Agreement and precision of wide and cube scan measurements between swept-source and spectral-domain OCT in normal and glaucoma eyes.

This study aimed to evaluate agreement of Wide scan measurements from swept-source optical coherence tomography (SS-OCT) Triton and spectral-domain OCT (SD-OCT) Maestro in normal/glaucoma eyes, and to assess the precision of measurements from Wide and Cube scans of both devices. Three Triton and three Maestro operator/device configurations were created by pairing three operators, with study eye and testing order randomized. Three scans were captured for Wide (12 mm × 9 mm), Macular Cube (7 mm × 7 mm-Triton; 6 mm × 6 mm-Maestro), and Optic Disc Cube (6 mm × 6 mm) scans for 25 normal eyes and 25 glaucoma eyes. Parameter measurements included circumpapillary retinal nerve fiber layer(cpRNFL), ganglion cell layer + inner plexiform layer (GCL+), and ganglion cell complex (GCL++). A two-way random effect analysis of variance model was used to estimate the repeatability and reproducibility; agreement was evaluated by Bland-Altman analysis and Deming regression. The precision estimates were low, indicating high precision, for all thickness measurements with the majority of the limits < 5 µm for the macula and < 10 µm for the optic disc. Precision of the Wide and Cube scans were comparable. Excellent agreement between the two devices was found for Wide scans, with the mean difference < 3 µm across all measurements (cpRNFL < 3 µm, GCL+ < 2 µm, GCL ++ < 1 µm), indicating interoperability. A single Wide scan covering the peripapillary and macular regions may be useful for glaucoma diagnosis and management.

Agreement and Precision of Wide and Cube Scan Measurements between Swept-source and Spectral-domain OCT in Normal and Glaucoma Eyes.

This study aimed to evaluate agreement of Wide scan measurements from swept-source optical coherence tomography(SS-OCT) Triton and spectral-domain OCT(SD-OCT) Maestro in normal/glaucoma eyes, and to assess the precision of measurements from Wide and Cube scans of both devices. Three Triton and three Maestro operator/device configurations were created by pairing three operators, with study eye and testing order randomized. Three scans were captured for Wide (12mm×9mm), Macular Cube (7mmx7mm-Triton; 6mmx6mm-Maestro), and Optic Disc Cube (6mmx6mm) scans for 25 normal eyes and 25 glaucoma eyes. Thickness of circumpapillary retinal nerve fiber layer(cpRNFL), ganglion cell layer+inner plexiform layer(GCL+), and ganglion cell complex(GCL++) was obtained from each scan. A two-way random effect analysis of variance model was used to estimate the repeatability and reproducibility; agreement was evaluated by Bland-Altman analysis and Deming regression. Precision limit estimates were low: <5µm for macular and <10µm for optic disc parameters. Precision for Wide and Cube scans of both devices were comparablein both groups. Excellent agreement between the two devices was found for Wide scans, with the mean difference<3µm across all measurements (cpRNFL<3µm, GCL+<2µm, GCL++<1µm), indicating interoperability. A single Wide scan covering the peripapillary and macular regions may be useful for glaucoma management.

Macula structural and vascular differences in glaucoma eyes with and without high axial myopia.

AIMS: To identify clinically relevant parameters for identifying glaucoma in highly myopic eyes, an investigation was conducted of the relationship between the thickness of various retinal layers and the superficial vessel density (sVD) of the macula with axial length (AL) and visual field mean deviation (VFMD). METHODS: 270 glaucoma patients (438 eyes) participating in the Diagnostic Innovations in Glaucoma cross-sectional study representing three axial myopia groups (non-myopia: n=163 eyes; mild myopia: n=218 eyes; high myopia (AL>26 mm): n=57 eyes) who completed macular optical coherence tomography (OCT) and OCT-angiography imaging were included. Associations of AL and VFMD with the thickness of the ganglion cell inner plexiform layer (GCIPL), macular retinal nerve fibre layer (mRNFL), ganglion cell complex (GCC), macular choroidal thickness (mCT) and sVD were evaluated. RESULTS: Thinner Global GCIPL and GCC were significantly associated with worse VFMD (R2=34.5% and R2=32.9%; respectively p<0.001), but not with AL (all p>0.1). Thicker mRNFL showed a weak association with increasing AL (R2=2.4%; p=0.005) and a positive association with VFMD (global R2=19.2%; p<0.001). Lower sVD was weakly associated with increasing AL (R2=1.8%; p=0.028) and more strongly associated with more severe glaucoma VFMD (R2=29.6%; p<0.001). Thinner mCT was associated with increasing AL (R2=15.5% p<0.001) and not associated with VFMD (p=0.194). mRNFL was thickest while mCT was thinnest in all sectors of high myopic eyes. CONCLUSIONS: As thinner GCIPL and GCC were associated with increasing severity of glaucoma but were not significantly associated with AL, they may be useful for monitoring glaucoma in highly myopic eyes.

Relative Stability of Regional Facial and Ocular Temperature Measurements in Healthy Individuals.

Purpose: Non-contact measurement of facial temperature using infrared thermography has been used for mass screening of body temperature during a pandemic. We investigated the relative stability of temperature measurement in different facial regions of healthy individuals. Methods: Twenty healthy subjects underwent two experiments. In the first experiment, subjects washed their faces with a 20°C wet towel for 1 minute. Temperature changes compared to baseline in the forehead, cornea, inner canthus, and outer canthus were determined using an infrared camera for 10 minutes. In the second experiment, lubricating eye drops at 20°C were instilled over one eye. Temperature changes in the same regions of interest were monitored for 5 minutes. Results: Baseline temperatures before face washing in the forehead and cornea, inner canthus, and outer canthus of the right eye were 33.4°C ± 0.8°C (mean ± SD), 33.3°C ± 0.8°C, 34.3°C ± 0.7°C, and 32.8°C ± 0.7°C, respectively. Reductions in temperature due to face washing were most significant for the forehead and least significant for the cornea. One minute after face washing, the corresponding changes were -2.8°C ± 0.6°C, -0.3°C ± 0.6°C, -0.6°C ± 0.7°C, and -0.9°C ± 0.7°C for the forehead, cornea, inner canthus, and outer canthus, respectively. After administering the eye drops, no significant temperature changes were observed. Conclusions: When facial temperature was exogenously cooled, the cornea had the most stable temperature readings. Translational Relevance: When using infrared thermography to screen facial temperature, the measurement of corneal temperature is probably a better representative if the stability of temperature readings is critical.

Effect of topical latanoprost on choroidal thickness and vessel area in Guinea pigs.

The aim of this study was to investigate the effect of latanoprost, an ocular hypotensive agent and prostaglandin analog, on choroidal thickness and structure in young adult guinea pigs. Young (three-month-old) guinea pigs (n = 10) underwent daily monocular treatment with topical 0.005% latanoprost for 2 weeks, followed by a washout period of 2 weeks. Tonometry (iCare) and retinoscopy were undertaken to monitor intraocular pressure (IOP) and refractive error (recorded as spherical equivalent refractive error; SER), respectively. Axial length (AL) and choroidal thickness (ChT) were measured using high frequency A-scan ultrasonography, with additional ChT data, as well as choroidal vessel (ChV) areas obtained from posterior segment imaging using Spectral Domain-Optical Coherence Tomography (SD-OCT). Image J was used to analyze SD-OCT images. As expected, latanoprost significantly reduced IOP in treated eyes. Mean interocular IOP difference (±SE) changed from -0.40 ± 0.31 mmHg at baseline to -2.23 ± 0.43 mmHg after 2 weeks of treatment (p = 0.05). However, SER and AL were unaffected; interocular difference changed from 0.41 ± 0.58 to 0.38 ± 0.43 D and from -0.002 ± 0.02 mm to -0.007 ± 0.01 mm (p > 0.05), respectively. Latanoprost had minimal effect on ChT. Interocular ChT differences were 0.01 ± 0.06 µm at baseline and 0.04 ± 0.06 µm after 2 weeks of treatment (SD-OCT; p > 0.05). However, treated eyes had significant increased ChV areas; interocular differences changed from -0.76 ± 69.2 to 100.78 ± 66.9 µm2 after treatment (p = 0.04). While this study was limited to otherwise untreated young adult guinea pigs, the possibility that choroidal vessel enlargement contributes to the previously reported inhibitory effect of topical latanoprost on myopia progression in young guinea pigs warrants investigation.

Comparison of Optic Disc Ovality Index and Rotation Angle Measurements in Myopic Eyes Using Photography and OCT Based Techniques.

Purpose: To compare optic nerve head (ONH) ovality index and rotation angle measurements based on semi-automated delineation of the clinical ONH margin derived from photographs and automated BMO configuration derived from optical coherence tomography (OCT) images in healthy and glaucomatous eyes with high-, mild- and no axial myopia. Methods: One hundred seventy-five healthy and glaucomatous eyes of 146 study participants enrolled in the Diagnostic Innovations in Glaucoma Study (DIGS) with optic disc photographs and Spectralis OCT ONH scans acquired on the same day were stratified by level of axial myopia (non-myopic [n = 56, axial length (AL) <24 mm], mild-myopic [n = 58, AL 24-26 mm] and high-myopic [n = 32, AL >26 mm]. The clinical disc margin of each photograph was manually annotated, and semi-automated measurements were recorded of the ovality index and rotation angle based on a best-fit ellipse generated using ImageJ software. These semi-automated photograph-based measurements were compared to ovality index and rotation angle generated from custom automated BMO-based analysis using segmented OCT ONH volumes. R 2 values from linear mixed effects models were used to describe the associations between semi-automated, photograph-based and automated OCT-based measurements. Results: Average (95% CI) axial length was 23.3 (23.0, 23.3) mm, 24.8 (24.7, 25.0) mm and 26.8 (26.6, 27.0) mm in non-myopic, mild-myopic and high-myopic eyes, respectively (ANOVA, p ≤ 0.001 for all). The R 2 association (95% CI) between semi-automated photograph-based and automated OCT-based assessment of ONH OI for all eyes was [0.26 (0.16, 0.36); p < 0.001]. This association was weakest in non-myopic eyes [0.09 (0.01, 0.26); p = 0.02], followed by mild-myopic eyes [0.13 (0.02, 0.29); p = 0.004] and strongest in high-myopic eyes [0.40 (0.19, 0.60); p < 0.001]. No significant associations were found between photography- and OCT-based assessment of rotation angle with R 2 values ranging from 0.00 (0.00, 0.08) in non-myopic eyes to 0.03 (0.00, 0.21) in high-myopic eyes (all associations p ≥ 0.33). Conclusions: Agreement between photograph-based and automated OCT-based ONH morphology measurements is limited, suggesting that these methods cannot be used interchangeably for characterizing myopic changes in the ONH.

Comparison of the Effects of Latanoprostene Bunod and Timolol on Retinal Blood Vessel Density: A Randomized Clinical Trial.

PURPOSE: To compare the differences in retinal vessel density (VD) between topical administration of latanoprostene bunod (LBN) ophthalmic solution 0.024% and timolol maleate 0.5% in patients with open-angle glaucoma (OAG) or ocular hypertension (OHT) and normal subjects. DESIGN: Randomized, single center, crossover clinical trial. METHODS: Eligible subjects were examined during 6 study visits over 12 weeks. All subjects were randomized in a 1:1 ratio to LBN dosed once daily or timolol dosed twice daily in both eyes (OU) for a duration of 4 weeks each, separated by a 2-week washout period. A comprehensive eye examination OU was performed at each visit. Testing was performed with optical coherence tomography and optical coherence tomography angiography (optic nerve and macula), as well as visual field examination, on the study eye at baseline and before and after each treatment. RESULTS: One eye from each of 50 patients was enrolled (10 healthy patients, 26 patients with OHT, and 14 patients with OAG). After administration of LBN there was significantly increased macular VD (0.76% [0.20%-1.33%], P = 0.009) and a trend in increasing peripapillary VD in patients with OAG and patients with OHT. In contrast, after administration of timolol, there were no differences in macular VD, and a decrease in peripapillary VD only was observed in the nasal inferior sector (-0.56% [-1.08% to -0.03%], P = .04) in patients with OAG and patients with OHT. No change in peripapillary or macular VD was observed in the normal subjects (P > .05 for all). CONCLUSIONS: Topical administration of LBN enhanced macular VD in patients with OAG or patients with OHT. In contrast, timolol administration did not have any effect on VD.

OCT-Angiography Face Mask-Associated Artifacts During the COVID-19 Pandemic.

PRCIS: Face mask wearing has no significant effects on artifacts or vessel density measurements in optic nerve head (ONH) and macular optical coherence tomography-angiography (OCT-A) scans. PURPOSE: The aim was to assess the difference in area of artifacts observed in optical OCT-A scans with and without face mask wear and to verify if mask wear interferes with OCT-A vessel density measurements. SUBJECTS AND CONTROLS: A total of 64 eyes of 10 healthy subjects, 4 ocular hypertensive, 8 glaucoma suspects, and 17 glaucoma patients were included. MATERIALS AND METHODS: High-density ONH and macula OCT-A scans were obtained in patients with and without surgical masks. Seven different artifacts (motion, decentration, defocus, shadow, segmentation failure, blink, and Z-offset) were quantitatively evaluated by 2 trained graders. The changes in the area (% of scan area) of artifacts, without and with mask wearing, and differences of vessel density were evaluated. RESULTS: Trends of increasing motion artifact area for the ONH scans [4.23 (-0.52, 8.98) %, P=0.08] and defocus artifact area for the macular scans [1.06 (-0.14, 2.26) %, P=0.08] were found with face mask wear. However, there were no significant differences in the mean % area of any artifacts (P>0.05 for all). Further, the estimated mean difference in vessel density in images acquired without and with masks was not significant for any type of artifact. CONCLUSION: Face mask wearing had no significant effect on area of artifacts or vessel density measurements. OCT-A vessel density measurements can be acquired reliably with face mask wear during the pandemic.

Racial Differences in Detection of Glaucoma Using Retinal Nerve Fiber Layer Thickness and Bruch Membrane Opening Minimum Rim Width.

PURPOSE: To compare the sensitivities and specificities of the retinal nerve fiber layer thickness (RNFLT) and Bruch membrane opening minimum rim width (BMO-MRW) reference database-based criteria for detection of glaucoma in individuals of European descent (ED) and individuals of African descent (AD). DESIGN: Comparative diagnostic analysis by race METHODS: 382 eyes of 255 glaucoma patients (ED = 170, AD = 85) and 94 eyes of 50 healthy individuals (ED = 30, AD = 20) with global and sectoral RNFLT and BMO-MRW measured with Spectralis optical coherence tomography (OCT) were included. Six diagnostic criteria were evaluated: global measurement below the 5th or 1st percentile, ≥1 of the 6 sector measurements below the 5th or 1st percentile, and superotemporal (ST) and/or inferotemporal (IT) measurement below the 5th or 1st percentile. The sensitivities and specificities of these measurements for detection of glaucoma were compared using bootstrapping methods. RESULTS: ST and/or IT RNFLT below the 5th percentile has the best performance for detection of glaucoma among RNFLT classifications with a sensitivity (95% CI) of 89.5% (86.1, 92.5) and specificity of 87.2% (77.8, 95.1). In AD individuals, sensitivities of ST and IT RNFLT and BMO-MRW measurements below the 5th percentile criteria were lower than in ED individuals (RNFLT: 83.7% vs 92.5%, and BMO-MRW: 72.1% vs 88.5%, respectively), as well as specificities (AD RNFLT: 73.7% and BMO-MRW: 89.5% vs ED RNFLT: 96.4% and BMO-MRW: 98.2%, respectively). CONCLUSIONS: RNFLT and BMO-MRW had consistently lower diagnostic performance in AD individuals compared with ED individuals. BMO-MRW criteria might fail to detect as many as one-third of eyes with glaucoma, specifically in AD individuals. With the current reference database, RNFLT, and especially BMO-MRW, criteria are not adequate for diagnosing glaucoma in AD individuals.

Agreement between Compass Fundus Perimeter New Grid and 10-2 Testing Protocols for Detecting Central Visual Field Defects.

PURPOSE: To evaluate the agreement between Compass New Grid (NG) and 10-2 test protocols for detecting early glaucomatous defects in the central 10 degrees of the visual field (CVFD). DESIGN: Cross-sectional study. PARTICIPANTS: A total of 123 eyes of 14 healthy individuals, 17 glaucoma suspects, and 32 glaucoma patients were enrolled. METHODS: Subjects performed NG and 10-2 Compass automated perimetry testing within 1 week. For both test protocols, total deviation (TD) and pattern deviation (PD) plot CVFDs were defined by 3 contiguous points with probabilities of <5%, <2%, <2% or <5%, <1%, <1%. Cohen's Kappa statistic was used to assess agreement between NG and 10-2 for identifying CVFDs. The Spectralis GMPE Hood Glaucoma Report (investigational software version) macula deviation analysis obtained within 1 year was used for calculating sensitivities and specificities of test protocols. MAIN OUTCOME MEASURES: Protocols' agreement, sensitivity, and specificity. RESULTS: Fair to moderate agreement was observed between NG and 10-2 protocols for detecting presence of superior CVFDs on TD (k = 0.57) and PD (k = 0.26) plots and for detecting inferior CVFDs on TD (0.49) and PD (0.27) plots. With the use of OCT macula deviation maps, specificity for detecting CVFD was consistently higher with NG than 10-2 tests for TD plots of the superior hemifield (0.82 and 0.65), inferior hemifield (0.92 and 0.84), and PD plots of the superior hemifield (0.81 and 0.36) and inferior hemifield (0.86 and 0.52). Sensitivity of NG was consistently lower than TD plots of the superior hemifield (0.48 and 0.72), inferior hemifield (0.28 and 0.46), and PD plots of the superior hemifield (0.48 and 0.78) and inferior hemifield (0.20 and 0.52). By using pattern standard deviation (PSD) criterion, the mean PSD values for 10-2 and NG VF tests were 1.61 (95% confidence interval [CI], 1.26-1.96) and 1.81 (95% CI, 1.45-2.17) (P < 0.001), respectively. CONCLUSIONS: Although the Compass NG detected fewer CVFDs than the 10-2 test protocol, it did detect CVFDs that were not observed in the Compass 24-2 test in patients with early glaucoma. Therefore, NG may be particularly useful in clinical situations when higher specificity is desired or PSD criterion is used.

Superficial and Deep Macula Vessel Density in Healthy, Glaucoma Suspect, and Glaucoma Eyes.

PRECIS: Macular superficial capillary plexus (SCP) vessel density is more informative than deep capillary plexus (DCP) vessel density for the detection of glaucoma. PURPOSE: The purpose of this study was to characterize optical coherence tomography angiography macular SCP and projection-resolved DCP vessel densities and compare their diagnostic accuracies with ganglion cell complex (GCC) thickness in healthy, glaucoma suspect, and glaucoma eyes. MATERIALS AND METHODS: Sixty-eight eyes of 44 healthy subjects, 26 eyes of 16 preperimetric glaucoma suspects, and 161 eyes of 124 glaucoma patients from the Diagnostics Innovations in Glaucoma Study with good quality high-density 6×6 mm2 macula optical coherence tomography angiography images were included. The diagnostic accuracy of SCP vessel density, projection-resolved DCP vessel density and GCC thickness were compared among groups. RESULTS: Mean whole image vessel density (wiVD; % of area occupied by vessels containing flowing blood) in the SCP layer was highest in healthy eyes (49.7%), followed by glaucoma suspect eyes (46.0%), and glaucoma eyes (40.9%) (P<0.001). Mean wiVD in the DCP layer was similar in healthy (50.6%), glaucoma suspect (47.3%), and glaucoma eyes (45.7%) (P=0.925). Diagnostic accuracy of both GCC thickness and SCP wiVD was significantly higher than DCP wiVD for classifying healthy and glaucoma eyes [adjusted area under the receiver operating characteristic curve (95% confidence interval): GCC=0.86 (0.72, 0.94), SCP=0.80 (0.66, 0.91) and DCP=0.44 (0.30, 0.57)] (P<0.001). CONCLUSIONS: SCP vessel densities have better diagnostic accuracy for detecting glaucoma than DCP vessel densities. Although the diagnostic accuracy of the macula SCP is relatively modest, it is more informative than the DCP.

Aeromedical evacuation: experiences from the UK military level 2 hospital in Bentiu, South Sudan, during Op TRENTON.

INTRODUCTION: Aeromedical Evacuation (AE) is a vital role of the Defence Medical Services (DMS). With a far-reaching defence global footprint, an AE capability is crucial to enable movement of patients in the fastest, safest and least stressful way that meets or exceeds the level of care an injured or ill person may expect to receive in the UK. Operation (Op) TRENTON is a UK military humanitarian operation in support of the United Nations (UN) Mission in South Sudan. METHODS: A retrospective analysis was carried out of all patients who underwent AE from the UK level 2 hospital at Bentiu during Op TRENTON over a 17-month period from June 2017 to October 2018. RESULTS: 14 patients underwent AE. The median age was 36 (22-64) years and all patients were male. 21% of AEs were for UK personnel and 79% were for UN personnel. 29% of AEs were due to non-battle injury with the remainder due to disease. Musculoskeletal was the largest diagnostic group (n=4) followed by respiratory (n=3), cardiovascular (n=2), undifferentiated febrile illness (n=2), neurology (n=1), renal medicine (n=1) and psychiatry (n=1). CONCLUSIONS: Patients requiring AE from the level 2 hospital at Bentiu mostly had musculoskeletal and medical pathology, a stark contrast to the trauma patient cohort from operations in the past. The majority of patients had definitive care under the medical team highlighting the requirement for DMS physicians and the AE team, to be trained in acute, general and aviation medicine. The majority of AE moves were for UN personnel and on UN airframes, highlighting the importance of a sound understanding of the nations we are working with.

Evaluating the neuroprotective impact of senolytic drugs on human vision.

Glaucoma, a chronic neurodegenerative disease of retinal ganglion cells (RGCs), is a leading cause of irreversible blindness worldwide. Its management currently focuses on lowering intraocular pressure to slow disease progression. However, disease-modifying, neuroprotective treatments for glaucoma remain a major unmet need. Recently, senescent cells have been observed in glaucomatous eyes, exposing a potential pathway for alternative glaucoma therapies. Prior studies demonstrated that targeting senescent RGCs for removal (i.e., a senolytic approach) protected healthy RGCs and preserved visual function in a mouse ocular hypertension model. However, the effects of senolytic drugs on vision in human patients are unknown. Here, we used existing clinical data to conduct a retrospective cohort study in 28 human glaucoma patients who had been exposed to senolytics. Senolytic exposure was not associated with decreased visual acuity, elevated intraocular pressure, or documentation of senolytic-related adverse ocular effects by treating ophthalmologists. Additionally, patients exposed to senolytics (n = 9) did not exhibit faster progression of glaucomatous visual field damage compared to matched glaucoma patients (n = 26) without senolytic exposure. These results suggest that senolytic drugs do not carry significant ocular toxicity and provide further support for additional evaluation of the potential neuroprotective effects of senolytics on glaucoma and other neurodegenerative diseases.

Visual Field Artifacts in Glaucoma With Face Mask Use During the COVID-19 Pandemic.

PURPOSE: The coronavirus (COVID-19) pandemic has changed how outpatient care is delivered in ophthalmology clinics, particularly with glaucoma care. This case series highlights the need for awareness of fogging and improper face mask fit as causes of standard automated perimetry artifacts in patients with ocular hypertension and glaucoma. CLINICAL PRESENTATIONS: Six patients with the diagnosis of ocular hypertension, glaucoma suspect, or glaucoma underwent standard automated perimetry (24-2 or 10-2 SITA, Humphrey Field Analyzer) while wearing ear-loop surgical face masks. Due to patient complaints of fogging during the testing, low test reliability, and unexpected results, the tests were repeated after taping securely the mask to the bridge of the nose. CLINICAL FINDINGS: Fogging may reduce visual field (VF) test reliability and induce artifacts that mimic glaucomatous defects. VF test reliability can be improved and artifacts minimized following mask taping. In 1 case there was worsening of VF defects after mask taping. This suggests that fogging may also disguise true VF defects. CONCLUSIONS: Fogging can result in unreliable VF testing with glaucoma-like artifacts. Secure taping of the face mask to the nose bridge may minimize this problem and reduce unnecessary additional testing and follow-up visits.

Effect of chronic topical latanoprost on the sclera and lamina cribrosa of form-deprived myopic Guinea pigs.

The purpose of this study was to investigate the effects of latanoprost, an ocular hypotensive prostaglandin analog, on scleral collagen fibers and laminar pores in myopic guinea pigs. Young guinea pigs underwent monocular form deprivation (FD; white plastic diffusers) from 14-days of age for 10-weeks. After the first week, FD eyes also received daily topical A) latanoprost (Lat, 0.005%, n = 5) or B) artificial tears (AT; n = 5). At the end of the treatment period, animals were sacrificed, eyes enucleated and optic nerve heads (ONH) excised to include a 4 mm diameter ring of surrounding sclera for scanning electron microscopy (SEM), and an additional 6 mm ring of sclera surrounding the ONH was excised for transmission electron microscopy (TEM). For SEM, ONH samples were first immersed in 0.2M NaOH for 30 h to isolate the collagenous structures. All samples were stained with osmium tetroxide, dried through an ethanol series and finally subjected to critical point drying before imaging. Image J was used to analyze the dimensions of laminar pores (SEM images) and scleral collagen fibers (TEM images). As previously reported in a related study, latanoprost was effective in inhibiting myopia progression in FD eyes of the guinea pigs. The scleral fibers of FD myopic eyes treated with AT were smaller and more variable in cross-sectional areas compared to untreated (fellow) eyes (mean areas: 0.0059 ±â€¯0.0013 vs. 0.0085 ±â€¯0.002 µm2; p < 0.001), consistent with scleral changes reported for human myopia. In contrast, the scleral fibers of the Lat-treated FD eyes were similar to those of fellow eyes (0.0083 ±â€¯0.002 vs. 0.0078 ±â€¯0.0014 µm2). However, laminar pore size appeared unaffected by either the FD or drug treatments, with no significant difference found between FD eyes and their fellows, for either treatment group. That daily topical latanoprost appeared to protect against myopia-related changes in scleral collagen, rather than exaggerating them, as might be predicted from its known action on the uveoscleral extracellular matrix, lends further support its use for myopia control. In this guinea pig myopia model, the lamina cribrosa appeared unaffected.

The effect of part-time wear of 2-zone concentric bifocal spectacle lenses on refractive error development & eye growth in young chicks.

The purpose of this study is to characterize in young chicks the myopia control effects of part-time wear of two-zone concentric bifocal lenses. Nine-day-old chicks (n = 115) were first made myopic with monocular -10 Diopter (D) single vision (SV) lenses worn for 3 days. Over the 6 days following myopia induction, either 1) two-zone bifocal lenses (-10 D center/-5 D periphery, BFDC) were worn for 12 (full-time), 10, 8, or 6 h, with -10 D SV lenses worn for the remainder of the day, or 2) BFDC or BFNC (-5 D center/-10 D periphery) lenses were worn every other day (EOD). Control birds wore -10 D SV lenses every day. Refractive error (RE) and axial ocular dimensions were monitored every three days with retinoscopy and high frequency A-scan ultrasonography respectively. Mean interocular RE and axial length differences after 3 days of myopia induction (±SEM) were -9.6 ±â€¯0.19 D and 0.26 ±â€¯0.01 mm across the groups. At the end of the following 6-day treatment period, equivalent values were: -10.66 ±â€¯0.28 D, 0.42 ±â€¯0.02 mm (SV-control); 1) -4.61 ±â€¯0.29 D, 0.26 ±â€¯0.02 mm (BFDC, 12 h); -4.82 ±â€¯0.23 D, 0.28 ±â€¯0.02 mm (BFDC, 10 h); -5.21 ±â€¯0.27 D, 0.24 ±â€¯0.02 mm (BFDC, 8 h); -6.34 ±â€¯0.34 D, 0.25 ±â€¯0.03 mm (BFDC, 6 h); 2) -8.29 ±â€¯0.29 D, 0.32 ±â€¯0.03 mm (BFDC, EOD), and -8.83 ±â€¯0.36 D, 0.33 ±â€¯0.03 mm (BFNC, EOD). Overall, full-time BFDC and part-time BFDC and BFNC lens groups exhibited similar changes and were less myopic than the SV group. The results suggest that bifocal lenses may have myopia control effects even when worn part-time, interleaved with standard (SV) myopic corrections, especially if worn for at least 6 h per day.

Effects of Topical Latanoprost on Intraocular Pressure and Myopia Progression in Young Guinea Pigs.

Purpose: To determine whether latanoprost, a prostaglandin analog proven to be very effective in reducing intraocular pressure (IOP) in humans, can also slow myopia progression in the guinea pig form deprivation (FD) model. Methods: Two-week-old pigmented guinea pigs underwent monocular FD and daily topical latanoprost (0.005%, n = 10) or artificial tears (control, n = 10) starting 1 week after the initiation of FD, with all treatments continuing for a further 9 weeks. Tonometry, retinoscopy, and high-frequency A-scan ultrasonography were used to monitor IOP, refractive error, and ocular axial dimensions, respectively. Results: Latanoprost significantly reduced IOP and slowed myopia progression. Mean interocular IOP differences (±SEM) recorded at baseline and week 10 were -0.30 ± 0.51 and 1.80 ± 1.16 mm Hg (P = 0.525) for the control group and 0.07 ± 0.35 and -5.17 ± 0.96 mm Hg (P < 0.001) for the latanoprost group. Equivalent interocular differences for optical axial length at baseline and week 10 were 0.00 ± 0.015 and 0.29 ± 0.04 mm (P < 0.001; control) and 0.02 ± 0.02 and 0.06 ± 0.02 mm (P = 0.202; latanoprost), and for refractive error were +0.025 ± 0.36 and -8.2 ± 0.71 diopter (D) (P < 0.001; control), and -0.15 ± 0.35 and -2.25 ± 0.54 D (P = 0.03; latanoprost). Conclusions: In the FD guinea pig model, latanoprost significantly reduces the development of myopia. Although further investigations into underlying mechanisms are needed, the results open the exciting possibility of a new line of myopia control therapy.

Bullous Skin Manifestations of Mycoplasma pneumoniae Infection: A Case Series.

Bullous skin lesions are uncommon in children. While it is well known that Mycoplasma infections are associated with papular skin manifestations, bullous skin lesions are not commonly reported. Mycoplasma pneumoniae is a very common bacterial pathogen causing respiratory tract infection in children and adults. We report 2 children with serology-confirmed Mycoplasma infection who were hospitalized for blistering skin lesions. Both of our patients responded well to corticosteroids and one of them required intravenous immunoglobulin. The aim of this case report is to raise awareness that Mycoplasma pneumoniae infection can present with bullous skin lesions, and to briefly review the pathophysiology, diagnosis, and management of the skin manifestation of Mycoplasma infection.