion The higher the GR, the lower the prevalence of Alzheimer’s dementia and incidence of cognitive impairment and the higher the cognitive test scores. Therefore, GR is a potential protective biomarker against Alzheimer’s dementia and cognitive decline.

Purpose: To compare the efficacy and safety of conventional scleral fixation (C-SF), retropupillary iris-claw intraocular lens (RP-IOL) implantation, and intrascleral fixation (ISF). Methods: This retrospective observational study included 58 patients (58 eyes) who underwent C-SF (23 eyes), RP-IOL (23 eyes), and ISF (12 eyes) by a single surgeon at Samsung Medical Center from October 2017 to July 2020 and were followed up for at least 6 months. This study analyzed various clinical outcomes before surgery, and 1 day, 1 week, 1 month, 3 months, and 6 months after surgery. Results: Six months after surgery, best-corrected visual acuity in logarithm of minimum angle of resolution was 0.08 ± 0.10, 0.08 ± 0.16, and 0.03 ± 0.04 in C-SF group, RP-IOL group, and ISF group, respectively, and there was a significant improvement in each group compared to preoperative best-corrected visual acuity. All groups showed a significant increase in astigmatism postoperatively, but no between-group differences were observed. The prediction error was -0.15 ± 0.77, 0.56 ± 0.62, and 0.44 ± 1.00 diopters in the three groups, respectively, indicating RP-IOL group and ISF group for hyperopic shift. The three groups did not differ in terms of absolute prediction error. Six months after surgery, the corneal endothelial cell counts were 2,073 ± 691, 2,014 ± 692, and 1,712 ± 891 cells/mm2, respectively, which were lower than before surgery. IOL dislocation occurred in five eyes only in RP-IOL group, two of which underwent two reoperations, and reenclavation was performed smoothly without complications in all cases. Conclusions Although the frequency of IOL dislocation in RP-IOL group was higher than that in the other groups, it can be reenclavated relatively easily. As a method of secondary IOL fixation, both RP-IOL implantation and ISF were as effective as conventional scleral fixation.

Purpose: To derive the optimized intraocular lens (IOL) constants from automated and manifest refraction after cataract surgery in Korean patients, and to evaluate whether there is a difference in optimized IOL constants according to the refraction method. Methods: This retrospective multicenter cohort study enrolled 4,103 eyes of 4,103 patients who underwent phacoemulsification and in-the-bag IOL implantation at 18 institutes. Optimized IOL constants for the SRK/T, Holladay, Hoffer Q, and Haigis formulas were calculated via autorefraction or manifest refraction of samples using the same biometry and IOL. The IOL constants derived from autorefraction and manifest refraction were compared. Results: Of the 4,103 eyes, the majority (62.9%) were measured with an IOLMaster 500 followed by an IOLMaster 700 (15.2%). A total of 33 types of IOLs were used, and the Tecnis ZCB00 was the most frequently used (53.0%). There was no statistically significant difference in IOL constants derived from autorefraction and manifest refraction when IOL constants were optimized with a large number of study subjects. On the other hand, optimized IOL constants derived from autorefraction were significantly smaller than those from manifest refraction when the number of subjects was small. Conclusions It became possible to use the IOL constants optimized from Koreans to calculate the IOL power. However, if the IOL constant is optimized using autorefraction in a small sample group, the IOL constant tends to be small, which may lead to refractive error after surgery.