Pseudoexfoliation in the Reykjavik Eye Study: prevalence and related ophthalmological variables

Exfoliation syndrome and exfoliation glaucoma: Current perspectives and clinical paradigms

Exfoliation syndrome and exfoliation glaucoma comprise a unique age-related ocular aggregopathy characterized by the accumulation of protein complex aggregates in different ocular structures. Recent literature and studies have expanded our knowledge of the clinical characteristic features, phenotypical variations, and molecular pathophysiology associated with disease onset or development of glaucoma. Despite years of studies on the various epidemiological, clinical, and molecular facets of the disease, the exact mechanism of disease onset, formation of aggregates, and the events that trigger the development of glaucoma marking irreversibility in the disease remains elusive. This review elaborates on the existing and new insights that we have gained over the years and highlights gaps in the knowledge about the disease that need future exploration.

Risk factors for exfoliation glaucoma - Current evidence and perspectives

Exfoliation syndrome (XFS) and exfoliation glaucoma (XFG) represent a complex matrix of ocular age-related neurodegenerative changes. Numerous decades of research on this disease entity have highlighted the unique clinical features of ocular protein-complex aggregates, which lead to tissue dysfunction of the ocular outflow channels, leading to irreversible optic nerve damage and glaucoma. While genetic studies have reported several genes associated with XFS and XFG, numerous studies have shown their association with common systemic diseases such as ischemic heart disease, cerebrovascular accidents, and hypertension. Environmental factors are also reported to play a role in the disease pathogenesis by epigenetic control of gene expression and partly explain the difference in the prevalence rates of the disease process. Despite the identification of possible triggers for the disease onset or for the development of glaucoma, the exact mechanisms or the role of several reported risk factors in disease pathogenesis remain a mystery. This review comprehensively evaluated the several risk factors in XFS and XFG while discussing the interactive interplay between the risk factors that determine the disease onset or phenotype in XFS and XFG.

Lack of evidence for GWAS signals of exfoliation glaucoma working via monogenic loss-of-function mutation in the nearest gene

PURPOSE

Exfoliation syndrome (XFS) is a systemic disease of elastin-rich tissues involving a deposition of fibrillar exfoliative material (XFM) in the anterior chamber of the eye, which can promote glaucoma. The purpose of this study was to create mice with CRISPR/Cas9-induced variations in candidate genes identified from human genome-wide association studies (GWAS) and screen them for indices of XFS.

METHODS

Variants predicted to be deleterious were sought in the Agpat1, Cacna1a, Loxl1, Pomp, Rbms3, Sema6a, and Tlcd5 genes of C57BL/6J mice using CRISPR/Cas9-based gene editing. Strains were phenotyped by slit-lamp, SD-OCT imaging, and fundus exams at 1-5 mos of age. Smaller cohorts of 12-mos-old mice were also studied.

RESULTS

Deleterious variants were identified in six targets; Pomp was recalcitrant to targeting. Multiple alleles of some targets were isolated, yielding 12 strains. Across all genotypes and ages, 277 mice were assessed by 902 slit-lamp exams, 928 SD-OCT exams, and 358 fundus exams. Homozygosity for Agpat1 or Cacna1a mutations led to early lethality; homozygosity for Loxl1 mutations led to pelvic organ prolapse, preventing aging. Loxl1 homozygotes exhibited a conjunctival phenotype of potential relevance to XFS. Multiple other genotype-specific phenotypes were variously identified. XFM was not observed in any mice.

CONCLUSIONS

This study did not detect XFM in any of the strains. This may have been due to species-specific differences, background dependence, or insufficient aging. Alternatively, it is possible that the current candidates, selected based on proximity to GWAS signals, are not effectors acting via monogenic loss-of-function mechanisms.

Association between Diabetes and Exfoliation Syndrome

Topic

This systematic review and meta-analysis summarizes the existing evidence for the association of diabetes mellitus (DM) and exfoliation syndrome (XFS).

Clinical Relevance

Understanding and quantifying these associations may aid clinical guidelines or treatment strategies and shed light on disease pathogenesis. The role of DM in determining XFS risk may also be of interest from an individual or public health perspective.

Methods

The study protocol was preregistered on the International Prospective Register of Systematic Reviews with registration number CRD42023429771. We systematically searched PubMed and Embase from inception to June 15, 2023. Screening and full-text review were conducted by 2 independent reviewers. All observational studies reporting an age-adjusted odds ratio (OR) and 95% confidence interval (CI) for the association between DM and XFS among adults were included. Quantitative synthesis involved a random-effects meta-analysis using the DerSimonian-Laird method to generate a pooled OR. Risk of bias was evaluated using the Newcastle-Ottawa Scale.

Results

Fourteen studies (9 cross-sectional and 5 case-control) comprising 47 853 participants were included in the systematic review and meta-analysis. Random-effects meta-analysis indicated no overall association between DM and XFS (OR 0.94; 95% CI, 0.73–1.21; I 2  = 68.5%). However, subgroup analysis revealed a significant inverse association among individuals ≥ 65 years (OR 0.71; 95% CI, 0.54–0.93) versus individuals < 65 years (OR 1.22; 95% CI, 0.80–1.87; P effect modification  = 0.04). The relation between DM and XFS was also inverse in case-control studies (OR 0.75; 95% CI, 0.58–0.97) but was nonsignificant in cross-sectional studies (OR 1.17; 95% CI, 0.83–1.66; P effect modification  = 0.04). Overall risk of bias was low, with tests for publication bias showing P  ≥ 0.06.

Conclusion

This meta-analysis suggests no association between DM and XFS overall, with possible inverse associations of DM with XFS in older populations. However, given the substantial heterogeneity and borderline significance for publication bias, these findings should be interpreted with caution. Our results give insight into the unique etiology and clinical relevance of XFS while proposing the need for larger longitudinal and genetic biomarker studies.

Financial Disclosure(s)

Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Lack of Association between LOXL1 Variants and Pigment Dispersion Syndrome/Pigmentary Glaucoma: A Meta-Analysis

The phenotypic similarities between exfoliation syndrome (XFS)/exfoliation glaucoma (XFG) and pigment dispersion syndrome (PDS)/pigmentary glaucoma (PG), particularly their association with material deposition in the eye's anterior segment, have prompted investigations into genetic commonalities. This study focuses on the LOXL1 gene, conducting a comprehensive meta-analysis of three candidate gene association studies. We analyzed three single nucleotide polymorphisms (SNPs) of LOXL1: rs1048661, rs3825942, and rs2165241. Our results reveal nominal significance for the exonic SNPs rs1048661 and rs3825942 (p ≤ 0.01), but show no significant association for the intronic SNP rs2165241 (p = 0.83) with PDS/PG. There was homogeneity across study cohorts (I2 = 0), and sensitivity analyses and funnel plots confirmed a lower likelihood of bias in our findings. The lack of a statistically significant association between LOXL1 variants and PDS/PG at p < 0.05 was attributable to the insufficient statistical power of the pooled data, which ranged from 5% to 37% for the three SNPs. This study suggests no association between LOXL1 variants and PDS/PG. Further validation and exploration of XFS/XFG-associated genes in larger and more diverse cohorts would be helpful to determine the genetic correlation or distinctiveness between these conditions.

Secondary glaucoma: Toward interventions based on molecular underpinnings

Glaucoma is a heterogeneous group of progressive diseases that leads to irreversible blindness. Secondary glaucoma refers to glaucoma caused by a known underlying condition. Pseudoexfoliation and pigment dispersion syndromes are common causes of secondary glaucoma. Their respective deposits may obstruct the trabecular meshwork, leading to aqueous humor outflow resistance, ocular hypertension, and optic neuropathy. There are no disease-specific interventions available for either. Pseudoexfoliation syndrome is characterized by fibrillar deposits (pseudoexfoliative material) on anterior segment structures. Over a decade of multiomics analyses taken together with the current knowledge on pseudoexfoliative glaucoma warrant a re-think of mechanistic possibilities. We propose that the presence of nucleation centers (e.g., vitamin D binding protein), crosslinking enzymes (e.g., transglutaminase 2), aberrant extracellular matrix, flawed endocytosis, and abnormal aqueous-blood barrier contribute to the formation of proteolytically resistant pseudoexfoliative material. Pigment dispersion syndrome is characterized by abnormal iridolenticular contact that disrupts iris pigment epithelium and liberates melanin granules. Iris melanogenesis is aberrant in this condition. Cytotoxic melanogenesis intermediates leak out of melanosomes and cause iris melanocyte and pigment epithelium cell death. Targeting melanogenesis can likely decrease the risk of pigmentary glaucoma. Skin and melanoma research provides insights into potential therapeutics. We propose that specific prostanoid agonists and fenofibrates may reduce melanogenesis by inhibiting cholesterol internalization and de novo synthesis. Additionally, melatonin is a potent melanogenesis suppressor, antioxidant, and hypotensive agent, rendering it a valuable agent for pigmentary glaucoma. In pseudoexfoliative glaucoma, where environmental insults drive pseudoexfoliative material formation, melatonin's antioxidant and hypotensive properties may offer adjunct therapeutic benefits. This article is categorized under: Neurological Diseases > Molecular and Cellular Physiology.

Clinical profile and demographic distribution of pseudoexfoliation syndrome: An electronic medical record-driven big data analytics from an eye care network in India

Purpose

To describe the demographics and clinical profile of pseudoexfoliation syndrome (PXF or PES) in patients presenting to a multi-tier ophthalmology hospital network in India.

Methods

This cross-sectional hospital-based study included 3,082,727 new patients presenting between August 2010 and December 2021. Patients with a clinical diagnosis of PXF in at least one eye were included as cases. The data were collected using an electronic medical record system.

Results

Overall, 23,223 (0.75%) patients were diagnosed with PXF. The majority of the patients were male (67.08%) and had unilateral (60.96%) affliction. The most common age group at presentation was during the seventh decade of life with 9,495 (40.89%) patients. The overall prevalence was higher in patients from a lower socio-economic status (1.48%) presenting from the urban geography (0.84%) and in retired individuals (3.61%). The most common location of the PXF material was the pupillary margin (81.01%) followed by the iris (19.15%). The majority of the eyes had mild or no visual impairment (<20/70) in 12,962 (40.14%) eyes. PXF glaucoma was documented in 7,954 (24.63%) eyes. Krukenberg's spindle was found in 64 (0.20%) eyes, phacodonesis in 328 (1.02%) eyes, and lens subluxation in 299 (0.93%) eyes. Among the surgical interventions, cataract surgery was performed in 8,363 (25.9%) eyes, trabeculectomy was performed in 966 (2.99%) eyes, and a combined procedure in 822 (2.55%) eyes.

Conclusion

PXF more commonly affects males presenting during the seventh decade of life from lower socio-economic status and is predominantly unilateral. A quarter of the affected eyes are associated with glaucoma and the majority of the eyes have mild or no visual impairment.

Prevalence of Pseudoexfoliation Among Adults and Its Related Ophthalmic Variables in Southern Ethiopia: A Cross-Sectional Study

PURPOSE

A community-based study was conducted to determine the prevalence and sociodemographic factors of pseudoexfoliation syndrome among adults in Southern Ethiopia.

PATIENTS AND METHODS

A community-based cross-sectional study was conducted among subjects aged 40 years or older. Subjects underwent standardized examination, including portable slit-lamp biomicroscopy before and after pupillary dilatation, and intraocular pressure measurement using Tono-Pen. Pseudoexfoliation was diagnosed on slit-lamp examination by the presence of white dandruff-like material on the pupillary margin and/or on the anterior lens capsule of one or both eyes.

RESULTS

Among 760 participants, the prevalence of pseudoexfoliation was 12.0% (95% confidence interval: 9.7-14.3%). The mean age of pseudoexfoliation cases was 63.9 years (SD 9.96, age range 40-90 years). The prevalence increased with increasing age, with 26.9% of those 60 or older affected. Slightly higher proportion of males (12.4%) were found to have pseudoexfoliation in either of the eyes than females (11.6%) which was not statistically significant (p = 0.738). Mean IOP in subjects with pseudoexfoliation was found to be 20.65 ± 5.15 mmHg, while it was 15.0 ± 2.3 mmHg for those without pseudoexfoliation. The difference between the two populations was found to be statistically significant (P < 0.05).

CONCLUSION

The prevalence of pseudoexfoliation in eyes of people in Southern Ethiopia appears greater than that reported in other places of Africa and Asia. Pseudoexfoliation occurs at a relatively younger age in our population. Increasing age is associated with the presence of pseudoexfoliation, and pseudoexfoliation in turn is associated with higher intraocular pressure.

Considerations for Corneal Surgery With Patients in the 10th Decade of Life

PURPOSE

The purpose of this study was to report the indications, ocular and systemic comorbidities, and surgical outcomes of corneal transplantation in patients older than 90 years.

METHODS

A retrospective review was conducted to identify individuals 90 years and older who underwent corneal transplantation surgery at the Bascom Palmer Eye Institute between January 2013 and October 2020. Outcomes included best-corrected visual acuity and graft survival over time. Paired t tests were used to compare visual acuity preoperatively versus postoperatively. Graft survival was evaluated with Kaplan-Meier curves.

RESULTS

Fifty-eight eyes of 52 consecutive individuals were included. The mean age of individuals was 92 ± 2 years; 26.9% were male; and 48.1% self-identified as non-Hispanic White and 38.5% as Hispanic. Postoperative follow-up was 14.7 ± 12.1 months. Of the 58 eyes, 44.8% (26/58) underwent penetrating keratoplasty, 46.6% (27/58) Descemet stripping automated endothelial keratoplasty, and 6.9% (4/58) keratoprosthesis. All surgeries were performed under monitored local anesthesia, without major complications. Surgical indications included pseudophakic bullous keratopathy (36.2%), glaucoma-associated corneal decompensation (27.6%), Fuchs endothelial dystrophy (25.9%), and perforated corneal ulceration (19.0%). The best-corrected visual acuity improved by 0.32 (95% confidence interval 0.14-0.50; P < 0.01) as early as 1 month postoperatively, and vision gains were sustained for at least 12 months. Graft survival probability at 12 months was 88%.

CONCLUSIONS

Corneal transplantation is a safe and successful procedure in restoring the visual acuity for patients older than 90 years after careful preoperative evaluation. Further research is needed to evaluate the impact of corneal transplantation on quality of life in patients in the 10th decade of life.

Exploring association between pseudoexfoliation syndrome and ocular aging

PURPOSE

Within a population-based follow-up study, to examine the 10-year incidence of pseudoexfoliation syndrome (PEX), possible risk factors for PEX and its association with ocular aging of the cornea, lens and retina.

METHODS

The baseline examination was conducted in 2006 on a random sample of 1,033 adult participants from Kaunas city (Lithuania) population of whom 631 had ophthalmic examination data at attendance of the 10-year follow-up in 2016. Detailed examination of the anterior and posterior segment of the eye was carried out. After diagnostic mydriasis PEX was diagnosed by the presence of typical grayish-white exfoliation material on the anterior capsule surface of the lens. The participants were divided to PEX and non-PEX groups.

RESULTS

PEX prevalence increased from 9.8 to 34.2% from baseline to 10-year follow-up. Nuclear cataract was common both in the PEX group (66.7%) and in those without PEX (72.2%), but this difference did not reach statistically significantly increased risk of developing cataract in those with PEX (OR 1.2; p = 0.61). Central corneal thickness (CCT) was thinner in the PEX group (529 ± 34 μm) and in the oldest group (525 ± 36 μm) (p < 0.001). Compared to baseline, corneal curvature (CC) became flatter in both groups (7.6 ± 0.27 vs 7.7 ± 0.26 mm; p < 0.001) during the follow-up, but the difference did not reach significance between groups. Corneal astigmatism was most commonly with-the-rule in both groups (37 (50.0%) vs 148 (68.5%); p > 0.05). Age, sex and PEX had no influence on age-related macular degeneration distribution.

CONCLUSION

The prevalence of PEX increased significantly with age in our population, with those with PEX having thinner and flatter corneae, but no difference in cataract and age-related macular degeneration characteristics.

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.

Distribution of intraocular pressure in a Swedish population

BACKGROUND

Increased intraocular pressure (IOP) and pseudoexfoliation (PEX) are major risk factors for open-angle glaucoma (OAG), an age-related neurodegenerative disease of significant importance for public health. There are few studies on the distribution of IOP in populations where PEX is a common finding.

METHODS

The distribution of IOP was studied in 733 subjects 65-74 years of age, examined in a population survey in the rural district of Tierp, Sweden, 1984-86. The difference between the right and left eye and the effect of which eye was measured first were examined. Odds ratios, adjusted for age and sex, according to Mantel-Haenszel (OR_MH), were calculated to estimate predictors of increased IOP, defined as a pressure ≥20 mm Hg in either eye. The pressure was measured with Goldmann applanation tonometry. Automated perimetry was used to identify OAG.

RESULTS

The distribution of IOP was close to that of other European-derived populations. The pressure in the first measured eye was higher than in the second measured eye. Increased IOP was related to OAG and PEX, OR_MH 8.97 (95% confidence interval [CI] 3.84-20.9) and 2.40 (95% CI 1.53-3.76), respectively. An IOP ≥20 mm Hg increased the risk of having been diagnosed with diabetes (OR_MH 1.83; 95% CI 1.08-3.09).

CONCLUSION

In this study of subjects 65-74-years-old in Sweden, the distribution of IOP was close to that of other European-derived populations. Although the difference was small, the pressure in the first measured eye was higher than in the second eye. Increased IOP was strongly related to untreated OAG and PEX.

Exfoliation Syndrome in Egypt: Prevalence and Association with Cataract in a Large Cohort

INTRODUCTION

Exfoliation syndrome is an age-related disease leading to ocular and systemic complications. We aimed to evaluate the prevalence of exfoliation syndrome (XFS) in Egypt and its association with cataract as one of its comorbidities.

METHODS

In a retrospective, hospital-based study, 155,032 Egyptians aged over 40 years from all 27 Egyptian governorates were evaluated for the prevalence of XFS and cataract in the period between January 2015 and June 2020.

RESULTS

A total of 2448 (1.6%) of the studied subjects had XFS. Their mean age was 71.2 ± 9.62 years which was significantly higher than those of subjects with no XFS. Men comprised 1348 (55.1%) of those diagnosed with XFS and this association was statistically significant (OR 1.57, 95% CI 1.45-1.70). Considering the ratio between subjects in our cohort from each region and its real population, the overall corrected prevalence in Egypt was 4.49% (Territorial regions 6.89%, Upper Egypt 5.51%, Lower Egypt 4.38%, and Greater Cairo 3.29%). Among all subjects with XFS, cataract was found in 2150 subjects (87.8%) and XFS represented 6.4% of all subjects diagnosed with cataract in our cohort (n = 33,610). Among subjects with no cataract (n = 121,422), 298 subjects had XFS (OR 0.04, 95% CI 0.03-0.04).

CONCLUSION

Egypt has a moderate XFS prevalence compared to other countries. There is a strong association between XFS and cataract, and XFS was more common in elderly males. The results can be explained by differences in diet, ethnicity, climate, and maybe other factors.

Late in-the-bag intraocular lens dislocation

This review aimed to evaluate the cumulative incidence, patient characteristics, predisposing conditions, and treatment outcomes for late in-the-bag intraocular lens (IOL) dislocation. Literature searches in PubMed (MEDLINE), Embase, and Cochrane Library Central database identified 1 randomized clinical trial, 1 prospective case series, 2 prospective cohort studies, and 36 retrospective studies of this condition, which showed that the cumulative incidence was 0.5% to 3%, it occurred on average 6 to 12 years after cataract surgery, and mean patient age was 65 to 85 years. Pseudoexfoliation syndrome, myopia, and previous vitreoretinal surgery were the most common predisposing conditions. Studies indicated that IOL repositioning and IOL exchange provided similar visual outcomes and were equally safe. The long-term visual outcome seemed satisfactory. However, the quality of evidence regarding treatment was in general quite low. More studies of late in-the-bag IOL dislocation are needed, and in particular, different surgical techniques should be included in high-quality clinical trials.

Complications and visual outcomes of cataract surgery in patients with pseudoexfoliation

PURPOSE

To compare outcomes of cataract surgery performed by ophthalmic trainees and consultants in patients associated with pseudoexfoliation (PXF) METHODS: Retrospective review of medical records of all patients with PXF who had undergone cataract surgery from January 2016 to December 2018 at L V Prasad Eye Institute, Hyderabad, India, were analysed RESULTS: A total of 914 eyes were included in the study; surgeries on 501 (54.8%) eyes with PXF were performed by trainees, while 413 (45.2%) were performed by consultants. Posterior capsule rupture (PCR) with vitreous loss (VL) occurred in significantly fewer eyes operated on by consultants (n = 8, 1.9%) than those operated on by trainees (n = 23, 4.5%) (p = 0.002). Eyes that underwent small incision cataract surgery (n = 100, 21.2%) had a significantly greater number of complications than those that underwent phacoemulsification (n = 31, 7.1%) (p = 0.00001). Multivariate logistic regression analysis shows that chances of a complication are higher when operated on by a trainee (OR = 1.59, 95% CI: 1.09-2.34, p = 0.02).The mean logMAR corrected distance visual acuity of patients one month post-surgery was significantly higher for patients in the consultant group (0.15 ± 0.3) than for those in the trainee group (0.2 ± 0.4) (p = 0.003).

CONCLUSION

Patients with PXF operated on by trainees for cataract had a relatively higher risk of developing PCR with VL and had poorer visual outcomes than those operated on by consultants.

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.

Two-year efficacy after first transscleral controlled cyclophotocoagulation in patients with and without pseudoexfoliation

Purpose

Transscleral controlled cyclophotocoagulation (COCO) is a transscleral 810-nm diode laser cyclophotocoagulation that automatically adjusts the applied laser energy utilizing an optical feedback loop. The present study investigates the influence of pseudoexfoliation (PEX) on the efficacy of COCO in a Caucasian study population.

Methods

Retrospective data from 130 consecutive eyes were analyzed during a 2-year follow-up. Baseline characteristics, intraocular pressure (IOP), number of IOP-lowering medications, visual field, best-corrected visual acuity (BCVA), and secondary surgical interventions (SSI) were analyzed. The primary endpoint was IOP reduction at M24 compared to baseline, and the secondary endpoints were IOP course, reduction of IOP-lowering medications, surgical success, and IOP-lowering SSIs stratified by PEX and baseline IOP.

Results

IOP reductions of −35, −39, −25, −25, −23, −34, and −36% could be achieved from baseline to D1, W1, M1, M3, M6, M12, and M24 (all p < 0.001), respectively, while there was a significant overall reduction over time (p < 0.001) in the number of topical IOP-lowering medications postoperatively. The proportion of eyes requiring additional systemic IOP-lowering medication reduced from 31 to 0% at M24 (p = 0.025). Eyes without PEX and IOP < 30 mmHg at baseline had the lowest risk for IOP-lowering SSIs (p < 0.03). BCVA dropped at M12 (0.25 [95% CI: 0.12–0.38]), and the drop persisted during the following 12 months.

Conclusion

The present study demonstrates a midterm IOP-lowering effect after COCO while reducing the burden for topical and systemic IOP-lowering medications. Patients without PEX and IOP < 30 mmHg have a lower risk of SSI. The procedure per se cannot be excluded as causative for the decreased postoperative BCVA. Further prospective investigations are suggested.

Molecular Genetics of Glaucoma: Subtype and Ethnicity Considerations

Glaucoma, the world’s leading cause of irreversible blindness, is a complex disease, with differential presentation as well as ethnic and geographic disparities. The multifactorial nature of glaucoma complicates the study of genetics and genetic involvement in the disease process. This review synthesizes the current literature on glaucoma and genetics, as stratified by glaucoma subtype and ethnicity. Primary open-angle glaucoma (POAG) is the most common cause of glaucoma worldwide, with the only treatable risk factor (RF) being the reduction of intraocular pressure (IOP). Genes associated with elevated IOP or POAG risk include: ABCA1, AFAP1, ARHGEF12, ATXN2, CAV1, CDKN2B-AS1, FOXC1, GAS7, GMDS, SIX1/SIX6, TMCO1, and TXNRD2. However, there are variations in RF and genetic factors based on ethnic and geographic differences; it is clear that unified molecular pathways accounting for POAG pathogenesis remain uncertain, although inflammation and senescence likely play an important role. There are similar ethnic and geographic complexities in primary angle closure glaucoma (PACG), but several genes have been associated with this disorder, including MMP9, HGF, HSP70, MFRP, and eNOS. In exfoliation glaucoma (XFG), genes implicated include LOXL1, CACNA1A, POMP, TMEM136, AGPAT1, RBMS3, and SEMA6A. Despite tremendous progress, major gaps remain in resolving the genetic architecture for the various glaucoma subtypes across ancestries. Large scale carefully designed studies are required to advance understanding of genetic loci as RF in glaucoma pathophysiology and to improve diagnosis and treatment options.

Pseudoexfoliation syndrome and relating factors in a rural Japanese population: the Kumejima Study

PURPOSE

To report the prevalence of pseudoexfoliation (PEX) syndrome and glaucoma associated with PEX (PEX-G) and their relating factors of them in a south-western island of Japan.

METHODS

A population-based survey of all residents aged ≥ 40 years was conducted in Kumejima, Okinawa, Japan, and 3762 subjects (participation rate, 81.2%) underwent detailed ophthalmic examinations. Presence of PEX material on the lens capsule, iris surface and/or pupillary margin was determined by slit-lamp biomicroscopy. Glaucoma was diagnosed according to the criteria of the International Society of Geographical and Epidemiological Ophthalmology.

RESULTS

In subjects aged ≥ 40 years, prevalence rates of PEX syndrome, PEX without glaucoma and PEX-G in at least one eye were 1.5% (95% confidence interval [CI]: 1.0-1.9%), 1.3% (95% CI: 0.9-1.7%) and 0.1% (95% CI: 0.0-0.2%), respectively, excluding eyes after cataract surgery; and 2.8% (95% CI: 2.3-3.3%), 2.2% (95% CI: 1.8-2.6 %) and 0.4% (95% CI: 0.2-0.6%), respectively, including eyes after cataract surgery. Cataract surgery had been performed in 61% of subjects with PEX in at least one eye; presence of PEX showed no significant effects on the intraocular pressure (IOP). A multivariate analysis showed that PEX was associated with older age (p < 0.0001, odds ratio: 1.10 [95% CI: 1.07-1.13]) and working outdoors (p = 0.0395, odds ratio: 2.18 [95% CI: 0.99-4.82]).

CONCLUSIONS

The prevalence rates of PEX syndrome and PEX-G in a south-western island of Japan were reported. PEX showed no significant effect on IOP, and age and working outdoors were significantly related with PEX.

Association between Obstructive Sleep Apnea and Exfoliation Syndrome: The Utah Project on Exfoliation Syndrome

PURPOSE

Exfoliation syndrome (XFS), the most common recognizable cause of open-angle glaucoma worldwide, is a systemic disorder with genetic predisposition due to variations in lysyl oxidase-like 1 (LOXL1) function, leading to altered elastin matrices in ocular and systemic tissues. Obstructive sleep apnea (OSA) is a highly prevalent disorder also involving elastic tissue dysfunction and is associated with glaucoma. Because of the similarities between the disorders, we sought to uncover any relationship in the prevalence of these diagnoses.

DESIGN

Case-control, retrospective cohort study.

PARTICIPANTS

A cohort of 81 735 patients diagnosed with OSA at ages 50 to 90 years was identified from medical records from 1996 to 2017 in the Utah Population Database. Case subjects were matched to random controls on sex and birth year in a 4:1 ratio.

METHODS

International Classification of Diseases, Ninth Revision (ICD-9) codes or their Tenth Revision equivalent were used to define a diagnosis of OSA (ICD-9 327.23) and a diagnosis of XFS (ICD-9 365.52 and 366.11). Conditional logistic regression odds ratios (ORs) accounting for individual matching on sex and birth year were used to estimate the risk of XFS in patients with OSA. Models included adjustment for race, obesity, tobacco use, hypertension (HTN), atrial fibrillation (AF), and chronic obstructive pulmonary disease (COPD).

MAIN OUTCOME MEASURE

Whether patients with OSA have an increased risk of diagnosis of XFS compared with controls without OSA.

RESULTS

There was an increased risk of an XFS diagnosis in patients with OSA compared with non-OSA controls (OR, 1.27; 95% confidence interval [CI], 1.02-1.59; P = 0.03). In a stratification of patients by HTN diagnosis history, patients with OSA and HTN exhibited an increased risk of XFS compared with non-OSA controls with HTN (OR, 2.67; 95% CI, 2.06-3.46; P < 0.0001).

CONCLUSIONS

Patients with OSA may be at an increased risk of XFS compared with patients without OSA, particularly in patients with a history of HTN.

Clinical Features of Pseudoexfoliative Glaucoma in Treated Polish Patients

PURPOSE

The aim of this study was to describe clinical characteristics of glaucomatous optic neuropathy in treated Polish patients with pseudoexfoliative glaucoma.

METHODS

In the course of the study, 348 eyes of 231 patients with pseudoexfoliative glaucoma. The patients involved in the study were treated in the Department of Diagnostic and Microsurgery of Glaucoma in Lublin between 2012 and 2019. The following parameters were assessed in the examination: visual acuity, slit-lamp biomicroscopy with evaluation of anterior segment of the eye, gonioscopic examination, stereoscopic fundus examination of the eye, intraocular pressure, visual field, and pachymetry.

RESULTS

The mean age of all the patients was 73.16 years (SD±8.03). The mean age of women was 74.06 (SD±6.97), and the mean age of men was 71.8 (SD±8.51, p=0.006265). Women represented 37.93% (n=132) of the studied group, while men 62.07% (n=216). In the group of patients younger than 65 years of age, 27.9% were male and 15% female (p=0.0021). In the whole studied group, mean peak IOP was 29.25 mmHg with higher mean values in male patients (M vs F: 33.24 mmHg vs 26.86 mmHg; p=0.000). Peak values exceeding 30 mmHg were significantly more frequent in males (M vs F: 56.5% vs 31.9%; p=0.0000). Peak IOP never exceeding 21 mmHg was observed in 18.6% of the patients. The mean value of MD (Mean Deviation) was -12.85 dB in the whole group. The men were more likely to have more advanced glaucoma, according to MD (M vs F: -16.35 dB vs -11.13 dB; p=0.0000).

CONCLUSION

Pseudoexfoliative glaucoma was more frequently observed in men with younger age, higher IOP, and more advanced glaucoma. Normotensive glaucoma was observed in 18.6% of the patients with pseudoexfoliative glaucoma.

Incidence and baseline risk factors for pseudoexfoliation in Sweden: a long-term follow-up study

PURPOSE

To estimate the incidence of pseudoexfoliation (PEX) and its associated risk factors in a defined population in Sweden.

METHODS

The development of PEX was studied in a cohort of 489 residents aged 65-74 years, examined in a population survey in the municipality of Tierp 1984-1986. To expand the sample size, 576 people were recruited by means of glaucoma case records established at the Eye Department in Tierp in 1978-2007. In this way, the cohort comprised 1065 subjects, representing nearly 10 500 person-years at risk. Incidence rates with 95% confidence intervals (CIs) were calculated. Survival analyses were performed to identify predictors for PEX. Those with a follow-up time shorter than 1 year were excluded.

RESULTS

By the end of the study in November 2018, 179 new cases of PEX had been found. Of these, 78 had participated in the population survey, equal to an incidence rate of 14.8 per 1000 person-years (95% CI 11.5-18.1). The development of PEX was associated with higher age (hazard ratio 1.08 per year; 95% CI 1.03-1.13) and female gender (hazard ratio 1.59; 95% CI 1.16-2.18).

CONCLUSION

In this study on a Swedish population, the incidence of PEX was high. Increasing age and female gender were the only predictors for PEX identified.

Evaluation of the optic nerve head vessel density in the patients with asymmetric pseudoexfoliative glaucoma: an OCT angiography study

PURPOSE

To evaluate vascular microcirculation changes of the optic nerve head (ONH) in the patients with asymmetric pseudoexfoliative glaucoma (XFG) using optical coherence tomography angiography (OCTA) and to compare vessel density (VD) results with healthy individuals.

METHODS

This prospective study enrolled 120 eyes in total. The eyes were divided into 3 groups: 40 glaucomatous and 40 non-glaucomatous fellow eyes without clinically pseudoexfoliation material (XFM) of patients with asymmetric XFG, and 40 healthy eyes as controls. The optic disc region was evaluated with OCTA (Optovue, Inc., Fremont, CA). VD was assessed as the ratio of the area formed by the vessels in 3 different regions: (1) inside disc; (2) in the peripapillary area defined as a 1-mm wide elliptical annulus around the disc; and (3) in the whole image defined as a 4-mm wide papillary region.

RESULTS

There were significant decreases in VD values of all regions in XFG eyes compared to fellow and control eyes (p < 0.05 for all comparisons). The mean VD values of peripapillary area and whole image were lower in the non-glaucomatous fellow eyes compared with control eyes (p = 0.011 and p = 0.015, respectively). The receiver operating characteristic analysis for differentiating fellow eyes from healthy eyes had highest area under the curve and sensitivity at 90% specificity for superior-hemi (0.811, 65.2%), followed by ppVD (0.775, 61.8%) and whole image (0.743, 55.9%).

CONCLUSIONS

OCTA as a novel imaging may be a valuable structural test in diagnosis and follow-up of glaucoma.

Prevalence and Associated Factors of Pseudoexfoliation in a Russian Population: The Ural Eye and Medical Study

PURPOSE

To assess the prevalence of pseudoexfoliation (PEX) and its associations in a Russian population.

DESIGN

Population-based cross-sectional study.

METHODS

Setting: Ufa capital of Bashkortostan, Russia and a rural region in Bashkortostan.

PARTICIPANTS

the Ural Eye and Medical Study included 5,899 (80.5%) of 7,328 eligible individuals (mean age, 59.0 ± 10.7 years old; range, 40-94 years).

OBSERVATION PROCEDURES

as part of an ophthalmological and general examination, presence and degree of PEX was assessed using slit-lamp biomicroscopy after medical pupillary dilation.

MAIN OUTCOME MEASUREMENTS

PEX prevalence.

RESULTS

After excluding pseudophakic and aphakic individuals, the study included 5,451 (92.4%) participants. PEX prevalence (3.6%; 95% confidence interval [CI]:3.1-4.1), increased from 0.5% (95% CI, 0.1-0.9) in individuals 40 to <50 years old to 10.4% (95% CI, 5.0-15.8) in individuals aged 80+ years. Higher PEX prevalence was associated (multivariate analysis) with older age (odds ratio [OR], 1.09; 95% CI, 1.07-1.11; P < 0.001), Russian ethnicity (OR, 1.50; 95% CI, 2.09-1.11;P = 0.02), higher prevalence of open-angle glaucoma (OR, 2.40; 95% CI, 1.36-4.23;P = 0.003), and higher intraocular pressure (OR, 1.06; 95% CI, 1.02-1.09;P = 0.001). PEX prevalence was not significantly associated with gender (P = 0.49), region of habitation (P = 0.11), body mass index (P = 0.68), level of education (P = 0.26), smoking (P = 0.11), alcohol consumption (P = 0.52), history of cardiovascular or cerebrovascular disease (P = 0.94) and dementia (P = 0.77), prevalence of diabetes mellitus (P = 0.16), arterial hypertension (P = 0.45), chronic obstructive pulmonary disease (P = 0.73), chronic kidney disease (P = 0.09), and hearing loss (P = 0.31).

CONCLUSIONS

In this typical, ethnically mixed, population from Russia with an age of 40+ years, PEX prevalence (3.6%; 95% CI, 3.1-4.1) was associated with older age, Russian ethnicity, higher intraocular pressure and open-angle glaucoma. It was independent of any systemic parameter including diabetes, arterial hypertension, previous cardiovascular and cerebrovascular diseases and dementia.

Link of ocular pseudoexfoliation syndrome and vascular system changes: results from 10-year follow-up study

PURPOSE

To examine the 10-year incidence of the pseudoexfoliation syndrome (PEX) in adults in a population-based follow-up study, to determine its link with vascular diseases, and to identify possible risk factors of the PEX.

METHODS

The baseline examination was performed in 2006 on a random sample of 1033 participants from Kaunas city (Lithuania) population. In 2016, a follow-up study of 686 participants who returned for the examination was conducted. The respondents filled out a questionnaire, an ophthalmological examination was performed, and the presence of vascular diseases was determined by the anamnesis and electrocardiogram evaluation data. Binary univariate and multivariate logistic regression analyses were conducted with the PEX and vascular diseases as predictors, controlling for age. Odds ratios (OR) and 95% confidence intervals of OR were calculated for the risk of new PEX cases.

RESULTS

During 10 years, the prevalence of the PEX in the study population increased from 10.3 to 34.2%. The rates of ischemic heart disease (IHD) and IHD combined with stroke were significantly higher in the PEX subjects than in the non-PEX subjects. The risk of the PEX among persons with IHD was, on the average, by 1.5-fold higher, and among those with IHD and stroke, on the average, by 1.6-fold higher as compared to persons without the aforementioned pathologies (accordingly, p = 0.014 and p = 0.010).

CONCLUSION

The prevalence of the PEX increased significantly with age. The risk of the PEX was significantly higher among persons with IHD and even higher among persons with IHD and stroke. In the future, a greater understanding of the cardiovascular, metabolic, and environmental components associated with the PEX may lead to more specific lifestyle-related preventive strategies to decrease the disease burden.

Epidemiology of Exfoliation Syndrome

BACKGROUND

From a historical standpoint the epidemiology of exfoliation syndrome (XFS) is one of the most controversial subjects in ophthalmic literature. Current literature abounds with studies on the prevalence of XFS in various ethnic populations and clearly XFS is a common condition, but its true prevalence is difficult to ascertain. Overall, XFS is considered to be the most common identifiable cause of glaucoma worldwide.

PURPOSE

This review critically examines the published literature documenting the epidemiological features of XFS and attempts to provide a unified concept concerning existing controversy.

METHODS

A critical review of selected literature pertaining to the epidemiology of XFS.

RESULTS

It is well established that XFS and the ensuing exfoliative glaucoma have a worldwide prevalence and a progressively increasing age-related incidence. The prevalence of the condition is significantly underestimated. Many past studies have proposed clear geographic variations within and between ethnic groups. In contrast, there has also been some epidemiological evidence suggesting that the prevalence of XFS is similar within various ethnic groups. Published literature fails to address the potential role and impact of suspected exfoliation cases in the reported prevalence figures of the condition. Incidence figures for the condition are limited and vary extensively. Cumulative data have indicated that several, as yet partly understood genetic, ethnic, and environmental factors contribute to the varied prevalence of this condition.

CONCLUSIONS

Further understanding on XFS epidemiology is needed. Only a future large prospective study conducted by the same investigators, using similar methodologies for different ethnic populations will prove beyond doubt the hypothesis that significant geographic variations exist. Since patients with exfoliative glaucoma are at significant risk of losing vision it is vital to elucidate the causes and the risk of developing XFS. To reach this goal, it is important to better delineate the early changes of XFS and to focus research efforts on modifiable factors for XFS development.

Twelve-Year Incidence and Baseline Risk Factors for Pseudoexfoliation: The Thessaloniki Eye Study (An American Ophthalmological Society Thesis)

PURPOSE

To determine the 12-year incidence of pseudoexfoliation (PEX), baseline risk factors for incident PEX and risk factors for incident pseudoexfoliative glaucoma (PEXG) among those with PEX in an elderly white population.

METHODS

Longitudinal, population-based study in Thessaloniki, the major urban center in Northern Greece. The baseline cohort included 2554 participants ≥60 years old. The surviving cohort was re-examined 12 years later using the same methodology. PEX was defined as typical fibrillar material at the pupil margin and/or on the lens capsule. Glaucoma was defined as both structural and functional damage, irrespective of intraocular pressure (IOP).

RESULTS

Of 1468 eligible subjects in the surviving cohort, 1092 (74%) participated in the follow-up study. The mean age ± standard deviation (SD) at baseline was 68.9 ± 4.6 years. The mean follow-up time was 11.6 ± 1.6 years. The 12-year incidence of PEX was 19.6% (95% confidence interval (CI), 17.1-22.2), with women more likely to be affected than men (Fisher's exact test, P = .0197). Higher axial length was associated with lower odds of incident PEX (odds ratio [OR], 0.72 per mm; 95% CI, 0.57-0.92). PEX at baseline was not associated with an increased likelihood of major vascular disease (P = .9038). Higher baseline IOP (OR, 1.26 per mm Hg; 95% CI, 1.07-1.48) and history of heart attack at baseline (OR, 13.49; 95% CI, 2.85-63.87) were associated with a greater likelihood of developing PEXG among those with PEX. A history of alcohol consumption at baseline was protective of individuals developing PEXG if they had PEX at baseline.

CONCLUSION

This is one of the very few longitudinal population-based studies that has specifically assessed the incidence of PEX. The association with axial length was previously found only in a cross-sectional study. The associations with heart attack and alcohol consumption are new findings. In individuals with baseline PEX, higher IOP at baseline, history of heart attack at baseline, and no alcohol consumption were associated with a greater likelihood of developing glaucomatous damage approximately 12 years later. NOTE: Publication of this article is sponsored by the American Ophthalmological Society.

Frequency and surgical difficulties associated with pseudoexfoliation syndrome among Indian rural population scheduled for cataract surgery: Hospital-based data

Purpose:

To study the frequency and intraoperative difficulties associated with pseudoexfoliation (PXF) syndrome at a tertiary eye care center in a rural central India.

Methods:

This study included patients scheduled for cataract surgery who were diagnosed with PXF syndrome. All patients underwent a complete ophthalmologic evaluation, including slit-lamp examination, tonometry, gonioscopy, and ophthalmoscopy before the surgery. Cataract surgeries were performed by a single surgeon who reported the intraoperative difficulties.

Results:

In total, 1022 phakic eyes of 1823 patients were evaluated, 226 of whom (22.1%) were diagnosed with PXF syndrome. Most eyes (n = 81, 35.8%) with PXF syndrome were ≥81 years old. Eighty-six eyes (38.1%) had bilateral involvement, whereas 70 (30.9%) had right or left eye involvement. Further, PXF material was distributed on the iris, pupil, and lens in 70 eyes (30.9%) and on the pupillary margin in 36 eyes (15.9%). The mean pupillary dilation was 5.1 (±1.4) mm in patients with PXF syndrome compared with 7.2 (±1.6) mm in those without it (P = 0.03). Grade VI cataract was observed in 93 eyes (41.2%) and hypermature cataract was the most commonly observed cataract stage. Twenty-one eyes (9.3%) had increased intraocular pressure. Intraoperative difficulties were encountered in 62 eyes (27.4%) with poor pupillary dilation being the most common problem (32 eyes, 14.2%), followed by zonular dehiscence (18 eyes, 8%).

Conclusion:

This hospital-based study showed that PXF syndrome is common in Indian rural population and that the intraoperative complication rate in these patients is high.

Descemet's membrane endothelial keratoplasty for pseudoexfoliation syndrome: a case series

Background

To evaluate the clinical outcomes and features of Descemet’s membrane endothelial keratoplasty (DMEK) for eyes with pseudoexfoliation syndrome (PEX).

Methods

In this retrospective study, 37 DMEK cases were reviewed from available medical records. Patients who exhibited endothelial dysfunction derived from PEX or Fuchs endothelial corneal dystrophy (FECD) and successfully underwent cataract surgery about four weeks before DMEK were enrolled. The best spectacle-corrected visual acuity (BSCVA), central corneal thickness (CCT), endothelial cell density (ECD), and incidence of intra-operative/post-operative complications of DMEK were analyzed.

Results

This study included 14 eyes of 14 patients (PEX: n = 6, FECD: n = 8). There was no primary graft failure. In the PEX group, BSCVA improved from 0.67 ± 0.28 at the preoperative point to 0.43 ± 0.14 at 1 month, 0.27 ± 0.10 at 3 months, and 0.19 ± 0.08 at 6 months after DMEK. The donor corneal ECD was 2704 ± 225 cells/mm² at the preoperative point and decreased to 1691 ± 498 cells/mm² at 1 month, 1425 ± 366 cells/mm² at 3 months, and 1281 ± 340 cells/mm² (52.7 ± 11.7% less than ECD of the donor graft) at 6 months after DMEK. None of the patients required rebubbling. When compared with the FECD group, no statistical difference was observed in CCT (p = 0.821); BSCVA (p = 0.001) and the reduction rate of ECD (p = 0.010) were relatively worse.

Conclusions

DMEK is effective for the treatment of endothelial dysfunction due to PEX.

Electronic supplementary material

The online version of this article (10.1186/s12886-019-1130-1) contains supplementary material, which is available to authorized users.

SPECIFIC CHARACTERISTICS OF OCULAR BIOMETRIC FACTORS IN GLAUCOMATOUS PATIENTS WITH PSEUDOEXFOLIATIVE SYNDROME AS MEASURED BY OPTICAL LOW-COHERENCE REFLECTOMETRY

The aim of the study was to assess biometric factor aberrations and differences among groups of eyes with cataract and pseudoexfoliative syndrome, cataract and pseudoexfoliative glaucoma, and cataract and primary open-angle glaucoma (POAG), and to determine biometric factors of the eye specific for the group of glaucomatous patients with pseudoexfoliative syndrome by use of optical low-coherence reflectometry. This retrospective study included 72 patients, and the study sample of 102 eyes was divided into the following three groups according to diagnosis: 29 eyes with pseudoexfoliative syndrome and cataract; 36 eyes with POAG and cataract; and 37 eyes with pseudoexfoliative glaucoma and cataract. Data on biometric measurements (central corneal thickness, pupillary diameter, anterior chamber depth, lens thickness, axial length, retinal thickness, astigmatism and white-to-white) obtained by use of optical low-coherence reflectometry on a Lenstar LS 900® (Haag-Streit International) were collected and analyzed by thorough survey of medical documentation of patients scheduled for cataract surgery at Department of Ophthalmology, Sveti Duh University Hospital in Zagreb, Croatia. Comparative analysis of the groups yielded statistically significant differences in central corneal thickness (F2/99=7.066; p=0.001) and lens thickness (F2/96=5.133; p=0.008). The group of eyes diagnosed with pseudoexfoliative glaucoma and cataract had a significantly thinner cornea as compared with the other two groups and a significantly thicker lens as compared with the group of eyes with POAG and cataract. In conclusion, optical low-coherence reflectometry revealed differences in biometric factors among the three groups of eyes, with a statistically significantly thinner cornea and thicker lens in the group of glaucomatous patients with pseudoexfoliative syndrome.

Monitoring and management of the patient with pseudoexfoliation syndrome: current perspectives

Pseudoexfoliation syndrome (PES) is a complex and age-related systemic disorder characterized by the progressive accumulation and granular deposition of pseudoexfoliative material in various intraocular and extraocular tissues. The diagnosis of PES is so important because it is a major risk factor for complications during cataract surgery and the most frequent cause of secondary glaucoma. In addition to ocular complications, PES is related with numerous systemic abnormalities, for which the list is growing steadily. Therefore, management and monitoring of patients with PES are crucial. The aim of this paper was to review current perspectives on monitoring patients with PES and addressing management of ocular and systemic associations of this clinically important and biologically fascinating disease.

The clinical features in patients with newly diagnosed pseudoexfoliative glaucoma in Serbia

PURPOSE

To evaluate the clinical characteristics of newly diagnosed pseudoexfoliative glaucoma and compare them with those pertaining to newly diagnosed primary open-angle glaucoma as well as pseudoexfoliation syndrome.

METHODS

This case-control study involved 306 participants, including patients with newly diagnosed pseudoexfoliative glaucoma, age- and sex-matched normal controls, patients with newly diagnosed primary open-angle glaucoma, and subjects with pseudoexfoliation syndrome. The study was conducted at the Glaucoma Department of Clinic for Eye Diseases, Clinical Center of Serbia, as the referral center for glaucoma in Serbia.

RESULTS

The mean age in the pseudoexfoliative glaucoma, primary open-angle glaucoma, pseudoexfoliation syndrome, and normal control groups was 73.61 ± 8.46, 65.50 ± 8.97, 74.81 ± 6.80, and 73.58 ± 9.34 years, respectively (pseudoexfoliative glaucoma vs primary open-angle glaucoma, p < 0.001). Unilateral pseudoexfoliative glaucoma was diagnosed in 35 patients (42.2%). The intraocular pressure was higher in the eyes affected by pseudoexfoliative glaucoma (32.0 ± 9.5 mmHg) than that in the primary open-angle glaucoma eyes (28.8 ± 5.9 mmHg) (p < 0.001). In pseudoexfoliative glaucoma and primary open-angle glaucoma eyes, glaucoma severity was determined via the vertical cup-to-disk ratio (C/D) 0.65 (0.45-1.0) versus 0.60 (0.45-1.0), p = 0.048 and visual field mean deviation -5.68 (-1.58 to -30.9) versus -4.70 (-1.39 to -31.0), p = 0.045. Alzheimer's was the only systemic disease associated with pseudoexfoliative glaucoma in the study sample, with an odds ratio of 0.021 (95% confidence interval = 0.00-21.52, p = 0.022).

CONCLUSION

At the time of diagnosis, pseudoexfoliative glaucoma exhibits different clinical features compared with primary open-angle glaucoma. Higher intraocular pressure, narrow or occludable angle, increased trabecular pigmentation, phacodonesis, and poorer pupillary dilatation emerged as the factors associated with pseudoexfoliative glaucoma.

The Association of Serum Vitamin D Levels with Pseudoexfoliation Glaucoma/Syndrome

Results:

PEX glaucoma group consisted of 17 males and 14 females, PEX syndrome group of 27 males and 7 females, and the control group of 27 males and 16 females. The mean age was 70.9±8.9 years, 72.1±7.3 years, and 67.9±9.1 years in PEX glaucoma, syndrome and control group, respectively. Mean vitamin D levels were 9.4±7.7 ng/mL, 7.9±6,1 ng/mL, 11.5±14.2 ng/mL in PEX glaucoma, syndrome and control group, respectively (p>0.05). The mean serum vitamin D level was 8.04±4.7 ng/mL in those who underwent glaucoma surgery and 10.1±8.7 ng/mL in those who didn't undergo glaucoma surgery in PEX glaucoma group (p>0.05). No difference was found between the PEX glaucoma subgroups in terms of the mean deviation when classified according to vitamin D levels (<10 ng/mL, ≥10 ng/mL) (p>0.05).

Conclusion:

Although we found no statistically significant difference between the PEX syndrome/ glaucoma, and control group in terms of serum vitamin D levels, serum vitamin D levels were lower in PEX syndrome and glaucoma group than control group. Our results indicate that serum vitamin D levels have no effect on the development of PEX glaucoma/syndrome or the control of the disorder in cases with PEX glaucoma. However, these results need to be supported with further studies on a larger number of patients and with longer follow-up.

What have we learned about exfoliation syndrome since its discovery by John Lindberg 100 years ago?

Exfoliation syndrome (XFS) is a systemic disease with significant ocular manifestations, including glaucoma and cataract. The disease impacts close to 70 million people globally and is now recognised as the most common identifiable cause of open-angle glaucoma. Since the discovery of XFS 100 years ago by Dr John G. Lindberg, there has been considerable advancement in understanding its pathogenesis and resulting clinical implications. The purpose of this paper is to summarise information regarding the epidemiology, pathophysiology, ocular manifestations and systemic associations of XFS with the objective of sharing clinical pearls to assist in early detection and enhanced management of patients.

Peripapillary Perfused Capillary Density in Exfoliation Syndrome and Exfoliation Glaucoma versus POAG and Healthy Controls: An OCTA Study

PURPOSE

To compare the peripapillary perfused capillary density (PCD) among eyes with exfoliation syndrome (XFS), exfoliation glaucoma (XFG), primary open-angle glaucoma (POAG), and controls.

DESIGN

Observational, cross-sectional study.

METHODS

Optical coherence tomography angiography (OCTA) images (4.5×4.5 mm) of the optic nerve head were obtained using a commercial spectral domain OCTA system (AngioVue Avanti RTVue-XR, OptoVue, Fremont, CA). Two concentric circles with 1.95-mm (inner) and 3.45-mm (outer) diameters were placed manually, producing an annulus of width 0.75 mm centered at the optic disc. PCD was calculated as the ratio of pixels associated with capillaries to the pixels in the annulus after large blood vessel removal. Continuous variables were assessed by analysis of variance and Tukey honest significant difference (HSD) test. Multiple linear regression analysis was performed to adjust for confounding factors.

RESULTS

Forty-three XFG eyes, 31 POAG eyes matched for visual field mean deviation, 33 XFS eyes, and 45 control eyes were analyzed. PCD demonstrated a progressive decrease from controls to XFS to POAG to XFG. Pairwise comparisons revealed significant differences in PCD between each pair of groups (all P<0.01) except for PCD between XFS and POAG (P = 0.08). A multivariable model adjusting for age and stage showed a more significant decrease in PCD in XFG compared with POAG (P = 0.001).

CONCLUSIONS

PCD was more significantly decreased in XFG compared with POAG eyes and in XFS compared with control eyes. OCTA provides the first quantitative evidence of the microvascular disturbance that accompanies XFS.

Exfoliation syndrome in Northern Nigeria

Purpose

To estimate the frequency of exfoliation syndrome (XFS) and its association with ocular diseases in Northern Nigeria.

Materials and methods

Consecutive patients who presented to the outpatient department of ECWA Eye Hospital Kano from February 2015 to May 2015 were included in the study. Each patient had a complete ophthalmic examination. The anterior segment examination included tonometry, gonioscopy, and detailed slit-lamp examination to assess for the presence or absence of exfoliation material, inflammatory cells, and other abnormal findings. Patients with exfoliation material on the anterior lens surface and/or pupillary margin in either or both eyes were considered to have XFS. Statistical analysis was performed using the Statistical Package for the Social Sciences version 16.0.

Results

A total of 620 patients living in Northern Nigeria from the 6 geopolitical zones were examined. The majority of them (34.5%) were indigenous Hausas. There was a male preponderance of 56.6%, while the mean age at presentation for examination in all age groups was 55.7±13.7 years. There were 9 patients with XFS; the frequency was 1.5%, with most of the patients being 70-80 years old. In patients who were ≥50 years, the frequency was 2.5%. Patients with XFS had a higher mean age of 68±4.9 years. The frequency of XFS among glaucoma patients was 4.4%, while among cataract patients it was 3.7%. No other associated ocular disease was found in the patients with XFS.

Conclusion

This study shows that XFS does exist in Northern Nigeria, as was found in the South. The prevalence of XFS was, however, not reported in the Nigerian National Blindness and Visual Impairment Survey. Therefore, a population-based study is still needed to determine the true prevalence of XFS in Northern Nigeria.

Prevalence of Exfoliation Syndrome in Estonia

Purpose

To estimate the prevalence of exfoliation syndrome (XFS) in Estonia.

Methods

A total of 766 residents, representing the demographics of Tartu, Estonia, were chosen by random sampling from the Estonian Population Database, and invited to participate in this study. Each patient underwent careful slit-lamp examination including applanation tonometry before and after pupil dilatation. Presence of XFS was confirmed after mydriasis as typical white-gray fluffy material on the anterior lens surface, and on the pupillary border as well on the corneal endothelium.

Results

A total of 424 subjects, 277 female and 147 male, participated in this study. The median age was 70 years (70 years in women and 71 years in men). The overall prevalence of XFS among the study participants in 1 or both eyes was 25.5% (25.2% in men and 25.6% in women). Intraocular pressure measured before and after dilatation was significantly higher in the XFS group. Glaucoma was significantly more frequent in the XFS group than the non-XFS group; 35.7% and 11.3%, respectively. Fifty percent of all patients with glaucoma had exfoliative glaucoma. Cataract was detected in 57.0% of cases in the XFS group compared to 39.5% in the non-XFS group (p=0.002). We found similar prevalence of systemic diseases in both groups for both genders. There was no difference between the 2 groups in visual acuity.

Conclusions

In this population-based cross-section study, XFS was found to be a frequent finding in Estonia. Exfoliation syndrome is a risk factor for glaucoma and cataract formation.

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.

The Prevalence of Pseudoexfoliation and the Long-term Changes in Eyes With Pseudoexfoliation in a South Indian Population

PURPOSE

To report the prevalence, long-term changes and associated factors for pseudoexfoliation (PEX) in a population aged 40 years and above from rural and urban south India.

MATERIALS AND METHODS

At baseline (the Chennai Glaucoma Study), 7774 subjects were examined. After 6 years, as a part of the incidence study, 133 of the 290 subjects diagnosed with PEX at baseline were reexamined for long-term changes. Participants had detailed examination at base hospital.

RESULTS

At baseline PEX was noted in 290 [3.73%, 95% confidence interval (CI), 3.3-4.2] subjects. It was associated with glaucoma in 24 (8.3%), ocular hypertension (OHT) in 21 (7.2%), and occludable angles in 24 (8.3%) subjects. The age-adjusted and sex-adjusted prevalence was 3.41% (95% CI, 3.39-3.43). Increasing age was a significant associated factor. Using the 40- to 49-year age group as a reference, the odds ratio increased from 8.4 (95% CI, 4.1-17.1) for the 50- to 59-year age group to 51.2 (95% CI, 25.8-101.6) for the 70 years and above age group. Other associated factors were rural residence (P<0.001), higher intraocular pressure (P<0.001), cataract (P<0.001), being underweight (P=0.01), manual labor (P=0.03), and aphakia (P<0.001). Of the 133 subjects reexamined, 8 (6.0%) subjects developed glaucoma and all had OHT at baseline. Rates of cataract surgery were (P<0.001) higher in subjects with PEX.

CONCLUSION

Prevalence of PEX was higher in rural population and baseline OHT was a significant factor for conversion to glaucoma.

Measurements of Corneal Thickness in Eyes with Pseudoexfoliation Syndrome: Comparative Study of Different Image Processing Protocols

Purpose

Comparative analysis of central and peripheral corneal thickness in PEX patients using three different imaging systems: Pentacam-Scheimpflug device, time-domain optical coherence tomography (OCT) Visante, and swept-source OCT Casia.

Materials and Methods

128 eyes of 80 patients with diagnosed PEX were examined and compared with 112 normal, non-PEX eyes of 72 cataract patients. The study parameters included 5 measured zones: central and 4 peripheral (superior, inferior, nasal, and temporal).

Results

The mean CCT in eyes with PEX syndrome measured with all three instruments was thicker than that in normal eyes. Corneal thickness measurements in the PEX group were statistically significantly different between Pentacam and OCT Casia: central corneal thickness (p = 0.04), inferior corneal zone (p = 0.01), and nasal and temporal corneal zones (p < 0.01). Between Pentacam and OCT Visante inferior, nasal and temporal corneal zones were statistically significantly different (p < 0.01). Between OCT Casia and OCT Visante, there were no statistically significant differences in measured parameters values.

Conclusion

The central corneal thickness in eyes with PEX syndrome measured with three different independent methods is higher than that in the non-PEX group, and despite variable peripheral corneal thickness, this one parameter is still crucial in intraocular pressure measurements.

Comparisons of retinal vessel diameter and glaucomatous parameters between both eyes of subjects with clinically unilateral pseudoexfoliation syndrome

Purpose

Pseudoexfoliation syndrome (PEX), the most common identifiable cause of open-angle glaucoma, might affect the retinal hemodynamics. To test this, we compared retinal vessel diameter and glaucoma-related parameters between eyes with pseudoexfoliation material (PE+) and fellow unaffected (PE-) eyes of patients with clinically unilateral PEX.

Methods

The medical records of 30 consecutive Japanese subjects were reviewed retrospectively. The retinal vessel diameters were measured and expressed as the central retinal arteriolar equivalent (CRAE) and central retinal venular equivalent (CRVE) using standardized software. During the chart review, we recorded glaucoma-related parameters including intraocular pressure (IOP), visual field mean deviation (MD) value, planimetrically measured vertical cup-to-disc (C/D) ratio, circumpapillary retinal nerve fiber layer thickness (cpRNFLT) and macular inner retinal thickness (mIRT) measured by spectral-domain optical coherence tomography, anterior chamber flare (ACF), corneal endothelial cell density (CECD), and number of antiglaucoma medications.

Results

Compared with PE- eyes, the CRAE, CRVE, MD, cpRNFLT and mIRT, and CECD were significantly lower in PE+ eyes; the IOP, vertical C/D ratio, number of antiglaucoma medications, and ACF were significantly higher in PE+ eyes (P<0.0001 for all comparisons). The CRAE, cpRNFLT, and MD were correlated positively with each other (ρ = 0.456–0.499, P<0.0001–0.0002) and negatively with the IOP (ρ = -0.562- —0.432, P<0.0001–0.0006). The vertical C/D ratio was correlated positively with the IOP (ρ = 0.483, P<0.0001) and negatively with the CRAE, cpRNFLT, and MD (ρ = -0.745–-0.479, P<0.0001–0.0001).

Conclusions

Deposition of PE can cause retinal vessel narrowing in arterioles and venules. The roles and mechanisms of retinal vessel narrowing in glaucoma pathogenesis need clarification.

Deep Sclerectomy with Nonabsorbable Implant (T-Flux) in Patients with Pseudoexfoliation Glaucoma

Purpose. To evaluate the effectiveness of deep sclerectomy with T-flux implant (DS T-flux) in patients with pseudoexfoliation glaucoma (PExG). Methods. 20 eyes of 18 patients with medically uncontrolled PExG have undergone DS T-flux implantation. Postoperatively we evaluated the IOP values and the frequency of complications. The minimum follow-up time was 12 months (20 eyes) and the maximum 24 months (10 eyes). Results. The mean preoperative IOP was 36.8 ± 8.7 mmHg. The IOP significantly decreased throughout all postoperative periods (P < 0.05) and reached 1 day after surgery 11.45 ± 6.6 mmHg; 3 months 13.45 ± 3.6 mmHg; 12 months 14 ± 2.8 mmHg; and 24 months 14.80 ± 2.4 mmHg. Complete success rate, defined as IOP ≤ 18 mmHg without medication, was 85% (17/20 eyes) at 12 months. Qualified success rate, defined as IOP ≤ 18 mmHg with or without medication, was 100% (20/20 eyes). The most frequent postoperative complications were mild hyphaema (9 patients, 45%), choroidal detachment (3 patients, 15%), and hypotony—IOP < 5 mmHg (2 patients, 10%). Conclusions. DS with T-flux implant is a safe and effective surgical treatment method for medically uncontrolled PExG. The number of complications is low.

Immunohistochemical analysis of microsomal glutathione S-transferase 1 and clusterin expression in lens epithelial cells of patients with pseudoexfoliation syndrome

Pseudoexfoliation syndrome (PEX) is an age-associated, sight disorder affecting elastic fibers in the eye and visceral organs but its exact etiology remains unknown. The purpose of the current study was to determine the morphology and ultrastructure of lens epithelial cells (LECs), and to use immunohistochemistry to examine localization of microsomal glutathione S-transferase 1 (MGST1) and clusterin. Anterior lens capsules were obtained from 24 patients (13 PEX and 11 controls) who underwent phacoemulsification. Immunohistochemistry was performed, using antibodies against MGST1 and clusterin, to determine their expression. The morphology and ultrastructure of LECs were evaluated by light and transmission electron microscopy, respectively. The PEX LECs were characterized by significantly lower MGST1 (P=0.0001) and clusterin expression (P=0.0005) compared with the control group patients. PEX LECs were also observed to have significantly increased thickness compared with the control group patients (P=0.0002). The current findings suggest that low MGST1 and clusterin expression levels may be an early clinical indicator of PEX, and that oxidative stress may serve an important role, but that the specific etiology of this disease has yet to be revealed.

Prevalence of pseudoexfoliation syndrome and its association with ocular and systemic diseases in Eskisehir, Turkey

AIM

To investigate the prevalence of pseudoexfoliation syndrome (PEX) and its associations with ocular and systemic diseases in a population sample aged over 40y.

METHODS

A total of 2356 subjects were randomly chosen for the sample population based on the database of the Turkish Statistical Agency in Eskisehir. Of the invited 2356 subjects, 2017 subjects participated, out of which 2009 were eligible for the study. Systemic diseases, drug use, smoking and body mass index were assessed using questionnaires. Measurements of central corneal thickness (CCT), anterior chamber depth (ACD) and intraocular pressure (IOP) were performed during June to December, 2015. After pupillary dilation, the anterior segment and lenses were evaluated using a slit lamp.

RESULTS

Prevalence of PEX in this sample was 5.0% (n=100). Of patients with PEX, 26% also had glaucoma. Incidence of cataracts, and using drugs for hypertension, cardiac and psychiatric conditions was higher in patients with PEX compared to normal cases (P<0.05). Hearing loss was more common in PEX cases (34.0% vs 5.4%; P<0.001). The mean CCT, ACD and IOP were not significantly different between PEX and non-PEX cases.

CONCLUSION

This study is the first population-based, randomized trial in Turkey. Prevalence of PEX in patients over 40 years old was found to be 5.0%. Besides glaucoma and cataract, hypertension, hearing loss, using drugs for cardiac and psychiatric diseases were associated with PEX.

Risk factors for corneal endothelial cell loss by cataract surgery in eyes with pseudoexfoliation syndrome

PURPOSE

The aim of this study was to investigate the factors associated with decreases in corneal endothelial cell density (ECD) resulting from cataract surgery in eyes with pseudoexfoliation syndrome (PEX).

METHODS

The clinical records of 78 eyes of 78 patients with PEX who had undergone cataract surgery were reviewed. ECD was measured preoperatively and at 3 months postoperatively with specular microscopy. Multiple regression analysis was used to assess the factors that were significantly related to the rate of ECD loss. Explanatory variables included age, preoperative ECD, pupil diameter, cataract grade, concomitance of glaucoma or diabetes mellitus, preoperative anterior chamber depth, surgery time, total time and power of ultrasound, performance of intraoperative pupillary enlargement manipulation, and postoperative aqueous flare intensity at 1 week and 1 month.

RESULTS

ECD before and after surgery was 2,464±337 cells/mm(2) and 2,400±347 cells/mm(2), respectively, with an ECD loss rate of 2.6%±5.1% (mean ± SD). Multiple regression analysis revealed that ECD loss was significantly associated with the cataract grade (P=0.019) and preoperative anterior chamber depth (P=0.023).

CONCLUSION

With modern small incision cataract surgery, the ECD loss varied with surgical invasions due to severe cataract and shallow anterior chamber, and the presence of PEX was least affected.

The Prevalence of Exfoliation Syndrome in an Iranian Population Aged 45-69 Years

PURPOSE

To determine the prevalence of exfoliation syndrome (XFS) and some of its related factors in an Iranian population aged 45-69 years.

METHODS

In the first phase of the Shahroud Eye Cohort Study, 5190 people in 300 clusters from Shahroud city in the northeast of Iran participated in the study. The second phase of the study was conducted 5 years later in 2014. Vision testing, refraction, slit lamp examination, and fundus examination were performed for all participants. In this study, XFS was determined by an ophthalmologist using slit lamp biomicroscopy.

RESULTS

Of the 5190 first phase study participants, 4737 participated in the second phase (response rate 91.3%). In this study, the prevalence of XFS was 0.46% (95% confidence interval, CI, 0.24-0.68%) and the prevalence of bilateral XFS was 0.20% (95% CI 0.07-0.33%). XFS prevalence in men was 0.74% (95% CI 0.28-1.20%) and in women 0.26% (95% CI 0.07-0.45%). In a multivariable-adjusted logistic regression model, age, sex, diabetes, smoking status, dyslipidemia, and hypertension were entered into the model as covariables, where older age (odds ratio, OR, 1.18, 95% CI 1.08-1.28) was the only variable that remained significantly associated with XFS prevalence.

CONCLUSION

The prevalence of XFS in this study was very low. Similar to other studies, age was a factor associated with this syndrome.