Evaluation of Antiglaucomatous Drops on Conjunctival Thickness in Patients with Primary Open-Angle Glaucoma

A machine learning approach to predict the glaucoma filtration surgery outcome

This study aimed at predicting the filtration surgery (FS) outcome using a machine learning (ML) approach. 102 glaucomatous patients undergoing FS were enrolled and underwent ocular surface clinical tests (OSCTs), determination of surgical site-related biometric parameters (SSPs) and conjunctival vascularization. Break-up-time, Schirmer test I, corneal fluorescein staining, Meibomian gland expressibility; conjunctival hyperemia, upper bulbar conjunctiva area of exposure, limbus to superior eyelid distance; and conjunctival epithelial and stromal (CET, CST) thickness and reflectivity (ECR, SCR) at AS-OCT were considered. Successful FS required a 30% baseline intraocular pressure reduction, with values ≤ 18 mmHg with or without medications. The classification tree (CT) was the ML algorithm used to analyze data. At the twelfth month, FS was successful in 60.8% of cases, whereas failed in 39.2%. At the variable importance ranking, CST and SCR were the predictors with the greater relative importance to the CART tree construction, followed by age. CET and ECR showed less relative importance, whereas OSCTs and SSPs were not important features. Within the CT, CST turned out the most important variable for discriminating success from failure, followed by SCR and age, with cut-off values of 75 µm, 169 on gray scale, and 62 years, respectively. The ROC curve for the classifier showed an AUC of 0.784 (0.692-0.860). In this ML approach, CT analysis found that conjunctival stroma thickness and reflectivity, along with age, can predict the FS outcome with good accuracy. A pre-operative thick and hyper-reflective stroma, and a younger age increase the risk of FS failure.

Effects of Topical Antiglaucomatous Medications on Conjunctival Thickness: A Prospective Anterior Segment Optical Coherence Tomography Study

Purpose: Our aim was to evaluate the effects of topical antiglaucomatous medications on conjunctival thickness using anterior segment optical coherence tomography (AS-OCT). Methods: Thirty eyes of 30 patients with primary open angle glaucoma, who had never used any antiglaucomatous medications, enrolled in this prospective study. Followed by a full ophthalmologic examination, the conjunctival thickness was measured before treatment and at 1, 3, and 6-month post-treatment by AS-OCT. Measurements were taken from the superior bulbar conjunctiva, 3-4 mm from the limbus. Results: The mean age of patients was 67.7 ± 8.6; fourteen cases (46.7%) were given latanoprost, 2 cases (6.7%) brinzolamide+timolol, 2 cases (6.7%) betaxolol, 4 cases (13.3%) travoprost, and 8 cases (26.7%) brimonidine. The mean baseline conjunctival thickness was 222.9 ± 38 μm, while the mean conjunctival thickness was 212.8 ± 36.0 μm in the first month, 198.2 ± 35.8 μm in the third month, and 187.5 ± 40.2 μm in the sixth month. Decrease in conjunctival thickness at each examination was statistically significantly compared to baseline. (P < 0.05) Decrease in conjunctival thickness in Latanoprost subgroup was statistically significant, whereas the decreases in other active ingredients were not. Conclusions: Topical antiglaucomatous medications especially prostaglandin analogs may affect conjunctival thickness even during the first few months. This thinning effect may be crucial for the conjunctiva, as the basis of the possible filtration surgery.

Do topical ocular antihypertensives affect Dacryocystorhinostomy outcomes: The Coventry experience

BACKGROUND

It has been suggested that ocular antihypertensives are associated with an increased risk of nasolacrimal duct obstruction. This study aims to assess the effect of topical antihypertensive treatment on surgical outcomes for patients undergoing Dacryocystorhinostomy (DCR) with intubation.

METHODS

Single centre, retrospective analysis of 170 operations carried out on 144 patients between January 2014 and January 2019. Statistical analysis of DCR failure rates comparing patients on topical ocular antihypertensive treatment and those not on any topical ocular antihypertensive treatment was carried out following medical case record analysis.

RESULTS

6.9% of patients undergoing DCR surgery were on topical antihypertensive treatment. The overall failure rate for all DCR operations during this time period was 11.2%. There was a statistically significant higher rate of primary DCR failure in patients on antihypertensive treatment (p = 0.02), with the endonasal DCRs worse affected (p = 0.01). The most commonly used topical treatments were carbonic anhydrase inhibitors (CAI, 81.8%), followed by beta-blockers (72.7%). All patients who had failure of primary DCR were using topical beta-blockers and CAI at the time of surgery and post-operatively. There was no statistically significant association between failure rates and the use of preserved or unpreserved drops (p = 1.0) CONCLUSIONS: Topical ocular antihypertensive treatment may lead to a higher failure rate for DCR surgery due to the provocation of an inflammatory cicatricial response. Beta-blockers and CAIs appear to have the strongest association. Considering a primary external approach in this group as well as switching the class of topical antihypertensive treatment pre-operatively could perhaps improve DCR outcomes.

Do We Conform with European Glaucoma Society Guidelines in the Medical Treatment of Primary Open-Angle Glaucoma/Ocular Hypertension? Data from a Real-Life Practice

Purpose: To evaluate the prescribing habits of glaucoma specialists and of general ophthalmologists, and reveal the conformance with European Glaucoma Society (EGS) guidelines in the medical treatment of primary open-angle glaucoma (POAG) and ocular hypertension (OHT). Methods: Patients receiving medical treatment for POAG/OHT in the glaucoma clinic comprised the "naive group." Patients having a diagnosis and a treatment for POAG/OHT initiated in another center before presentation comprised the second group and were named as "treatment initiated elsewhere" (TIEW). All patients were retrospectively evaluated from the patients' charts. The outcome measures included the percentage of eyes treated with monotherapy, the molecule groups preferred, and the change in prescription trends over the years in both groups. Results: Seventy-two subjects were included in the naive group and 135 subjects in TIEW group. The rate of monotherapy was 76% and 36% in both groups, respectively. The molecule number was significantly higher in the TIEW group compared with naive group (1.98 ± 0.89 vs. 1.28 ± 0.56, P < 0.001). Until 2003, beta blockers, and in the 2003-2008 period, prostaglandin analogs (PGAs) were the mostly prescribed drugs in glaucoma clinic. From 2009, the rate of PGAs declined, with PGAs being replaced by combination drugs and alfa-2 agonists. Conclusions: Overtreatment rate was high among patients receiving a diagnosis and a treatment by general ophthalmologists, whereas glaucoma specialists were found to conform with EGS guidelines. A shift toward polypharmacy was observed from 2000 to 2017. The common guidelines to evaluate and treat glaucoma need to be adopted by the general ophthalmologists in their real-life practice.

Conjunctival thickness as a predictive imaging biomarker for the glaucoma filtration surgery outcome: An optical coherence tomography study

IMPORTANCE

To analyse the preoperative conjunctival thickness in glaucomatous patients undergoing filtration surgery (FS), using optical coherence tomography (OCT).

BACKGROUND

The conjunctival status represents one of the most critical determinants of the FS outcome.

DESIGN

Retrospective study.

PARTICIPANTS

Sixty-seven patients candidate to FS for uncontrolled glaucoma were enrolled.

METHODS

OCT was performed at the superior bulbar conjunctiva before FS, and at bleb site at the last follow-up (LF-up) after surgery.

MAIN OUTCOME MEASURES

Preoperative full, epithelial, and stromal conjunctival thickness (FCT, CET, CST) and reflectivity (CR), and LF-up bleb-wall thickness (BT), reflectivity (BR) and intraocular pressure (IOP), were the major outcomes. The relations between preoperative parameters and LF-up-IOP, BT and BR were calculated.

RESULTS

FS was completely successful in 23 patients (group 1), successful with medications in 22 (group 2), and failed in 22 (group 3). FCT, CET and CST were lower, whereas CR higher, in group 3 compared to groups 1 and 2 (P < .05); BT was lower (P < .001), whereas BR higher (P < .05) in group 3 compared to group 1. FCT and CST were predictors of FS outcome with lower thickness associated with increased odds of failure (odds ratio 0.922, P = .08; 0.941, P = .025). LF-up-IOP inversely correlated with FCT and CST (r = -0.447, P = .003; r = -0.408, P = .007), whereas positively correlated with CR (r = 0.789, P < .001).

CONCLUSIONS AND RELEVANCE

Preoperative conjunctival thickness and reflectivity show significant correlations with the FS outcome, both in terms of IOP and bleb-wall features. Therefore, they may be proposed as predictive imaging biomarkers to estimate the risk of filtration failure.

Anatomical and physiological considerations in scleral lens wear: Conjunctiva and sclera

While scleral lenses have been fitted using diagnostic lenses or impression moulding techniques for over a century, recent advances in anterior segment imaging such as optical coherence tomography and corneo-scleral profilometry have significantly improved the current understanding of the anatomy of the anterior eye including the morphometry of the conjunctiva, sclera, and corneo-scleral junction, as well as the ocular surface shape and elevation. These technological advances in ocular imaging along with continual improvements and innovations in scleral lens design and manufacturing have led to a global increase in scleral lens prescribing. This review provides a comprehensive overview of the conjunctiva and sclera in the context of modern scleral lens practice, including anatomical variations in healthy and diseased eyes, the physiological impact of scleral lens wear, potential fitting challenges, and current approaches to lens modifications in order to minimise lens-induced complications and adverse ocular effects. Specific topics requiring further research are also discussed.