Dispersion Syndrome Research Articles

Pigment dispersion syndrome – A unique presentation with extensive retina pigment deposition

Aims/Purpose: To report a unique presentation of pigment dispersion syndrome (PDS).Methods: Observational case report.Results: An 81‐year‐old woman presented to our department for a routine appointment. Relevant ophthalmologic history comprised prior bilateral cataract surgery in 2009 with single piece in‐the‐bag intraocular lens (IOL) implantation in right eye (RE) and sulcus implantation in the left eye (LE), due to capsular rupture. Upon examination, best corrected visual acuity was 10/10 in OD and OS. Intra‐ocular pressure (IOP) was 9/9 mmHg; there was anisocoria, with OS > OD in photopic conditions. OS slit lamp examination showed IOL positioned in the sulcus, diffuse pigment deposition in the corneal endothelium and uneven extensive 360° iris transillumination defects. Gonioscopy revealed extensive angle pigment deposition in OS; colour fundus photographs displayed extensive retina pigment deposition, mainly in the peripapillary and perivascular areas. No glaucomatous cupping of the optic disc was observed. A diagnosis of left PDS was entertained; given the lack of vision complains, normal visual acuity, IOP, and no glaucomatous damage of the optic nerve, close monitoring of the patient was undertaken.Conclusions: Pigment dispersion syndrome may arise from the iatrogenic damage to the iris of a single piece sulcus‐placed IOL and typically presents with extensive pigment deposition in the structures of the anterior segment, along with iris transillumination defects. To our knowledge, this is the second report of PDS with pigment deposition in the posterior segment. Indeed, although rare, convection currents may carry pigment to the vitreous and retina, which justifies the unusual findings in this patient and warrants a complete ophthalmologic evaluation in such cases.

Pigment dispersion syndrome: a unique presentation with extensive retina pigment deposition

Pigment dispersion syndrome: a unique presentation with extensive retina pigment deposition

A pigment dispersion syndrome case with concave iris and ocular hypertension managed through a phakic ICL implantation.

A concave iris configuration is a characteristic feature of pigment dispersion syndrome (PDS). Therapeutic strategies to modify this configuration may be considered as first-line options for the treatment of ocular hypertension in PDS patients. A 37-year-old male patient with myopic anisometropia presented bilateral PDS with concave iris, Krukenberg's spindle and iris transillumination defect in both eyes. The intraocular pressure (IOP) was 27 mmHg in both eyes. Optic nerve and visual field parameters were normal. The right eye was treated with a neodymium:YAG LPI. In the left eye, an implantable collamer lens (ICL) V4c model implantation for myopia correction was performed. Six-months postoperatively, both eyes evidenced an anteriorization of the iris, the morphology of the concave iris improved with the ICL V4c in place, becaming flattener in left eye. The IOP was 18 mmHg without treatment. This case report reinforces the idea that in myopic patients with a concave iris, the refractive correction approach through ICL V4c implantation might also improve the iris configuration, similarly to laser peripheral iridotomy (LPI). Therefore, in this specific patient profile, this surgical procedure might be considered as a prophylactic treatment alternative to prevent the complications associated with this iris configuration, although its invasive nature should be taken into consideration.

Overlap syndrome: a case series and literature review of concurrent pigment dispersion and pseudoexfoliation syndromes.

The purpose of this review is to present two cases of overlap syndrome, or concurrent pigment dispersion syndrome and pseudoexfoliation syndrome. The summary of existing literature highlights the importance of accurate diagnosis and potential treatment options of overlap syndrome. The cases describe two patients with overlap syndrome and resulting progressive glaucoma. The condition tends to present after age 50 years old, with presence of both pseudoexfoliative material and pigment dispersion signs. The pigment dispersion syndrome may be quiescent at the time of pseudoexfoliation onset and may have gone undiagnosed. This form of glaucoma poses challenges in controlling intraocular pressure and may progress rapidly, often requiring surgical intervention. This paper reviews the common examination findings of pigment dispersion syndrome and pseudoexfoliation, which may aid clinicians in the diagnosis of the rare condition, overlap syndrome. The connection between the two conditions remains unclear, though studies of possible genetic associations are underway. The two-hit theory, or initial damage to the trabecular meshwork increasing susceptibility to future damage, is plausible given the severe nature of the condition. Though definitive conclusions regarding treatment strategies and outcomes of overlap syndrome are lacking, increased awareness, diagnosis, and study of the condition may help guide the management of overlap syndrome.

METTL23 Variants and Patients With Normal-Tension Glaucoma

This research confirms and further establishes that pathogenic variants in a fourth gene, METTL23, are associated with autosomal dominant normal-tension glaucoma (NTG). To determine the frequency of glaucoma-causing pathogenic variants in the METTL23 gene in a cohort of patients with NTG from Iowa. This case-control study took place at a single tertiary care center in Iowa from January 1997 to January 2024, with analysis occurring between January 2023 and January 2024. Two groups of participants were enrolled from the University of Iowa clinics: 331 patients with NTG and 362 control individuals without glaucoma. Patients with a history of trauma; steroid use; stigmata of pigment dispersion syndrome; exfoliation syndrome; or pathogenic variants in MYOC, TBK1, or OPTN were also excluded. Detection of an enrichment of METTL23 pathogenic variants in individuals with NTG compared with control individuals without glaucoma. The study included 331 patients with NTG (mean [SD] age, 68.0 [11.7] years; 228 [68.9%] female and 103 [31.1%] male) and 362 control individuals without glaucoma (mean [SD] age, 64.5 [12.6] years; 207 [57.2%] female and 155 [42.8%] male). There were 5 detected instances of 4 unique METTL23 pathogenic variants in patients with NTG. Three METTL23 variants-p.Ala7Val, p.Pro22Arg, and p.Arg63Trp-were judged to be likely pathogenic and were detected in 3 patients (0.91%) with NTG. However, when all detected variants were evaluated with either mutation burden analysis or logistic regression, their frequency was not statistically higher in individuals with NTG than in control individuals without glaucoma (1.5% vs 2.5%; P = .27). This investigation provides evidence that pathogenic variants in METTL23 are associated with NTG. Within an NTG cohort at a tertiary care center, pathogenic variants were associated with approximately 1% of NTG cases, a frequency similar to that of other known normal-tension glaucoma genes, including optineurin (OPTN), TANK-binding kinase 1 (TBK1), and myocilin (MYOC). The findings suggest that METTL23 pathogenic variants are likely involved in a biologic pathway that is associated with glaucoma that occurs at lower intraocular pressures.

PHYTOSOCIOLOGICAL CHARACTERIZATION OF AN URBAN FRAGMENT OF INTERIOR ATLANTIC FOREST - PARANÁ, BRAZIL

The Parque Natural Municipal Paulo Gorski, located in western Paraná, comprises an urban remnant of Mixed Ombrophilous Forest. This study aimed to identify tree species and conduct the phytosociological characterization of this fragment of the Atlantic Forest. Monthly visits were made in ten plots (20 x 5 m) to collect fertile samples. A rarefaction curve was generated, and phytosociological parameters, diversity, and the distribution of individuals in diameter classes were calculated. A total of 158 tree individuals were sampled, distributed across 23 families and 47 species (including six exotic ones). Among the species found, 74.4% exhibited zoochoric dispersion syndrome, 19.1% anemochoric, and 6.5% autocoric. Concerning successional category, 63.8% were early successional species. Alchornea triplinervia (Spreng.) Müll.Arg. and Prunus myrtifolia (L.) Urb. had the highest importance values due to their high number of individuals, greater frequency, and basal area. Araucaria angustifolia (Bertol.) Kuntz, an endangered species, also had a high importance value. The Shannon diversity index was 3.43, and evenness was 0.89. Approximately 70% of the individuals were distributed in smaller diameter classes (< 15 cm), forming an inverted J-shape, an expected pattern indicating a regenerative capacity and structure of preserved forest remnants, despite being in an urban area and facing significant human pressures. This urban forest fragment should be preserved, as it contains native and endangered tree species from the region, serving as an ecological corridor, and maintains important ecological and social functions for the region.

Zentmayer line in pigment dispersion syndrome

Zentmayer line in pigment dispersion syndrome

Pigmentary glaucoma – a case report

Pigmentary glaucoma is a type of secondary open-angle glaucoma. Mainly it is a consequence of pigment dispersion syndrome, which is characterized by pigment accumulation in the anterior segment of the eye. Pigment in the trabecular meshwork can cause increased intraocular pressure leading to glaucomatous damage of the optic nerve. We present a case of 40-year-old myopic male with typical symptoms of pigmentary dispersion syndrome who received late diagnosis of the disease. The correct diagnosis of pigmentary dispersion syndrome is crucial in preventing glaucomatous vision impairment.

Harnessing Standing Sound Waves to Treat Intraocular Blood Cell Accumulation.

Certain ocular conditions result from the non-physiological presence of intraocular particles, leading to visual impairment and potential long-term damage. This happens when the normally clear aqueous humor becomes less transparent, thus blocking the visual axis and by intraocular pressure elevation due to blockage of the trabecular meshwork, as seen in secondary open-angle glaucoma (SOAG). Some of these "particle-related pathologies" acquire ocular conditions like pigment dispersion syndrome, pseodoexfoliation and uveitis. Others are trauma-related, such as blood cell accumulation in hyphema. While medical and surgical treatments exist for SOAG, there is a notable absence of effective preventive measures. Consequently, the prevailing clinical approach predominantly adopts a "wait and see" strategy, wherein the focus lies on managing secondary complications and offers no treatment options for particulate matter disposal. We developed a new technique utilizing standing acoustic waves to trap and direct intraocular particles. By employing acoustic trapping at nodal regions and controlled movement of the acoustic transducer, we successfully directed these particles to specific locations within the angle. Here, we demonstrate control and movement of polystyrene (PS) particles to specific locations within an in vitro eye model, as well as blood cells in porcine eyes (ex vivo). The removal of particles from certain areas can facilitate the outflow of aqueous humor (AH) and help maintain optimal intraocular pressure (IOP) levels, resulting in a non-invasive tool for preventing secondary glaucoma. Furthermore, by controlling the location of trapped particles we can hasten the clearance of the AH and improve visual acuity and quality more effectively. This study represents a significant step towards the practical application of our technique in clinical use.

Glaucoma secondary to cosmetic iris implants in congenital iris coloboma

Introduction: To report a case of angle closure and corneal decompensation requiring surgical intervention secondary to BrightOcular cosmetic iris implantation in a patient with a history of congenital bilateral iris coloboma. Patient and Clinical Findings: A 40-year-old male patient with a history of bilateral congenital coloboma presented to the emergency department with reduced visual acuity to count fingers and moderate pain in the left eye 4 months after bilateral BrightOcular iris implant surgery in Mexico. Intraocular pressure (IOP) was 70 mm Hg with little response to maximal medical therapy. Gonioscopy revealed dense pigment obstructing angle inferiorly. Diagnosis, Interventions, and Outcomes: The patient was diagnosed with angle closure, pigment dispersion syndrome, and corneal decompensation secondary to bilateral cosmetic iris implants. IOP stabilized after emergency Ahmed valve and Baerveldt shunt placement. Corneal decompensation addressed first with endothelial keratoplasty, however ultimately failed leading to penetrating keratoplasty in the left eye. Fellow eye required glaucoma shunt placement 4 years after initial presentation due to persistent glaucoma not controlled with laser and medical therapy. Conclusions: The use of iris implants for cosmetic reasons can have serious ocular morbidity in patients with iris coloboma. Close monitoring and explantation should be strongly recommended at the earliest sign of complication.

Exploring the Distinct Characteristic of Two Procedures for Sulcus Implementation following Posterior Capsular Rupture during Phacoemulsification: Single-piece Foldable IOLs and Polymethylmethacrylate IOLs

Introduction : Posterior capsular rupture (PCR) is one of the most feared complications of phacoemulsification. In? the?bag implantation of the lens becomes difficult if the PCR was large. Implantation of rigid polymethylmethacrylate (PMMA) or single?piece foldable IOL is implanted in the sulcus
 Case Illustration : After noting the PCR on both patients, single?piece foldable IOL of the same power was implanted in the ciliary sulcus. Same action was implemented to PMMA IOLs by enlarging the main port twice. Intracameral pilocarpine was injected and vitrectomy anterior was performed. The wound was closed with hydration on single-piece foldable IOL, meanwhile on PMMA IOLs, one hecting is required in the middle of mainport wound. The postoperative VA on day 1 from 0.12 on single-piece foldable IOLs and 0.25 on PMMA IOLs. Corneal edema, increased anterior chamber reaction was seen on single-piece foldable IOLs. Raised IOP was not found on both patients
 Discussion : Complications implantation single?piece foldable IOLs such as pigment dispersion syndrome, increased IOP. A surgical peripheral iridectomy can be created as a solution. Complication less likely occurred on the patient with longer axial length. The AL on this patient is AL 23.33 mm (single?piece foldable IOLs) and 24.08 mm (PMMA IOLs). The weakness of single piece foldable acrylic lenses are poor choice for ciliary sulcus placement and PMMA IOLs can induce astigmatism.
 Conclusion : Single-piece foldable IOLs are not designed for sulcus implantation. PMMA IOLs implantation can induce astigmatism.

Causes and management strategies for elevated intraocular pressure after implantable collamer lens implantation.

With the widespread application of Implantable Collamer Lens (ICL) implantation surgery in the field of myopia correction, a comprehensive understanding of its potential complications, especially those related to intraocular pressure (IOP), becomes crucial. This article systematically reviews various complications that may lead to IOP elevation after ICL surgery. Firstly, common complications after ICL surgery, including residual viscoelastic, steroid response, and excessive vault of the ICL, are detailed, emphasizing their potential impact on intraocular pressure. Regarding residual viscoelastic, we delve into its direct relationship with postoperative elevated IOP and possible preventive measures. For steroid response, we stress the importance of timely adjustment of steroid therapy and monitoring intraocular pressure. Additionally, excessive vault of the ICL is considered a significant potential issue, and we elaborate on its mechanism and possible management methods. In further discussion, we focus on relatively rare complications such as Toxic Anterior Segment Syndrome (TASS), Urrets-Zavalia Syndrome (UZS), Pigment Dispersion Syndrome (PDS), and malignant glaucoma. For these relatively rare complications, this review thoroughly explores their potential mechanisms, emphasizes the importance of prevention, and provides guidance for early diagnosis and treatment. This is a comprehensible review that aims to offer eye care professionals a comprehensive understanding and effective management guidance for complications of elevated IOP after ICL surgery, ultimately providing optimal care for patients' visual health.

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.

Pigment deposits in the retrolental space of Berger: a rare feature of pigment dispersion syndrome?

Pigment deposits in the retrolental space of Berger: a rare feature of pigment dispersion syndrome?

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.

Analysis of Lipoprotein Signaling in Iris Melanocytes.

Lipids are compounds involved in many biologic functions including cell structure, metabolism, energy storage and are involved in signaling. A prominent lipid in these functions is cholesterol. Cholesterol also plays a part in the signaling of melanocytes, which contain melanosomes. The maturation of these melanosomes happens during melanocyte growth. The deficit of melanogenesis or melanosome maturation is associated with ocular albinism in the eye. Aberrations of melanosome maturation are also associated with pigment dispersion syndrome. Albinism and pigment dispersion manifestations are systemic. Both melanogenesis and melanocyte maturation are affected by cholesterol metabolism. Cholesterol signaling is a part of many pathways in the body, and evaluating these signals can have implications in systemic disease processes of melanogenesis and melanosome maturation, like ocular albinism and pigment dispersion. Cholesterol is carried by lipoprotein particles. Low-density lipoprotein (LDL) is usually the transport vehicle for cholesterol to reach tissues and organelles. The LDL uptake on cells often sends out a cascade of internal signaling within the cells. We describe here LDL signaling related to lipase activity changes using enzymatic methods with a kit. We describe analyses of cholesterol esters and free cholesterol with liquid chromatography and gas chromatography with or in tandem with mass spectrometry (GC-MS and LC-MS/MS). These analyses will provide insight into melanosome maturation and melanogenesis. The methods described here are applicable to all melanocytes within the body of a model mammalian organism.

Multiple use of Shrubble-Arboreaal Species of a Cerrado Fragment, Northern Region of the Legal Amazon

Objective: This research aimed to evaluate the floristic composition and the potential of shrub-tree species in a fragment of cerrado sensu stricto, in the northern region of the Legal Amazon. Method: In an area of ​​Cerrado sensu stricto, the inventory was carried out using the fixed area sampling method. With this, all shrub-tree species with a diameter ≥ 10 cm were measured and phytosociological analyses, dyspesion syndrome and diameter distribution were determined. Result and Conclusion: According to the variables analyzed, it was possible to observe the establishment of new individuals in the diameter classes of 1 to 8.1 cm and 8.2 to 16.3 cm, therefore it can be seen that the species are part of the same ecological groups, that is, early and late, thus indicating high regenerative value due to the high entry of individuals, which allows a favorable ascension to mature successional stages. Researchimplications: Research related to phytosociological studies, dispersion syndrome and diametric distribution of shrub-arboreal species is of utmost importance to assess the diversity of Cerrado areas, mainly given the fact that it is the biome that is most currently being suppressed. Originality/value: The potential for using the Cerrado's phytodiversity is extremely important and due to agricultural development, species may disappear, in this way, the aim is to increase the level of knowledge of Cerrado species. With this, determine the timber and non-timber potential, in addition to relating dispersal syndromes and diameter distribution, in order to characterize the regenerative potential of these species.

Strategy of Surgical Treatment of Patients with Pigment Dispersion Syndrome and Myopia

Purpose: to conduct a prospective study of the results of surgical treatment of patients with pigment dispersion syndrome and complex myopic astigmatism. Materials and methods. As a result of a comprehensive examination of 10453 adult primary patients with complex myopic astigmatism, the diagnosis of pigment dispersion syndrome was made in 99 patients (0.94 %). The study group consisted of 22 people, 9 men and 13 women, with an average age of 29.4 ± 9.8. In the case of iridosonular contact, according to ultrasound biomicroscopy, laser basal iridectomy was performed at the first stage. In the case of normal intraocular pressure indicators, laser correction of myopia was made in patients of the study group within 6 months after laser basal iridectomy. Results. During biomicroscopy, a Krukenberg spindle was observed in 34 eyes (77.2 %), exogenous pigment was detected in 20 eyes (45.4 %) on the iris and lens, and sectoral illumination of the iris was detected in 5 (11.4 %). After laser basal iridectomy on 24 eyes (54.5 %) in all the studied meridians, we noted a tendency to deepen the posterior chamber, but the increase was statistically significant only at 12 hours (P &lt; 0.05). The achieved decrease in the angle of the anterior chamber was statistically significant (P &lt; 0.05) in the meridians of 3, 9 and 12 hours and ranged from 3.56 to 8.53 degrees in different meridians. Laser correction of complex myopic astigmatism was performed in 11 patients (22 eyes) using ReLEx® SMILE technology and 10 (20 eyes) patients using FemtoLASIK technology. At the end of the observation period after correction, refraction within ±0.5 dptr of the planned one was achieved in 88.1 % of cases (37 eyes), ±1.0 dptr — in 100 % of cases. The efficiency coefficient was 88.46 %, the safety coefficient was 92.8 %. Postoperative values of corneal-compensated IOP were comparable with preoperative indicators (P &gt; 0.05). Conclusions. The analysis of the of surgical treatment results in the patients with pigment dispersion syndrome and myopia showed the absence of negative dynamics in the course, as well as high efficiency, safety and stability of the results achieved after laser correction. The applied algorithm for the management of patients with combined pathology with pigment dispersion syndrome and myopia is pathogenetically justified, safe, promotes the preservation of visual functions of patients and improves their quality of life.

Appropriate patient population for future visual system axon regeneration therapies.

A number of blinding diseases caused by damage to the optic nerve result in progressive vision loss or loss of visual acuity. Secondary glaucoma results from traumatic injuries, pseudoexfoliation or pigmentary dispersion syndrome. Progressive peripheral vision loss is common to all secondary glaucoma irrespective of the initial event. Axon regeneration is a potential therapeutic avenue to restore lost vision in these patients. In contrast to the usual approach of having the worst possible patient population for initial therapies, axon regeneration may require consideration of appropriate patient population even for initial treatment trials. The current state of axon regeneration therapies, their potential future and suitable patient population when ready is discussed in this perspective. The selection of patients are important for adoption of axon regeneration specifically in the areas of central nervous system regenerative medicine. This article is categorized under: Neurological Diseases > Molecular and Cellular Physiology Neurological Diseases > Biomedical Engineering Metabolic Diseases > Molecular and Cellular Physiology.

Pseudovitelliform Macular Dystrophy and Pigment Dispersion Syndrome: Are They Related?

Pseudovitelliform macular dystrophy (PVMD) and pigment dispersion syndrome (PDS) are benign diseases that can evolve to a very severe stage. It is very rare to encounter both diseases in the same patient. We report a 42-year-old patient that presented a blurry vision. The anterior and posterior segment examination found pseudovitelliform macular degeneration associated with pigment dispersion syndrome. No other case was reported in the literature. The physiopathology and the location of the two diseases are very different. Both pathologies are frequently benign. A combination of them should be considered a risk for the patient. More cases of the two diseases should be reported to the literature if found and it could maybe lead to a link between them.