MACULAR MICROVASCULATURE IN X-LINKED RETINOSCHISIS: Optical Coherence Tomography and Optical Coherence Tomography Angiography Study.

PURPOSE: The study aimed to evaluate the macular microvasculature of X-linked retinoschisis (XLRS) and identify correlations between vascular changes, structural changes, and functional outcome. METHODS: Genetically confirmed XLRS patients and heathy control subjects underwent complete ophthalmic examination, dilated funduscopic examination, optical coherence tomography, and optical coherence tomography angiography. Schisis distribution, outer plexiform layer discontinuation, photoreceptor layer thickness, and photoreceptor outer segment length were reviewed using optical coherence tomography. Vascular flow density and foveal thickness at foveal and parafoveal area were measured using optical coherence tomography angiography. RESULTS: A total of 17 eyes of 9 XLRS patients and 22 eyes of 11 control subjects were examined from July 2018 to August 2020. Flow density in the deep capillary plexus at foveal and parafoveal area decreased in XLRS patients compared with control subjects (P = 0.014 and 0.001, respectively), whereas foveal avascular zone area and perimeter remarkably increased (P = 0.015 and 0.001, respectively). Although outer and total retinal layers were significantly thicker in XLRS, inner retinal layer was thinner with reduced photoreceptor layer thickness and shortened photoreceptor outer segment length (P < 0.001 and P < 0.001, respectively). Foveal flow loss in deep capillary plexus, foveal avascular zone enlargement, thinner inner retina and photoreceptor layer thickness, and shortened photoreceptor outer segment length correlated with best-corrected visual acuity. CONCLUSION: X-linked retinoschisis eyes exhibit decreased flow density in the deep capillary plexus and variable foveal avascular zone with enlarged perimeter. Structural deterioration of the photoreceptor best reflects the degenerative changes, whereas microvascular alteration shows considerable correlation with functional outcome in XLRS.

CENTRAL RETINAL VEIN OCCLUSION IN YOUNG PATIENTS: Clinical Characteristics and Prognostic Factors.

PURPOSE: To investigate the clinical characteristics and prognostic factors of young patients with central retinal vein occlusion (CRVO). METHODS: This retrospective cohort study involved treatment-naïve patients with CRVO. Medical records regarding basic demographics, predisposing factors, ocular characteristics, and treatments were reviewed and compared according to age at CRVO onset. RESULTS: We enrolled 263 patients, of whom 69 were younger patients. Younger patients had higher prevalence of nontraditional risk factors including physical or psychological stress (P = 0.032), hematologic abnormalities (P = 0.003), and better visual acuity at baseline and last visit (all P < 0.001) and were unlikely to undergo intravitreal injections (47.8 vs. 68.6%, P < 0.001) during follow-up. Younger patients had higher prevalence of paracentral acute middle maculopathy (28.1 vs. 4.7%, P < 0.001). Older age (odds ratio = 1.165, P = 0.028), male sex (odds ratio = 7.074, P = 0.034), coexisting renal disease (odds ratio = 7.845, P = 0.050), and poor baseline visual acuity (odds ratio = 16.069, P = 0.002) were significant risk factors for poor visual outcomes in young CRVO patients. CONCLUSION: Younger CRVO patients had a milder clinical course with fewer treatments and were more likely to have nontraditional risk factors than older patients.

Usefulness of the University of California San Diego Performance-Based Skills Assessment for the evaluation of cognitive function and activities of daily living function in patients with cognitive impairment.

OBJECTIVES: To assess the usefulness of the University of California San Diego Performance-Based Skills Assessment (UPSA) as a new diagnostic method and tool for the assessment of cognitive function and activities of daily living function in patients with cognitive impairment. METHOD: In total, 35 patients with cognitive impairment and 35 healthy controls were recruited for this study. The Mini-Mental State Examination (MMSE), Clinical Dementia Rating (CDR), and Global Deterioration Scale (GDS) were used for the evaluation of cognitive function, while the Barthel Activities of Daily Living Index (BADL), Instrumental Activities of Daily Living Index (IADL), and UPSA were used for the evaluation of activities of daily living function. RESULTS: UPSA scores were significantly lower in patients with cognitive impairment than in controls. The UPSA total score was significantly correlated with MMSE, CDR, GDS, and IADL scores. With regard to the detection of cognitive impairment, UPSA exhibited a greater determination power (R2 = 0.593) compared with BADL (R2 = 0.149) and IADL (R2 = 0.423) and higher sensitivity and specificity compared with IADL. CONCLUSION: Our results suggest that UPSA is a useful tool for the evaluation of cognitive function and activities of daily living function in patients with cognitive impairment.

A comparison of short-term postoperative outcomes including nutritional status between gastrectomy with simultaneous cholecystectomy and gastrectomy only in patients with gastric cancer.

OBJECTIVE: We aimed to evaluate the effect of simultaneous cholecystectomy on the short-term postoperative outcomes and nutritional status in patients with gastric cancer. METHODS: We retrospectively reviewed data from 4,820 patients with gastric cancer who underwent gastrectomy from January 2011 to December 2016. Patients who underwent only gastrectomy (N=4,578) were matched to those who underwent simultaneous cholecystectomy during gastrectomy (N=242) at a 1:1 ratio using propensity score matching analysis. The nutritional status and inflammatory responses preoperatively and postoperatively and postoperative outcomes were compared between the groups. RESULTS: The simultaneous cholecystectomy group showed more intraoperative blood loss and a longer operative time than the gastrectomy only group [150.0 (100.0, 200.0) mL vs. 100.0 (100.0, 200.0) mL, P=0.006; 176.0 (150.0, 210.0) min vs. 155.0 (128.0, 188.0) min, P<0.001, respectively]. Intraoperative event rate, postoperative complication rate, and postoperative recovery did not differ between the groups. All parameters including body weight, the hemoglobin level, absolute lymphocyte count, total protein level, albumin level, fasting glucose level, and prognostic nutritional index excluding the cholesterol level were not significantly different between the groups, and their changing patterns were similar. Although the cholesterol level was significantly lower in the simultaneous cholecystectomy group than in the gastrectomy only group at all follow-up points, the mean value of the decreased cholesterol level was within normal range. CONCLUSIONS: In gastric cancer patients with gallbladder disease, simultaneous cholecystectomy is safe and not associated with additional nutritional loss.

PREDICTORS OF REFRACTORY MACULAR EDEMA AFTER BRANCH RETINAL VEIN OCCLUSION FOLLOWING INTRAVITREAL BEVACIZUMAB.

PURPOSE: To evaluate the predictors of refractory macular edema (ME) that develops despite multiple bevacizumab injections in patients with branch retinal vein occlusion (BRVO). METHODS: A total of 107 patients who followed at least 2 years were assigned to 2 groups: a refractory group (n = 56) and a responsive group (n = 51). Baseline characteristics, treatment response at 3 months, and fluorescein angiographic findings at 6 months were compared. Then we tried to identify factors associated with refractory ME development. RESULTS: Compared to the responsive group, the refractory group had older age, longer pre-treatment duration, and shorter occlusion distance from disk. At 3 months, the refractory group exhibited lower visual acuity, thicker central retinal thickness (CRT), and larger proportion of external limiting membrane (ELM) and outer plexiform layer disruption. After 6 months, proportion of unresolved vein occlusion, macular ischemia, number of microaneurysms, and non-perfusion areas were higher in the refractory group. Refractory ME was associated with pre-treatment duration ≥3 months, short occlusion distance from disk, thick CRT and ELM disruption at 3 months, and unresolved vein occlusion at 6 months. CONCLUSION: If BRVO-ME patients exhibit the above-mentioned characteristics, they may have refractory ME, which should inform treatment decisions.

Surgical Outcomes After Open, Laparoscopic, and Robotic Gastrectomy for Gastric Cancer.

BACKGROUND: In contrast to the significant advantages of laparoscopic versus open gastrectomy, robotic gastrectomy has shown little benefit over laparoscopic gastrectomy. This study aimed to compare multi-dimensional aspects of surgical outcomes after open, laparoscopic, and robotic gastrectomy. METHODS: Data from 915 gastric cancer patients who underwent gastrectomy by one surgeon between March 2009 and May 2015 were retrospectively reviewed. Perioperative parameters were analyzed for short-term outcomes. Surgical success was defined as the absence of conversion to open surgery, major complications, readmission, positive resection margin, or fewer than 16 retrieved lymph nodes. RESULTS: This study investigated 241 patients undergoing open gastrectomy, 511 patients undergoing laparoscopic gastrectomy, and 173 patients undergoing robotic gastrectomy. For each approach, the respective incidences were as follows: conversion to open surgery (not applicable, 0.4%, and 0%; p = 0.444), in-hospital major complications (5.8, 2.7, and 1.2%; p = 0.020), delayed complications requiring readmission (2.9, 2.0, and 1.2%; p = 0.453), positive resection margin (1.7, 0, and 0%; p = 0.003), and inadequate number of retrieved lymph nodes (0.4, 4.1, and 1.7%; p = 0.010). Compared with open and laparoscopic surgery, robotic gastrectomy had the highest surgical success rate (90, 90.8, and 96.0%). Learning-curve analysis of success using cumulative sum plots showed success with the robotic approach from the start. Multivariate analyses identified age, sex, and gastrectomy extent as significant independent parameters affecting surgical success. Surgical approach was not a contributing factor. CONCLUSIONS: Open, laparoscopic, and robotic gastrectomy exhibited different incidences and causes of surgical failure. Robotic gastrectomy produced the best surgical outcomes, although the approach method itself was not an independent factor for success.

Comparison of perioperative surgical outcomes between a bipolar device and an ultrasonic device during laparoscopic gastrectomy for gastric cancer.

BACKGROUND: The use of energy devices during laparoscopic gastrectomy for gastric cancer has increased as the frequency of laparoscopic surgery has increased. Our aim was to compare the perioperative surgical outcomes between using a bipolar device and an ultrasonic device during laparoscopic gastrectomy. METHODS: Retrospective review of a prospectively maintained database identified 186 patients who underwent laparoscopic gastrectomy performed by a single surgeon between November 2010 and August 2013. A bipolar device was used for 116 patients, and an ultrasonic device was used for 70 patients. Patient characteristics and perioperative surgical outcomes were compared between groups. RESULTS: Clinicopathologic characteristics were similar for both groups. The bipolar group had a significantly shorter operation time (154.9 vs. 167.8 min, p = 0.028) and higher rate of D2 lymph node dissection (29.3 vs. 15.7 %, p = 0.012). The bipolar device group experienced significantly less pain at 12 h [visual analog scale (VAS) pain score: 3.9 vs. 4.7, p = 0.027) and 18 h (VAS pain score: 3.5 vs. 4.1, p = 0.036) postoperatively. The bipolar group had earlier abdominal drain removal (p = 0.001) and a shorter hospital stay (p = 0.024). No significant differences in laboratory value changes, morbidity, or mortality were observed between the groups. CONCLUSION: Compared with the ultrasonic device, the bipolar device provided advantages in operation time, degree of postoperative pain, time of drain removal, and length of hospital stay. The bipolar device may be a useful and efficient energy device for laparoscopic gastrectomy. However, larger studies to confirm the safety of bipolar device during laparoscopic gastrectomy are warranted.

Synergistic integration of ion-exchange and catalytic reduction for complete decomposition of perchlorate in waste water.

Ion-exchange has been frequently used for the treatment of perchlorate (ClO4(-)), but disposal or regeneration of the spent resins has been the major hurdle for field application. Here we demonstrate a synergistic integration of ion-exchange and catalytic decomposition by using Pd-supported ion-exchange resin as an adsorption/catalysis bifunctional material. The ion-exchange capability of the resin did not change after generation of the Pd clusters via mild ethanol reduction, and thus showed very high ion-exchange selectivity and capacity toward ClO4(-). After the resin was saturated with ClO4(-) in an adsorption mode, it was possible to fully decompose the adsorbed ClO4(-) into nontoxic Cl(-) by the catalytic function of the Pd catalysts under H2 atmosphere. It was demonstrated that prewetting the ion-exchange resin with ethanol significantly accelerate the decomposition of ClO4(-) due to the weaker association of ClO4(-) with the ion-exchange sites of the resin, which allows more facile access of ClO4(-) to the catalytically active Pd-resin interface. In the presence of ethanol, >90% of the adsorbed ClO4(-) could be decomposed within 24 h at 10 bar H2 and 373 K. The ClO4(-) adsorption-catalytic decomposition cycle could be repeated up to five times without loss of ClO4(-) adsorption capacity and selectivity.

Artificial Intelligence Model Assisting Thyroid Nodule Diagnosis and Management: A Multicenter Diagnostic Study.

CONTEXT: It is not clear how to integrate artificial intelligence (AI)-based models into diagnostic workflows. OBJECTIVE: To develop and validate a deep-learning-based AI model (AI-Thyroid) for thyroid cancer diagnosis, and to explore how this improves diagnostic performance. METHODS: The system was trained using 19 711 images of 6163 patients in a tertiary hospital (Ajou University Medical Center; AUMC). It was validated using 11 185 images of 4820 patients in 24 hospitals (test set 1) and 4490 images of 2367 patients in AUMC (test set 2). The clinical implications were determined by comparing the findings of six physicians with different levels of experience (group 1: 4 trainees, and group 2: 2 faculty radiologists) before and after AI-Thyroid assistance. RESULTS: The area under the receiver operating characteristic (AUROC) curve of AI-Thyroid was 0.939. The AUROC, sensitivity, and specificity were 0.922, 87.0%, and 81.5% for test set 1 and 0.938, 89.9%, and 81.6% for test set 2. The AUROCs of AI-Thyroid did not differ significantly according to the prevalence of malignancies (>15.0% vs ≤15.0%, P = .226). In the simulated scenario, AI-Thyroid assistance changed the AUROC, sensitivity, and specificity from 0.854 to 0.945, from 84.2% to 92.7%, and from 72.9% to 86.6% (all P < .001) in group 1, and from 0.914 to 0.939 (P = .022), from 78.6% to 85.5% (P = .053) and from 91.9% to 92.5% (P = .683) in group 2. The interobserver agreement improved from moderate to substantial in both groups. CONCLUSION: AI-Thyroid can improve diagnostic performance and interobserver agreement in thyroid cancer diagnosis, especially in less-experienced physicians.

The diagnostic performance and clinical value of deep learning-based nodule detection system concerning influence of location of pulmonary nodule.

BACKGROUND: The deep learning-based nodule detection (DLD) system improves nodule detection performance of observers on chest radiographs (CXRs). However, its performance in different pulmonary nodule (PN) locations remains unknown. METHODS: We divided the CXR intrathoracic region into non-danger zone (NDZ) and danger zone (DZ). The DZ included the lung apices, paramediastinal areas, and retrodiaphragmatic areas, where nodules could be missed. We used a dataset of 300 CXRs (100 normal and 200 abnormal images with 216 PNs [107 NDZ and 109 DZ nodules]). Eight observers (two thoracic radiologists [TRs], two non-thoracic radiologists [NTRs], and four radiology residents [RRs]) interpreted each radiograph with and without the DLD system. The metric of lesion localization fraction (LLF; the number of correctly localized lesions divided by the total number of true lesions) was used to evaluate the diagnostic performance according to the nodule location. RESULTS: The DLD system demonstrated a lower LLF for the detection of DZ nodules (64.2) than that of NDZ nodules (83.2, p = 0.008). For DZ nodule detection, the LLF of the DLD system (64.2) was lower than that of TRs (81.7, p < 0.001), which was comparable to that of NTRs (56.4, p = 0.531) and RRs (56.7, p = 0.459). Nonetheless, the LLF of RRs significantly improved from 56.7 to 65.6 using the DLD system (p = 0.021) for DZ nodule detection. CONCLUSION: The performance of the DLD system was lower in the detection of DZ nodules compared to that of NDZ nodules. Nonetheless, RR performance in detecting DZ nodules improved upon using the DLD system. CRITICAL RELEVANCE STATEMENT: Despite the deep learning-based nodule detection system's limitations in detecting danger zone nodules, it proves beneficial for less-experienced observers by providing valuable assistance in identifying these nodules, thereby advancing nodule detection in clinical practice. KEY POINTS: • The deep learning-based nodule detection (DLD) system can improve the diagnostic performance of observers in nodule detection. • The DLD system shows poor diagnostic performance in detecting danger zone nodules. • For less-experienced observers, the DLD system is helpful in detecting danger zone nodules.

Monthly Alternating Injections of Aflibercept and Bevacizumab for Neovascular Age-Related Macular Degeneration.

We investigated the efficacy of monthly alternating injections of aflibercept and bevacizumab (MAAB) for maintenance treatment in patients with neovascular age-related macular degeneration (AMD) who showed improvement with the initial monthly injections but presented with rapid worsening after conversion to bimonthly injections. We included 72 patients with neovascular AMD who showed improvement with loading injections of aflibercept. For maintenance treatment, bevacizumab was administered every alternate month between the bimonthly aflibercept injections in 24 (33.3%) eyes showing worsening (MAAB group). The other eyes were treated with aflibercept (BiA group) bimonthly. Baseline low retinal thickness, thick choroid, and presence of intraretinal fluid were associated with worsening after extending the injection intervals. Visual improvement was lower in the MAAB group than in the BiA group, but the final visual outcomes were comparable. Additional bevacizumab stabilized the early fluctuation of retinal thickness, thus maintaining long-term visual stability without increasing the risk of geographic atrophy or disciform scar until the second year. Previously treated eyes or those with polypoidal choroidal vasculopathy responded less to the initial loading doses and showed worsening under the bimonthly regimen. MAAB was effective in preventing anatomical and functional deterioration when bimonthly aflibercept proved insufficient for the maintenance treatment of neovascular AMD.

Usefulness of Silent MRA for Evaluation of Aneurysm after Stent-Assisted Coil Embolization.

OBJECTIVE: To determine the usefulness of Silent MR angiography (MRA) for evaluating intracranial aneurysms treated with stent-assisted coil embolization. MATERIALS AND METHODS: Ninety-nine patients (101 aneurysms) treated with stent-assisted coil embolization (Neuroform atlas, 71 cases; Enterprise, 17; LVIS Jr, 9; and Solitaire AB, 4 cases) underwent time-of-flight (TOF) MRA and Silent MRA in the same session using a 3T MRI system within 24 hours of embolization. Two radiologists independently interpreted both MRA images retrospectively and rated the image quality using a 5-point Likert scale. The image quality and diagnostic accuracy of the two modalities in the detection of aneurysm occlusion were further compared based on the stent design and the site of aneurysm. RESULTS: The average image quality scores of the Silent MRA and TOF MRA were 4.38 ± 0.83 and 2.78 ± 1.04, respectively (p < 0.001), with an almost perfect interobserver agreement. Silent MRA had a significantly higher image quality score than TOF MRA at the distal internal carotid artery (n = 57, 4.25 ± 0.91 vs. 3.05 ± 1.16, p < 0.001), middle cerebral artery (n = 21, 4.57 ± 0.75 vs. 2.19 ± 0.68, p < 0.001), anterior cerebral artery (n = 13, 4.54 ± 0.66 vs. 2.46 ± 0.66, p < 0.001), and posterior circulation artery (n = 10, 4.50 ± 0.71 vs. 2.90 ± 0.74, p = 0.013). Silent MRA had superior image quality score to TOF MRA in the stented arteries when using Neuroform atlas (4.66 ± 0.53 vs. 3.21 ± 0.84, p < 0.001), Enterprise (3.29 ± 1.59 vs. 1.59 ± 0.51, p = 0.003), LVIS Jr (4.33 ± 1.89 vs. 1.89 ± 0.78, p = 0.033), and Solitaire AB stents (4.00 ± 2.25 vs. 2.25 ± 0.96, p = 0.356). The interpretation of the status of aneurysm occlusion exhibited significantly higher sensitivity with Silent MRA than with TOF MRA when using the Neuroform Atlas stent (96.4% vs. 14.3%, respectively, p < 0.001) and LVIS Jr stent (100% vs. 20%, respectively, p = 0.046). CONCLUSION: Silent MRA can be useful to evaluate aneurysms treated with stent-assisted coil embolization, regardless of the aneurysm location and type of stent used.

Synthesizing realistic high-resolution retina image by style-based generative adversarial network and its utilization.

Realistic image synthesis based on deep learning is an invaluable technique for developing high-performance computer aided diagnosis systems while protecting patient privacy. However, training a generative adversarial network (GAN) for image synthesis remains challenging because of the large amounts of data required for training various kinds of image features. This study aims to synthesize retinal images indistinguishable from real images and evaluate the efficacy of the synthesized images having a specific disease for augmenting class imbalanced datasets. The synthesized images were validated via image Turing tests, qualitative analysis by retinal specialists, and quantitative analyses on amounts and signal-to-noise ratios of vessels. The efficacy of synthesized images was verified by deep learning-based classification performance. Turing test shows that accuracy, sensitivity, and specificity of 54.0 ± 12.3%, 71.1 ± 18.8%, and 36.9 ± 25.5%, respectively. Here, sensitivity represents correctness to find real images among real datasets. Vessel amounts and average SNR comparisons show 0.43% and 1.5% difference between real and synthesized images. The classification performance after augmenting synthesized images outperforms every ratio of imbalanced real datasets. Our study shows the realistic retina images were successfully generated with insignificant differences between the real and synthesized images and shows great potential for practical applications.

Technical feasibility and efficacy of a standard needle magnetization system for ultrasound needle guidance in thyroid nodule-targeting punctures: a phantom study.

PURPOSE: The aim of this study was to assess the feasibility and efficacy of an ultrasound needle guidance system (NGS) based on standard needle magnetization in a phantom study of thyroid nodule (TN)-targeting punctures. METHODS: Six trainees and a staff radiologist performed TN-targeting punctures with or without the NGS in phantom models (group 1, experience <50 cases; group 2, experience ≥50 cases and <100 cases; group 3, experience ≥100 cases of TN-targeting punctures). The feasibility, technical success rate, number of punctures, and procedure time were recorded. RESULTS: The feasibility of NGS was 98.6% (138/140). In group 1, the technical success rate increased from 60.0%±8.2% to 80.0%±8.2% when the NGS was used (P=0.046), with a reduction in the number of punctures from 2.2 to 1.2 (P=0.005). In group 2, the rate changed from 95.0%±5.8% to 100.0%±0.0% with the NGS (P=0.157), with a minimal decrease in the number of punctures from 1.1 to 1.0 (P=0.157). The procedure time significantly decreased in both groups (P=0.041 and P=0.010, respectively) when the NGS was used. In group 3, there were no significant differences in the technical success rate and the number of punctures according to whether the NGS was used (P=0.317 and P=0.317, respectively). CONCLUSION: NGS using standard needle magnetization is technically feasible and has potential to improve the efficacy of TN-targeting punctures for less-experienced operators, especially beginners, according to the findings of this phantom study.

Genetic Profile and Associated Characteristics of 150 Korean Patients with Retinitis Pigmentosa.

PURPOSE: Retinitis pigmentosa (RP) shows great diversity between genotypes and phenotypes, and it is important to identify the causative genes. This study aimed to analyze the molecular profiles, associated ocular characteristics, and progression of RP in Korean patients. METHODS: All the genetic variants in patients with RP, identified using targeted next-generation sequencing (NGS) with a panel of 88 RP-related genes between November 2018 and November 2019, were retrospectively reviewed. All the patients underwent comprehensive ophthalmological evaluations, and their clinical and family histories were recorded. The best-corrected visual acuity (BCVA) deterioration and photoreceptor disruption progression rates were determined based on the major causative mutational genes using nonlinear mixed models, and the differences among them were investigated using the interaction effect. RESULTS: Among the 144 probands, 82 variants in 24 causative genes were identified in 77 families (53.5%). Most of the RP cases were associated with autosomal recessive variants (N = 64 (44.4%)), followed by autosomal dominant (N = 10 (6.9%)) and X-linked variants (N = 3 (2.1%)). The four most frequently affected genes were EYS (N = 15 (10.4%)), USH2A (N = 12 (8.3%)), PDE6B (N = 9 (6.3%)), and RP1 (N = 8 (5.6%)). Epiretinal membranes and cystoid macular edema were frequently noted in the patients with USH2A (75.0%) and PDE6B (50.0%) variants, respectively. During the follow-up period, the BCVA and photoreceptor disruption changes were significantly different among the patients carrying the four common causative genes (P=0.014 and 0.034, resp.). Patients with PDE6B variants showed faster BCVA changes (0.2 LogMAR/10 years), and those with USH2A variants showed the fastest ellipsoid zone disruptions (-170.4 µm/year). CONCLUSION: In conclusion, our genetic analysis using targeted NGS provides information about the prevalence of RP-associated mutations in Korean patients. Delineating clinical characteristics according to genetic variations may help clinicians identify subtype features and predict the clinical course of RP.

Glaucoma as a prognostic factor of central retinal vein occlusion: visual and anatomical outcomes and occurrence of ischaemic central retinal vein occlusion.

PURPOSE: To compare the functional and anatomical outcomes of central retinal vein occlusion (CRVO) according to the presence of glaucoma before the onset of CRVO, and to assess whether pre-existing glaucoma affects the prognosis of CRVO in terms of development and conversion to ischaemic CRVO. METHODS: In this retrospective cohort study, patients with treatment-naïve CRVO were enrolled between December 2009 and February 2019. The patients were classified into two groups according to the presence of pre-existing primary open-angle glaucoma at CRVO diagnosis. We reviewed medical records regarding basic demographics, ocular characteristics and treatments. The effects of pre-existing glaucoma on the occurrence of ischaemic CRVO were also investigated using Cox proportional hazard models. RESULTS: Of 166 eyes from 166 patients, 26 (15.7%) had pre-existing glaucoma. The pre-existing glaucoma group revealed significantly older (69.4 ± 13.3 versus 56.5 ± 15.9) and lower BCVA at baseline (1.06 ± 0.75 versus 0.64 ± 0.58, logMAR) and final visits (1.56 ± 1.35 versus 0.64 ± 0.48, logMAR) (all p < 0.05) than non-glaucomatous group. In terms of perfusion status of CRVO, the glaucoma group showed higher incidence of ischaemic CRVO (30.8% versus 5.3%, p = 0.052) at initial and last visits as well as more disorganization of retinal inner layers (DRIL) at 3 months (76.0% versus 49.6%, p = 0.015). Pre-existing glaucoma (hazard ratio (HR) = 2.141, p = 0.014), lower vision at baseline (HR = 2.071, p = 0.001) and DRIL at 3 months (HR = 2.905, p = 0.011) were significant risk factors for the occurrence of ischaemic CRVO. CONCLUSION: In patients with CRVO, pre-existing glaucoma was associated with poorer visual and anatomical outcomes, and played as a significant risk factor for the development and conversion to ischaemic CRVO with lower vision and presence of DRIL at early phase of CRVO.

Diverse Genetic Landscape of Suspected Retinitis Pigmentosa in a Large Korean Cohort.

We conducted targeted next-generation sequencing (TGS) and/or whole exome sequencing (WES) to assess the genetic profiles of clinically suspected retinitis pigmentosa (RP) in the Korean population. A cohort of 279 unrelated Korean patients with clinically diagnosed RP and available family members underwent molecular analyses using TGS consisting of 88 RP-causing genes and/or WES with clinical variant interpretation. The combined genetic tests (TGS and/or WES) found a mutation in the 44 RP-causing genes and seven inherited retinal disease (IRD)-causing genes, and the total mutation detection rate was 57%. The mutation detection rate was higher in patients who experienced visual deterioration at a younger age (75.4%, age of symptom onset under 10 years) and who had a family history of RP (70.7%). The most common causative genes were EYS (8.2%), USH2A (6.8%), and PDE6B (4.7%), but mutations were dispersed among the 51 RP/IRD genes generally. Meanwhile, the PDE6B mutation was the most common in patients experiencing initial symptoms in their first decade, EYS in their second to third decades, and USH2A in their fifth decades and older. Of note, WES revealed some unexpected genotypes: ABCC6, CHM, CYP4V2, RS1, TGFBI, VPS13B, and WDR19, which were verified by ophthalmological re-phenotyping.

A novel energy efficient path for nitrogen fixation using a non-thermal arc.

Plasma-assisted nitrogen fixation is a promising sustainable and clean alternative to the classical Haber-Bosch process. However, the high energy consumption and low production rate of plasma-assisted nitrogen fixation limit its application. This study shows that the non-thermal (non-equilibrium) enhancement of the arc plasma significantly reduces the energy consumption of nitrogen fixation. The highest energy efficiency with high NO selectivity is observed with a low specific energy input (SEI). However, the highest production rate is reached at a high SEI. The studied process offers high NO selectivity (up to 95%) with low energy consumption (∼48 GJ per tN) at 0.1 kJ L-1 SEI, which is much lower than the previously reported value of plasma-assisted atmospheric nitrogen fixation and is close to that of the Haber-Bosch process.

Trends of robotic-assisted surgery for thyroid, colorectal, stomach and hepatopancreaticobiliary cancer: 10 year Korea trend investigation.

BACKGROUND: The current position of robotic surgery in the field of minimally invasive surgery remains ambiguous. We evaluated long-term trends of robotic general surgery and the future direction of its development. METHODS: Data on robotic cancer surgeries between 2005 and 2014 were retrospectively collected by volunteer institutions in the Republic of Korea. Spearman's correlation and logistic regression analyses were used to compare robotic and laparoscopic surgery trends in general surgery. RESULTS: The odds that robotic surgery was performed instead of laparoscopic surgery significantly decreased in the fields of colorectal, stomach, and hepato-biliary-pancreatic surgery (odds ratio [OR]: 0.95, 95% confidence interval [CI]: 0.93-0.97; OR: 0.90, 95% CI: 0.88-0.92; and OR: 0.71, 95% CI: 0.65-0.78, respectively), except for thyroid surgery (OR: 1.28, 95% CI: 1.25-1.30). Of the total numbers of each procedure, proportions of robotic intersphincteric resections, abdominoperineal resections, and pylorus-preserving surgery performed significantly increased (r = 0.98, P < .001; r = 0.78, P = .01; and r = 0.86, P = .007, respectively). CONCLUSIONS: The use of robotic surgery failed to preponderate that of laparoscopic surgery, except for thyroid surgery. Robotic surgery is increasingly preferred for limited fields or complex surgeries, but the use of robotics in simple surgeries has decreased.

Measurement of Stomach Wall Thickness to Guide Staple Selection during Sleeve Gastrectomy.

BACKGROUND: Sleeve gastrectomy has been considered a primary bariatric surgery; however, surgeons concerned with staple line leakage often query whether staples selected during stomach resection are of an appropriate size. This study aimed to measure gastric wall thickness using pathology laboratory measurements and to identify variables correlated with stomach wall thickness in patients who had undergone laparoscopic sleeve gastrectomy. METHODS: We obtained fresh resected stomach wall specimens from 30 patients. Stomach wall thickness was immediately measured postoperatively, comprising the muscle layer of the antrum, body, and fundus. Results were correlated with body mass index (BMI), age, and sex and with diagnoses of presurgical diabetes, hypertension, hyperlipidemia, and fatty liver. RESULTS: Stomach wall thickness ranged from 3.4 ± 4.3 mm to 1.0 ± 9.6 mm at the antrum. Except for the whole layer at the body wall, there was no significant correlation between wall thickness and other factors. At the body wall, whole layer wall thickness was found to positively correlate with age, sex, diabetes, and smoking (r = 0.469, - 0.391, 0.396, and 0.349, respectively; p < 0.05 in all patients). CONCLUSION: Stomach wall thickness varied among patients who had undergone laparoscopic sleeve gastrectomy according to samples taken at three stomach wall sites. The range in wall thickness was normal, and thus, surgeons need not hesitate in selecting the staple height. Also, our study may be helpful to guide surgeon choice concerning the third or fourth staple around the body area when considering a patient's independent factors.