Direct measurements of the colloidal Debye force

Colloids often behave in a manner similar to their counterparts in molecular space and are used as model systems to understand molecular behavior. Here, we study like-charged colloidal attractions between a permanent dipole on an interfacial particle and its induced dipole on a water-immersed particle caused by diffuse layer polarization. We find that the scaling behavior of the measured dipole-induced dipole (D‒I) interaction via optical laser tweezers is in good agreement with that predicted from the molecular Debye interaction. The dipole character propagates to form aggregate chains. Using coarse-grained molecular dynamic simulations, we identify the separate roles of the D‒I attraction and the van der Waals attraction on aggregate formation. The D‒I attraction should be universal in a broad range of soft matter, such as colloids, polymers, clays, and biological materials, motivating researchers to further conduct in-depth research on these materials.

Nasal and temporal curvatures of lamina CRIBROSA in myopic eyes

Little is known about the myopic characteristics of lamina cribrosa (LC) curvature. As such, we investigated nasal and temporal LC curvatures in myopia. In this retrospective, cross-sectional study, 144 myopic eyes (refraction < − 2D) and 88 non-myopic eyes (refraction > − 0.5D) underwent swept-source optical coherence tomography scanning of the LC. The anterior border of LC curvature was delineated with 17 points and interpolated with the “cardinal spline” curve-fitting method. The average curvature indices of the temporal and nasal sides were presented as the temporal and nasal curvatures. Myopic eyes had a mean refraction of − 6.7 ± 2.8D, while for non-myopic eyes, the value was 0.3 ± 1.0D. Nasal LC curvature was visible in 54 myopia (37.5%) and 42 non-myopia (47.7%) cases (P = 0.126), and temporal LC curvature was visible in 142 myopia (98.6%) and 68 non-myopia (77.3%) cases (P = 0.001). The nasal LC curvature was significantly larger in myopia than in non-myopia (P < 0.001). Contrastingly, the temporal LC curvature was significantly smaller in myopia than in non-myopia (P < 0.001). Axial length was associated with larger nasal LC curvature, smaller temporal LC curvature, and larger nasal–temporal LC curvature difference (all P’s < 0.05). In myopic relative to non-myopic eyes, LC curvature was decreased temporally and increased nasally.

Impact of Glaucoma Severity on Rates of Neuroretinal Rim, Retinal Nerve Fiber Layer, and Macular Ganglion Cell Layer Thickness Change

PURPOSE

To determine the impact of glaucoma severity on rates of change of minimum rim width (MRW), peripapillary retinal nerve fiber layer (RNFL), and macular ganglion cell layer (GCL) thickness.

DESIGN

Prospective, cohort study.

METHODS

Glaucoma patients and healthy subjects had optical coherence tomography scans at 6-month intervals. Individual rates of change for MRW, RNFL, and GCL thickness were estimated with ordinary least-squares regression. Linear mixed-effect models were used to estimate the rate of change of each parameter and evaluate the impact of glaucoma severity (expressed by visual field mean deviation, MD) and age on these rates.

RESULTS

A total of 132 glaucoma patients and 57 healthy subjects were followed for a median of 4.3 years and 3.7 years, respectively. Healthy subjects had a statistically significant deterioration in MRW (-1.66 µm/year), RNFL (-0.46 µm/year), and GCL thickness (-0.22 µm/year). While glaucoma patients had a faster rate of change in each parameter compared with healthy subjects, only GCL thickness showed a statistically significant group difference (mean difference: -0.17 µm/year; P = .03). Older baseline age was associated with faster GCL thickness change (-0.07 µm/year; P = .03), but not other parameters. Baseline MD had no impact on the subsequent rates of change in any of the parameters.

CONCLUSIONS

The rates of MRW, RNFL, and GCL thickness change were not significantly influenced by glaucoma severity at baseline; however, GCL thickness was able to statistically contrast the rate of change between healthy subjects and glaucoma patients throughout the disease spectrum.

Effects of Beta-zone Peripapillary Atrophy and Focal Lamina Cribrosa Defects on Peripapillary Vessel Parameters in Young Myopic Eyes

PRECIS

The development of beta-zone peripapillary atrophy (β-PPA) and focal lamina cribrosa defect (FLD) was significantly associated with decreased peripapillary optical coherence tomography angiography (OCTA) vessel parameters in young myopic eyes.

PURPOSE

The purpose of this study was to investigate whether β-PPA and FLD affect peripapillary vessel density (VD) or perfusion density (PD) from OCTA in young myopic eyes.

MATERIALS AND METHODS

In a cross-sectional study, 330 eyes of 165 healthy volunteers with myopia were involved. Eyes underwent OCTA to measure peripapillary PD and VD. Eyes were grouped according to the presence of β-PPA or FLD: eyes without β-PPA or FLD (group A), eyes with β-PPA but without FLD (group B), and eyes with both β-PPA and FLD (group C). PD and VD were compared among 3 groups, and linear mixed-effect regression model was used to investigate the determinants of PD.

RESULTS

β-PPA was found in 219 eyes (66.4%), and FLD was detected in 27 eyes (8.2%). The average VD and PD were greatest in group A (19.13±2.04 mm-1 and 0.375±0.038), followed by group B (18.34±2.26 mm-1 and 0.363±0.042) and group C (16.71±2.81 mm-1 and 0.330±0.052) (P<0.001). The linear mixed-effect model demonstrated that presence of FLD (P=0.001) or β-PPA (P<0.001), FLD count (P=0.004), and maximal β-PPA width (P<0.001) were significantly associated with average PD after controlling for multiple confounding factors.

CONCLUSIONS

Development of β-PPA and FLD, which is closely related with axial elongation in myopic eyes, was significantly associated with reduced OCTA vessel parameters in young myopic eyes. OCTA may help to detect vascular changes and assess glaucoma risk in these eyes.

Association of Intereye Visual-Sensitivity Asymmetry With Progression of Primary Open-Angle Glaucoma

Purpose

To investigate the relationship between intereye visual field defect (VFD) asymmetry and subsequent VF progression in primary open-angle glaucoma (POAG).

Methods

Moderate-stage patients with POAG (226 eyes of 113 patients) with a single hemifield defect were followed for 8.7 years. Participants were categorized into three groups by initial VF pattern: (1) unilateral VFD, (2) bilateral VFD within same hemifield (superior–superior, inferior–inferior), (3) bilateral VFD within opposite hemifield (superior–inferior). The mean deviation (MD) difference between the intereye was defined as the intereye MD asymmetry index (iMAI). Intereye visual-sensitivity difference within the same hemifield was calculated as the intereye hemifield visual-sensitivity asymmetry index. Functional progression was detected by Glaucoma Progression Analysis. The overall rate of MD change and the association between new indices were evaluated by linear regression. A Kaplan-Meier survival analysis was performed and the factors associated with glaucoma progression were evaluated by Cox proportional hazard modeling.

Results

Unilateral VFD eyes and bilateral VFD eyes within opposite VF hemifield showed significant progression and faster rate of MD change compared with bilateral VFD eyes within same VF hemifield (71.1% vs. 45.9% vs. 21.1% [P = 0.001]; –1.27 dB/y vs. −0.64 dB/y vs. −0.32 dB/y [P = 0.001]). Unilateral VFD eyes showed the fastest time to VF progression compared with other groups (P = 0.002). A faster rate of MD change was associated with greater intereye MD asymmetry index (P = 0.001) and greater intereye hemifield visual-sensitivity asymmetric index (P = 0.031), which were significant risk factors for glaucoma progression (all P < 0.001).

Conclusions

Among POAG eyes with comparable hemifield VFDs, eyes without a corresponding hemifield defect in the fellow eye showed faster rates of progression compared with those with a corresponding hemifield defect.

Safety Climate and Productivity Improvement of Construction Workplaces Through 6S System: Mixed-Method Analysis of 5S and Safety Integration

The purpose of this study is to develop a framework for integrating essential safety practices (visualization, job safety analysis, and plan-do-check-act) into 5S steps and validate it. First, 18 interviews with a snowball sample of construction workers, safety representatives, supervisors, site and project managers were conducted. A grounded theory method was utilized to code the interview data. The results revealed that studied construction companies implement a systematic safety-based methodology to minimize construction work injuries. Second, to validate the proposed framework, a pre- and post-test study was applied. The case and control groups (26 participants) answered a 6S questionnaire before the 6S system and one month after it. The results revealed that safety climate and productivity significantly increased for the case group but reduced for the control group during time.

Ten-year-and-beyond longitudinal change of ß-zone parapapillary atrophy in glaucoma: association with retinal nerve fibre layer defect

BACKGROUND

To investigate the longitudinal change of localised retinal nerve fibre layer (RNFL) defects associated with change of ß-zone parapapillary atrophy (PPA) in primary open-angle glaucoma (POAG) eyes.

METHODS

POAG patients with a localised RNFL defect and ß-zone PPA who had undergone disc/RNFL photography at 1-year intervals for 10 years or longer were enrolled. The topographic parameters of ß-zone PPA (area, maximal radial extent and angular extent around disc) were measured. Progression of RNFL defect was defined as widening of defect and/or appearance of new defect. The factors associated with progression of RNFL defect were assessed by OR using multivariable logistic regression.

RESULTS

A total of 209 patients (209 eyes) with POAG were included (mean: 54 years old). Over the course of 11.5±2.3-year follow-up period, progression of RNFL defect was detected in 114 eyes (54.5%). Enlargement of PPA parameters (area and angular extent) was significantly more common in patients with RNFL defect progression than in eyes without progression (all p<0.001, respectively). Widening of radial extent did not show a significant difference in both groups (p=0.61). Increment of angular extent was in the direction of RNFL defect progression in 82.1% of eyes. Progression of RNFL defect was significantly associated with disc haemorrhage (OR: 6.653, p<0.001), enlargement of PPA area (OR: 4.114, p=0.004) and angular extent (OR: 6.572, p<0.001).

CONCLUSIONS

Progression of RNFL defect is associated with increment of angular extent of PPA in POAG eyes.

Longitudinal Observation of Border Tissue Configuration During Axial Elongation in Childhood

Purpose

To investigate the change of border tissue configuration during axial elongation in childhood.

Methods

Fifty-four subjects (108 eyes; age range, 29.3–132.5 months) who had undergone a series of swept-source optical coherence tomography scans at intervals of 6 months or longer were classified into stable axial length (AXL) eyes (n = 55; AXL change of ≤0.36 mm) and elongating AXL eyes (n = 53; AXL change of >0.36 mm). The angle between the Bruch's membrane opening (BMO) reference plane and the border tissue of Elschnig was defined as the border tissue angle (BTA). The border tissue angle, BMO distance (BMOD) and minimum rim width (MRW) were measured in the temporal and nasal regions.

Results

During 15.6 ± 7.2 months of follow-up, the AXL significantly increased from 22.8 ± 1.3 mm to 23.3 ± 1.4 mm (P < 0.001). Changes of border tissue angle and AXL showed a significant correlation only in the temporal region of elongating AXL eyes (r = –0.409; P = 0.002), but not in stable AXL eyes. Both BMOD and nasal MRW significantly increased from 1482.5 ± 153.0 to 1506.1 ± 154.6 µm and from 310.6 ± 83.2 to 324.6 ± 95.6 µm, respectively (all Ps < 0.001). The changes of BMOD and nasal MRW showed a significant positive correlation with changes of AXL in elongating AXL eyes but not in stable AXL eyes.

Conclusions

During the axial elongation in childhood, temporal border tissue configuration change, BMO enlargement, and nasal peripapillary tissue elevation showed a significant correlation with changes in the AXL.

New hole transport styrene polymers bearing highly π-extended conjugated side-chain moieties for high-performance solution-processable thermally activated delayed fluorescence OLEDs

New polystyrene-based polymers with high π-extended hole transport pendants were synthesized to obtain a low turn-on voltage and high efficiency in solution-processed green TADF-OLEDs.

Phase Angle and Frailty Are Important Prognostic Factors in Critically Ill Medical Patients: A Prospective Cohort Study

OBJECTIVES

To investigate whether phase angle (PhA) measured by bioelectrical impedance analysis (BIA) and frailty are associated with the outcomes of critical illnesses.

DESIGN

A single-center prospective cohort study.

SETTING

Medical intensive care unit (ICU) in Seoul National University Hospital, Seoul, Republic of Korea.

PARTICIPANTS

97 patients who were admitted to the medical ICU.

MEASUREMENTS

On admission, PhA was measured by BIA, and frailty was assessed by the Korean Modified Barthel Index (KMBI) scoring system. Patients were classified according to PhA and KMBI scores, and their impact on the outcomes of critical illnesses was evaluated.

RESULTS

The patients' mean age was 62.4 ± 16.4 years, and 56 of the patients (57.7%) were men. Having a high PhA above 3.5 at the time of ICU admission was associated with lower in-hospital mortality (adjusted OR 0.42, p = .042), and a shorter duration of ICU stay (5.6 days vs. 9.8 days, p = .016) compared to those with a low PhA. Other indices measured by BIA were not significantly associated with outcomes of critical illnesses. Frailty (KMBI > 60) was associated with more mechanical ventilation days (2.3 days vs. 7.1 days; p = .018).

CONCLUSION

Both PhA and frailty are important prognostic factors predicting the outcomes of critical illnesses. Low PhA scores were associated with increased mortality and a longer duration of ICU stay, and frailty was associated with more mechanical ventilation days.

Novel carbazole-acridine-based hole transport polymer for low turn-on voltage of green quantum dot light-emitting diodes

We synthesized a novel hole transporting polymer (P-CzAc) for solution-processable green QD-LEDs. Compared to PVK, the P-CzAz-based device showed higher device performance.

Estimating visual field loss from monoscopic optic disc photography using deep learning model

Visual field assessment is recognized as the important criterion of glaucomatous damage judgement; however, it can show large test–retest variability. We developed a deep learning (DL) algorithm that quantitatively predicts mean deviation (MD) of standard automated perimetry (SAP) from monoscopic optic disc photographs (ODPs). A total of 1200 image pairs (ODPs and SAP results) for 563 eyes of 327 participants were enrolled. A DL model was built by combining a pre-trained DL network and subsequently trained fully connected layers. The correlation coefficient and mean absolute error (MAE) between the predicted and measured MDs were calculated. The area under the receiver operating characteristic curve (AUC) was calculated to evaluate the detection ability for glaucomatous visual field (VF) loss. The data were split into training/validation (1000 images) and testing (200 images) sets to evaluate the performance of the algorithm. The predicted MD showed a strong correlation and good agreement with the actual MD (correlation coefficient = 0.755; R2 = 57.0%; MAE = 1.94 dB). The model also accurately predicted the presence of glaucomatous VF loss (AUC 0.953). The DL algorithm showed great feasibility for prediction of MD and detection of glaucomatous functional loss from ODPs.

Association between esodeviation and primary open-angle glaucoma: the 2010-2011 Korea National Health and Nutrition Examination Survey

BACKGROUND/AIMS

To evaluate the association between strabismus and primary open-angle glaucoma (POAG) in a representative Korean population.

METHODS

A total of 11 114 participants aged 20 years or older in the Korea National Health and Nutrition Examination Survey database for the years 2010 through 2011 were reviewed. A standardised protocol was used to interview every participant and to perform comprehensive ophthalmic examinations. Glaucoma diagnosis was based on fundus photography and frequency-doubling technology perimetry results, according to the International Society of Geographical and Epidemiological Ophthalmology criteria. Ocular alignment was evaluated using the alternate prism and cover test, and clinically significant horizontal strabismus was defined as exodeviation of ≥15 prism dioptres (PD) and esodeviation of ≥10 PD. Univariate and multivariate regression analyses were used to evaluate the potential risk factors for POAG.

RESULTS

In the Korean population, subjects with clinically significant esodeviation had a much higher prevalence of POAG (12.32%) than those without clinically significant esodeviation (3.14%, p=0.016). After adjusting for age and intraocular pressure, clinically significant esodeviation was independently associated with POAG (OR 7.61, p=0.002).

CONCLUSION

Esodeviation was independently associated with POAG in the Korean population. This could be the result of, at least in part, ocular-adduction-induced greater strain on the temporal optic nerve head and peripapillary tissues, which makes eyes with esodeviation more vulnerable to POAG.

Diagnostic Accuracy of Wide-Field Map from Swept-Source Optical Coherence Tomography for Primary Open-Angle Glaucoma in Myopic Eyes

PURPOSE

To compare the accuracy of glaucomatous defects and diagnostic power for primary open-angle glaucoma (POAG) between swept-source optical coherence tomography (SS-OCT) and spectral-domain OCT (SD-OCT) in myopic eyes.

DESIGN

Prospective, case-control study.

METHODS

A total of 150 myopic POAG eyes and 100 healthy myopic eyes underwent SD-OCT and SS-OCT in random order on the same day. The locations of glaucomatous defects on SD-OCT thickness and deviation maps and SS-OCT wide-field thickness (thickness surfaces) and SuperPixel maps were rated, and the maps' accuracies were compared. The area under receiver operating characteristic (AUROC) of the peripapillary retinal nerve fiber layer (RNFL) and the macular parameters (GCL++: equivalent to ganglion cell-inner plexiform layer [GCIPL] + RNFL; GCL+: equivalent to GCIPL) from each of the devices for myopic POAG were calculated and compared.

RESULTS

The wide-field RNFL thickness (thickness surface) map showed the best accuracy for glaucomatous defects in the inferotemporal (96.4%) and superotemporal (92.4%) regions. The RNFL/GCL++/GCL+ wide-field thickness (thickness surface) map showed better accuracy for glaucomatous defects in both the superotemporal and inferotemporal regions than with the SD-OCT thickness map (all P values <.05). The average GCL++ (87.6%) and GCL+ (87.5%) thicknesses showed significantly greater AUROC for myopic POAG than GCIPL thickness from SD-OCT (83.8%, all P values <.05).

CONCLUSIONS

In myopic eyes, the SS-OCT wide-field map exhibited better accuracy for glaucomatous defect and greater diagnostic power for POAG than SD-OCT outcomes. This result might have been due to SS-OCT's wider scan and measurement area.

Genetic analysis of primary open-angle glaucoma-related risk alleles in a Korean population: the GLAU-GENDISK study

AIM

To validate six previously known primary open-angle glaucoma (POAG)-related loci in a Korean population.

METHODS

Representative POAG-related single-nucleotide polymorphisms (SNPs) from six loci (cyclin-dependent kinase 4 inhibitor B antisense RNA 1 (CDKN2B)-AS1, sineoculis homeobox homolog 1/sineoculis homeobox homolog 6(SIX1/SIX6), atonal BHLH transcription factor 7 (ATOH7), cell division cycle 7-transforming growth factor beta receptor 3, CAV1, transmembrane and coiled-coil domain family 1 (TMCO1) were selected and genotyped from discovery (POAG=309, heathy=5400) and replication cohorts (POAG=310, healthy=5612 and POAG=221, healthy=6244, respectively). Data were analysed using logistic regression to calculate the OR for POAG risk associated with SNP.

RESULTS

From the discovery cohort, rs1900004 in ATOH7 (OR=1.29, p=0.0024); rs1063192 (OR=0.69, p=0.0006), rs2157719 (OR=0.63, p=0.0007) and rs7865618 (OR=0.63, p=0.0006) in CDKN2B-AS1, and rs10483727 in SIX1/SIX6 (OR=0.68, p=7.9E-05) were nominally associated with the risk of POAG. The replication cohorts revealed nominal associations with rs2157719 (OR=0.72, p=0.0135), rs1063192 (OR=0.63, p=0.0007) and rs7865618 (OR=0.52, p=0.0004) in CDKN2B-AS1. A mega-analysis from the entire Korean population revealed significance with rs1063192 (OR=0.77, p=6.0E-05), rs2157719 (OR=0.63, p=0.0007) and rs7865618 (OR=0.58, p=1.9E-06) in CDKN2B-AS1 and with rs10483727 in SIX1/SIX6 (OR=0.79, p=9.4E-05), with the same direction of effect between the discovery association and the replication sample.

CONCLUSIONS

Variants near CDKN2B-AS1 and SIX1/SIX6 may require further investigation to obtain more genetic information on POAG development in a Korean population.

Interdigitation Zone Change According to Glaucoma-Stage Advancement

Purpose

To compare the macular interdigitation zone (IZ) of normal eyes with eyes showing different normal-tension glaucoma (NTG) stages.

Methods

Forty-two normal eyes (age, 56 ± 5.4 years), 45 pre-perimetric eyes (age, 59 ± 6.9 years), 51 mild-to-moderate glaucoma eyes (age, 58 ± 7.2 years; mean deviation [MD], –5.5 ± 3.0 dB), and 50 severe glaucoma eyes (age, 59 ± 6.9 years; MD, –15.1 ± 5.4 dB) were enrolled. All of the subjects underwent high-resolution spectral-domain optical coherence tomography (SD-OCT) to obtain 19 horizontal and 19 vertical macular B-scans 9 mm in length. The en face image of the scan area was divided into 589 rectangular boxes (side length of 375 µm). The IZ locations were marked on the corresponding image boxes. The IZ area was then quantified according to the number of boxes showing IZs among the 589 total boxes.

Results

The IZ area in the severe glaucoma eyes was significantly smaller than in the mild-to-moderate glaucoma eyes (28.99 ± 7.88 mm² vs. 40.79 ± 7.46 mm²; P < 0.001), was smaller in the mild-to-moderate glaucoma eyes than in the pre-perimetric glaucoma eyes (40.79 ± 7.46 mm² vs. 49.92 ± 8.10 mm²; P < 0.001), and was smaller still in the pre-perimetric glaucoma eyes than in the normal eyes (49.92 ± 8.10 mm² vs. 56.85 ± 7.94 mm²; P < 0.001). In the 146 NTG eyes, a statistically significant correlation was found between IZ area and MD (r = 0.64; P < 0.001).

Conclusions

SD-OCT revealed a reduction in IZ area in NTG eyes, and the extent of the reduction was positively associated with glaucoma severity. These findings suggest, though tentatively, that changes in the outer retinal layer can occur in the course of glaucoma progression.

Pre-perimetric Open Angle Glaucoma with Young Age of Onset: Natural Clinical Course and Risk Factors for Progression

PURPOSE

To investigate the natural clinical course of more than 5 years and the risk factors of progression in patients with pre-perimetric open angle glaucoma (OAG) of "young age of onset (under age 40)" without treatment.

DESIGN

Retrospective observational case series.

METHODS

Optic disc photography, red-free retinal nerve fiber layer (RNFL) photography, optical coherence tomography, and visual field (VF) examinations were performed every 6 months. Glaucoma progression was defined as structural or functional deterioration. A linear mixed-effects model was used to estimate the rate of structural and functional changes. Kaplan-Meier survival analysis and log-rank testing were used to compare survival experiences, and Cox proportional hazards modeling was performed to identify risk factors for glaucoma progression.

RESULTS

Of the 98 eyes of 98 patients (mean age, 30.6 years old), glaucoma progression was detected in 42 eyes (42.9%). The rate of average RNFL thickness thinning was -0.46 ± 0.50 μm/y, and the mean deviation (MD) change was -0.03 ± 0.13 dB/y. The glaucoma progression probability at 5 years was 39% by structural criteria and 5% by functional criteria. Older age at diagnosis (P = .004), presence of temporal raphe sign (horizontal straight line on macular ganglion cell-inner plexiform layer thickness map) (P = .011), lamina pore visibility (P = .034), and greater pattern standard deviation (P = .005) were significant factors for glaucoma progression.

CONCLUSIONS

In untreated pre-perimetric OAG patients with a "young age of onset" condition, the estimated MD slope for the disease course of more than 5 years was -0.03 dB/y, and the average RNFL thinning rate was -0.46 μm/y. The predictors for progression were structural parameters of temporal raphe sign, lamina pore visibility, and functional parameter of pattern standard deviation.

Peripapillary vessel parameters and mean ocular perfusion pressure in young healthy eyes: OCT angiography study

BACKGROUND

To investigate the relationship between estimated mean ocular perfusion pressure (MOPP) and peripapillary perfusion density (PD) or vessel density (VD) as measured by spectral-domain optical coherence tomography angiography (OCTA) in young healthy eyes.

METHODS

132 healthy participants (264 eyes) under 45 years of age underwent optic disc OCTA scan sized 3×3 mm to acquire PD and VD in the superficial vascular complex (SVC). Optic nerve head (ONH) parameters including retinal nerve fibre layer (RNFL) thickness, rim area and disc area were measured. MOPP was estimated from systemic blood pressure and intraocular pressure (IOP). A linear mixed model was used to find the systemic and ocular factors associated with PD and VD.

RESULTS

The average age of the subjects was 25.8±6.5 years. PD and VD showed a significant correlation with RNFL thickness (r=0.224, p<0.001 and r=0.214, p<0.001, respectively), but with MOPP, the correlation was only marginally significant (r=0.105, p=0.09 and r=0.112, p=0.07, respectively). After controlling for confounding factors, including age, sex, IOP, central corneal thickness, axial length and OCTA signal strength, PD and VD were significantly associated with ONH parameters (all p<0.05) but not with estimated MOPP (all p>0.05).

CONCLUSION

PD and VD in the SVC were significantly associated with ONH parameters while showing no association with estimated MOPP. OCTA-derived VD may not represent perfusion pressure, but is rather more dependent on peripapillary structure.

Impact of myopia on the association of long-term intraocular pressure fluctuation with the rate of progression in normal-tension glaucoma

BACKGROUND/AIMS

To investigate whether the association of long-term intraocular pressure (IOP) fluctuation with the rate of progression of normal-tension glaucoma (NTG) differs between myopia and non-myopia.

METHODS

The medical records of 65 myopic NTG (axial length (AL) > 24.0 mm) and 64 non-myopic NTG eyes (AL < 24.0 mm), who had been treated with topical medications for more than 5 years, were reviewed. Multiple linear regression models were fitted to analyse the relationships of the slope of mean deviation (MD) or visual field index (VFI) with the clinical factors, including the interactions with myopia.

RESULTS

The average follow-up period was 8.3 years. Twenty-two (22) non-myopic eyes (34.4%) and 27 myopic eyes (41.5%) showed NTG progression (p=0.511). The interaction of myopia with IOP fluctuation was a significant factor regarding both MD and VFI slope (p=0.002, 0.024, respectively); stratified analyses suggested that the risk effect of IOP fluctuation was significant only in myopic NTG in terms of both MD (β= -1.27, p=0.003) and VFI slope (β=-2.32, p=0.011).

CONCLUSION

Long-term IOP fluctuation was significantly related to faster visual field progression in myopic NTG eyes, compared with non-myopic NTG eyes.

Deep optic nerve head morphology and glaucoma progression in eyes with and without laminar dot sign: a longitudinal comparative study

PURPOSE

To investigate the association between the laminar dot sign (LDS) and the deep optic nerve head (ONH) structure in eyes with primary-open-angle glaucoma (POAG).

METHODS

Eighty-four eyes of 84 patients with POAG were prospectively included. All of the patients underwent stereo optic disc photography (SDP), red-free retinal nerve fibre layer (RNFL) photography, SS-OCT, and standard automated perimetry. By evaluating the SDP, patients were classified into laminar dot sign (LDS) and non-LDS groups. The deep structure of the ONH including the anterior prelaminar depth (APLD) and prelaminar tissue thickness (PTT) were quantitated using SS-OCT. Progression was assessed by structural or functional deterioration during the average 4.3 ± 1.2 years of follow-up.

RESULTS

The LDS group had deeper APLD (405.47 ± 107.55 vs. 302.45 ± 149.51, P < 0.001) and thinner PTT (74.34 ± 24.46 vs. 137.29 ± 40.07, P = 0.001) relative to the non-LDS group. By multivariate analysis, thin PTT was significantly associated with the presence of LDS (odds ratio = 0.939, P < 0.001). Structural progression was detected in 45 eyes (84.9%) in the LDS group and 8 eyes (25.8%) in the non-LDS group. Functional progression was demonstrated in 29 eyes (34.5%) in the LDS group and 6 eyes (19.4%) in the non-LDS group. The eyes with LDS had a significantly higher risk of glaucoma progression (χ² = 5.00, degree of freedom = 1, P = 0.033).

CONCLUSIONS

In eyes with POAG, the presence of LDS was associated with thinner prelaminar tissue and faster disease progression.

Twenty-four-Hour Intraocular Pressure-Related Patterns from Contact Lens Sensors in Normal-Tension Glaucoma and Healthy Eyes: The Exploring Nyctohemeral Intraocular pressure related pattern for Glaucoma Management (ENIGMA) Study

PURPOSE

To investigate 24-hour nyctohemeral intraocular pressure (IOP)-related patterns with contact lens sensors (CLSs) in eyes with primary open-angle glaucoma (POAG) with normal baseline IOP (i.e., normal-tension glaucoma [NTG]) and healthy controls.

DESIGN

Prospective, case-control study.

PARTICIPANTS

Thirty eyes of 30 patients with NTG, who had had a wash-out period for their IOP-lowering treatment, and 20 eyes of 20 healthy volunteer subjects.

METHODS

Patients and subjects were hospitalized for the purposes of 24-hour CLS (SENSIMED Triggerfish; Sensimed AG, Lausanne, Switzerland) measurement. The IOP-related patterns during wake and sleep times over the course of the 24 hours were compared between the 2 groups. The 24-hour ambulatory blood pressure and posture were monitored simultaneously. A generalized linear model was used to find the factors associated with NTG.

MAIN OUTCOME MEASURES

The IOP-related patterns, including mean and standard deviation (SD) of measurements, amplitude of cosine-fit curve, acrophase (signal peak), and bathyphase (signal trough) values (millivolt equivalents [mVEq]).

RESULTS

The SDs of the 24-hour CLS measurements were significantly greater in NTG eyes than in healthy controls (112.51±26.90 vs. 85.18±29.61 mVEq, P = 0.002). The amplitudes of cosine-fit curve (141.88±39.96 vs. 106.08±41.49 mVEq, P = 0.004) and acrophase values (277.74±129.80 vs. 190.58±127.88 mVEq, P = 0.024), mostly measured during nocturnal period, were significantly greater in NTG eyes than in healthy controls. The NTG subjects slept longer in the lateral decubitus posture than the healthy controls (199.1±137.8 vs. 113.2±86.2 minutes, P = 0.009). In the multivariable generalized linear model, the greater amplitude of cosine-fit curve (β = 0.218, P = 0.012) and greater time of decubitus posture during sleep (β = 0.180, P = 0.004) were found to be significantly associated with NTG.

CONCLUSIONS

Continuous monitoring of 24-hour IOP-related values with CLS can be useful for assessment of glaucoma risk, especially for patients with NTG whose IOP appears to be in the normal range. Fluctuation of 24-hour IOP-related values and posture during sleep time might be associated with NTG.

Morphological characteristics of parapapillary atrophy and subsequent visual field progression in primary open-angle glaucoma

BACKGROUND/AIMS

To investigate the associations between the morphological characteristics of beta-zone parapapillary atrophy (β-zone PPA) and subsequent visual field (VF) progression in eyes with primary open-angle glaucoma (POAG).

METHODS

One hundred and twenty-one POAG eyes with β-zone PPA along with 48 normal eyes with β-zone PPA were included. β-zone PPA area was calculated based on the PPA pixel area/optic-disc pixel area ratio and the optical coherence tomography (OCT)-measured disc area. β-zone PPA margin irregularity was quantified as a function of both area (A) and perimeter (P, calculated as 1/(4πA/P²)). VF progression was defined using standard automated perimetry's guided progression analysis software.

RESULTS

Of the 121 POAG eyes, 49 (40.5%) showed VF progression during the 10.1±1.9 years of follow-up. The baseline β-zone PPA area was similar among the three groups (Progressors, Non-progressors and Controls, p=0.995). However, the β-zone PPA irregularity index was significantly higher in the Progressors (p<0.001). The cumulative probability of VF progression was greater in the higher PPA irregularity index group (p<0.001, log-rank test). A Cox proportional hazards model showed the significant influences of optic disc haemorrhage (HR: 2.661, p=0.034) and higher baseline PPA irregularity index (HR: 1.455, p=0.007) on subsequent progression.

CONCLUSIONS

In POAG eyes, baseline β-zone PPA margin regularity was significantly associated with subsequent VF progression. Irregular margin of β-zone PPA might be the mark of vulnerability in the parapapillary area to further glaucomatous damage.

Clinical features and prognosis of patients with idiopathic pulmonary fibrosis and chronic obstructive pulmonary disease

<sec> <title>BACKGROUND</title> Idiopathic pulmonary fibrosis (IPF) and chronic obstructive pulmonary disease (COPD) share common risk factors. They could therefore be expressed in a single patient. However, the prevalence, clinical characteristics and prognosis of individuals with comorbid IPF and COPD are not known. </sec> <sec> <title>METHOD</title> From 2003 to 2007, the Korean Interstitial Lung Disease Study Group created a register for idiopathic interstitial pneumonia using 2002 ATS/ERS (American Thoracic Society/European Respiratory Society) criteria. Of the 1546 IPF patients assessed, 143 had decreased lung function consistent with COPD (IPF-COPD). COPD was diagnosed based on age (≥40 years) and pulmonary function (forced expiratory volume in 1 sec [FEV₁]/forced vital capacity [FVC] ratio < 0.7). </sec> <sec> <title>RESULTS</title> The median age of the IPF-COPD group was 71.0 years (interquartile range 66.0-76.0); most patients were male (88.1%). FVC (%) was significantly higher in the IPF-COPD group; however, FEV₁ (%) was significantly lower in the IPF-COPD group (P < 0.001). Diffusing capacity of the lung for carbon monoxide (DL_CO) was not significantly different between the two groups. In survival analysis, age and FVC (%), but not COPD, were significantly associated with prognosis (respectively P = 0.003, 0.001 and 0.401). COPD severity was also not related to prognosis (P = 0.935). </sec> <sec> <title>CONCLUSION</title> The prevalence of IPF-COPD was estimated to be ∼9.2% among all IPF patients; prognosis of patients with IPF-COPD was not worse than those with IPF alone. </sec>.

Macular Ganglion Cell-Inner Plexiform Layer Thickness Prediction from Red-free Fundus Photography using Hybrid Deep Learning Model

We developed a hybrid deep learning model (HDLM) algorithm that quantitatively predicts macular ganglion cell-inner plexiform layer (mGCIPL) thickness from red-free retinal nerve fiber layer photographs (RNFLPs). A total of 789 pairs of RNFLPs and spectral domain-optical coherence tomography (SD-OCT) scans for 431 eyes of 259 participants (183 eyes of 114 healthy controls, 68 eyes of 46 glaucoma suspects, and 180 eyes of 99 glaucoma patients) were enrolled. An HDLM was built by combining a pre-trained deep learning network and support vector machine. The correlation coefficient and mean absolute error (MAE) between the predicted and measured mGCIPL thicknesses were calculated. The measured (OCT-based) and predicted (HDLM-based) average mGCIPL thicknesses were 73.96 ± 8.81 µm and 73.92 ± 7.36 µm, respectively (P = 0.844). The predicted mGCIPL thickness showed a strong correlation and good agreement with the measured mGCIPL thickness (Correlation coefficient r = 0.739; P < 0.001; MAE = 4.76 µm). Even when the peripapillary area (diameter: 1.5 disc diameters) was masked, the correlation (r = 0.713; P < 0.001) and agreement (MAE = 4.87 µm) were not changed significantly (P = 0.378 and 0.724, respectively). The trained HDLM algorithm showed a great capability for mGCIPL thickness prediction from RNFLPs.

Ten Years and Beyond Longitudinal Change of ß-Zone Parapapillary Atrophy: Comparison of Primary Open-Angle Glaucoma with Normal Eyes

PURPOSE

To investigate the difference in longitudinal change of ß-zone parapapillary atrophy (PPA) between eyes with primary open-angle glaucoma (POAG) and normal eyes.

DESIGN

Longitudinal, observation study.

PARTICIPANTS

A total of 153 eyes with POAG and 105 normal eyes.

METHODS

Participants were followed for 10 years or more, with disc photography performed every year. The topographic parameters of ß-zone PPA (area, maximal radial extent, angular extent around disc) were measured. The factors associated with the enlargement of ß-zone PPA parameters were assessed by odds ratio (OR) using multivariable logistic regression.

MAIN OUTCOME MEASURES

Enlargement of ß-zone PPA parameters and associated factors.

RESULTS

Over the course of the average 11.6±1.3-year follow-up period, enlargement of β-zone PPA was detected in 66.7% of POAG eyes and in 26.7% of normal eyes. Increment of all PPA parameters was significantly more common in cases of POAG than in normal eyes (all P < 0.001). The spatial distribution of maximal radial extent at baseline and final examination was significantly different between the 2 groups: POAG eyes; inferotemporal versus normal eyes; temporal (chi-square = 26.549, P < 0.001, chi-square = 19.320, P = 0.004, respectively). The widening of radial extent was significantly associated with older age (OR, 1.036; P = 0.010) and the presence of glaucoma (OR, 2.599; P = 0.002). The increment of angular extent was associated with the presence of glaucoma (OR, 12.167; P = 0.017) and optic disc hemorrhage (OR, 3.266; P = 0.019).

CONCLUSIONS

The pattern of ß-zone PPA change differed between POAG and normal eyes during a follow-up of 10 years or more. The enlargement of PPA occurred more frequently in POAG than in normal eyes. The widening of radial extent was associated with older age and glaucoma, whereas the increment of angular extent was associated with glaucomatous damage.

Exploring the Novel Susceptibility Gene Variants for Primary Open-Angle Glaucoma in East Asian Cohorts: The GLAU-GENDISK Study

Primary open-angle glaucoma (POAG) can develop even within normal ranges of intraocular pressure, and this type of glaucoma (so-called ‘normal-tension glaucoma [NTG]’) is highly prevalent in East Asia including Korea and Japan. We conducted exome chip analysis to identify low-frequency and rare variants associated with POAG from the primary cohort (309 POAG patients and 5,400 control, all Koreans). For replication, Korean (310 POAG patients and 5,612 controls) and Japanese (565 POAG patients and 1,104 controls) cohorts were further investigated by targeted genotyping. SNP rs116121322 in LRRC27 showed nominally significant association with POAG in the discovery cohort (OR = 29.85, P = 2E–06). This SNP was validated in the Korean replication cohort but only in the NTG subgroups (OR = 9.86, P = 0.007). Japanese replication cohort did not show significant association with POAG (P .00.44). However, the meta-analysis in the entire cohort revealed significant association of rs116121322 with POAG (OR_combined = 10.28, P_combined = 1.4E–07). The LRRC27 protein expression was confirmed from human trabecular meshwork cells. For gene-based testing, METTL20 showed a significant association in POAG (P_combined = 0.002) and in the subgroup of NTG (P_combined = 0.02), whereas ZNF677 were significantly associated with only in the subgroup of high-tension glaucoma (P_combined = 1.5E–06). Our findings may provide further genetic backgrounds into the pathogenesis of POAG, especially for the patients who have lower baseline intraocular pressures.

Multidrug-resistant tuberculosis over 20 years at a referral hospital in South Korea: trends and outcomes

SETTING

A referral centre in South Korea.

OBJECTIVE

To investigate trends in drug resistance, treatment modalities and outcomes, and adverse events of multidrug-resistant tuberculosis (MDR-TB) over two decades.

DESIGN

MDR-TB patients treated at Seoul National Hospital University between 1996 and 2015 were divided into four 5-year cohorts according to the date of initial diagnosis. Changes in demographic characteristics, drug resistance, drugs used, treatment outcomes and adverse events over time were elucidated.

RESULTS

Between 1996 and 2015, 418 patients were treated for MDR-TB: 86 patients between 1996 and 2000, 125 between 2001 and 2005, 123 between 2006 and 2010, and 84 between 2011 and 2015. The proportion of patients with positive acid-fast bacilli sputum (60.5-29.7%, P < 0.001) or cavities on chest radiographs (86.0-40.5%, P < 0.001) decreased over time. Resistance to pyrazinamide, fluoroquinolones, cycloserine and p-aminosalicylic acid decreased. Later-generation fluoroquinolones (77.9-90.5%) and linezolid (0-26.2%) became more frequently prescribed. The treatment success rate increased (45.3-88.1%, P < 0.001); neurological adverse events, including peripheral neuropathy also increased (4.7-13.1%, P = 0.027).

CONCLUSION

MDR-TB patients presented with less severe disease and better resistance profiles over time in South Korea, with treatment outcomes improving continuously.

Machine learning classifiers-based prediction of normal-tension glaucoma progression in young myopic patients

PURPOSE

To assess the performance of machine learning classifiers for prediction of progression of normal-tension glaucoma (NTG) in young myopic patients.

STUDY DESIGN

Cross-sectional study.

METHODS

One hundred and fifty-five eyes of 155 myopic NTG patients (axial length [AL] ≥ 24.00 mm and refractive error ≤ - 3.0 D) between the ages of 20 and 40 were enrolled and divided into training (110) and test (45) sets. Sixty-five eyes showed glaucoma progression as defined by standard automated perimetry, while 91 eyes (nonprogressors) had been stable over the course of a follow-up period of at least 3 years. Two machine learning classifiers were built using the random forest and extremely randomized trees (extra-trees) models. Baseline clinical measurements obtained only at the initial visit were used as input features. The area under the receiver operating characteristic curve (AUC) was calculated to evaluate the accuracy of prediction.

RESULTS

Mean age and AL did not significantly differ between the 2 groups on either the training or the test set. The extra-trees model achieved an AUC of 0.881 [95% CI 0.814-0.945], higher than that of the random forest model (0.811 [0.731-0.888]; P = 0.010). The extra-trees model also outperformed all the clinical measurements for prediction of NTG progression, including average macular ganglion cell-inner plexiform layer thickness (0.735 [0.639-0.831]) and average circumpapillary retinal nerve fiber layer thickness (0.691 [0.590-0.792]; both P < 0.001).

CONCLUSIONS

In young myopic patients, the machine learning classifier with the extra-trees model can predict glaucomatous progression more effectively than clinical diagnostic parameters.

Diagnostic value of bronchoalveolar lavage and bronchial washing in sputum-scarce or smear-negative cases with suspected pulmonary tuberculosis: a randomized study

OBJECTIVES

Bronchoalveolar lavage (BAL) and bronchial washing (BW) are two major methods used to obtain high-quality respiratory specimens from patients with suspected pulmonary tuberculosis (TB) but a sputum-scarce or smear-negative status. We aimed to compare the value of BAL and BW in the diagnosis of TB in such patients.

METHODS

We enrolled patients with suspected pulmonary TB but with a sputum-scarce or smear-negative status who were referred for bronchoscopy between October 2013 and January 2016. Participants were randomized into the BAL and BW groups for evaluation. The primary outcome was the diagnostic yield for TB detection. Secondary outcomes included culture positivity, positivity of nucleic acid amplification tests (NAATs) for Mycobacterium tuberculosis and procedure-related complications.

RESULTS

A total of 94 patients were assessed and 91 (43 in the BAL group, 48 in the BW group) were analysed. Twenty-one patients (48.8%) in the BAL group and 30 (62.5%) in the BW group had a final diagnosis of pulmonary TB. The detection rate of M. tuberculosis by culture or NAAT was significantly higher in BAL specimens than in BW specimens (85.7% vs 50.0%, p 0.009). The procedure-related complications were hypoxic events, 2/43 (4.7%) in the BAL group and 5/48 (10.4%) in the BW group; and post-bronchoscopic fever, 3/43 (7.0%) in the BAL group and 4/48 (8.3%) in the BW group.

DISCUSSION

As long as it is tolerable, BAL rather than BW, should be used to obtain specimens for the diagnosis of pulmonary TB in sputum-scarce or smear-negative cases.

Signal Strength as an Important Factor in the Analysis of Peripapillary Microvascular Density Using Optical Coherence Tomography Angiography

The quality of the scan image is important in peripapillary circulation analysis using optical coherence tomography angiography (OCTA). We aimed to investigate the effects of signal strength (SS) on the peripapillary microvascular density acquired from OCTA. A total of 259 eyes from 259 young healthy subjects were included. Peripapillary OCTA images using 3 × 3 mm angiography scan were acquired from all participants. Subjects were divided into four groups according to the SS: SS 7, SS 8, SS 9, and SS 10. Vessel density (VD) and perfusion density (PD) of the superficial capillary plexus were calculated. VD and PD were compared among the four groups, and linear regression analyses were performed to identify and evaluate the clinical factors associated with average VD. As the SS increased from 7 to 10, the average VD and PD increased; these increases were statistically significant (all, p < 0.001). Regression analyses showed that four factors were significantly correlated with average VD: age (partial r = 0.133), average retinal nerve fiber layer thickness (partial r = 0.169), cup/disc ratio (partial r =-0.481), and SS (partial r = 0.413). SS is a significant factor affecting peripapillary microvascular density, and its influence is similar to well-known structural parameters associated with glaucoma.

Comparison of image quality of abdominopelvic CT in paediatric patients: low osmolar contrast media versus less iodine-containing iso-osmolar contrast media at different peak kilovoltages

AIM

To evaluate the effect of iso-osmolar contrast media (IOCM) at different tube voltages on image quality for abdominal computed tomography (CT) in paediatric patients.

MATERIALS AND METHODS

The low osmolar contrast media (LOCM) group and IOCM group consisted of 101 and 102 CT examinations, respectively, in patients <18 years old. Images were reviewed retrospectively. Objective measurement of the contrast enhancement and noise were analysed and contrast-to-noise ratios (CNRs) of the abdominal aorta, portal vein, and liver were calculated. Four radiologists participated in subjective analysis using a four-point scale system to evaluate degrees of contrast enhancement, image noise, beam-hardening artefact, and overall image quality. Reader performance for correctly differentiating the two kinds of contrast media was evaluated.

RESULTS

Regarding the objective measurement, contrast enhancement was significantly higher in the LOCM group (p<0.05). In subjective analysis, only CT using 120 kVp showed significantly stronger enhancement in the LOCM group (p=0.002), and sensitivity to differentiate the IOCM was 80.6%. Overall sensitivity and specificity for correctly differentiating IOCM were 57.1%, and 56.9%, respectively.

CONCLUSION

The application of IOCM was found to be feasible for performing paediatric abdominopelvic CT with a low tube voltage protocol. Although objective measurements of contrast enhancement were significantly lower in the IOCM group, subjective contrast enhancement and image quality assessments were not statistically different between groups.

Rate of three-dimensional neuroretinal rim thinning in glaucomatous eyes with optic disc haemorrhage

Background

To investigate the thinning rate of three-dimensional neuroretinal rim thickness (3D-NRT) in glaucoma eyes with optic disc haemorrhage (DH) and its relationship to retinal nerve fibre layer thickness (RNFLT) progression.

Methods

Ninety-five (95) eyes of 95 glaucoma patients with initial DH in the inferotemporal (n=69) and superotemporal (n=26) regions and 48 eyes of 48 glaucoma patients without DH were retrospectively reviewed. The rates of change for 3D-NRT and RNFLT were compared by linear mixed-effect model. For the direct comparison between 3D-NRT and RNFLT, dynamic-range-based normalised coefficient was used. The effect of DH frequency on the rates of thinning of 3D-NRT and RNFLT was evaluated.

Results

During a mean 7-year follow-up, the rates of thinning of 3D-NRT (–5.69±4.88 µm/year) and RNFLT (–2.03±2.03 µm/year) at 7 o’clock were faster than those at other locations (all p<0.05) in DH eyes. The dynamic-range-based normalised rate of thinning was significantly faster for RNFLT (–2.06%±1.62%/year) than for 3D-NRT (–1.15%±1.10%/year, p<0.001) in DH eyes, but not in non-DH eyes (p=0.43). DH frequency in the inferotemporal region was associated with the thinning rate of 3D-NRT as well as RNFLT.

Conclusion

DH eyes are associated with the progression of both 3D-NRT and RNFLT, especially in the inferotemporal region. DH eyes show a relatively faster thinning rate of average RNFLT than 3D-NRT. The frequency of DH can affect the progression of 3D-NRT as well as RNFLT.

Association of preoperative anemia and perioperative allogenic red blood cell transfusion with oncologic outcomes in patients with nonmetastatic colorectal cancer

Background

We investigated whether preoperative anemia and perioperative blood transfusion (pbt) are associated with overall survival and recurrence-free survival in patients with nonmetastatic colorectal cancer.

Methods

From 1 January 2009 to 31 December 2014, 1003 patients with primary colorectal cancer were enrolled in the study. Perioperative clinical and oncologic outcomes were analyzed based on the presence of preoperative anemia and pbt.

Results

Preoperative anemia was found in 468 patients (46.7%). In the anemia and no-anemia groups, pbt was performed in 44% and 15% of patients respectively. Independent predictors for pbt were preoperative anemia, higher American Society of Anesthesiologists score, laparotomy, lengthy operative time, advanced TNM stage, T4 stage, and 30-day morbidity. The use of pbt, but not preoperative anemia, was found to be an independent adverse prognostic factor for overall survival. In terms of recurrence-free survival, the presence of preoperative anemia was similarly not a significant prognostic factor, but the use of pbt was an independent factor for an unfavourable prognosis.

Conclusions

The use of pbt, but not preoperative anemia, was independently associated with worse overall and recurrence-free survival in nonmetastatic colorectal cancer. For better oncologic outcomes, our findings indicate a need to reduce the use of blood transfusion during the perioperative period.

Comb-rooted multi-channel synthesis of ultra-narrow optical frequencies of few Hz linewidth

We report a multi-channel optical frequency synthesizer developed to generate extremely stable continuous-wave lasers directly out of the optical comb of an Er-doped fiber oscillator. Being stabilized to a high-finesse cavity with a fractional frequency stability of 3.8 × 10⁻¹⁵ at 0.1 s, the comb-rooted synthesizer produces multiple optical frequencies of ultra-narrow linewidth of 1.0 Hz at 1 s concurrently with an output power of tens of mW per each channel. Diode-based stimulated emission by injection locking is a key mechanism that allows comb frequency modes to sprout up with sufficient power amplification but no loss of original comb frequency stability. Channel frequencies are individually selectable with a 0.1 GHz increment over the entire comb bandwidth spanning 4.25 THz around a 1550 nm center wavelength. A series of out-of-loop test results is discussed to demonstrate that the synthesizer is able to provide stable optical frequencies with the potential for advancing diverse ultra-precision applications such as optical clocks comparison, atomic line spectroscopy, photonic microwaves generation, and coherent optical telecommunications.

Hole-Transporting Side-Chain Polymer Bearing a Thermally Crosslinkable Bicyclo[4.2.0]octa-1,3,5-trien-3-yl Group for High-Performing Thermally Activated Delayed Fluorescence OLED

A new side-chain polymer (X-TPACz) bearing hole-transporting pendant groups accompanying a thermally crosslinkable entity was synthesized using N-([1,1'-biphenyl]-4-yl)- N-(4-(9-(4-vinylbenzyl)-9 H-carbazol-3-yl)phenyl)bicyclo[4.2.0]octa-1(6),2,4-trien-3-amine (6) via addition polymerization. The X-TPACz could be spontaneously crosslinked without using any further reagents and showed a good film-forming property upon low-temperature thermal treatment. The thermal curing temperature for the X-TPACz film was optimized to be 180 °C based on a differential scanning calorimetry thermogram. Moreover, the thermal degradation temperature of X-TPACz measured to be over 467 °C using thermogravimetric analysis demonstrated that it shows excellent thermal stability. In particular, X-TPACz exhibits the highest occupied molecular orbital (HOMO) energy level to be -5.26 eV, which is beneficial for facile hole injection and transportation. Consequently, the thermally activated delayed fluorescence organic light-emitting diodes fabricated using X-TPACz as the hole-transporting material showed state-of-the-art performances with a low turn-on voltage ( V_on) of only 2.7 V and a high external quantum efficiency (EQE) of 19.18% with a high current efficiency (CE) of 66.88 cd/A and a high power efficiency (PE) of 60.03 lm/W, which are highly superior to those of the familiar poly(9-vinylcarbazole) (PVK)-based devices ( V_on = 3.9 V, EQE of 17.42%, with CE of 58.33 cd/A and PE of 33.32 lm/W). The extremely low turn-on voltage and high EQE were found to be due to the higher-lying highest occupied molecular orbital energy level ( E_HOMO = -5.23 eV) and better hole-transporting property of X-TPACz than those of PVK.

Flap Coverage of Dysvascular Digits Including Venous Flow-Through Flaps

A dysvascular digit is defined as a threatened circulatory condition of a digit caused owing to multiple reasons, such as medical illness or trauma. A dysvascular digit always needs surgical manipulation of the vessel in trauma cases. The revascularization of the digit is a priority in such conditions, after which reconstruction of the defect is performed. In this article, the authors present and discuss the venous free flap, thenar free flap, toe plantar free flap, free style perforator flap, hypothenar free flap, and anconeus muscle free flap.

Age-Dependent Variation of Lamina Cribrosa Displacement During the Standardized Valsalva Maneuver

Based on biomechanical theory, lamina cribrosa (LC) displacement, the key component of progressive glaucomatous change, is presumed to be dependent on intraocular pressure (IOP) as well as tissue stiffness of LC. In the performance of the Valsalva maneuver, both IOP and cerebrospinal fluid pressure can increase. The present study investigated the age-dependent variation of LC displacement during the standardized Valsalva maneuver in healthy subjects. Sixty-three (63) eyes (age range: 20-76 years) were prospectively underwent IOP measurement and Cirrus HD-OCT optic disc scans before and during the standardized Valsalva maneuver. During the standardized Valsalva maneuver, the IOP significantly increased from 13.2 ± 2.9 mmHg to 18.6 ± 5.2 mmHg (P < 0.001). The maximal LC depth significantly decreased in the younger age groups (age: 20 s to 40 s) but not in the older age groups (age: over 50). The BMO distance did not change significantly. Younger age (P = 0.009), a smaller increase of IOP during the Valsalva maneuver (P = 0.002), and greater baseline maximal LC depth (P = 0.013) were associated with more anterior displacement of the LC during the standardized Valsalva maneuver. Taken together, age as well as translaminar pressure dynamics seems to play a crucial role in LC biomechanics.

Diurnal change of retinal vessel density and mean ocular perfusion pressure in patients with open-angle glaucoma

Purpose

To investigate, in primary open-angle glaucoma (POAG) and healthy subjects, the pattern and magnitude of diurnal variation in optical coherence tomography angiography (OCTA) retinal vessel density (RVD).

Design

Prospective, observational cross-sectional study.

Participants

A prospective study was conducted on 20POAG patients and 19 healthy subjects.

Methods

Peripapillary/macular RVD (using swept-source OCTA), intraocular pressure (IOP), and systemic blood pressure (BP) were measured five times a day (8 a.m., 11 a.m., 2 p.m.,5 p.m. and 8 p.m.). The magnitudes and patterns of diurnal changes in RVD, diastolic BP, and mean ocular-perfusion pressure (MOPP) were analyzed and compared between the POAG patients and the healthy subjects.

Main outcome measures

The patterns and magnitudes of diurnal RVD change in OCTA.

Results

Intra-visit repeatability (0.755–0.943) and inter-visit reproducibility (0.843–0.986) for the RVD measurements showed excellent reliability. In the POAG patients, the magnitude of diurnal change in peripapillary RVD (9.71±7.04%) and macular RVD (7.22±4.73%) were significantly greater than that in the healthy group (5.73±3.85%, P = 0.013 and 5.51±3.45%, P = 0.042, respectively). The magnitudes of diurnal variations of IOP and MOPP in the POAG group likewise were greater than those in the healthy group (P = 0.003 and 0.039). As for the patterns of diurnal RVD change, interestingly, at 8 p.m., the macular RVD of the healthy group increased to the highest level (44.12±2.95%) while that of the POAG group decreased to the lowest level (40.41±2.54%).

Conclusions

In POAG eyes, diurnal change of IOP, MOPP and RVD was significantly greater than in the healthy eyes. These findings suggest that diurnal RVD changes might reflect the hemodynamic variation of POAG.

Topographic correlation between macular superficial microvessel density and ganglion cell-inner plexiform layer thickness in glaucoma-suspect and early normal-tension glaucoma

BACKGROUND/AIMS

To investigate the topographic relationship between macular superficial microvessel density (SMD) and macular ganglion cell-inner plexiform layer (GCIPL) thickness in eyes with glaucoma-suspect (GS) and early normal-tension glaucoma (NTG).

METHODS

A total of 86 eyes of 86 patients with early NTG (standard automated perimetry mean deviation >-5.5 decibels) and a total of 25 eyes of 25 patients with GS were retrospectively reviewed. All of the subjects underwent optical coherence tomography (OCT) and OCT angiography (OCTA) scan. On the OCTA scan images, macular SMD was analysed by customised software.

RESULTS

In GS and patients with early NTG, macular GCIPL thickness showed significant correlations with macular SMD in the superotemporal (ST), inferotemporal (IT) and inferoinferior (II) sectors (r =0.191, 0.373 and 0.346 for ST, IT and II sector, respectively). Additionally, circumpapillary retinal nerve fibre layer (RNFL) thickness and macular SMD showed significant correlations between the ST sector of the macula and the 1, 9 clock-hour peripapillary regions and between the IT and II sectors of the macula and the 6, 7, 8 clock-hour peripapillary regions. The IT sector macular SMD showed fair diagnostic power (area under the receiver operating characteristic curve [AUROC] = 0.758) and showed high diagnostic power when combined with IT sector macular GCIPL thickness (AUROC=0.954).

CONCLUSIONS

Sectoral macular SMD showed topographic correlations with macular GCIPL thickness and circumpapillary RNFL thickness in patients with GS and early-stage NTG. Macular SMD analysis is potentially useful in the clinical evaluation of early glaucoma.

Exogenous influences on intraocular pressure

Intraocular pressure (IOP), the pressure within the eyeball, is a function mainly of the production and elimination of aqueous humour. Balanced IOP helps to maintain the eyeball contour, allowing proper refraction of light in the anterior segment of the eye. Increases in IOP can cause injury to the ocular structure, typically the optic nerve head and retinal ganglion cells. IOP increase, additionally, is a risk factor for glaucoma progression. However, it is not unusual that glaucoma worsens despite well-managed IOP; indeed, glaucoma can develop and progress even within the normal IOP range. IOP measured once during daytime office hours might not provide sufficient information for effective glaucoma management. In fact, IOP is not a fixed value but rather changes over time: it fluctuates with the intrinsic circadian rhythm and can also change in various lifestyle-related situations (eg, with body posture, during exercise, while holding breath and according to dietary habits). It is therefore worth exploring the various factors that can affect IOP and glaucoma risk. In this review, the various exogenous influences on IOP in the literature are investigated.

Progressive Intrascleral Epithelial Cyst With Intracorneal Extension

The authors report a case of primary sclerolimbal cyst with corneal extension in a 3-year-old boy. The cyst enlarged and dissected into the cornea over time. Surgical excision with tectonic allograft was performed. Preoperative, intraoperative, and postoperative anterior segment findings were shown, and results from histologic and cytologic assays were presented. [J Pediatr Ophthalmol Strabismus. 2019;56:e20-e23.].

Comparison of glaucoma patients referred by glaucoma screening versus referral from primary eye clinic

Purpose

To investigate whether mass glaucoma screening relative to opportunistic case finding at a primary eye clinic is helpful for early detection of glaucoma.

Methods

Subjects referred by glaucoma screening (by non-contact tonometry and non-mydriatic fundus photography; group A, n = 220) and from a primary eye clinic (group B, n = 327) were retrospectively recruited. The positive predictive value (PPV) for glaucoma and the rate of glaucoma awareness were compared. Also, for the newly diagnosed glaucoma (‘definite glaucoma’) patients, the demographics and structural and functional severities of glaucoma were compared.

Results

The PPV for definite glaucoma was 25.5% for group A and 52.4% for group B. The rate of false-positive for ‘glaucoma referral to tertiary hospital’ was significantly higher for group A than for group B (38.6 vs. 18.3%, P < 0.001). Among the definite-glaucoma patients (group A: n = 56; group B: n = 182), the proportion of glaucoma awareness was significantly higher in group B (69.2%) than in group A (8.9%, P < 0.001). The mean deviation (MD) of visual field (VF) was significantly higher in group A than in group B (–3.08 ± 3.99 vs. –6.70 ± 7.29 dB, P_adjusted = 0.040), and the inferior and inferotemporal ganglion cell-inner plexiform layer (GCIPL) thicknesses tended to be greater in group A than in group B, with marginal significance (P_adjusted < 0.10).

Conclusions

Glaucoma screening can be helpful for early detection of glaucoma. However, improvement of the screening strategy is needed in order to enhance its specificity for glaucoma.

Temporal Raphe Sign for Discrimination of Glaucoma from Optic Neuropathy in Eyes with Macular Ganglion Cell-Inner Plexiform Layer Thinning

PURPOSE

To evaluate the potential of the temporal raphe sign on the macular ganglion cell-inner plexiform layer (mGCIPL) thickness map for discriminating glaucomatous from nonglaucomatous optic neuropathy (NGON) in eyes with mGCIPL thinning.

DESIGN

Cross-sectional study.

PARTICIPANTS

A total of 175 eyes of 175 patients with mGCIPL thinning on Cirrus (Carl Zeiss Meditec, Dublin, CA) high-definition OCT were retrospectively included. Glaucoma specialists and neuro-ophthalmology specialists evaluated the patients' medical records for diagnosis of glaucomatous optic neuropathy (GON) or NGON. Finally, by consensus, 67 eyes with GON and 73 eyes with NGON were enrolled.

METHODS

A positive temporal raphe sign was declared in patients in whom there was a straight line longer than one-half of the length between the inner and outer annulus in the temporal elliptical area of the mGCIPL thickness map. Decision tree analysis was performed to formulate a diagnostic model.

MAIN OUTCOME MEASURES

Area under receiver operating characteristic curve (AUC) with sensitivity and specificity.

RESULTS

The temporal raphe sign was observed in 61 of 67 GON eyes (91.0%), but in only 21 of 73 NGON eyes (28.8%) (P < 0.001; chi-square test). On this basis, the diagnostic ability of the temporal raphe sign for discriminating GON from NGON was judged to be good (AUC, 0.811; 95% confidence interval, 0.749-0.874; sensitivity, 91.0%; specificity, 71.2%). The diagnostic performance of the decision tree-based model (AUC 0.879; 95% confidence interval, 0.824-0.933; sensitivity, 88.1%; specificity, 87.7%) was better than that of the temporal raphe sign or the relative afferent pupillary defect (RAPD) alone (P = 0.005, P < 0.001, respectively; DeLong's test). The decision tree model revealed the following: (1) If the temporal raphe sign is positive and the RAPD is absent, the case should be diagnosed as GON; (2) if the temporal raphe sign is absent regardless of the presence or absence of the RAPD, or both the temporal raphe sign and the RAPD are present, the case should be diagnosed as NGON.

CONCLUSIONS

In clinical practice, determining whether the temporal raphe sign appears on OCT macular scans can be a useful tool for discrimination of glaucomatous from nonglaucomatous mGCIPL thinning.

RASAL3 preferentially stimulates GTP hydrolysis of the Rho family small GTPase Rac2

Members of the Ras superfamily of small G-proteins serve as molecular switches of intracellular signaling pathways. Rac2 is a Rho subfamily GTPase switch that is specifically expressed in hematopoietic cells and regulates AKT activation in cell signaling. Ras activating protein-like 3 (RASAL3) is the recently identified Ras GTPase activating protein (GAP) that is also specifically expressed in hematopoietic cells and stimulates p21ras GTPase activity. The restricted expression of both Rac2 and RASAL3 suggests that they may serve critical roles in hematopoietic cell signaling. Here in the present study demonstrates that the catalytic domain of RASAL3 may also be able to interact with Rac2 and stimulate its GTPase activity in vitro. By contrast, p50 rhoGAP molecules did not markedly affect Rac2 GTPase activity, but did accelerate the activity of other Rho GTPases, including Rac1, RhoA and Cdc42. Collectively, the present results indicate, seemingly for the first time, that GAP activity for Rac2 is regulated by the RasGAP family protein, RASAL3.

ALK-positive anaplastic large-cell lymphoma with primary bone involvement: A rare case and review of the literature

Primary bone lymphoma (PBL) is an uncommon type of extranodal lymphoma involvement. An anaplastic large-cell lymphoma (ALCL) is an extremely rare type of PBL, and it remains unclear whether ALCLs that primarily involve the bone exhibit favourable or unfavourable biological behaviour, and whether they are similar to ALCLs in general, or not. We reported a case of ALK-positive ALCL with primary bone involvement, and reviewed the clinicopathological features of 22 previously reported cases. An ALCL with primary bone involvement mostly affects younger patients with a preponderant towards the involvement of axial-bone. The prognosis of an ALCL that primarily involves bone is unfavourable, compared with PBL generally. The ALK-positive ALCLs in PBLs had less decedents than the ALK-negative ALCLs with a statistical non-significance (p=0.198).

Prognostic factor determination mortality of acute glufosinate-poisoned patients

Background:

Glufosinate-containing herbicide is increasingly used in agriculture. Its poisoning is a worldwide concern. More and more patients are poisoned by glufosinate. The aim of this study was to determine the factors associated with mortality of patients with acute poisoning of glufosinate.

Methods:

This was a retrospective cohort study conducted from January 1998 to October 2015. Using a multivariate logistic analysis, data for the total population were retrospectively analyzed to determine the factors associated with mortality. Various variables were compared in survivors and non-survivors. Significant predictive variables, Acute Physiology and Chronic Health Evaluation (APACHE) II scoring system, the Simplified Acute Physiology Score (SAPS) II, and Sequential Organ Failure Assessment (SOFA) score were compared by analyzing receiver operating characteristic (ROC) curves.

Results:

A total of 253 patients (mean age: 58 years) were enrolled. Of the 253 patients, 219 (86.6%) survived and 34 (13.4%) died. Decreased Glasgow Coma Scale (GCS) and bicarbonate (HCO3−), use of mechanical ventilator, and use of vasopressors (dopamine, dobutamine, norepinephrine) were associated with mortality. The areas under the curve in the ROC curve analysis for the predictive variables, SOFA score, APACHE II scoring system, and SAPS II were 0.952, 0.829, 0.927, and 0.944, respectively.

Conclusion:

Four predictive variables (GCS < 9, HCO3− < 16.0 mmol/L, mechanical ventilator apply, and use of vasopressors) were associated with mortality in the total population of patients with acute poisoning of glufosinate. These predictive variables had good discriminative power for predicting mortality of patients with acute poisoning of glufosinate-containing herbicide compared to APACHE II, SOFA, and SAPS II.

Nonlinear third harmonic generation at crystalline sapphires

Third harmonic generation (THG) is a nonlinear optical phenomenon which can be applied in diverse research areas including interfacial studies, sub-wavelength light manipulation, and high sensitivity bio-molecular detection. Most precedent studies on THG have focused on dielectric and metallic materials, including silicon, gold, and germanium, due to their high nonlinear susceptibility. Sapphire, a widely-used optical substrate, has not been studied in depth for its third harmonic characteristics, despite its excellent optical transmission in the UV-visible range, high thermal conductance, and superior physical and chemical stability. In this research, we comprehensively studied THG at thin air-dielectric interfaces of sapphire wafers by controlling the wafer cutting planes, focusing depth, incidence angle, laser intensity, and input polarization of the input laser beam. These findings can lead to broader use of third harmonics for high-precision sapphire characterization, such as surface quality inspection, crystallinity determination, interfacial studies, delamination check, and real-time monitoring of crack propagation.