Corneal thickness and endothelial change after use of ocular hypotensive agents.

Corneal transplantation can restore visual function when visual impairment is caused by a corneal disease. However, this treatment is associated with the scarcity of cornea donors. The suitability of corneal donation from patients with glaucoma using ocular hypotensive agents (OHAs) is controversial. This study aimed to elucidate changes in corneal thickness, corneal endothelial cell density, and corneal endothelial cell hexagonality after OHA use in patients with primary open-angle glaucoma. We retrospectively reviewed the data of 53 glaucoma suspect eyes without OHA use and 106 primary open-angle glaucoma eyes under OHA use. All participants underwent corneal parameter assessment using SP-3000P (Topcon Corp., Tokyo, Japan) at the time of diagnosis and the final visit. The OHA dose and timing of use were recorded. The ocular hypotensive agents score (OHAS) was determined based on the number, formula, frequency, and duration of OHA use. Baseline data showed no significant differences between the two groups with and without OHA use. At the final visit, the OHA-treated group showed significantly lower corneal thickness and corneal endothelial cell density than those of the control group. A weak positive correlation between the OHAS and changes in corneal endothelial cell hexagonality was noted. However, no correlation was observed between the OHAS and changes in corneal thickness or endothelial cell density. In conclusion, patients with glaucoma and using OHAs should undergo the corneal structural properties examinations before donation to ensure the quality of donor cornea.

Comparing Tear Film Viscosity between Sjögren and Non-Sjögren Dry Eye Disease.

This study aimed to compare tear film viscosity (TFV) in Sjögren and non-Sjögren dry eye diseases (DEDs). This was a cross-sectional observational study. A total of 68 DED patients were enrolled, including 32 patients with Sjögren syndrome (SS) and 36 without SS. TFV was assessed by a tear film analyzer and determined by the momentary moving speed (MMS; MMS (t) = α × t-ß, t = time (s)) with its power-law fitting-derived parameters (α and ß). Among the four indices of TFV (MMS (0.1 s), MMS (2.0 s), α, and ß), the SS-DED patients had significantly lower MMS (0.1 s) (p = 2.01 × 10-5), α (p = 0.0375), and ß (p = 0.0076). The SS-DED group also had significantly higher OSDI, lower central and nasal tear meniscus height (TMH), and higher OSS. MMS (0.1 s) was significantly correlated with nasal TMH and OSS (ρ = 0.2520, p = 0.0381 in nasal TMH; ρ = -0.3487, p = 0.0036 in OSS). Index ß was not correlated with any non-TFV tests. In conclusion, MMS (0.1 s), α, and ß are promising TFV indices in distinguishing SS-DED from non-SS-DED patients early. Among these TFV indices, lower MMS is the best alternative clue for detecting SS-DED.

Corneal Complications after COVID-19 Vaccination: A Systemic Review.

Multiple vaccines are now being used across the world, and several studies have described cases of corneal graft rejection following the administration of the COVID-19 vaccine. The purpose of this article is to review the corneal adverse event that occurred following COVID-19 vaccine administration. The literature search was conducted in March 2022 using MEDLINE, PubMed, and the Cochrane Database of Systematic Reviews. A total of 27 articles, including 37 cases, have documented corneal adverse events that occurred following COVID-19 vaccination. The mean age was 60 ± 14.9 years (range, 27-83 years). The most common events were acute corneal graft rejection (n = 21, 56.8%), followed by herpes zoster ophthalmicus (n = 11, 29.7%) and herpes simplex keratitis (n = 2, 5.4%). The mean time from vaccination to the event was 10 ± 8.5 days (range, 1-42 days) after the first or second dose of vaccine. All patients with corneal graft rejection, immune-mediated keratolysis, and peripheral ulcerative keratitis (PUK) (n = 24, 64.9%) were managed topically with or without oral corticosteroids. Patients with herpes zoster ophthalmicus and herpes simplex keratitis were managed with oral antiviral agents. Two patients received penetrating keratoplasty due to keratolysis after invalid topical treatment. Disease resolution was noted in 29 patients (78.3%), whereas 3 (8.1%) had persistent corneal edema after graft rejection, 1 (2.7%) had corneal infiltration after HZO, and 4 (10.8%) were not mentioned in the articles. Corneal adverse events could occur after COVID-19 vaccination. After timely treatment with steroids or antiviral agents, most of the events were mild and had a good visual outcome. Administrating or increasing steroids before vaccination may be useful for the prevention of corneal graft rejection. However, the prophylactic use of antiviral treatments in patients with a herpes viral infection history is not recommend.

Steroid-Induced Ocular Hypertension in a Pediatric Patient with Acute Lymphoblastic Leukemia: A Case Report.

Glucocorticoids play a pivotal role in therapeutic protocols in acute lymphoblastic leukemia (ALL) treatment. Systemic steroids are known to be less likely to elevate the intraocular pressure when compared to topical administration, and reports addressing hypertensive ocular response in the Asian pediatric ALL population are currently limited. We report a case of a nine-year-old girl with acute lymphoblastic leukemia (ALL) who was found to have highly elevated intraocular pressure (IOP) during maintenance treatment when taking oral dexamethasone (6 mg/m2/day). Her IOP increased on day 5 after taking dexamethasone, reached a peak on day 7 or 8, and returned back to baseline on day 13 before anti-glaucoma medications were used. Thus, we prescribed IOP-lowering agents for 10 consecutive days starting on the day oral dexamethasone was administered, and observed that not only did the peak levels lower remarkably, but the IOP levels returned to baseline more rapidly as well.

Grading reliability of the tear film viscosity examination.

PURPOSE: To assess the reliability of a tear film (TF) viscosity video grading system. METHODS: Thirty-four dynamic TF viscosity videos were obtained by a clinically available TF analyzer and objectively sorted according to the movement speed of three arbitrary reflective light particles. A 4-grade system was constructed on a specially designed window for simultaneous comparison with the three standard videos. Two masked graders were invited to grade these videos under a randomized procedure. Observer reliabilities were determined by Spearman's correlation analysis and Bland-Altman agreement analysis. RESULTS: For this four-grade system, the intra-observer correlation was very strong in the two graders (ρ = 0.96 and 0.82; both P < 0.0001). However, the inter-observer correlation showed moderate strength in normal playback speed (ρ = 0.53, P = 0.002 and ρ = 0.52, P = 0.003 for 1st and 2nd gradings, respectively). In slower playback videos, the inter-observer correlation of the two graders was higher (ρ = 0.70 and P < 0.0001) when reduced to 0.8-times playback speed. Moreover, the 0.8-times mode was also significantly better than normal playback mode (P = 0.0204) in terms of inter-observer agreement. CONCLUSIONS: The dynamic 4-grade system has an excellent intra-observer reliability and a good inter-observer reliability under 0.8-times playback speed. The grading system established in this study provides a promising solution for rapidly determining the level of TF viscosity.

The severity of visual field defect and the defective angles of localized retinal nerve fiber layer using a novel approach.

BACKGROUND/PURPOSE: A modified novel analytical method for evaluating photographic retinal nerve fiber layer defect (RNFLD) was developed for the purpose of estimating the severity of early glaucomatous eyes. This new method was then compared with the original method, as described below, in relation to the visual field defect severity. METHODS: The clinical records of 47 glaucomatous eyes with qualified photographs were obtained from a prior retrospective study. The reference point of the angle was set at the center of the optic disc center (COD group) and the central vessel trunk (COV group). Angle α was the angular width between the fovea and the proximity of RNFLD, while angle ß (+c) was the sum of the angular width(s) of localized RNFLD. The correlation between the visual field parameters and the angles of RNFLD in the above two groups were analyzed. RESULTS: There were significant differences in angle α (p = 0.001) and angle ß (+c) (p = 0.016) between the two groups. Angle ß (+c) showed significant correlation with MD (p = 0.012), PSD (p = 0.035), VFI (p = 0.042) and MD (p = 0.016), PSD (p = 0.035), VFI (p = 0.031) in the COD and COV group, respectively. No correlation was found between angle α and the presence of central scotoma in both groups. CONCLUSION: Our novel method was more convenient in a clinical setting and noninferior to the original method.

A deep learning approach in diagnosing fungal keratitis based on corneal photographs.

Fungal keratitis (FK) is the most devastating and vision-threatening microbial keratitis, but clinical diagnosis a great challenge. This study aimed to develop and verify a deep learning (DL)-based corneal photograph model for diagnosing FK. Corneal photos of laboratory-confirmed microbial keratitis were consecutively collected from a single referral center. A DL framework with DenseNet architecture was used to automatically recognize FK from the photo. The diagnoses of FK via corneal photograph for comparing DL-based models were made in the Expert and NCS-Oph group through a majority decision of three non-corneal specialty ophthalmologist and three corneal specialists, respectively. The average percentage of sensitivity, specificity, positive predictive value, and negative predictive value was approximately 71, 68, 60, and 78. The sensitivity was higher than that of the NCS-Oph (52%, P < .01), whereas the specificity was lower than that of the NCS-Oph (83%, P < .01). The average accuracy of around 70% was comparable with that of the NCS-Oph. Therefore, the sensitive DL-based diagnostic model is a promising tool for improving first-line medical care at rural area in early identification of FK.

Determination of Tear Lipid Film Thickness Based on a Reflected Placido Disk Tear Film Analyzer.

This study aims at determining the thickness of the tear lipid layer (LL) observed from a placido-disc-based tear film analyzer. We prospectively collected reflections of placido-disk LL images using a tear film analyzer (Keratograph® 5M, Oculus) from subjects with dry eye symptoms. The LL thickness (LLT) over the inferior half of the cornea was estimated with the use of interference color analysis and the preprocessing of images with and without ring segmentation were obtained and analyzed. Moreover, LLTs before and after 1 h of applying topical ointment (Duratears, Alcon) were compared to validate the estimation of LLT. Our results suggested that the tear LLT can be assessed using a placido-disk-based tear film analyzer and interference color analysis. We verified a high correlation between non-segmented and segmented LL images and estimated LLT increase after applying ointment. In addition, we concluded that LLT can be evaluated by direct interference analysis without segmentation preprocessing.

Defective angles of localized retinal nerve fiber layer reflect the severity of visual field defect- a cross-sectional analysis.

BACKGROUND: In order to detect glaucomatous optic nerve damages early on and evaluate the severity of glaucoma, a previously developed analytic method based on photographic retinal nerve fiber layer (RNFL) angle defect was proposed. However, the correlation between these defective angles and the severity of visual field defect has not been verified. This study aimed to confirm the correlation described above. METHODS: We reviewed a total of 227 glaucomatous eyes (38 enrolled, 189 excluded) during an interval of 5 years. The angles of all eyes were measured on RNFL photograph, of which angle α is the angular width between the macula center and the proximity of RNFL defect, and angle ß (+c) is the sum of angular width(s) of localized RNFL defect. The severity of visual field defect was determined by mean deviation (MD), pattern standard deviation (PSD), and visual field index (VFI). Correlation analysis was performed on angle α and angle ß (+c) with the presence of central scotoma and visual field defect parameters, respectively. RESULTS: Angle ß (+c) showed significant correlation with MD (P = 0.007), PSD (P = 0.02), VFI (P = 0.03), and average RNFL thickness (P = 0.03). No correlation was found between angle α and the presence of central scotoma. CONCLUSIONS: In conclusion, measuring the angular width of localized RNFL defect is a viable method for determining the severity of visual field defect.

Tracking the Reflective Light Particles Spreading on the Cornea: An Emerging Assessment for Tear Film Homeostasis.

PURPOSE: To implement an emerging noninvasive approach for assessing the dynamic tear film (TF) homeostasis. METHODS: The video records of dynamic TF from 12 healthy orthokeratology lens wearers were obtained by a clinically available TF analyzer and decomposed as image sequences. The trajectories of TF particles were analyzed by two tracking models, the full-span model (FSM) and the fixed-duration model (FDM). FSM tracked a particle for a complete opening blink cycle, while FDM tracked 1 second of the same cycle. A power-law fitting operation [Formula: see text] was used to extract homeostasis markers based on the tracking model for each subject. RESULTS: Comparing two tracking models (N = 6), only one subject had statistical difference in averaged momentary moving speed (MMS; P = 0.0488), while none had significant difference in averaged momentary moving direction (MMD). However, both models showed good correlations in average MMS (ρ = 0.94, P = 0.0048) and MMD (ρ = 1.00, P < 0.0001) and all extracted homeostasis markers [α, ß, MMS(0.1), and MMS(2.0)]. Assessing interblink reliability in these markers under FDM tracking (N = 12), only one subject in the MMS (0.1) and another subject in the MMS (2.0) were outside 95% limits of agreement, respectively. CONCLUSIONS: FDM is a good alternative to FSM and has tracking properties of higher efficiency and easier implementation. The homeostasis markers under FDM tracking showed a good interblink consistence; therefore this approach will be a promising method for analyzing dynamic TF homeostasis in future practice. TRANSLATIONAL RELEVANCE: FDM analytical architecture can practice the past experimental platform on a TF analyzer to obtain homeostasis markers of TF.