Pigment dispersion syndrome: a clinical study

XEN45 gel stent in the treatment of pigmentary glaucoma: A two-year follow-up

PURPOSE

To investigate safety and efficacy of the XEN gel stent in patients with pigmentary glaucoma (PG).

METHODS

A retrospective analysis of 26 eyes of 19 patients with PG undergoing XEN gel stent implantation was performed. Best-corrected visual acuity, intraocular pressure (IOP), and number of antiglaucoma medications were analyzed preoperatively, and at 2 weeks and 3, 6, 12, and 24 months after surgery. Success, needling, and complications were analyzed. Complete success was defined as an IOP reduction of >20% and achieving a target IOP of ≤18, ≤15, or ≤12 mmHg without antiglaucoma medication. Qualified success was indicated if the IOP target was reached with or without medication.

RESULTS

Mean IOP decreased significantly from 27.6 ± 14.3 (standard deviation, SD) mmHg to 14.3 ± 4.6 mmHg after one year (p < 0.001) and 15.1 ± 2.7 mmHg (p < 0.001) after two years. The median number of hypotensive drugs declined significantly from 4 (range: 3-5) to 0 (0-2) and 0 (0-3) after one and two years, respectively. After two years, complete success with an IOP of ≤18 mmHg and ≤15 mmHg was achieved in 73.1% and 61.5%, respectively. Half of the eyes required needling after a median time of 8 months (0.5-34 months). No sight-threatening complications were observed.

CONCLUSION

The XEN gel stent is a safe and effective surgical treatment option for PG. Needling is an important part of the procedure and should be communicated preoperatively to the patients.

Case report: Management of recurrent pupillary optic capture with sutureless surgical technique using 7-0 polypropylene flange

Background

To report a novel surgical technique for recurrent pupillary optic capture after flanged intraocular lens (IOL) fixation.

Methods

In this retrospective case series, we detail our use of two parallel 7-0 polypropylene sutures passed between the iris plane and the optic of scleral-fixated IOL to address pupillary optic capture. Flanges were created using ophthalmic cautery to secure it to the sclera without suture.

Results

Two eyes with pupillary optic capture underwent a sutureless surgical technique using 7-0 polypropylene flanges. No recurrences of pupillary optic capture were observed during the 1-year follow-up.

Conclusion

Our sutureless surgical technique using a 7-0 polypropylene flange was an effective, efficient, and less invasive approach for treating recurrent pupillary optic capture.

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.

Genetic Basis of Pigment Dispersion Syndrome and Pigmentary Glaucoma: An Update and Functional Insights

Pigment Dispersion Syndrome (PDS) and Pigmentary Glaucoma (PG) comprise a spectrum of ocular disorders characterized by iris pigment dispersion and trabecular meshwork changes, resulting in increased intraocular pressure and potential glaucomatous optic neuropathy. This review summarizes recent progress in PDS/PG genetics including rare pathogenic protein coding alterations (PMEL) and susceptibility loci identified from genome-wide association studies (GSAP and GRM5/TYR). Areas for future research are also identified, especially the development of efficient model systems. While substantial strides have been made in understanding the genetics of PDS/PG, our review identifies key gaps and outlines the future directions necessary for further advancing this important field of ocular genetics.

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.

Pigment dispersion syndrome and pigmentary glaucoma: overview and racial disparities

Pigment dispersion syndrome (PDS) and pigmentary glaucoma (PG) are two stages within the same ophthalmic disease spectrum, which are known to be affected by race. The prevalence of PDS is underestimated, largely due to its minor clinical symptoms. Although the prevalence of PG is low, the visual impairment associated with PG is extremely severe. The prevalence of PDS-PG is four or more times higher in Caucasians than in Blacks or Asians, and the "classic" PDS in Caucasians has long been used as a benchmark diagnostic criterion. Following extensive research focused on African Americans and Asians, the standard for diagnosing PDS-PG was refined. At the same time, the pathogenesis of PDS is not the same in different races. Hence, the effectiveness of preventive treatment and the need for treatment may not be equivalent in different races. The rate of conversion of PDS to PG is nearly 1/3 in Caucasians and higher in blacks and Asians, requiring more aggressive treatment and monitoring. We systematically searched a PubMed database from inception to March 2022 to provide an overview of research progress in various aspects of PDS-PG. Specifically, this paper considers the effects of race on disease prevalence, clinical manifestation, diagnostic criteria, disease mechanism, hereditary traits, treatment, and prevention to provide an accurate and comprehensive guide for the diagnosis and treatment of PDS-PG in various races.

One-Year Outcomes of Standalone XEN Gel Stent Versus Nonpenetrating Deep Sclerectomy

PRCIS

The nonpenetrating deep sclerectomy (NPDS) procedure resulted in significantly more surgical success than the standalone XEN gel stent procedure without differences in safety profile.

PURPOSE

The purpose of this study was to compare surgical success and safety profile of NPDS and XEN gel stent.

METHODS

A retrospective chart review of 328 eyes of 282 patients who were scheduled for standalone XEN gel stent surgery (n=140) or NPDS (n=188) at Groupe Hospitalier Paris Saint-Joseph between January 2017 and December 2018 was conducted. Primary outcome measure was the proportion of surgical success 12 months after surgery. Complete and qualified surgical successes were defined by intraocular pressure (IOP)≤18 mm Hg and a reduction of IOP≥20% without or with hypotensive medication, respectively.

RESULTS

In total, 82 eyes were included in the XEN group and 124 eyes in the NPDS group. In the 1-eye analysis, rates of "complete success" and "qualified success" were, respectively, at the end of follow-up, 28.57% and 20.00% in the XEN group, and 42.72% and 16.50% in the NPDS group ( P =0.17). Success probability plots based on the Kaplan-Meier estimate for overall surgical success demonstrated a median success probability time of 3.73 years for the NPDS group and 2.38 years for the XEN group ( P <0.0001). After adjustment for confounding variables using Cox regression, the NPDS procedure was significantly more associated with surgical success than the XEN gel stent implantation ( P <0.001). No difference was demonstrated in terms of reduction of antiglaucoma medications, needling procedures, or reoperations.

CONCLUSIONS

The NPDS procedure may be more effective than the XEN gel stent in reducing IOP in patients with open angle glaucoma and may result in longer surgical success. However, a well-conducted prospective randomized study is required to confirm these results.

Compound Heterozygous Variants of the CPAMD8 Gene Co-Segregating in Two Chinese Pedigrees With Pigment Dispersion Syndrome/Pigmentary Glaucoma

The molecular mechanisms underlying the pathogenesis of pigment dispersion syndrome and pigmentary glaucoma remain unclear. In pedigree-based studies, familial aggregation and recurrences in relatives suggest a strong genetic basis for pigmentary glaucoma. In this study, we aimed to identify the genetic background of two Chinese pedigrees with pigmentary glaucoma. All members of these two pedigrees who enrolled in the study underwent a comprehensive ophthalmologic examination, and genomic DNA was extracted from peripheral venous blood samples. Whole-exome sequencing and candidate gene verifications were performed to identify the disease-causing variants; in addition, screening of the CPAMD8 gene was performed on 38 patients of sporadic pigmentary glaucoma. Changes in the structure and function of abnormal proteins caused by gene variants were analyzed with a bioinformatics assessment. Pigmentary glaucoma was identified in a total of five patients from the two pedigrees, as were compound heterozygous variants of the CPAMD8 gene. No signs of pigmentary glaucoma were found in carriers of monoallelic CPAMD8 variant/variants. All four variants were inherited in an autosomal recessive mode. In addition to the 38 patients of sporadic pigmentary glaucoma, 13 variants of the CPAMD8 gene were identified in 11 patients. This study reported a possible association between CPAMD8 variants and pigment dispersion syndrome/pigmentary glaucoma.

Genome-Wide Association Study Identifies Two Common Loci Associated with Pigment Dispersion Syndrome/Pigmentary Glaucoma and Implicates Myopia in its Development

PURPOSE

To identify genetic variants associated with pigment dispersion syndrome (PDS) and pigmentary glaucoma (PG) in unrelated patients and to further understand the genetic and potentially causal relationships between PDS and associated risk factors.

DESIGN

A 2-stage genome-wide association meta-analysis with replication and subsequent in silico analyses including Mendelian randomization.

PARTICIPANTS

A total of 574 cases with PG or PDS and 52 627 controls of European descent.

METHODS

Genome-wide association analyses were performed in 4 cohorts and meta-analyzed in 3 stages: (1) a discovery meta-analysis was performed in 3 cohorts, (2) replication was performed in the fourth cohort, and (3) all 4 cohorts were meta-analyzed to increase statistical power. Two-sample Mendelian randomization was used to determine whether refractive error and intraocular pressure exert causal effects over PDS.

MAIN OUTCOME MEASURES

The association of genetic variants with PDS and whether myopia exerts causal effects over PDS.

RESULTS

Significant association was present at 2 novel loci for PDS/PG. These loci and follow-up analyses implicate the genes gamma secretase activator protein (GSAP) (lead single nucleotide polymorphism [SNP]: rs9641220, P = 6.0×10-10) and glutamate metabotropic receptor 5 (GRM5)/TYR (lead SNP: rs661177, P = 3.9×10-9) as important factors in disease risk. Mendelian randomization showed significant evidence that negative refractive error (myopia) exerts a direct causal effect over PDS (P = 8.86×10-7).

CONCLUSIONS

Common SNPs relating to the GSAP and GRM5/TYR genes are associated risk factors for the development of PDS and PG. Although myopia is a known risk factor, this study uses genetic data to demonstrate that myopia is, in part, a cause of PDS and PG.

Mechanism for altered dark-adapted electroretinogram responses in DBA/2J mice includes pupil dilation deficits

PURPOSE

The DBA/2J (D2) mouse is an established model of pigmentary glaucoma, a type of primary open angle glaucoma. Prior studies have documented defects in flash electroretinogram (ERG) responses in D2 mice, but the origin of those defects is not clear. The purpose of this study was to understand the origin of these A-wave and B-wave changes in D2 ERGs.Materials & Methods: To accomplish this, we analyzed the differences between 9-month-old DBA/2J-Gpnmb+ (D2-control) and D2 mouse eyes in relation to ERG responses, intraocular pressure (IOP), outer nuclear layer thickness, and pupil area.

RESULTS

D2 scotopic ERGs showed lower A-wave amplitude and longer implicit time as well as a significant rightward shift in the intensity-response curve. D2 IOP increased at approximately seven months of age and had a weak correlation with the ERG A-wave sensitivity. Outer nuclear layer thickness was not significantly different in D2s compared to D2-control retinas. D2 mouse pupils also showed abnormal pupillary shape and no dilation following treatment with tropicamide eye drops. The pupil size moderately correlated with the A-wave sensitivity and this was pharmacologically replicated in C57Bl/6J mice following administration of pilocarpine to constrict the pupils. However, pilocarpine treatment did not affect ERG amplitudes.

CONCLUSIONS

These data suggest that the smaller pupil sizes prevented light from reaching the photoreceptors and thus contributed to reduced ERG sensitivity in D2 mice. The reduced ERG A-wave amplitude in D2 mice likely results from dysfunctional photoreceptor responses.

[Pigmentary glaucoma: yesterday, today, tomorrow]

Pigment dispersion syndrome (PDS) is a condition that mostly affects young men with myopic refraction. PDS is characterized by the presence of Krukenberg spindle, peripheral iris defects, significant trabecular meshwork pigmentation, as well as convex iris configuration. Such configuration can cause friction of iris's posterior pigment layer on its ligaments, which leads to the release of pigment and its accumulation mostly in the structures of the anterior chamber. Over time PDS can progress into pigmentary glaucoma (PG), which in turn can lead to permanent loss of vision. This review analyzes available data on diagnosis and treatment of PDS and PG.

Gender Prediction for a Multiethnic Population via Deep Learning Across Different Retinal Fundus Photograph Fields: Retrospective Cross-sectional Study

Background

Deep learning algorithms have been built for the detection of systemic and eye diseases based on fundus photographs. The retina possesses features that can be affected by gender differences, and the extent to which these features are captured via photography differs depending on the retinal image field.

Objective

We aimed to compare deep learning algorithms’ performance in predicting gender based on different fields of fundus photographs (optic disc–centered, macula-centered, and peripheral fields).

Methods

This retrospective cross-sectional study included 172,170 fundus photographs of 9956 adults aged ≥40 years from the Singapore Epidemiology of Eye Diseases Study. Optic disc–centered, macula-centered, and peripheral field fundus images were included in this study as input data for a deep learning model for gender prediction. Performance was estimated at the individual level and image level. Receiver operating characteristic curves for binary classification were calculated.

Results

The deep learning algorithms predicted gender with an area under the receiver operating characteristic curve (AUC) of 0.94 at the individual level and an AUC of 0.87 at the image level. Across the three image field types, the best performance was seen when using optic disc–centered field images (younger subgroups: AUC=0.91; older subgroups: AUC=0.86), and algorithms that used peripheral field images had the lowest performance (younger subgroups: AUC=0.85; older subgroups: AUC=0.76). Across the three ethnic subgroups, algorithm performance was lowest in the Indian subgroup (AUC=0.88) compared to that in the Malay (AUC=0.91) and Chinese (AUC=0.91) subgroups when the algorithms were tested on optic disc–centered images. Algorithms’ performance in gender prediction at the image level was better in younger subgroups (aged <65 years; AUC=0.89) than in older subgroups (aged ≥65 years; AUC=0.82).

Conclusions

We confirmed that gender among the Asian population can be predicted with fundus photographs by using deep learning, and our algorithms’ performance in terms of gender prediction differed according to the field of fundus photographs, age subgroups, and ethnic groups. Our work provides a further understanding of using deep learning models for the prediction of gender-related diseases. Further validation of our findings is still needed.

Exome-based investigation of the genetic basis of human pigmentary glaucoma

Background

Glaucoma is a leading cause of visual disability and blindness. Release of iris pigment within the eye, pigment dispersion syndrome (PDS), can lead to one type of glaucoma known as pigmentary glaucoma. PDS has a genetic component, however, the genes involved with this condition are largely unknown. We sought to discover genes that cause PDS by testing cohorts of patients and controls for mutations using a tiered analysis of exome data.

Results

Our primary analysis evaluated melanosome-related genes that cause dispersion of iris pigment in mice (TYRP1, GPNMB, LYST, DCT, and MITF). We identified rare mutations, but they were not statistically enriched in PDS patients. Our secondary analyses examined PMEL (previously linked with PDS), MRAP, and 19 other genes. Four MRAP mutations were identified in PDS cases but not in controls (p = 0.016). Immunohistochemical analysis of human donor eyes revealed abundant MRAP protein in the iris, the source of pigment in PDS. However, analysis of MRAP in additional cohorts (415 cases and 1645 controls) did not support an association with PDS. We also did not confirm a link between PMEL and PDS in our cohorts due to lack of reported mutations and similar frequency of the variants in PDS patients as in control subjects.

Conclusions

We did not detect a statistical enrichment of mutations in melanosome-related genes in human PDS patients and we found conflicting data about the likely pathogenicity of MRAP mutations. PDS may have a complex genetic basis that is not easily unraveled with exome analyses.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-021-07782-0.

Pigment dispersion syndrome and its implications for glaucoma

Pigment dispersion syndrome (PDS) represents a clinical spectrum of a relatively common and usually underdiagnosed phenomenon produced by spontaneous pigment dispersion from the iris into the anterior segment. PDS is often bilateral, has no gender predisposition, and presents at a young age, particularly in myopes. Although most patients experiencing an episode of pigment dispersion are asymptomatic, extreme photophobia, ocular pain, redness, and blurred vision may occur. Other characteristic signs are iridolenticular contact, concave iris configuration, 360° peripheral iris transillumination, and pigment deposition on the anterior chamber angle or the corneal endothelium (Krukenberg spindle). Early PDS diagnosis is crucial to detect patients with pigment-related ocular hypertension (POHT) that can eventually lead to pigmentary glaucoma (PG). The latter represents a sight-threatening condition in which mechanical, environmental, and genetic factors contribute to optic nerve damage. In this review, we update the pathogenic mechanisms involved in the clinical spectrum of the disease. We describe its clinical presentation, ophthalmologic manifestations, and complications, including the factors influencing the development of POHT and PG. Because PDS has variable clinical presentations that lead to misdiagnoses, we emphasize the differential diagnosis and the actual therapeutic strategies according to disease status.

Canaloplasty in Pigmentary Glaucoma: Long-Term Outcomes and Proposal of a New Hypothesis on Its Intraocular Pressure Lowering Mechanism

This study presents the long-term results on canaloplasty in a group of patients affected by pigmentary glaucoma, and studies the progression of the disease after surgery. Material and methods: Twenty-nine eyes of 25 patients with pigmentary glaucoma in maximum tolerated medical therapy with significant visual field damage progression underwent canaloplasty and were followed up to 11 years (mean 59.8 ± 30.1 months). All patients underwent a complete ophthalmic examination every 6 months. Results: The pre-operative mean intraocular pressure (IOP) was 31.8 mmHg ± 10.9 (range 21–70) with an average of 3.3 medications. After 1, 2, 3, and 4 years, the mean IOP was 15.9 ± 4.0, 14.4 ± 7.3, 14.1 ± 2.1, and 15.7 mmHg, respectively, with 0.4, 0.5, and 0.7 medications, respectively. Four patients underwent trabeculectomy after 3 to 30 months due to uncontrolled IOP. Gonioscopy showed a significant reduction of pigment in trabecular meshwork in all cases, starting from the sixth month. In some cases, the pigment was almost completely reabsorbed after two years, suggesting an accelerated transit and escape of the granules through the trabecular spaces. Conclusions: Canaloplasty seems to be a reasonable option in treating patients affected by progressive pigmentary glaucoma. The reabsorption of pigment granules from the trabecular meshwork could, at least in part, explain the relatively high success rate observed after this surgical procedure.

A case of dense pigment deposition of the posterior lens capsule

BACKGROUND

Pigment dispersion syndrome (PDS) is a well-known entity which can lead to pigmentary glaucoma (PG). This case report presents a rare presentation of PG with bilateral dense pigment deposits of the posterior lens capsule.

CASE PRESENTATION

A 72-year-old male came for his first appointment due to an asymmetric worsening of visual acuity. The examination showed unilaterally severely increased intraocular pressure, bilateral dense pigment deposition of the posterior lens capsule, and a shallow unilateral optic disk excavation. Gonioscopy revealed moderate pigmentation of the angle and a concave configuration of the peripheral iris in both eyes. The standard slit lamp examination showed no transillumination defects of either iris. Optical coherence tomography showed retinal nerve fiber layer (RNFL) thinning in the peripapillary and macular regions. An antiglaucoma medication was prescribed with a good lowering effect.

CONCLUSION

Pigment deposition of the posterior lens capsule, which has been rarely reported, is a possible important sign of PDS or PG.

Genetic Heritability of Pigmentary Glaucoma and Associations With Other Eye Phenotypes

Importance

Mechanisms behind pigmentary glaucoma, a form of early-onset glaucoma that may potentially lead to severe visual impairment or blindness, are poorly understood.

Objective

To calculate the single-nucleotide polymorphism (SNP) heritability of pigmentary glaucoma and identify genetic associations with the disease.

Design, Setting and Participants

This genome-wide association study included affected individuals from Germany and control participants from the United Kingdom. Genome-wide information was obtained for patients with pigmentary glaucoma and control participants free of glaucoma by using the Illumina Human Omni Express Exome 8v1-2 chip and genomic imputation. The SNP heritability of pigmentary glaucoma was estimated through a restricted maximum likelihood analysis. Associations between the genetic variants and pigmentary glaucoma obtained from age, sex, and principal component-adjusted logistic regression models were compared with those of SNPs previously associated with other eye phenotypes using Pearson product-moment correlations. Data were collected from November 2008 to January 2018, and analysis was completed between April 2018 and August 2019.

Main Outcomes and Measures

An estimate of SNP-explained heritability for pigmentary glaucoma; correlations of effect sizes between pigmentary glaucoma and iris pigmentation and myopia; and correlations of effect sizes between pigmentary glaucoma and other eye phenotypes.

Results

A total of 227 affected individuals (mean [SD] age, 58.7 [13.3] years) and 291 control participants (mean [SD] age, 80.2 [4.9] years) were included; all were of European ancestry. The SNP heritability of pigmentary glaucoma was 0.45 (SE, 0.22; P = 6.15 × 10-10). Twelve SNPs previously reported with genome-wide significant associations with eye pigmentation were associated with pigmentary glaucoma's SNP heritability (4.9% SNP heritability; 0.022; P = 6.0 × 10-4). Pigmentary glaucoma SNP effect sizes were correlated moderately for myopia (r, 0.42 [95% CI, 0.14-0.63]; P = 4.3 × 10-3) and more strongly with those for iris pigmentation (r = -0.69 [95% CI, -0.91 to -0.20]; P = .01), although this was nonsignificant per a strict adjusted significance threshold (P < .01).

Conclusions and Relevance

These findings support the conclusion that pigmentary glaucoma may have a genetic basis and be highly heritable. Variants associated with lighter eye color and myopia appear to be associated with increased risk of pigmentary glaucoma, but no shared genetic basis with primary open-angle glaucoma (or its quantitative endophenotype of cup-disc ratio) was observed.

The Relationship Between Melanin and Glaucoma: A Case-control Study

PRéCIS:: In a case-control study, skin pigmentation was not statistically significantly different when comparing glaucoma patients to those without glaucoma.

PURPOSE

Darker skin color has been implicated as a risk factor for glaucoma based on previous studies' subjective assessments of skin pigmentation. This study used objective measurements to determine whether cutaneous pigmentation is a risk factor for glaucoma.

METHODS

This case-control study was conducted at Menelik II Tertiary Referral Hospital in Addis Ababa, Ethiopia. Patients aged 40 years or older from the glaucoma clinic who were being scheduled for trabeculectomy were enrolled as cases and age-matched patients without glaucoma from other clinics at Menelik II Tertiary Referral Hospital were enrolled as controls. A Dermacatch device was used to capture melanin measurements in triplicate from the inner arm of each participant. The exposure variable of interest was the median of the triplicate skin melanin measurements, in arbitrary units. The outcome of interest was presence of glaucoma.

RESULTS

Agreement between the triplicate inner arm melanin measurements was high, with an intraclass correlation of 0.99 (95% confidence interval, 0.98-0.99). Mean melanin values were 704 units (SD 94) in 76 cases and 694 units (SD 93) in 152 controls. Melanin was not statistically significantly associated with glaucoma after adjusting for sex and season of measurement (ie, dry vs. rainy), with an odds ratio of 1.15 (95% confidence interval, 0.59-2.24) per 100 units of inner arm melanin.

CONCLUSION

This study failed to find a significant association between skin pigmentation and glaucoma using an objective and reproducible assessment of pigmentation.

Prevalence of Pigment Dispersion Syndrome in Patients Seeking Refractive Surgery

PURPOSE

To determine the prevalence of pigment dispersion syndrome (PDS) in patients presenting for vision correcting refractive surgery.

SETTING

Discover Vision Centers, Kansas City, MO.

DESIGN

This is a prospective case series.

MATERIALS AND METHODS

A total of 637 eyes of 319 serial patients who presented seeking refractive surgery were included in this prospective, observational study. Patients underwent routine ophthalmologic examination before refractive surgery. PDS was diagnosed by the presence of a deep anterior chamber, posterior bowing of the irides, Krukenberg spindles, and/or presence of mid-peripheral iris transillumination defects by the same experienced ophthalmologist. The prevalence of PDS and its associated ophthalmic and demographic characteristics were evaluated in those diagnosed.

RESULTS

Of the 637 eyes, 165 (25.9%) eyes were diagnosed with PDS. Krukenberg spindles were present in 53 (8.3%) of the total eyes and in 47 (28.5%) eyes that were diagnosed with PDS. Transillumination defects were present in 153 (95%) eyes diagnosed with PDS and 161 (25.2%) total eyes. There was equal distribution between sex in those diagnosed with PDS (male vs. female: 26 vs. 25.8%; P=0.942). Blue colored eyes were most likely to have PDS (35.8% of patients).

CONCLUSIONS

The prevalence of PDS within the population of patients seeking refractive surgery is likely greater than the general population as a whole. This is most likely the result of self-selection and high association between myopia and PDS. Given that not infrequent sequela can occur from untreated PDS, it is prudent that refractive surgeons be aware of this increased prevalence and perform thorough examinations to properly identify the condition.

Pigment dispersion syndrome presenting as endothelial dystrophy: An atypical presentation

Purpose

To describe an atypical presentation of pigment dispersion syndrome (PDS) with diffuse, homogeneous pigment deposition on the corneal endothelium and its management.

Methods

A 44-year-old female was referred to a cornea clinic as a case of endothelial dystrophy. Slit-lamp examination revealed bilateral, diffuse, and homogeneous pigment deposition on entire corneal endothelium without any iris transillumination defects. Intraocular pressure (IOP) at presentation were 18 mmHg OD and 16 mmHg OS. Gonioscopy showed dense, homogeneous pigment deposition in the angles. The optic nerve head examination revealed a cup disc ratio of 0.6:1-0.7:1 in both eyes with neuroretinal rim thinning.

Results

Peripheral Nd:YAG laser peripheral iridotomy (PI) was performed. On follow-up, a localized clear pigment free endothelial area was noted over the iridotomy sites bilaterally. IOP was well controlled within 12-14 mmHg with prostaglandin analogue at last follow-up of 24 months.

Conclusions

Diffuse homogeneous pigment dispersion on the endothelium may occur in atypical cases of PDS which may clear in the areas overlying the PI site and, therefore, should not be confused with endothelial disease. This case demonstrates the significance of a thorough clinical evaluation in cases with unusual presentation.

The Heritability of Pigment Dispersion Syndrome and Pigmentary Glaucoma

PURPOSE

Pigment dispersion syndrome (PDS) and pigmentary glaucoma (PG) are presumed to be inherited in an autosomal dominant manner. We examine relatives of patients with PDS and PG in order to determine the heritability of these diseases.

DESIGN

This was a prospective, cross-sectional study.

METHODS

One hundred and one patients with PDS were prospectively recruited over 11 months. Four of the patients had PDS without ocular hypertension or glaucoma, 6 had PDS and ocular hypertension, and 91 had PG. Criteria for PDS were 2 of 3 signs: Krukenberg spindle, midperipheral iris transillumination defects, and/or heavy trabecular meshwork pigmentation. Criteria for PG were PDS and 2 of 3 signs: intraocular pressure >21 mm Hg, glaucomatous optic nerve damage, and/or glaucomatous visual field loss. Ninety-nine first-degree relatives living within a 100-mile radius of Iowa City, Iowa were examined in the clinic to determine the probability of familial transmission.

RESULTS

A total of 10 of 99 (10.10%) first-degree relatives were diagnosed with PDS (1 with PDS alone, 2 with PDS and ocular hypertension, and 7 with PG). Seven families with ≥2 affected members were identified. The majority of affected family members (8/10) showed moderate to heavy trabecular meshwork pigmentation and either Krukenberg spindle or transillumination defects.

CONCLUSIONS

Most of the cases of PDS in our study were sporadic, and the risk to first-degree relatives is lower than previously reported. However, there are families with apparent autosomal dominant inheritance of PDS in which the risk to relatives may be high.

Curvilinear, symmetrical, and profound pigment deposition on the posterior lens capsule in a patient with bilateral pigmentary dispersion syndrome

Introduction

The classic presentation of pigmentary dispersion syndrome (PDS) often consists of midperipheral iris transillumination defects, Krukenberg’s spindle, and dense homogeneous trabecular pigmentation. Other subtle, sometimes overlooked features include pigment on the lens zonules, pigment on the anterior lens capsule and pigment along the equator of the posterior lens capsule.

Case

This unique presentation of PDS presented with bilateral, dense, oblique, and symmetrical pigment deposition along the posterior lens capsule that changed in shape, density, and extent over the span of 3 years.

Discussion

There have been few reports in the literature that describe a central accumulation of pigment along the posterior lens capsule associated with PDS. There are reported cases of pigment deposition along the central aspect of the posterior lens capsule, some changing over time, although none were bilateral and symmetrical. There are suggestions that perhaps this central pigment deposition is related to a break in the ligament of Weiger, allowing communication between the posterior chamber and posterior lens capsule. This is a case in which curvilinear, symmetrical, and changing pigment deposition on the posterior lens capsule is suggestive of perhaps another key features of PDS.

Pigment dispersion syndrome and pigmentary glaucoma: a review and update

INTRODUCTION

Pigment dispersion syndrome (PDS) is a condition where anomalous iridozonular contact leads to pigment dispersion throughout the anterior segment and the released pigment is abnormally deposited on various ocular structures.

CLINICAL PRESENTATION

The clinical presentation of PDS is defined by the presence of pigmented cells on the corneal endothelium, an increase of pigmentation of the trabecular meshwork, and mid-periphery transillumination defects of the iris. This syndrome, more common in myopes, is usually bilateral and can be associated with ocular hypertension or glaucoma. Secondary open-angle pigmentary glaucoma (PG) can develop due to reduction of the outflow of aqueous humour and consequent increase in intraocular pressure leading to glaucomatous optic neuropathy. Diagnosis of PG is commonly between 40 and 50 years of age, occurring more frequently in men. The advent of ultrasound biomicroscopy and anterior segment optical coherence tomography has contributed to enhancing our knowledge on the condition. Typical alterations of the anterior segment are the posterior insertion of the iris and iris concavity. Treatment of PG should be initiated early to hinder disease progression, glaucomatous damage, and vision loss. Management is based on medical therapy, laser iridotomy, selective laser trabeculoplasty, and filtration procedures.

CONCLUSIONS

The differential diagnosis of PDS with other disorders can be challenging and awareness of the condition together with meticulous ophthalmologic examination allows early diagnosis followed by appropriate management strategies. The present review is a comprehensive report on the clinical characteristics, pathogenesis, current management, and status quo of PDS and PG.

Molecular Genetics of Pigment Dispersion Syndrome and Pigmentary Glaucoma: New Insights into Mechanisms

We explore the ideas and advances surrounding the genetic basis of pigment dispersion syndrome (PDS) and pigmentary glaucoma (PG). As PG is the leading cause of nontraumatic blindness in young adults and current tailored interventions have proven ineffective, a better understanding of the underlying causes of PDS, PG, and their relationship is essential. Despite PDS being a subclinical disease, a large proportion of patients progress to PG with associated vision loss. Decades of research have supported a genetic component both for PDS and conversion to PG. We review the body of evidence supporting a genetic basis in humans and animal models and reevaluate classical mechanisms of PDS/PG considering this new evidence.

Combined Phacoemulsification and Goniosynechialysis under an Endoscope for Chronic Primary Angle-Closure Glaucoma

Purpose

To investigate the clinical efficacy and safety of combined phacoemulsification with goniosynechialysis (GSL) under an ophthalmic endoscope for chronic primary angle-closure glaucoma and coexisting cataract.

Methods

This is a retrospective study. The intraocular pressure (IOP), best-corrected visual acuity (BCVA), and number of glaucoma medications at baseline and each postoperative follow-up visit were recorded. Other measurements included supraciliochoroidal fluid measured by anterior segment optical coherence tomography, corneal endothelial cell density (ECD), and peripheral anterior synechia (PAS). All patients were followed for more than a year.

Results

Thirty-eight eyes of 31 patients were included. The mean follow-up duration was 16.3 ± 3.9 months. The IOP decreased from 22.2 ± 9.3 mmHg at baseline to 15.4 ± 4.2 mmHg at the last follow-up (P < 0.001). The mean number of glaucoma medications (0.1 ± 0.6) at the last follow-up was significantly lower than the preoperative number (2.3 ± 1.1) (P < 0.001). All patients achieved improved or stable visual acuity after surgery. All patients achieved a complete opened angle after GSL. The postoperative complications included hyphema (7.9%), exudation (5.3%), transiently elevated IOP (55.3%), and supraciliochoroidal fluid (40%).

Conclusions

Combined phacoemulsification and GSL under an endoscope can completely reopen PAS and is an effective and safe method for patients with chronic primary angle-closure glaucoma and coexisting cataract.

Quantitative Assessment of Anterior Chamber Parameters in Pigmentary Glaucoma Using Slit-Lamp Optical Coherence Tomography

Purpose.

To quantitatively assess the parameters of anterior chamber and angle dimensions by slit-lamp optical coherence tomography (SL-OCT) in eyes with pigmentary glaucoma (PG).

Methods.

A total of 18 eyes of 11 patients with PG and 18 eyes of 11 healthy volunteers were included in the study. Anterior chamber depth (ACD), anterior chamber volume (ACV), spur distance (internal horizontal anterior chamber diameter), central corneal thickness (CCT), angle opening distance at 500 urn from the scleral spur (AOD 500), and trabecular iris space area at 500 μm from the scleral spur (TISA 500) parameters were detected by SL-OCT. The differences of anterior chamber parameters between patients with PG and the control group were analyzed by Mann-Whitney U test.

Results.

Mean ACD and ACV were measured as 3.28±0.38 mm and 191.6±39.7 mm3 respectively in the PG group. Mean AOD 500 and TISA 500 were 0.88±0.47 mm and 0.29±0.15 mm2 at the nasal angle and 1.14±0.67 mm and 0.41 ±0.23 mm2 at the temporal angle, respectively. Nasal and temporal angles were 49.83±11.1° and 53.83±10.46°. In eyes with PG, the midperipheral iris configuration was found to be considerably concave in 15 eyes (83.3%). Except CCT and spur distance, all anterior chamber dimension and angle parameters detected by SL-OCT were found to be significantly higher in the eyes with PG (Mann-Whitney U test, p<0.05).

Conclusions.

SL-OCT provided highly quantitative data on the parameters of anterior chamber and angle dimensions in PG. The evaluation of the anterior segment anatomy using SL-OCT revealed increased anterior chamber dimensions and posterior bowing of the iris consistent with the increase in angle parameters in patients with PG.

Update on pigment dispersion syndrome and pigmentary glaucoma

PURPOSE OF REVIEW

The present article reviews the clinical features and pathogenesis of pigment dispersion syndrome and pigmentary glaucoma and provides an update regarding their diagnosis and management.

RECENT FINDINGS

Newer imaging modalities including ultrasound biomicroscopy and anterior segment optical coherence tomography facilitate visualization of the iris concavity characteristic of eyes with pigment dispersion syndrome and pigmentary glaucoma. Patients with pigmentary glaucoma may be distinguished from those with other glaucoma types by the presence of typical symptoms, personality type, and patterns of diurnal intraocular pressure fluctuation. Although laser iridotomy has been shown to alter iris anatomy in pigmentary glaucoma, it is not proven to slow visual field progression. Multiple trials have validated the safety and efficacy of filtering surgery in treating pigmentary glaucoma, with fewer studies published on the role of micro-invasive glaucoma surgery.

SUMMARY

Literature from the review period has further defined the unique clinical characteristics of pigment dispersion syndrome and pigmentary glaucoma. Laser surgery has a limited role in the management of these entities, whereas trabeculectomy remains an acceptable first-line surgical treatment. Further studies are needed to define the potential application of the newer micro-invasive glaucoma procedures in pigmentary glaucoma.

Long-term Efficacy of Trabeculectomy on Chinese Patients with Pigmentary Glaucoma: A Prospective Case Series Observational Study

Background:

Though trabeculectomy is often performed on patients with medically refractive pigmentary glaucoma (PG), the clinical outcomes of surgical treatment on PG remain unknown. The aim of this study was to summarize the long-term efficacy and safety of trabeculectomy on PG.

Methods:

This was a prospective case series observational study. Eighteen consecutive PG patients were followed up for 8 years after trabeculectomy from May 2006 to April 2007. Visual acuity (VA), best-corrected visual acuity (BCVA), slit lamp biomicroscopy, intraocular pressure (IOP) measurement, Humphrey visual field analysis (VFA), and stereoscopic funduscopy were performed on admission and every 6 months after the surgery. Postoperative IOP, VA, BCVA, VFA, adjunctive anti-glaucoma medication, treatment-related side-effects, changes in blebs, and main clinical findings in the anterior segment of PG were recorded and compared with the baseline.

Results:

Eighteen PG eyes from 18 patients, with average preoperative IOP of 34.5 ± 4.7 mmHg (range: 21–47 mmHg, 1 mmHg=0.133 kPa) were enrolled in this study. All enrolled patients completed the follow-up visits and required examinations. Eight years after trabeculectomy, all surgical eyes (18/18) had satisfactory IOP control with an average of 13.7 ± 2.5 mmHg (range: 9–19 mmHg), which was significantly lower than baseline (P = 0.001). Majority (15/18) of the PG eyes had stable VA, BCVA, VFA, and optic disc cupping parameters. Functional blebs still existed in 12/18 of the PG eyes at the last follow-up visit. Unanimously, pigmentation in the anterior segment attenuated with time after surgical treatment. No severe side-effects were recorded in any of the surgical eyes.

Conclusions:

All surgical PG eyes in this study had satisfactory IOP control 8 years after the surgery with well-preserved visual function. The long-term efficacy and safety of trabeculectomy are promising in PG patients.

Peripheral iridotomy for pigmentary glaucoma

BACKGROUND

Glaucoma is a chronic optic neuropathy characterized by retinal ganglion cell death resulting in damage to the optic nerve head and the retinal nerve fiber layer. Pigment dispersion syndrome is characterized by a structural disturbance in the iris pigment epithelium (the densely pigmented posterior surface of the iris) that leads to dispersion of the pigment and its deposition on various structures within the eye. Pigmentary glaucoma is a specific form of open-angle glaucoma found in patients with pigment dispersion syndrome.Topcial medical therapy is usually the first-line treatment; however, peripheral laser iridotomy has been proposed as an alternate treatment. Peripheral laser iridotomy involves creating an opening in the iris tissue to allow drainage of fluid from the posterior chamber to the anterior chamber and vice versa. Equalizing the pressure within the eye may help to alleviate the friction that leads to pigment dispersion and prevent visual field deterioration. However, the effectiveness of peripheral laser iridotomy in reducing the development or progression of pigmentary glaucoma is unknown.

OBJECTIVES

The objective of this review was to assess the effects of peripheral laser iridotomy compared with other interventions, including medication, trabeculoplasty, and trabeculectomy, or no treatment, for pigment dispersion syndrome and pigmentary glaucoma.

SEARCH METHODS

We searched a number of electronic databases including CENTRAL, MEDLINE and EMBASE and clinical trials websites such as (mRCT) and ClinicalTrials.gov. We last searched the electronic databases on 2 November 2015.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) that had compared peripheral laser iridotomy versus no treatment or other treatments for pigment dispersion syndrome and pigmentary glaucoma.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures for systematic reviews. Two review authors independently screened articles for eligibility, extracted data, and assessed included trials for risk of bias. We did not perform a meta-analysis because of variability in reporting and follow-up intervals for primary and secondary outcomes of interest.

MAIN RESULTS

We included five RCTs (260 eyes of 195 participants) comparing yttrium-aluminum-garnet (YAG) laser iridotomy versus no laser iridotomy. Three trials included participants with pigmentary glaucoma at baseline, and two trials enrolled participants with pigment dispersion syndrome. Only two trials reported the country of enrollment: one - Italy, the other - United Kingdom. Overall, we assessed trials as having high or unclear risk of bias owing to incomplete or missing data and selective outcome reporting.Data on visual fields were available for one of three trials that included participants with pigmentary glaucoma at baseline. At an average follow-up of 28 months, the risk of progression of visual field damage was uncertain when comparing laser iridotomy with no iridotomy (risk ratio (RR) 1.00, 95% confidence interval (95% CI) 0.16 to 6.25; 32 eyes; very low-quality evidence). The two trials that enrolled participants with pigment dispersion syndrome at baseline reported the proportion of participants with onset of glaucomatous visual field changes during the study period. At three-year follow-up, one trial reported that the risk ratio for conversion to glaucoma was 2.72 (95% CI 0.76 to 9.68; 42 eyes; very low-quality evidence). At 10-year follow-up, the other trial reported that no eye showed visual field progression.One trial reported the mean change in intraocular pressure (IOP) in eyes with pigmentary glaucoma: At an average of nine months of follow-up, the mean difference in IOP between groups was 2.69 mmHg less in the laser iridotomy group than in the control group (95% CI -6.05 to 0.67; 14 eyes; very low-quality evidence). This trial also reported the mean change in anterior chamber depth at an average of nine months of follow-up and reported no meaningful differences between groups (mean difference 0.04 mm, 95% CI -0.07 to 0.15; 14 eyes; very low-quality evidence). No other trial reported mean change in anterior chamber depth. Two trials reported greater flattening of iris configuration in the laser iridotomy group than in the control group among eyes with pigmentary glaucoma; however, investigators provided insufficient data for analysis. No trial reported data related to mean visual acuity, aqueous melanin granules, costs, or quality of life outcomes.Two trials assessed the need for additional treatment for control of IOP. One trial that enrolled participants with pigmentary glaucoma reported that more eyes in the laser iridotomy group required additional treatment between six and 23 months of follow-up than eyes in the control group (RR 1.73, 95% CI 1.08 to 2.75; 46 eyes); however, the other trial enrolled participants with pigment dispersion syndrome and indicated that the difference between groups at three-year follow-up was uncertain (RR 0.91, 95% CI 0.38 to 2.17; 105 eyes). We graded the certainty of evidence for this outcome as very low.Two trials reported that no serious adverse events were observed in either group among eyes with pigment dispersion syndrome. Mild adverse events included postoperative inflammation; two participants required cataract surgery (at 18 and 34 months after baseline), and two participants required a repeat iridotomy.

AUTHORS' CONCLUSIONS

We found insufficient evidence of high quality on the effectiveness of peripheral iridotomy for pigmentary glaucoma or pigment dispersion syndrome. Although adverse events associated with peripheral iridotomy may be minimal, the long-term effects on visual function and other patient-important outcomes have not been established. Future research on this topic should focus on outcomes that are important to patients and the optimal timing of treatment in the disease process (eg, pigment dispersion syndrome with normal IOP, pigment dispersion syndrome with established ocular hypertension, pigmentary glaucoma).

Pigment Dispersion Syndrome Progression to Pigmentary Glaucoma in a Latin American Population

Objective: To determine the progression of pigment dispersion syndrome (PDS) into pigmentary glaucoma (PG) in a population at the Central Military Hospital in Bogotá, Colombia.

Materials and methods: A retrospective study was conducted, based on a review of medical records of patients with PDS evaluated in the Glaucoma Clinic. Data were collected in a database in excel and subsequently analyzed with the software Statistical Package for the Social Sciences (SPSS), performing Chi-square test analysis and Spearman’s rho test.

Results: Forty-eight eyes of 24 patients were included. Forty-two percent were women and 58% were men. Pigmentation of the trabecular meshwork was the most frequent clinical sign (100%), followed by Krukenberg’s spindle (91.7%), the least frequent were the iris concavity and iris heterochromia (4.2%), the average of the spherical equivalent was of - 1.33 (SD 2.07).

The rate of conversion of PDS to PG was 37.5%, after an average follow-up of 50.7 months. Having an intraocular pressure (IOP) greater than 21 mm Hg was statistically the only significant risk factor for conversion.

Conclusion: We found several differences in frequency and clinical signs in these patients in contrast to previous data, probably due to different racial characteristics.

The rate of progression is similar to previous reports despite of heterogeneity of these. Having IOP > 21 mm Hg was the only risk factor associated with progression in this sample.

How to cite this article: Gomez Goyeneche HF, Hernandez-Mendieta DP, Rodriguez DA, Sepulveda AI, Toledo JD. Pigment Dispersion Syndrome Progression to Pigmentary Glaucoma in a Latin American Population. J Curr Glaucoma Pract 2015;9(3):69-72.

Age-related eye disease and gender

Worldwide, the prevalence of moderate to severe visual impairment and blindness is 285 millions, with 65% of visually impaired and 82% of all blind people being 50 years and older. Meta-analyses have shown that two out of three blind people are women, a gender discrepancy that holds true for both developed and developing countries. Cataract accounts for more than half of all blindness globally and gender inequity in access to cataract surgery is the major cause of the higher prevalence of blindness in women. In addition to gender differences in cataract surgical coverage, population-based studies on the prevalence of lens opacities indicate that women have a higher risk of developing cataract. Laboratory as well as epidemiologic studies suggest that estrogen may confer antioxidative protection against cataractogenesis, but the withdrawal effect of estrogen in menopause leads to increased risk of cataract in women. For the other major age-related eye diseases; glaucoma, age-related macular degeneration (AMD) and diabetic retinopathy, data are inconclusive. Due to anatomic factors, angle closure glaucoma is more common in women, whereas the dominating glaucoma type; primary open-angle glaucoma (POAG), is more prevalent in men. Diabetic retinopathy also has a male predominance and vascular/circulatory factors have been implied both in diabetic retinopathy and in POAG. For AMD, data on gender differences are conflicting although some studies indicate increased prevalence of drusen and neovascular AMD in women. To conclude, both biologic and socioeconomic factors must be considered when investigating causes of gender differences in the prevalence of age-related eye disease.

Determining immune components necessary for progression of pigment dispersing disease to glaucoma in DBA/2J mice

Background

The molecular mechanisms causing pigment dispersion syndrome (PDS) and the pathway(s) by which it progresses to pigmentary glaucoma are not known. Mutations in two melanosomal protein genes (Tyrp1^b and Gpnmb^R150X) are responsible for pigment dispersing iris disease, which progresses to intraocular pressure (IOP) elevation and subsequent glaucoma in DBA/2J mice. Melanosomal defects along with ocular immune abnormalities play a role in the propagation of pigment dispersion and progression to IOP elevation. Here, we tested the role of specific immune components in the progression of the iris disease and high IOP.

Results

We tested the role of NK cells in disease etiology by genetically modifying the B6.D2-Gpnmb^R150XTyrp1^b strain, which develops the same iris disease as DBA/2J mice. Our findings demonstrate that neither diminishing NK mediated cytotoxic activity (Prf1 mutation) nor NK cell depletion (Il2rg mutation) has any influence on the severity or timing of Gpnmb^R150XTyrp1^b mediated iris disease. Since DBA/2J mice are deficient in CD94, an important immune modulator that often acts as an immune suppressor, we generated DBA/2J mice sufficient in CD94. Sufficiency of CD94 failed to alter either the iris disease or the subsequent IOP elevation. Additionally CD94 status had no detected effect on glaucomatous optic nerve damage.

Conclusion

Our previous data implicate immune components in the manifestation of pigment dispersion and/or IOP elevation in DBA/2J mice. The current study eliminates important immune components, specifically NK cells and CD94 deficiency, as critical in the progression of iris disease and glaucoma. This narrows the field of possible immune components responsible for disease progression.

An Overlap Syndrome of Pigment Dispersion and Pigmentary Glaucoma accompanied by Marfan Syndrome: Case Report with Literature Review

‘Overlap syndrome' describes the situation in which two or more ‘independent' conditions are present, either one of which could cause a particular finding. This current presentation reports a case with bilateral pigment dispersion syndrome (PDS), advanced pigmentary glaucoma (PG), and the Marfan syndrome, with bilateral subluxation of the lenses, and large short-term and long-term fluctuations of intraocular pressure. It is interesting to consider whether the associated advanced glaucomatous nerve damage could be a manifestation of just the PDS, just the Marfan syndrome, or rather a combination of these two overlapping independent conditions.

How to cite this article: Chakravarti T, George S. An Overlap Syndrome of Pigment Dispersion and Pigmentary Glaucoma accompanied by Marfan Syndrome: Case Report with Literature Review. J Current Glau Prac 2013;7(2):91-95.

The genetics of pigment dispersion syndrome and pigmentary glaucoma

We review the inheritance patterns and recent genetic advances in the study of pigment dispersion syndrome (PDS) and pigmentary glaucoma (PG). Both conditions may result from combinations of mutations in more than one gene or from common variants in many genes, each contributing small effects. We discuss the currently known genetic loci that may be related with PDS/PG in humans, the role of animal models in expanding our understanding of the genetic basis of PDS, the genetic factors underlying the risk for conversion from PDS to PG and the relationship between genetic and environmental--as well as anatomical--risk factors.

Sex- and gender-based differences in healthy and diseased eyes

PURPOSE

The aim of this study was to identify sex- and gender-based differences in ocular anatomy, physiology, and disease susceptibility or manifestation.

METHODS

Review of current indexed literature was conducted.

RESULTS

Sex and sex hormones influence the lacrimal system, eyelids and blinking, corneal anatomy and disease, aqueous humor dynamics and glaucoma, crystalline lens and cataract, uveitis and retinal disease, ocular circulation, and optic nerve anatomy and disease. Systemic conditions, particularly autoimmune disease, and conditions that are unique to women, such as pregnancy and menopause, further illustrate the effects of sex hormones on the eye. Gender-based differences in ocular conditions and disease should be considered within the context of the underlying physical and social environment.

CONCLUSIONS

Many sex- and gender-based differences exist in healthy and diseased eyes.