Clinical Characteristics of Pigment Dispersion Syndrome (PDS) and Pigmentary Glaucoma (PG) Patients: A Cross-sectional Study from Eastern Uttar Pradesh

Introduction: Pigmentary Glaucoma (PG) and Pigment Dispersion Syndrome (PDS) are two different spectrums of a single disease. Since the disease is seen in younger population and is rapidly progressive blinding disease, therefore early diagnosis and treatment will reduce the burden of the disease and improve the quality of life. Aim: The aim of this study was to evaluate clinical characteristics of PDS and PG patients in eastern part of Uttar Pradesh. Materials and Methods: This was a two years (1st January 2018 to 31st December 2019) hospital-based retrospective cross-sectional study of patients who attended the glaucoma clinic. Diagnosis of PDS was made when they had normal optic disc, normal visual field {with or without increased Intra Ocular Pressure (IOP)} and at least two of the following three signs were found clinically: Krukenberg spindle, homogenous moderate-to-heavy (>= Spaeth 2+) Trabecular Meshwork (TM) pigmentation, and any degree of zonular and/or lenticular pigment granule dusting. Patients with PDS were diagnosed with PG, if they had two or more of the following findings: initial IOP >21 mmHg, glaucomatous optic nerve damage or glaucomatous visual field loss. Various parameters such as influence of demographics, IOP, Best-Corrected Visual Acuity (BCVA), Central Corneal Thickness (CCT), Mean Deviation (MD), Visual Field Index (VFI %), spherical equivalent and clinical finding of anterior segment of study patients were analysed. Mean, standard deviation and percentage were calculated using GraphPad Instat version 3.0. Results: Among 40 patients, nine eyes of the six patients had myopia of 0.5D or greater, with mean refractive error of 3.55 +/- 4.72 spherical equivalent. The average baseline IOP in study patients (PDS+PG), was 30.21 +/- 11.42 mmHg. Twenty four (60%) patients, either in one or both eyes had glaucoma, secondary to PDS at the initial diagnosis. Thirty three (82.5%) patients had Krukenberg spindles. Homogeneous TM pigmentation was seen in all patients. Typical spoke-like radial Iris Transillumination Defects (ITDs) were not observed in any of the patients except in one patient, who had isolated short slit-like trans-illumination defects in iris crypts. Conclusion: It can be concluded that PDS patients with normal optic disc and visual field and raised IOP, should be started prophylactic treatment and needs to be monitored more closely. Thus, the finding of PDS in Indians should alert the ophthalmologist to look for glaucoma during the initial examination.