The Effect of Pseudoexfoliation and Pseudoexfoliation Induced Dry Eye on Central Corneal Thickness

Ocular Surface Disease Signs and Symptoms in Patients with Pseudoexfoliative Glaucoma: A Case—Control Study

Purpose: The present study evaluates the differences in the prevalence of the signs and symptoms of ocular surface disease (OSD) in patients with PEX glaucoma (PEXG), compared to other glaucoma types (non-PEXG). Methods: Patients with non-PEXG and PEXG were prospectively examined for the presence and severity of OSD signs and questioned for symptoms using the OSDI (ocular surface disease index) questionnaire. Results: 116 patients were prospectively enrolled (58 non-PEXG and 58 PEXG). PEXG subjects who were older, had lower central corneal thickness (CCT) values, at a more advanced glaucoma stage and required more IOP lowering drops. OSD signs were prevalent in both groups: conjunctival hyperemia (74.5% non-PEXG vs. 94.8% PEXG), eyelid redness (70.7% vs. 96.6%), conjunctival (74.1% vs. 93.1%) and corneal fluorescein staining (81% vs. 93.1%) and abnormal TFBUT (82.8% vs. 87.9%). When adjusted for potential confounders, (older age, thinner CCT, more advanced glaucoma in PEXG) eyelid redness remained the only parameter significantly associated with PEXG, being 11 times more likely to occur in this group (p = 0.037). Conclusion: Subjects with PEXG presented a higher frequency of signs of OSD compared to other glaucoma types. When accounting for confounding factors, the only difference between the groups was the significantly higher presence (11 times more likely) of eyelid redness in PEXG, suggesting, in addition to glaucoma treatment, the impact of PEX on ocular surface integrity.

THE EFFECT OF PRIMARY ARGON LASER TRABECULOPLASTY ON INTRAOCULAR PRESSURE REDUCTION AND QUALITY OF LIFE IN PATIENTS WITH PSEUDOEXFOLIATION GLAUCOMA

The aim of the study was to assess the impact of primary argon laser trabeculoplasty (ALT) on intraocular pressure (IOP) lowering and quality of life improvement in patients with pseudoexfoliative glaucoma. Sixty patients with newly diagnosed pseudoexfoliative glaucoma who underwent primary ALT (group 2) or medication therapy (group 1) were followed-up. The effect of ALT on IOP reduction, dry eye development and number of antiglaucoma drugs used was examined. Patients were examined at the beginning of the study and then after 6, 12, and 18 months. A statistically significant difference between IOP values was observed throughout the 18-month follow-up, with the highest significance recorded 6 months after ALT (p=0.009). Twelve months after the start of the study, the TBUT value was 6.0±0.8 s in group 1 and 8.4±0.7 s in group 2. In group 2, the value of Schirmer test was constantly above 10 millimeters. The number of antiglaucoma medications used in group 1 was statistically significantly higher as compared to group 2 throughout the 18-month study period. ALT was found to be better choice for temporary regulation of IOP in patients with pseudoexfoliative glaucoma.

A Case-Cohort Study of Exfoliation Risk Factors and Literature Review

The purpose of the study is to evaluate the risk factors associated with exfoliation in a case-cohort setting and literature review. This single-center, prospective, case-cohort study was carried out from January 2010 to April 2020 on patients operated for cataract surgery by a single surgeon in Lebanon. Forty-nine consecutive patients with exfoliation syndrome (XFS) and 62 consecutive control patients were identified and further investigated for selected systemic (diabetes mellitus, systemic hypertension, asthma, or atopy) and ocular variables (baseline vision, severity of nuclear sclerosis, glaucoma, eye rubbing, history of dry eye, or allergic eye disease). The mean baseline Snellen visual acuity was 20/283 in XFS versus 20/145 in control cases (P = 0.012). XFS also demonstrated significantly denser nuclear sclerosis than controls (P = 0.00958). By univariate analysis, allergic conjunctivitis (15 [30.6%] vs. 2 [3.2%]; P < 0.001), dry eye (20 [40.8%] vs. 13 [21.0%]; P = 0.0133), and habitual rubbing of the eyes (33 [67.3%] vs. 19 [30.6%]; P < 0.001) were associated with the presence of XFS. Habitual ocular rubbing was closely associated with allergic conjunctivitis (odds ratio [OR] = 13.0; 95% confidence interval [CI]: 2.8–58.8; P = 0.032). After multivariable analysis, the following variables showed significant results: glaucoma (OR = 34.5; 95% CI: 4.4–250; P = 0.010), duration of surgery (OR = 5.6; 95% CI 2.43–12.9; P < 0.001), and habitual ocular rubbing (OR = 4.42; 95% CI: 1.97–9.90; P = 0.029). This study shows a novel potential correlation between eye rubbing and XFS in a Lebanese cohort. Chronic eye rubbing induces or may exacerbate preexistent zonular damage in subjects with XFS, hence the need to better manage concurrent ocular surface disorder in these patients.

Morphological features of the corneal endothelium in patients with pseudoexfoliative glaucoma

Purpose. To study the main morphological features of the corneal endothelium in patients with pseudoexfoliative glaucoma (PEG). Methods. We included 193 subjects aged from 55 to 75 years. The main study group (PEG) included 96 patients (192 eyes), the primary open angle glaucoma (POAG) group included 36 patients (72 eyes) with POAG, the PEX group included 31 patients (62 eyes) with pseudoexfoliation syndrome without glaucoma. The control group consisted of 30 healthy subjects (60 eyes). Main corneal endothelium parameters were evaluated using a non-contact endothelial microscope EM-935 (Haag Streit, Switzerland). Data were analyzed by STATISTICA 9 software for Windows. Results. The patients with PEG had lower endothelial cell density (ECD) in comparison to the control group (p < 0.01), and PEX group (p < 0.05). The polymegatism level in patients with PEG and POAG was higher than in the control group (p < 0.001, and p < 0.01, correspondingly). In patients with moderate and advanced PEG, the ECD was significantly lower (p < 0.01), and the polymegatism level was significantly higher (p < 0.01) than the same parameters in patients with early PEG. The lowest ECD and the highest polymegatism percentage were observed in PEG patients with more pronounced PEX manifestations, p < 0.05. No effect of IOP-lowering eye drops on the corneal endothelium parameters was revealed, p < 0.05. Conclusions. Significant morphological changes of the corneal endothelium (decreased endothelial cell density, increased polymegatism percentage) were revealed in patients with PEG. It was established that the severity of these changes is associated with the PEG and PEX severity. No effect of IOP-lowering eye drops on the corneal endothelium parameters was detected.

Pseudoexfoliative glaucoma and molecular genetic characteristics of vitamin D metabolism

Purpose. To study the possible association of 25-hydroxyvitamin D level, and vitamin D receptor (VDR) gene polymorphisms (BsmI, ApaI, TaqI, FokI) with pseudoexfoliative glaucoma (PEG) clinical manifestations. Methods. We examined 160 subjects (72 males (45%), and 88 females (55%)) aged from 55 to 75 years, residents of St. Petersburg and Leningrad region. 122 patients with PEG were enrolled in the main study group, the control group comprised 38 subjects without PEG, primary open angle glaucoma (POUG) and pseudoexfoliation syndrome (PES). 25(OH)D serum levels were assessed by chemiluminescent immunoassay (CLIA) method. Detection of VDR gene allele polymorphisms (ApaI, BsmI, FokI, and TaqI) was carried out using polymerase chain reaction – restriction fragment length polymorphism (PCR-RFLP) technique. Results. Patients with PEG had lower 25(OH)D serum levels compared to patients in the control group (39.3 ± 1.2 and 52.7 ± 2.1 nMol/l, respectively, p < 0.01). The prevalence of vitamin D deficiency was found to be higher among PEG patients than among healthy subjects (86.4% and 59.5%, respectively, p < 0.01). The prevalence of b allele (p < 0.001) and bb genotype (p < 0.001) (BsmI polymorphism), as well as of f allele and ff genotype (p < 0.05) (FokI polymorphism) in PEG patients were higher compared to healthy subjects. We found that the Fallele carriers (FokI polymorphism) had greater corneal thickness than the ff genotype carriers (547.3 ± 4.1 μm and 502.1 ± 25.8 μm, respectively, p < 0.01). It was revealed, that bb genotype, Bb genotype (BsmI polymorphism), and ff genotype (FokI polymorphism) were associated with the increased risk of PEG (OR = 8.2, CI 95%: 3.4-19.9; OR = 3.9, CI 95%: 1.7-9.0; OR = 2.3, CI 95%: 1.2-4.5, respectively). Conclusions. Results of this study for the first time ever showed the association between BsmI and FokI VDR gene polymorphisms and pseudoexfoliative glaucoma.

Conjunctival changes in different clinical variants of early pseudoexfoliation

PURPOSE

To evaluate the conjunctival signs in different forms of pseudoexfoliation (PXF) syndrome to identify signs predicting early forms of the disease.

METHODS

This observational study included patients with newly diagnosed PXF screened in the outpatient department of glaucoma services. Slit lamp photographs were captured in low and high magnification after full dilatation, and details like melanotic pigmentation, vascularity and tortuosity of vessels, scarring if any, presence of pterygium and actinic changes along with basal Schirmer's test were analysed. Variables in each subtype of PXF previously described by us, namely radial pigmentary (group A), combined pigmentary and classical (group B) and classical PXF (group C), were analysed and compared to age-matched controls. The differences between manifest (group B + C) and unmanifest or early form (group A) were also compared.

RESULTS

A total of 89 eyes from 55 patients (M/F = 38:17, 21 unilateral, 34 bilateral, 48 group A, 10 group B and 31 group C) were compared with 40 controls. The Schirmer's test was statically lower in patients with manifest PXF (10 ± 1.4 mm) and unmanifest PXF (14 ± 0.6 mm), p < 0.001. The most frequent conjunctival finding (n = 88) in this cohort was lightly pigmented melanotic pigmentation present close to limbus without evidence of any feeder vessels or actinic changes and associated with pupillary ruff atrophy in the same quadrant. Analysing different PXF forms, there was conjunctival melanosis in one or all quadrants in all forms of PXF which was more prominent in manifest PXF, present in a mean 2 ± 1.7 quadrants in unmanifest and manifest PXF, p = 0.01.

CONCLUSION

Conjunctival melanosis with associated pupillary ruff atrophy in the same quadrant may be the earliest signs of early pseudoexfoliation.

Genetics, Diagnosis, and Monitoring of Pseudoexfoliation Glaucoma

Recent studies have shed new light on the genetic factors underlying pseudoexfoliation syndrome, growing our understanding of the role of the lysyl oxidase-like 1 (LOXL1) gene and its various polymorphisms as well as identifying new genetic associations. Recent years have brought new insight on how these genetic factors interact with other factors, including environmental, to confer risk to individuals and populations worldwide. All of these findings may hold importance to the screening, diagnosis, and monitoring of pseudoexfoliation and may also help lead to the identification of novel therapeutic targets. This review serves as an update on the recent trends and findings in pseudoexfoliation syndrome.

Differences in Central Corneal Thickness between Spectral Domain-Optical Coherence Tomography and Ultrasound Pachymetry in Patients with Dry Eye Disease

Purpose. To compare central corneal thickness (CCT) values via Spectral Domain-Optical Coherence Tomography (SD-OCT) and ultrasonic pachymetry in patients with severe dry eye disease (DED) to determine the level of agreement between these 2 methods. Methods. The paired samples t-test was used to compare CCT values in severe DED patients. Matching analysis between methods was performed using intraclass correlation coefficient (ICC). Intrasession reliability of the measurement methods was calculated via the concordance correlation coefficient (CCC), variation equivalent, and Pearson's correlation coefficient. The Bland-Altman procedure was used to graphically represent the differences between CCT values. Results. The study included 56 eyes of 24 female and 4 male patients. Mean age of the patients was 50.9 ± 11.3 years. Mean CCT via Cirrus SD-OCT was 523.82 ± 30.98 μm versus 530.050 ± 31.85 μm via ultrasonic pachymetry (paired samples t-test, P < 0.001). The Bland-Altman plot showed good agreement between the examiners. The ICC for repeatability was 0.974. The CCC between the 2 methods' CCT values was 0.973. The variation equivalent was 0.976 and Pearson's correlation coefficient was 99.3%, which also indicated high correlation between the 2 methods' measurements. Conclusions. The present findings show that in patients with severe DED Cirrus SD-OCT provides reliable intraobserver CCT values.