Evaluation of the effects of environmental factors and eating habits on exfoliation syndrome and glaucoma in a Turkish population

PURPOSE

This study aimed to assess the possible effect of environmental factors and eating habits on patients with the exfoliation syndrome (XFS) and exfoliative glaucoma (XFG) in a Turkish population.

METHODS

A questionnaire was applied to 1,000 individuals, including 290 patients with XFS, 210 patients with XFG, and 500 age- and sex-matched healthy control participants. Sociodemographic characteristics, home type and warming methods, living and working conditions (indoor-outdoor), dietary habits based on the the guidance of Turkey Dietary Guidelines, (Determination of Nutritional Status Report and Turkey National Nutrition and Health Survey) and using sunglasses were evaluated. The chi-square test, Student t test, and analysis of variance were used for the statistical analysis with SPSS v. 23.0 software.

RESULTS

The case-control groups were matched during data collection, and age and sex distribution in groups was analyzed; however, no difference was found. The average years and hours spent outdoor were statistically different between case and control groups (P < 0.05). The disease risk among individuals wearing sunglasses was 2.74 times less than that among those who did not wear sunglasses. Individuals born in the city had 1.46 times lower risk. Also, living out of the city until the age of 12 years increased the risk of getting the disease 1.36 times. In addition, while living in an apartment decreased the risk of disease, using a stove increased. The control groups had more healthy eating habits than the case groups.

CONCLUSION

This case-control study showed that time spent outdoors, wearing sunglasses, home type, heating method, and eating habits might be associated with XFS and XFG.

Evaluating the impact of ocular UV exposure for the development for pseudoexfoliation syndrome in a South Indian population

CLINICAL RELEVANCE

Pathophysiology of pseudoexfoliation syndrome (XFS) can be influenced by environmental factors such as solar exposure/occupational factors and genetic factors.

BACKGROUND

The study aims to assess the association of lifetime ocular UV exposure and its impact on the risk of development of XFS.

METHODS

All eligible subjects underwent a comprehensive ocular examination. XFS was defined as precipitates on the pupillary border, cornea, and angle of anterior chamber or lens in at least one eye without any clinical signs of glaucoma. A standardised questionnaire was administered to assess the lifetime UV exposure. Conjunctival ultraviolet autofluorescence (CUVAF) photography was taken to detect the conjunctival changes with exposure to UV radiation. Ascorbic acid concentration in the aqueous humour was measured.

RESULTS

A total of 404 subjects of which 274 (controls) and 130 (XFS cases) were studied. There were 204 males (50.5%) and 200 females (49.5%).Lifetime UV exposure (OR: 1.14, 95% CI: 1.02-1.30, p: 0.032), CUVAF damage (OR: 1.03, 95% CI: 1.01-1.06, p: 0.008) and outdoor worker (OR: 1.87, 95% CI: 1.18-3.00, p: 0.008) were positively associated with XFS. Usage of spectacles (OR: 0.63, 95% CI: 0.39-0.95, p: 0.030) and ascorbic acid concentration in aqueous (OR: 0.47, 95% CI: 0.23-0.99, p: 0.038) were found to be protective against XFS.

CONCLUSION

Besides genetic factors, environmental factors such as lifetime ocular UV exposure and outdoor work are significantly associated with the risk of XFS. CUVAF can be used as a non-invasive tool to detect preclinical sun damage in outdoor workers.

[Research advances in the pathogenesis of exfoliative glaucoma]

Exfoliative glaucoma is a type of glaucoma secondary to pseudoexfoliation syndrome. In recent years, great progress has been made in the research of pathogenesis and risk factors of exfoliative glaucoma. A variety of risk genes, abnormal growth factors and cytokines, changes in the anterior and posterior segments have been found. Based on the systematic summary of these achievements, this article points out the problems that need to be further studied, so as to provide a reference for future research in this field.

Regulatory cytokines prescribe the outcome of the inflammation in the process of pseudoexfoliation production

BACKGROUND

The purpose of this study is to reveal the participation of different regulatory cytokines within the process of pseudoexfoliation (PEX).

METHODS

Our study included 140 patients referred to cataract surgery with early and late stage of pseudoexfoliation syndrome (XFS) or pseudoexfoliation glaucoma (XFG). Humor and serum levels of cytokines: transforming growth factor beta (TGF-β), platelet-derived growth factor (PDGF), epidermal growth factor (EGF), insulin-like growth factor (IGF), IL-8 and interferon-inducible T cell alpha chemoattractant (ITAC) were measured in a sample using high sensitivity enzyme-linked immunoabsorbent assay (ELISA) kit.

RESULTS

Our results indicate that profibrotic action induced by increasing TGF-β and PDGF locally activates fibrous tissue production in the early XFS with a prolonged effect of PDGF (late XFS) and finally (XFG stage) it is dominantly controlled by EGF and IGF. ITAC overrides angiogenetic effects of IL-8 in XFG.

CONCLUSION

Based on our findings, local chronic inflammation in the eye is accompanied by the secretion of different profibrotic cytokines (TGF-β, PDGF, EGF, IGF, IL-8) without angiogenesis due to effects of ITAC.

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.

The History of Exfoliation Syndrome

The first description of exfoliation syndrome (XFS) was presented by John Gustaf Lindberg in his doctoral thesis 100 years ago. The syndrome is an age-related disorder in which abnormal fibrillar extracellular material is produced and accumulates in several ocular tissues. Once thought to be peculiar to Scandinavia, XFS is found in almost every race and ethnic group. Subsequent studies provided evidence for the systemic nature of XFS, which involves an aberrant connective tissue metabolism throughout the body. There is a prominent association with zonular instability. This study presents the developments in the understanding of the pathomechanism and clinical significance of XFS and explains the problem of terminology in the description of XFS and pseudoexfoliation.

LOXL1 Polymorphisms: Genetic Biomarkers that Presage Environmental Determinants of Exfoliation Syndrome

An agnostic high throughput search of the genome revealed a robust association between LOXL1 genetic polymorphisms and exfoliation syndrome (XFS), a discovery that likely would not have been possible with candidate or family-based gene search strategies. While questions remain regarding how LOXL1 gene variants contribute to XFS pathogenesis, it is clear that the frequencies of disease-related alleles do not track with the varying disease burden throughout the world, prompting a search for environmental risk factors. A geo-medicine approach revealed that disease load seemed to increase as a function of the distance from the equator. The exact reason for this extraequatorial disease distribution pattern remains unclear, but a greater amount of time spent outdoors is a robust risk factor for XFS, suggesting climatic factors such as ocular solar exposure and colder ambient temperature may be involved in disease pathogenesis. Prospective studies have also implicated higher coffee consumption and lower dietary folate intake in association with incident XFS. The discovery of environmental risk factors for XFS suggests that preventive measures may help to reduce ocular morbidity from XFS.

A Role for Clusterin in Exfoliation Syndrome and Exfoliation Glaucoma?

The multifunctional protein clusterin (CLU) is a secreted glycoprotein ubiquitously expressed throughout the body, including in the eye. Its primary function is to act as an extracellular molecular chaperone, preventing the precipitation and aggregation of misfolded extracellular proteins. Clusterin is commonly identified at fluid-tissue interfaces, and has been identified in most body fluids. It is a component of exfoliation material, and CLU mRNA is reduced in eyes with exfoliation syndrome compared with controls. SNPs located in the CLU genomic region have been associated with Alzheimer disease (AD) at the genome-wide level and several CLU SNPs located in an apparent regulatory region have been nominally associated with XFS/XFG in Caucasians with European ancestry and in south Indians. Interestingly, clusterin associates with altered elastic fibers in human photoaged skin and prevents UV-induced elastin aggregation in vitro. In light of the known geographic risk factors for XFS/XFG, which could include UV light, investigations of CLU-geographic interactions could be of interest. Future studies investigating rare CLU variation and other complex interactions including gene-gene interactions in XFS/XFG cases and controls may also be fruitful. Although CLU has been considered as a therapeutic target in AD, cancer and dry eye, a role for clusterin in XFS/XFG needs to be better defined before therapeutic approaches involving CLU can be entertained.

Is Autophagy Dysfunction a Key to Exfoliation Glaucoma?

In this short report we review previous work toward the identification of the protein and cellular sources of exfoliation glaucoma and described our recent finding on dysfunction of autophagy in Tenon capsule fibroblasts obtained from exfoliation syndrome glaucoma patients at the time of surgery and discuss the potential implications of these findings for understanding the cellular sources of the disease.

Iris alterations after DSAEK

OBJECTIVE

To evaluate a series of case that developed iris changes after performing Descemet's stripping automated endothelial keratoplasty (DSAEK).

METHODS

Retrospective study of eyes that developed iris abnormalities, such as pupil ovalisation, iris atrophy, iridocorneal synechiae, mydriatic pupil, and pigmentary changes after performing DSAEK in a tertiary hospital.

RESULTS

In a series of the first 32 DSAEK procedures performed, new single or mixed iris alterations were observed in 12 eyes (37.5%). Iris-corneal synechiae were observed in 7 eyes, corectopias in 9 eyes, iris atrophy in 3 cases, and one case developed an areflexic mydriatic pupil. Long-term pigment dispersion at the edge of the lenticule was observed in 12 eyes. The alterations occurred after three months from the surgery. In the evaluation of the associated factors, malignant glaucoma had occurred in 1 case, 2 eyes had required a second surgery, one case by re-DSAEK, and the other one by removing the intraocular lens due to lens opacification. Two cases had a shallow anterior chamber. No relationship was found between the thickness of the peripheral lenticule and the presence of synechiae.

CONCLUSION

Iris changes regarding DSAEK are possible. A discussion is presented on the relationship between increased intraocular pressure due to air in anterior chamber and its relationship with ischaemia and secondary alterations in the iris.

Exfoliation syndrome: a disease with an environmental component

PURPOSE OF REVIEW

Exfoliation syndrome (XFS), the most common cause of secondary open angle glaucoma, is associated with significant ocular morbidity. Recent studies have pointed toward environmental components that may alter the risk of XFS development. This review focuses on the recent studies elucidating the role of environmental factors that play a role in the development of exfoliation syndrome.

RECENT FINDINGS

In XFS, aberrant microfibril formation emanating from the cell-extracellular matrix interface admixes with other macromolecules and is cross-linked by lysyl oxidase like 1 (LOXL1) activity. A common gene variant in the LOXL1 enzyme, an enzyme critical for enhancing the tensile strength of collagen and elastin in extracellular matrices, has been found in approximately 90% of XFS cases. However, approximately 80% of controls also have disease-associated LOXL1 gene variants. These findings point toward other nongenetic factors influencing the development of XFS. Increasing latitude, solar radiation, climatic variables and dietary factors such as high coffee consumption and low dietary folate intake are among the nongenetic factors associated with increased risk of XFS.

SUMMARY

A greater understanding of the environmental components associated with XFS may lead to lifestyle preventive strategies to ameliorate disease burden.

Relation between time spent outdoors and exfoliation glaucoma or exfoliation glaucoma suspect

PURPOSE

To evaluate the relation between time spent outdoors at various life periods and risk of exfoliation glaucoma or exfoliation glaucoma suspect.

DESIGN

Retrospective cohort study in the United States.

METHODS

Participants (49 033 women in the Nurses Health Study and 20 066 men in the Health Professionals Follow-up Study) were 60+ years old, were free of glaucoma and cataract, reported eye examinations, and completed questions about time spent outdoors in direct sunlight at midday at 3 life periods: high school to age 24 years, age 25-35 years, and age 36-59 years (asked in 2006 in women and 2008 in men). Participants were followed biennially with mailed questionnaires from 1980 women/1986 men to 2010. Incident cases (223 women and 38 men) were confirmed with medical records. Cohort-specific multivariable-adjusted rate ratios from Cox proportional hazards models were estimated and pooled with meta-analysis.

RESULTS

Although no association was observed with greater time spent outdoors in the ages of 25-35 or ages 36-59 years, the pooled multivariable-adjusted rate ratios for ≥11 hours per week spent outdoors in high school to age 24 years compared with ≤5 hours per week was 2.00 (95% confidence interval = 1.30, 3.08; P for linear trend = .001). In women, this association was stronger in those who resided in the southern geographic tier in young adulthood (P for interaction = .07).

CONCLUSIONS

Greater time spent outdoors in young adulthood was associated with risk of exfoliation glaucoma or exfoliation glaucoma suspect, supporting an etiologic role of early exposures to climatic factors.

Pseudoexfoliation syndrome and coronary artery ectasia

AIMS

To determine whether pseudoexfoliation syndrome is associated with coronary artery ectasia or not.

METHODS

This cross-sectional study was undertaken at Bulent Ecevit University's Ophthalmology Department with the participation of the Cardiology Department. Eighty consecutive patients who underwent coronary angiography and were classified into two groups-those diagnosed with a normal coronary artery (n=40) and those diagnosed with coronary artery ectasia (n=40)-were included in the study. Pseudoexfoliation was diagnosed if typical exfoliation material was found to be present on the anterior surface of the lens, the iris, or at the pupillary border on slit-lamp examination. Age, sex, presence of pseudoexfoliation material, hypertension, diabetes mellitus, hyperlipidemia rates, cigarette smoking history, and family history of coronary artery disease were compared between the two groups. The continuous variables were compared by using the independent sample t-test or the Mann-Whitney U-test, and the categorical variables were compared using Pearson's χ(2)-test or Fisher's Exact χ(2)-test for the two groups.

RESULTS

There was no difference in demographic data of both groups. The presence of pseudoexfoliation material was more common in patients with coronary ectasia compared with controls [(n=21 (52.5%) vs n=8 (20%), P=0.005)]. In all patients, there was a higher glaucoma rate in the patients with pseudoexfoliation syndrome [n=7 (24.1%), 6 CAE (+), 1 CAE (-)] than in the normal patients [n=2 (3.9%), 2 CAE (-)] (P=0.010).

CONCLUSIONS

In this study, we found a possible association of pseudoexfoliation and coronary artery ectasia. Coronary artery ectasia patients had higher prevalence of pseudoexfoliation.

[Pseudoexfoliation syndrome: pathogenesis of impairment of vegetative sympathetic innervation associated with cervical spine disorder]

The results of magnetic resonance imaging of the cervical spine in 33 patients with mono- and bilateral pseudoexfoliation syndrome (PES) and cervical osteochondrosis are presented. The protrusion of intervertebral discs localized in the site of ciliospinal center and rarer in the site of superior cervical sympathetic ganglion is found. The protrusion of intervertebral discs in patients with PES was associated with compression of spinal roots significantly more often than in patients with cataract and osteochondrosis but without PES (control group). The side of protrusion and compression of spinal roots corresponded to the side of PES in more than 50% of cases. Compressive disorders of cervical spinal structures may be of considerable importance in pathogenesis of PES.

Spontaneous idiopathic true exfoliation of the anterior lens capsule during capsulorhexis

We report a unique case of spontaneous per-operative idiopathic development of true exfoliation of the anterior lens capsule during capsulorhexis. A 45 year old female who underwent phacoemulsification for a cataract in the left eye, developed a partial split (the double ring sign) and eventual complete separation of the superficial lamina of the lens capsule during capsulorhexis. Radial tears developed in the remaining lamina making the capsular bag unstable. The surgery was converted to manual nucleus expression. An intra ocular lens was implanted via scleral fixation. The final best corrected visual acuity in the left eye was 6/6. The patient is comfortable with the vision. Though a rare event, the surgeon must always be alert to the development of spontaneous idiopathic per operative true exfoliation of the lens capsule.

Complications of cataract surgery in patients with pseudoexfoliation syndrome

BACKGROUND

The weak zonule's predisposition to complications during conventional cataract surgery is one of the common risk factor for poor visual acuity after surgery. The present study was conducted to determine the frequency and types of complications during cataract surgery in patients with Pseudoexfoliation Syndrome.

METHODS

A cross sectional descriptive study based on non probability sampling of patients having pseudoexfoliation syndrome admitted for cataract surgery in tertiary care hospitals was carried out spread over 4 years. The data of all variables of interest were entered and analyzed through SPSS version 15.0.

RESULTS

A total of 200 eyes of 122 patients having Psuedoexfoliation were included in the study. Vitreal prolapse in 21 (10.5%) and posterior capsular rupture in 18 (9%) patients were the most common complications seen in Pseudoexfoliation. Damage to sphincter pupillae in 16 (8%), iridodialysis in 2 (1%), decentration of IOL in 8 (4%) and hyphaema in 2 (1%) patients was seen. Zonular dialysis in 8 (4%), retained lens matter in 12 (6%) and lens dislocation was seen in 6 (3%) patients.

CONCLUSION

Patients with pseudoexfoliation are at increased risk for development of complications. Ophthalmologists should stress to increase awareness among general public for the proper diagnosis and convince patients for proper and regular follow up visits to the hospital.

Is exfoliation syndrome a sign of systemic vascular disease?

Exfoliation syndrome (ES) is an age-related disorder in which greyish-white flakes accumulate in different tissues in the anterior eye. Its pathogenesis is not completely known, but it results in electron-dense microfibrils. The finding that these can be seen outside the eye in many visceral organs inspired the theory that ES might be a part of a generalized disorder. It was postulated that ES might contribute to increased morbidity, mainly of systemic vascular diseases. This review is a summary of the existing knowledge. The prevalence of arterial hypertension (AHT) in elderly populations is > 30%. No differences have been found in the frequency of AHT among patients with ES or exfoliative glaucoma (EG) compared with those with primary open-angle glaucoma (POAG) or no ES. There are conflicting reports of frequencies of ischaemic heart disease (IHD). A recent registry-based study that used uniform criteria for IHD found no difference in the rate of IHD between patients with EG and those with POAG. However, findings of elevated homocysteine levels in the plasma and aqueous humour of patients with ES or EG suggest an increased vascular risk. No studies have yet been conducted to assess possible links between ES and systemic vascular diseases. In a single-blind study, ES was associated with abdominal aortic aneurysm, but this was not found in a large, cross-sectional investigation. The frequency of ES in patients with diabetes mellitus (DM) is only about half of that when compared in patients with no ES or with POAG. This finding warrants further studies. Molecular genetics research has found no common denominator for ES and the vascular diseases. There is no evidence that ES or EG are related to increased mortality for cardiovascular diseases. Further large-scale, randomized clinical studies are required. At present there are no known medical indications that infer an increased systemic vascular risk or imply a need for the complete internal medical examination of a symptom-free patient with newly diagnosed ES in the eye.

Cataract phacoemulsification and intraocular pressure in glaucoma patients

PURPOSE

To evaluate the influence of recently performed cataract phacoemulsification in glaucomatous eyes on postoperative intraocular pressure (IOP).

MATERIAL AND METHODS

100 eyes of 86 glaucoma patients who underwent cataract phacoemulsification with simultaneous intraocular lens implantation, were retrospectively analyzed. The patients were divided into two groups: I--61 patients (71 eyes) with open angle glaucoma, and II--25 patients (29 eyes) with angle closure glaucoma. Both groups were subdivided into two subgroups, depending on presence of symptoms of pseudoexfoliation (PEX) syndrome (A = with, and B = without symptoms of PEX syndrome). All patients were examined in the department where the surgeries were performed; before surgery, on the first day after the procedure, and again during the last follow-up examinations, 6 to 30 months after the procedure.

RESULTS

Before surgery, the intraocular pressure (IOP) was at mean value of 19.02 +/- 4.55 mmHg in group I, and 20.01 +/- 6.43 mmHg in group II. On the first day after surgery, the IOP was 17.42 +/- 7.17 and 20.36 +/- 8.98 mmHg, respectively. lOP exceeding 20 mmHg was found in 7 eyes in group I, and in 6 eyes in group II. During the last follow-up examinations the lOP was 14.59 +/- 3.73 and 14.01 +/- 4.50 mmHg, respectively, and was lower than measured before surgery, by an average of 4.43 mmHg in group I (P < 1 x 10(-5)), and 6.00 mmHg in group II (P < 1 x 10(-4)). In both groups, the reduction of lOP in patients with PEX was even more remarkable. The number of glaucoma medication necessary to control the pressure was reduced on average by 0.28 in group I, and 0.31 in group II.

CONCLUSIONS

Phacoemulsification done on glaucomatous eyes results in lowering of lOP, and hence the dosage of glaucoma drugs over the long term can be simplified or even discontinued.

Posterior synechias following implantation of a foldable silicone iris-fixated phakic intraocular lens for the correction of myopia

A 45-year-old white woman with unilateral high myopia had uneventful implantation of a -9.0 diopter, foldable, iris-fixated Artiflex I anterior chamber phakic intraocular lens (pIOL) (Ophtec B.V.) in the right eye. Despite application of topical antibiotic and steroid agents for 4 weeks after surgery, iris pigment dispersion developed on the anterior surface of the crystalline lens. Two weeks later, the iris dispersion increased and posterior synechias developed from the iris to the crystalline lens next to the pIOL haptic at the 3 o'clock position. Consequently, pIOL re-enclavation was performed without surgically removing the posterior synechias. Initial and interim mydriatic and steroid eyedrops were administered 4 times a day. Regular follow-up examinations after re-enclavation (at 2, 3, 6, 12, and 24 months) confirmed a stable pIOL position by Scheimpflug photography. Two years after implantation, posterior synechias persisted at the 3 o'clock position, with iris dispersion on the crystalline lens and the posterior side of the pIOL, but with no signs of anterior chamber inflammation and no visual acuity loss.

Pigmentary dispersion syndrome with a secondary piggyback 3-piece hydrophobic acrylic lens

We describe a case of pigmentary dispersion syndrome resulting from secondary piggyback implantation of a 3-piece hydrophobic acrylic squared-edged intraocular lens (IOL) in the ciliary sulcus. The intraocular pressure remained elevated despite pharmacological treatment, with a heavily pigmented trabecular meshwork. The piggyback IOL was subsequently explanted and replaced by a silicone IOL with smooth round edges. Examination of the explanted IOL under light and scanning electron microscopy showed clusters of pigment epithelial cells located around the periphery of the anterior optic surface.

Spontaneous late in-the-bag intraocular lens dislocation after can-opener capsulotomy: case report

We report a case of a 58-year-old man presenting with a spontaneous and late in-the-bag intraocular lens dislocation to the vitreous. A previous uneventful extracapsular cataract extraction with can-opener style capsulotomy and implantation of a polymethylmethacrylate three-piece lens was performed and, two years after the surgery, the patient developed capsule contraction syndrome with a fibrotic ring formation and dislocation of the intraocular lens. Although uncommon and related mainly to continuous curvilinear capsulorhexis, capsule contraction syndrome occurs in patients undergoing extracapsular cataract surgery with can-opener style and polymethylmethacrylate lens implantation, and can be the causative factor of intraocular lens dislocation.

Vitamin deficiency and hyperhomocysteinemia in pseudoexfoliation glaucoma

Pseudoexfoliation syndrome (PEX) is a systemic disorder characterized by the deposition of an abnormal fibrillar material in ocular and various extraocular tissues. It represents the most common identifiable cause of glaucoma (PEX glaucoma = PEXG). Due to similar pathogenetic mechanisms, glaucoma has been called "ocular Alzheimer's disease". PEXG and Alzheimer's disease share common associations such as the higher prevalence of hyperhomocysteinemia in both disorders. In order to investigate the cause of hyperhomocysteinemia in PEXG, we evaluated B-vitamin levels (folate, B12, B6) and their associations with homocysteine (Hcy) in plasma of 70 PEXG patients and 70 control subjects. Folate, vitamin B12 and B6 levels were significantly decreased and associated with elevated Hcy levels in PEXG. Low B-vitamin levels in PEX might also help explain, at least in part, the higher prevalence of B-vitamin deficiency in disorders associated with PEX such as Alzhemier's disease.

Sunlight and incidence of pterygium on Croatian Island Rab--epidemiological study

The aim of this epidemiologic study, on small island Rab, in North Adriatic Sea, is to estimate correlation between climatic factors, specially chronic exposure to strong visible and UV light, and appearance of pterygium and exfoliation syndrome. In the first group of population which live in a village and who are agriculturists and fishermen (480 persons) appearance of pterygium is in 23% (16% in males and 7% in females), but 0.0% in urban people (61 people). The appearance of exfoliation syndrome was in the first group of agriculturists and fishermen population in 21%, of which 19% of males and 2% of females, and in urban people 0.0%. The higher intraocular pressure in exfoliation syndrome was 92%. All population in this examination were in the highest age (mean age is 65-80 years). Chronic exposure to sunlight caused the high percentage appearance of pterygium and exfoliation syndrome.

[Pseudo-exfoliative syndrome--etiology, clinical aspects, diagnosis]

The pseudoexfoliative syndrome is a systemic anomaly that primarily affects the eye. Many etiopathogenic mechanisms were found using ELISA, PCR and western immunoblot. The presence of the pseudoexfoliative material causes important changes to the cornea, camerular angle, lens and zonules. Cataract surgery in pseudoexfoliative syndrome is difficult. Pseudoexfoliative glaucoma is aggressive, with great pressure differences between the two eyes, also with important circadian variations of intraocular pressure and has a reserved prognostic.

Two Cases of True Exfoliation of the Lens Capsule after Cataract Surgery

True exfoliation of the lens capsule is known to be associated with glassblower's cataract, which is caused by extended exposure to excessive heat. Furthermore, inflammation and trauma are also considered to be predisposing factors. We report two cases of true exfoliation that were confirmed after cataract surgery. Neither patient exhibited true exfoliation before cataract surgery. In addition, neither patient had a history of occupation with exposure to excessive heat, inflammation or trauma. We observed the anterior lens capsules of these two patients with slit-lamp microscopy before and after cataract surgery. True exfoliation disappeared by adhering to the anterior capsule in both cases, and there were no complications during the observation period.

Depression and anxiety in patients with pseudoexfoliative glaucoma

OBJECTIVE

This study aimed to determine whether patients with pseudoexfoliative glaucoma (PXG), associated with vascular disorders, have more depressive and anxiety symptoms than patients with primary open-angle glaucoma (POAG) and controls without glaucoma. The vascular depression model was tested in this study.

METHOD

The sample consisted of 41 PXG patients, 32 POAG patients and 40 controls. Each subject was diagnosed as having PXG or POAG or chosen as a control patient by an ophthalmologist and then evaluated by a psychiatrist. The Structured Clinical Interview for DSM-IV, Turkish version; Hamilton Depression Rating Scale (HDRS); Hamilton Anxiety Rating Scale (HARS); Mini Mental State Examination; and Montgomery-Asberg Depression Rating Scale (MADRS) were administered to all subjects.

RESULTS

The HDRS and MADRS scores of the PXG patients were significantly higher than those of the POAG and the control group (chi(2)=9.858, p=.007 and chi(2)=11.618, p=.003, respectively). The HARS scores did not show a significant difference between the patients with PXG or POAG and the control subjects (chi(2)=1.615, p=.446). In each of the three groups, there was no correlation between the HDRS, HARS or MADRS scores and any of the following parameters: duration of glaucoma, medical treatment, visual acuity, intraocular pressure, perimetric stage, cup-disc ratio and number of glaucoma operations (p>.05).

CONCLUSION

A relationship between PXG and severity of depressive symptoms was shown by our data. However, no significant difference could be found between the anxiety levels of the three groups.

Anterior segment imaging using optical coherence tomography and ultrasound biomicroscopy in secondary pigmentary glaucoma associated with in-the-bag intraocular lens

A 43-year-old man with high myopia developed unilateral pigmentary glaucoma with recurrent episodes of painless blurred vision in the left eye following uneventful phacoemulsification. Bilateral cataract surgery was performed with capsular bag implantation of a +4.00 diopter AcrySof MA60 intraocular lens (IOL) (Alcon Laboratories) followed by a neodymium:YAG laser capsulotomy. Secondary iatrogenic dispersion syndrome in the left eye with subsequent intraocular pressure elevation was suspected in the presence of anterior chamber pigmented cells, circular epithelial iris loss around the pupil, and trabecular hyperpigmentation. Close contact between the edge of the IOL and the posterior pigmented iris epithelium, which was clinically suggested by anterior biomicroscopy, was documented by ultrasound biomicroscopy and optical coherence tomography of the anterior segment.

[Advanced glycation end products and pseudoexfoliation--correlation between clinical outcome and histological findings]

BACKGROUND

Pseudoexfoliation syndrome (PXS) as a stress-induced microfibrillopathy often shows a prolonged postoperative course. Formation of advanced glycation end products (AGEs) might be also associated with an increased oxidative stress. This study investigated for the first time immunohistochemically lens capsules of PXS patients for the AGE carboxymethylysine (CML) and correlated the findings with the clinical outcome of the patients.

METHODS

55 patients (22 male, 33 female; mean age 73.9 +/- 14.1 years) with PXS and pseudoexfoliation glaucoma (PXG) after cataract extraction were included. All lens capsules could be investigated immunohistochemically for the AGE CML. Both preoperative biometric data as well as intra- and postoperative courses were included in the investigations, followed by a correlation analysis of the immunohistochemical findings.

RESULTS

29 PXS and 26 PXG patients with a mean axial length of 23.1 +/- 1.1 mm were explored. Both groups showed a postoperative decrease of intraocular pressure and a moderate increase of visual acuity. Intraoperatively, 6 zonulolyses occurred and postoperatively 11 patients showed problems like increases of intraocular pressure. Immunohistochemically, CML could be detected in most of the epithelial cells of the lens capsules but only in a small part of the pseudoexfoliation (PEX) fibrils. A correlation between positive CML immunoreaction and the clinical course was not detectable.

CONCLUSIONS

Cataract extraction in patients with PEX glaucoma shows different specialities and risks. The AGE CML was detectable in human lens capsules. A direct correlation between clinical course and immunohistochemical reaction of the PEX fibrils could not be found. Overall, CML seems not to be a valuable predictive factor for the clinical course in patients with PXS and PXG.

Current concepts in the pathogenesis and management of exfoliation syndrome and exfoliative glaucoma

Exfoliative glaucoma is a common, sight-threatening disease that develops as a consequence of exfoliation syndrome. There are important differences in the clinical appearance, course, and prognosis of exfoliative glaucoma versus primary open-angle glaucoma. At the clinical, biochemical, and cellular levels, exfoliative glaucoma is a distinct entity, with an intriguing mechanism of development and numerous systemic manifestations that require further elucidation. The subtlety of clinical signs results in the diagnosis of exfoliative glaucoma often being overlooked and resulting in less-than-ideal management. We provide an overview of recent studies investigating the medical, laser, and surgical therapy of exfoliative glaucoma, with a focus on innovative approaches that may slow the progression of, or even prevent, the development of exfoliation syndrome and exfoliative glaucoma.

[Pseudoexfoliation syndrome--etiopatogenesis and clinical course]

Pseudoexfoliation syndrome is an ocular manifestation of a systemic elastosis. Exact etiology of this condition remains unknown. The basic pathogenetic concept of PEX is a pathological process of the extracellular matrix, characterized by the excessive production of an abnormal extracellular material which aggregates and accumulates and is not degraded in vivo. This material is produced primarily by the non pigmented epithelium of the ciliary body, the posterior iris pigment epithelium, and the preequatorial lens epithelium, while the corneal endothelium, trabecular cells, and vascular endothelia and smooth muscle cells of the iris have also been implicated. PEX material has a complex glycoprotein/proteoglycan, composition containing glycosaminoglycans (heparan sulfate, chondroitin sulfate, dermatan sulfate, hyaluronic acid). The prevailing presence of elastic fiber epitopes, mainly elastic microfibrillar components (elastin, vitronectin, amyloid P, fibrillin-1, LTBP-1), has led to the current theory explaining PEX as a type of elastosis, affecting especially elastic microfibrils. Ocular deposition of pseudoexfoliation material can lead to many complications in intraocular surgery like increased risk of zonular dehiscence, capsular rupture, vitreous loss during cataract extraction. Special attention is required before, during and after surgery.

Asymmetric pigmentary glaucoma in a patient with Marfan’s syndrome

BACKGROUND

No relationship between Marfan's syndrome and pigmentary glaucoma has previously been described in the ophthalmic literature. We describe the case of a patient with Marfan's syndrome who had bilateral pigment dispersion syndrome and asymmetrical glaucoma.

METHODS

A 34-year-old man with Marfan's syndrome developed pigment dispersion bilaterally. In the right eye, elevated intra-ocular pressure was associated with marked glaucomatous excavation of the right disc and corresponding visual field loss. A localised zonular dehiscence was present at the 6 o'clock position in the right eye.

RESULTS

Ultrasound biomicroscopy showed marked iris concavity in the right eye, increased iridolenticular contact and superior subluxation of the right lens, resulting in increased dispersion of pigment unilaterally. This explains the asymmetric pattern of the glaucomatous damage.

CONCLUSIONS

Asymmetrical progression of pigmentary glaucoma is uncommon and should prompt a search for some other mechanical factor, which might increase the iridozonular contact on one side or reduce it on the other. The association between the two syndromes in this patient was most likely mechanical due to reduced fibrillin expression throughout the eye and particularly in the iris and the lens zonules, resulting in loss of iris tensile strength and marked iris concavity as well as zonular weakness and partial lens subluxation.

Pigment dispersion and Artisan phakic intraocular lenses

PURPOSE

To validate the theory that crystalline lens rise can be used as a safety criterion to prevent pigment dispersion in eyes with an Artisan phakic intraocular lens (IOL) (Ophtec BV).

SETTING

Monticelli Clinic, Marseilles, France.

METHOD

A comparative analysis of crystalline lens rise in 9 eyes with pigment dispersion and 78 eyes without dispersion was performed. All eyes had previous implantation of an Artisan IOL. Anterior segment imaging was done using an anterior chamber optical coherence tomography (AC OCT) prototype. Crystalline lens rise was defined by the distance between the anterior pole of the crystalline lens and the horizontal plane joining the opposite iridocorneal recesses.

RESULTS

The study confirmed that crystalline lens rise can be considered a safety criterion for implantation of Artisan-type phakic IOLs. The higher the crystalline lens rise, the greater the risk for developing pigment dispersion in the area of the pupil. This complication occurred more frequently in hyperopic eyes than in myopic eyes. Results indicate there is little or no risk for pigment dispersion if the rise is less than 600 microm; 67% of eyes with a rise of 600 microm or more developed pupillary pigment dispersion. In some cases in which the IOL was loosely fixated, there was no traction on the iris root and dispersion was prevented or delayed.

CONCLUSIONS

Crystalline lens rise should be considered a new safety criterion for Artisan phakic IOL implantation and should also be applied to other types of phakic IOLs. The distance remaining between the crystalline lens rise and a 600 microm theoretical safety level allows one to calculate how long the IOL can safely remain in the eye.

Secondary pigmentary glaucoma associated with piggyback intraocular lens implantation

A 51 year-old man developed bilateral pigmentary glaucoma with uncontrolled intraocular pressure (IOP) and signs of pigmentary dispersion syndrome after piggyback intraocular lens (IOL) implantation. Cataract surgery had been performed with in-the-bag implantation of poly(methyl methacrylate) IOLs in both eyes. Increasing myopia was subsequently corrected with implantation of an AcrySofIOL (Alcon Laboratories) in the ciliary sulcus of each eye. After the second implantation, the IOP was unresponsive to antiglaucoma medications, the visual field was damaged, and the visual acuity decreased. Ultrasound biomicroscopy showed that the haptics and the sharp edge of the IOL were chafing the posterior surface of the iris. After the IOL in the sulcus was removed, the IOP was stabilized by medications. This case highlights the importance of the IOL choice for sulcus implantation to avoid the complications of pigmentary dispersion syndrome.

Pseudoexfoliation syndrome: pathological manifestations of relevance to intraocular surgery

Pseudoexfoliation syndrome (PEX) is a common ocular condition often associated with the need for intraocular surgery. Although results of cataract and glaucoma filtering surgery in eyes with PEX in the early stages of the disease may be comparable to those in eyes without PEX, in the later stages morbidity is significantly increased due to periocular surgical complications and the outcome is worse. Surgical and postoperative difficulties are often multifactorial and are directly related to the pathological changes of PEX on intraocular structures. Recent years have seen a large increase in the understanding of the effects of PEX on the various ocular tissues. Although the visible areas of the anterior capsule are most obviously involved, this is only a small part of the picture and of least significance. Biomicroscopically invisible changes of the zonules and their attachments are of greatest consequence. There is also distinct, often active, involvement of almost all tissues of the anterior segment of the eye, many of which have important implications for the anterior segment surgeon including iridopathy, iris vasculopathy (including persistent breakdown of the blood-aqueous barrier and anterior segment hypoxia), ciliary body involvement and keratopathy. Trabecular dysfunction is evident by the deposition of PEX material derived from both in situ and extra-trabecular production as well as protein and melanin deposition. These changes should be kept in mind by all intraocular surgeons as a source of potential difficulties in the perioperative period. Additionally, in light of these changes, patients need to be given realistic expectations regarding the increased risk of complications and more prolonged expected recovery time. In this short review, current reports relating to PEX pathological changes of practical interest to the intraocular surgeon are summarized.

Eye Lens Crystallins: A Component of Intraocular Pseudoexfoliative Material

Feeding experimental animals (19 pigs) with surplus sucrose and salt (NaCl) caused cataractous changes in lens tissue and triggered the formation of pseudoexfoliative material on the lens capsule. In the control animals (15 pigs) pseudoexfoliative material was absent. The avidin-biotin complex immunohistochemical method was applied to the pseudoexfoliative material obtained from 15 porcine experimental precataractous lenses and 1 spontaneously cataractous eye and revealed crystallins as a component of the intraocular pseudoexfoliative material. To prevent the development of both intraocular pseudoexfoliative material and crystallin-dependent glaucomatous changes in the trabecular meshwork of the eye, it is important to avoid any cataractogenic insult, including surplus sucrose and salt consumption, causing crystallin leakage from the lens.

Long anterior zonules and pigment dispersion

PURPOSE

To describe pigment dispersion associated with long anterior zonules.

DESIGN

Multicenter observational case series.

METHODS

Fifteen patients, seven of whom were treated for glaucoma or ocular hypertension, were identified with long anterior zonules and pigment dispersion. Transmission electron microscopy was performed on one anterior capsule specimen.

RESULTS

All patients had anterior zonules that inserted centrally on the lens capsule. Signs of pigment dispersion included corneal endothelial pigmentation, loss of the pupillary ruff, and variable trabecular meshwork pigmentation. Ultrasound biomicroscopy verified the lack of posterior iris insertion and concavity. There was no exfoliation material. Transmission electron microscopy showed zonular lamellae with adherent pigment granules, and no exfoliation material.

CONCLUSIONS

Long anterior zonules inserted onto the central lens capsule may cause mechanical disruption of the pigment epithelium at the pupillary ruff and central iris leading to pigment dispersion.

Plasma homocysteine is elevated in patients with exfoliation syndrome

PURPOSE

To compare plasma homocysteine concentrations among patients with exfoliation syndrome, exfoliative glaucoma, normal-tension glaucoma, and normal control subjects without vascular or inflammatory ocular disease or glaucoma.

DESIGN

Cross-sectional study.

METHODS

We tested 25 patients with exfoliation syndrome, 50 with exfoliative glaucoma, 25 with normal-tension glaucoma, and 24 control subjects. Fasting plasma homocysteine concentrations were measured by fluorescence polarization immunoassay. Patients using vitamin supplements or medications known to alter serum homocysteine were excluded.

RESULTS

Homocysteine levels were higher in both exfoliatin groups compared with controls (exfoliation syndrome: P =.003; exfoliative glaucoma: P =.009); levels in normal-tension glaucoma were higher than but not significantly different from those in controls (P =.2). Hyperhomocysteinemia was present in 16 of 25 (64%) exfoliation syndrome patients, 28 of 50 (56%) exfoliative glaucoma patients, 13 of 25 (52%) normal-tension glaucoma patients, and 7 of 24 (29.2%) controls (P =.005). Multiple logistic regression analyses comparing exfoliation syndrome and exfoliative glaucoma patients with controls indicated that elevated plasma homocysteine concentration was a significant risk factor for exfoliation syndrome, in both those patients (odds ratios per 1.0 micromol/l increase in plasma homocysteine concentrations = 1.47; 95% confidence interval [CI] = 1.08-2.0) and in exfoliative glaucoma patients (odds ratio = 1.3; 95% CI = 1.07-1.6). Although exfoliative glaucoma and normal-tension glaucoma patients were not significantly different with respect to hyperhomocysteinemia, logistic regression modeling of exfoliative glaucoma vs normal-tension glaucoma patients showed that an increased homocysteine concentration was a significant risk factor for exfoliation syndrome in the presence of glaucoma (odds ratio per 1.0 micromol/l increase in homocysteine = 1.2, 95% CI = 1.0-1.4). These relationships were not affected by adjustment for potential confounding due to sex, history of hypertension, or other factors.

RESULTS

Elevated plasma homocysteine, a risk factor for cardiovascular disease, is more common in exfoliation syndrome and exfoliative glaucoma patients than healthy controls. Patients with exfoliation syndrome may benefit from measurement of homocysteine levels.

Age-dependent iris abnormalities in collagen XVIII/endostatin deficient mice with similarities to human pigment dispersion syndrome

PURPOSE

Collagen XVIII is expressed in ocular basement membranes (BMs) and inactivating mutations cause Knobloch syndrome, with several ocular abnormalities. In this study we investigated ocular structures in collagen XVIII/endostatin (Col18a1(-/-))-deficient mice to elucidate the role of this extracellular matrix component in the eye.

METHODS

Eyes of Col18a1(-/-) and control mice were examined by light and transmission electron microscopy, laser scanning ophthalmoscopy, and fluorescence angiography. Immunohistochemical analysis of neuronal, epithelial, and immune cells in the eye was performed with antibodies against established cell markers.

RESULTS

Col18a1(-/-) mice showed a disruption of the posterior iris pigment epithelial (IPE) cell layer with release of melanin granules. The BM of the posterior IPE was attached to the lens and the nonpigmented epithelium of the ciliary body, which was flattened in mutant mice. In aged mutant mice a severe thickening of the stromal iris BM zone was found, and pigmented cells migrated out of the iris and covered the retina along the inner limiting membrane (ILM), sometimes penetrating into the retina. These cells resembled iris clump cells, and immunohistochemistry demonstrated that they were macrophage-like cells. Furthermore, morphologically abnormal retinal vasculature was seen by fluorescence angiography.

CONCLUSIONS

The abnormalities in the iris and ciliary body of Col18a1(-/-) mice demonstrate an important role of collagen XVIII for the function of ocular BMs. The absence of this collagen alters the properties of BMs and leads to severe defects in the iris, showing striking similarities to human pigment dispersion syndrome. In addition, loss of collagen XVIII creates changes that allow clump cells to migrate out of the iris. These cells have not been well characterized previously. In the current study we showed that they are macrophage-like cells and are able to penetrate the ILM in mutant mice. The disease mechanism of human pigment dispersion syndrome is not well understood, but Col18a1(-/-) mice may serve as a model and demonstrate the potential importance of alterations in extracellular matrix components in this disease.