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Robert Ritch - One of the best experts on this subject based on the ideXlab platform.
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Pigment Dispersion Syndrome and Pigmentary Glaucoma
Clinical Glaucoma Care, 2013Co-Authors: Sung Chul Park, Celso Tello, Nathan M. Radcliffe, Robert RitchAbstract:Pigment Dispersion Syndrome (PDS) and Pigmentary glaucoma (PG) are two successive stages of the same disease process characterized by disruption of the posterior iris Pigment epithelium and deposition of the dispersed Pigment granules throughout the anterior segment. The classic diagnostic triad that characterizes the PDS consists of corneal endothelial Pigmentation; slit-like, radial, mid-peripheral iris transillumination defects; and dense homogeneous Pigmentation of the trabecular meshwork. In PDS, the anterior chamber is often deeper than normal both centrally and peripherally. The iridocorneal angle is typically wide open, the iris is inserted posteriorly into the ciliary body, and the configuration of the peripheral iris is concave1. PG is defined as glaucomatous optic neuropathy attributable to elevated intraocular pressure (IOP) from PDS.
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Pigment Dispersion Syndrome patients do not have larger-than-normal irides.
Journal of glaucoma, 2010Co-Authors: Elyse Trastman-caruso, Syril Dorairaj, Celso Tello, Jeffrey M. Liebmann, Victor H. Barocas, Robert RitchAbstract:PurposeTo compare iris cross-sectional area and thickness in the accommodated and unaccommodated states in controls versus patients with Pigment Dispersion Syndrome (PDS) and to quantify short-term response of the iris to accommodation.Patients and MethodsThirty-three patients with PDS and 17 contro
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Temporal evolution of intraocular pressure elevation after pupillary dilation in Pigment Dispersion Syndrome.
Journal of glaucoma, 2009Co-Authors: Daniel A. Jewelewicz, Jeffrey M. Liebmann, Nathan M. Radcliffe, Robert RitchAbstract:PURPOSE: To report 4 patients with Pigment Dispersion Syndrome (PDS) who had delayed intraocular pressure (IOP) spikes after pharmacologic pupillary dilation. METHODS: Four patients with a diagnosis of PDS with documented IOP spike after pharmacologic pupillary dilation were included. Study patients were examined before and after pupillary dilation. The amount of Pigment present in the anterior chamber and the IOP were measured at hourly intervals. RESULTS: Although maximal Pigment liberation occurred immediately after maximal dilation, the IOP continued to elevate for at least 1.5 hours. CONCLUSIONS: The increase in IOP after pupillary dilation may not occur simultaneously with maximal Pigment liberation but may follow it after the Pigment has settled out of the anterior chamber. This has implications for monitoring patients with PDS after dilation to detect and treat rises in IOP.
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Exfoliation Syndrome and exfoliation glaucoma-associated LOXL1 variations are not involved in Pigment Dispersion Syndrome and Pigmentary glaucoma.
Molecular vision, 2008Co-Authors: Kollu N. Rao, Syril Dorairaj, Jeffrey M. Liebmann, Robert Ritch, Inderjeet Kaur, Ravi Thomas, Subhabrata ChakrabartiAbstract:Purpose Single nucleotide polymorphisms (SNPs) in the LOXL1 gene have been implicated in exfoliation Syndrome (XFS) and exfoliation glaucoma (XFG). We have shown that these SNPs are not associated with the primary glaucomas such as primary open-angle (POAG) glaucoma and primary angle-closure glaucoma (PACG). To further establish the specificity of LOXL1 SNPs for XFS and XFG, we determined whether these SNPs were involved in Pigment Dispersion Syndrome (PDS) and Pigmentary glaucoma (PG).
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Ultrasound biomicroscopy in asymmetric Pigment Dispersion Syndrome and Pigmentary glaucoma
Archives of Ophthalmology, 2006Co-Authors: Fábio Nishimura Kanadani, Syril Dorairaj, Alan M Langlieb, Wisam A. Shihadeh, Celso Tello, Jeffrey M. Liebmann, Robert RitchAbstract:Objective: To identify differences in anterior chamber anatomy among patients with asymmetric Pigment Dispersion Syndrome and no other discernible cause for the asymmetry. Methods: Ultrasound biomicroscopy and A-scan biometry were performed on both eyes of 13 patients with asymmetric Pigment Dispersion Syndrome without a known cause for asymmetric involvement. A radial perpendicular image in the horizontal temporal meridian detailing the scleral spur, angle anatomy, and iris configuration was obtained for each eye by 2 examiners. Results: There were no differences in lens thickness (P=.33), refractive error (P=.84), or axial length (P=.99) between more and less affected eyes. However, the mean ± SD iris concavity (P.001), iris-lens contact distance (P=.02), and distance from the scleral spur to the iris insertion (0.42±0.11 vs 0.29±0.06 mm) (P=.002) were greater in the more affected eye of each patient. Conclusion: A more posterior iris insertion predisposes to the phenotypic expression of Pigment Dispersion Syndrome. Arch Ophthalmol. 2006;124:1573-1576
Jeffrey M. Liebmann - One of the best experts on this subject based on the ideXlab platform.
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Pigment Dispersion Syndrome patients do not have larger-than-normal irides.
Journal of glaucoma, 2010Co-Authors: Elyse Trastman-caruso, Syril Dorairaj, Celso Tello, Jeffrey M. Liebmann, Victor H. Barocas, Robert RitchAbstract:PurposeTo compare iris cross-sectional area and thickness in the accommodated and unaccommodated states in controls versus patients with Pigment Dispersion Syndrome (PDS) and to quantify short-term response of the iris to accommodation.Patients and MethodsThirty-three patients with PDS and 17 contro
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Temporal evolution of intraocular pressure elevation after pupillary dilation in Pigment Dispersion Syndrome.
Journal of glaucoma, 2009Co-Authors: Daniel A. Jewelewicz, Jeffrey M. Liebmann, Nathan M. Radcliffe, Robert RitchAbstract:PURPOSE: To report 4 patients with Pigment Dispersion Syndrome (PDS) who had delayed intraocular pressure (IOP) spikes after pharmacologic pupillary dilation. METHODS: Four patients with a diagnosis of PDS with documented IOP spike after pharmacologic pupillary dilation were included. Study patients were examined before and after pupillary dilation. The amount of Pigment present in the anterior chamber and the IOP were measured at hourly intervals. RESULTS: Although maximal Pigment liberation occurred immediately after maximal dilation, the IOP continued to elevate for at least 1.5 hours. CONCLUSIONS: The increase in IOP after pupillary dilation may not occur simultaneously with maximal Pigment liberation but may follow it after the Pigment has settled out of the anterior chamber. This has implications for monitoring patients with PDS after dilation to detect and treat rises in IOP.
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Exfoliation Syndrome and exfoliation glaucoma-associated LOXL1 variations are not involved in Pigment Dispersion Syndrome and Pigmentary glaucoma.
Molecular vision, 2008Co-Authors: Kollu N. Rao, Syril Dorairaj, Jeffrey M. Liebmann, Robert Ritch, Inderjeet Kaur, Ravi Thomas, Subhabrata ChakrabartiAbstract:Purpose Single nucleotide polymorphisms (SNPs) in the LOXL1 gene have been implicated in exfoliation Syndrome (XFS) and exfoliation glaucoma (XFG). We have shown that these SNPs are not associated with the primary glaucomas such as primary open-angle (POAG) glaucoma and primary angle-closure glaucoma (PACG). To further establish the specificity of LOXL1 SNPs for XFS and XFG, we determined whether these SNPs were involved in Pigment Dispersion Syndrome (PDS) and Pigmentary glaucoma (PG).
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Ultrasound biomicroscopy in asymmetric Pigment Dispersion Syndrome and Pigmentary glaucoma
Archives of Ophthalmology, 2006Co-Authors: Fábio Nishimura Kanadani, Syril Dorairaj, Alan M Langlieb, Wisam A. Shihadeh, Celso Tello, Jeffrey M. Liebmann, Robert RitchAbstract:Objective: To identify differences in anterior chamber anatomy among patients with asymmetric Pigment Dispersion Syndrome and no other discernible cause for the asymmetry. Methods: Ultrasound biomicroscopy and A-scan biometry were performed on both eyes of 13 patients with asymmetric Pigment Dispersion Syndrome without a known cause for asymmetric involvement. A radial perpendicular image in the horizontal temporal meridian detailing the scleral spur, angle anatomy, and iris configuration was obtained for each eye by 2 examiners. Results: There were no differences in lens thickness (P=.33), refractive error (P=.84), or axial length (P=.99) between more and less affected eyes. However, the mean ± SD iris concavity (P.001), iris-lens contact distance (P=.02), and distance from the scleral spur to the iris insertion (0.42±0.11 vs 0.29±0.06 mm) (P=.002) were greater in the more affected eye of each patient. Conclusion: A more posterior iris insertion predisposes to the phenotypic expression of Pigment Dispersion Syndrome. Arch Ophthalmol. 2006;124:1573-1576
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Retinal Pigment epithelial dysfunction in patients with Pigment Dispersion Syndrome: implications for the theory of pathogenesis.
Archives of ophthalmology (Chicago Ill. : 1960), 2001Co-Authors: Vivienne C. Greenstein, Jeffrey M. Liebmann, William Seiple, Robert RitchAbstract:Objective To test the hypothesis that the retinal Pigment epithelial/photoreceptor complex is affected in patients with Pigment Dispersion Syndrome and/or in patients with Pigmentary glaucoma. Methods Electro-oculograms were recorded from patients with Pigment Dispersion Syndrome, Pigmentary glaucoma, ocular hypertension, and primary open-angle glaucoma and from control subjects. Electro-oculograms were recorded during 15 minutes of dark adaptation followed by 15 minutes of light adaptation. For each subject, dark-trough amplitudes, dark-trough latencies, light-peak amplitudes, light-peak latencies, and ratios of the light-peak amplitude to the dark-trough amplitude (Arden ratios) were calculated. Results A 1-way analysis of variance of the Arden ratios indicated significant differences among the groups of subjects. Results of a post hoc Newman-Keuls test revealed that the mean Arden ratios of patients with Pigment Dispersion Syndrome and patients with Pigmentary glaucoma were significantly lower than the mean ratios of the controls, the patients with primary open-angle glaucoma, and those with ocular hypertension. Conclusions The results provide support for the hypothesis that the integrity of the retinal Pigment epithelial/photoreceptor complex is affected in patients with Pigment Dispersion Syndrome and in those with Pigmentary glaucoma. Congenital and/or structural abnormalities of the retinal Pigment epithelial/photoreceptor complex should be considered when models of the etiology of Pigment Dispersion Syndrome are proposed.
Onur Çatak - One of the best experts on this subject based on the ideXlab platform.
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Annular and central heavy Pigment deposition on the posterior lens capsule in the Pigment Dispersion Syndrome
International Ophthalmology, 2008Co-Authors: Burak Turgut, Peykan Türkçüoğlu, Nurettin Deniz, Onur ÇatakAbstract:Purpose To report annular and central heavy Pigment deposition on the posterior lens capsule in a case of Pigment Dispersion Syndrome. Methods Case report. Results A 36-year-old female with bilateral Pigment Dispersion Syndrome presented with progressive decrease in visual acuity in the right eye over the past 1–2 years. Clinical examination revealed the typical findings of Pigment Dispersion Syndrome including bilateral Krunkenberg spindles, iris transillumination defects, and dense trabecular meshwork Pigmentation. Remarkably, annular and central dense Pigmentation of the posterior lens capsule was noted in the right eye. Conclusion Annular Pigment deposition on the posterior lens capsule may be a rare finding associated with Pigment Dispersion Syndrome. Such a finding suggests that there may be aqueous flow into the retrolental space in some patients with this condition. The way of central Pigmentation is the entrance of aqueous to Berger’s space. In our case, it is probable that spontaneous detachment of the anterior hyaloid membrane aided this entrance.
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Annular and central heavy Pigment deposition on the posterior lens capsule in the Pigment Dispersion Syndrome: Pigment deposition on the posterior lens capsule in the Pigment Dispersion Syndrome.
International ophthalmology, 2007Co-Authors: Burak Turgut, Peykan Türkçüoğlu, Nurettin Deniz, Onur ÇatakAbstract:Purpose To report annular and central heavy Pigment deposition on the posterior lens capsule in a case of Pigment Dispersion Syndrome. Methods Case report. Results A 36-year-old female with bilateral Pigment Dispersion Syndrome presented with progressive decrease in visual acuity in the right eye over the past 1–2 years. Clinical examination revealed the typical findings of Pigment Dispersion Syndrome including bilateral Krunkenberg spindles, iris transillumination defects, and dense trabecular meshwork Pigmentation. Remarkably, annular and central dense Pigmentation of the posterior lens capsule was noted in the right eye. Conclusion Annular Pigment deposition on the posterior lens capsule may be a rare finding associated with Pigment Dispersion Syndrome. Such a finding suggests that there may be aqueous flow into the retrolental space in some patients with this condition. The way of central Pigmentation is the entrance of aqueous to Berger’s space. In our case, it is probable that spontaneous detachment of the anterior hyaloid membrane aided this entrance.
Björn Olsen - One of the best experts on this subject based on the ideXlab platform.
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Age-dependent iris abnormalities in collagen XVIII/endostatin deficient mice with similarities to human Pigment Dispersion Syndrome.
Investigative ophthalmology & visual science, 2003Co-Authors: Alexander G. Marneros, Björn OlsenAbstract: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 strictures 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 Co118a1 -/- mice may serve as a model and demonstrate the potential importance of alterations in extracellular matrix components in this disease.
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age dependent iris abnormalities in collagen xviii endostatin deficient mice with similarities to human Pigment Dispersion Syndrome
Investigative Ophthalmology & Visual Science, 2003Co-Authors: Alexander G. Marneros, Björn OlsenAbstract: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 strictures 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 Co118a1 -/- mice may serve as a model and demonstrate the potential importance of alterations in extracellular matrix components in this disease.
Gottfried O. H. Naumann - One of the best experts on this subject based on the ideXlab platform.
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Effect of neodymium:YAG laser iridotomy on number of aqueous melanin granules in primary Pigment Dispersion Syndrome
Graefe's Archive for Clinical and Experimental Ophthalmology, 2001Co-Authors: Michael Küchle, Christian Y. Mardin, Nhung X. Nguyen, Gottfried O. H. NaumannAbstract:Purpose : Increased numbers of aqueous melanin granules have been reproducibly demonstrated in eyes with Pigment Dispersion Syndrome using the cell count mode of the laser flare-cell meter. It was the aim of this study to measure the exact number of aqueous melanin granules in eyes with Pigment Dispersion Syndrome and Pigmentary glaucoma before and after Nd:YAG laser iridotomy. Methods : Nine eyes of seven patients with a clinical diagnosis of primary Pigment Dispersion Syndrome and secondary open-angle glaucoma (mean age 41.1±10.8 years) were included in this study. Aqueous cells were quantified using the cell count mode of the laser flare-cell meter (Kowa FC-1000) before and 30 min after medical pupillary dilation. Measurements were performed before and 15±7 weeks after Nd:YAG laser iridotomy. The main outcome measure was the number of aqueous melanin granules before and after Nd:YAG laser iridotomy. Results : The number (mean and quartiles) of aqueous melanin granules/0.075 µl aqueous humor (normal/dilated pupil) before antiglaucoma treatment was 4.5 (4.0, 7.25)/9.0 (5.0, 13.0) and was significantly reduced after iridotomy [1.5 (0.75, 3.25)/4.0 (1.6, 6.25), P =0.016]. Conclusion : Nd:YAG laser iridotomy results in significant (65%) decrease of aqueous melanin granules in eyes with primary Pigment Dispersion Syndrome. This finding appears to confirm the concept of reverse pupillary block in primary Pigment Dispersion Syndrome and may indicate that laser iridotomy is a useful treatment option in this condition.
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Quantification of aqueous melanin granules in primary Pigment Dispersion Syndrome
American Journal of Ophthalmology, 1998Co-Authors: Michael Küchle, Christian Y. Mardin, Nhung X. Nguyen, Peter Martus, Gottfried O. H. NaumannAbstract:Abstract PURPOSE Aqueous melanin granules are essential in the pathogenesis of Pigment Dispersion Syndrome and Pigmentary glaucoma. We quantified aqueous melanin granules with the laser flare-cell meter in patients with Pigment Dispersion Syndrome, assessed the measurement reproducibility, and correlated the numbers with clinical findings. METHODS Aqueous melanin granules were counted by means of the cell count mode of the laser flare-cell meter (KOWA FC-1000; Kowa, Tokyo, Japan) in 42 eyes of 21 patients with primary Pigment Dispersion Syndrome under three conditions (undilated pupils, dilated pupils, after exercise). The reproducibility of the measurements was determined with the intraclass correlation coefficient. A control group of 40 age- and sex-matched eyes was also examined after pupillary dilation. The results were correlated with biomicroscopic findings in eyes with Pigment Dispersion Syndrome (retrocorneal Krukenberg spindle, iris transillumination, Pigmentation of trabecular meshwork). RESULTS Numerous aqueous melanin granules were detected in eyes with Pigment Dispersion Syndrome (mean, 2.9 ± 3.7 granules/0.075 mm 3 ) but only small numbers were counted in normal eyes (0.2 ± 0.3, P P P > .5). The reproducibility of the measurements was very high (intraclass coefficient >0.92). The number of melanin granules correlated with the degree of Krukenberg spindle ( r = .61, P = .004) and with iris transillumination ( r = .69, P = .001). CONCLUSIONS Quantification of aqueous melanin granules yields reproducible results and shows increased numbers in Pigment Dispersion Syndrome, especially after pupillary dilation. Aqueous melanin granule quantification may be useful for evaluating eyes with Pigment Dispersion Syndrome and for assessing treatment effects.