Pseudoexfoliation (PEX) is an age-related idiopathic condition characterized by progressive production and accumulation of extracellular matrix fibrillary material in the intraocular and extraocular tissues.[1] The prevalence of PEX over the age of 60 years is roughly 10-20%, increasing to 40%over the age of 80 years, and is highly dependent on race and ethnicity.[2,3] It was first described by Lindberg in 1917, as an age-related systemic disorder with primary ocular manifestation having strong genetic component that has a genetic linkage to lysyl –oxidase-like-one (LOXL-1) gene. [4]

Ocular involvement in PEX primarily manifests with anterior segment findings. PEX material accumulation has also been found on the lens capsule, pupillary border, the iris, non-pigmented ciliary epithelium, lens zonules, trabecular meshwork, corneal endothelial cells in the posterior ciliary artery, vortex vein and central retinal artery walls. The material has also been demonstrated along vascular endothelium, corneal epithelial basement membrane and stroma. Moreover, various clinical studies have reported that PEX material affects ocular blood flow and vascular resistance. In fact, PEX is also considered as a systemic vascular disease, referred to as PEX vasculopathy.[5]

Outside of IOP measurements no clinical bio markers are currently used to quantify the severity of PEX. There is a dearth of such studies in the hilly area of Himachal Pradesh. The objective of the study, therefore, was to describe the ocular as well as intra-ocular findings among the patients with pseudoexfoliation without glaucoma (PEX) among the study participants attending an ophthalmic Out Patient Department clinic in a tertiary care hospital of North India. 

The present cross-sectional descriptive study was conducted in the Department of Ophthalmology, Indira Gandhi Medical College, Shimla among the selected patients of pseudo exfoliation with glaucoma from July 2018 through June 2019 i.e. one year. Assuming a difference of average RNFL thickness of 11.69(mm) [6], Confidence level 95%, Absolute error as 5%, and power of study 80%, a sample size of 46 was calculated. All consecutive patients presenting to ophthalmology OPD and diagnosed with pseudo exfoliation with glaucoma and were willing to participate were included in the study till the completion of sample size. The rest who did not fulfil our inclusion criteria were excluded from our study. The data was entered and cleaned using Microsoft Excel Spreadsheet 2007. The data was analyzed using SPSS v22. The quantitative variables were expressed as mean and standard deviation whereas the qualitative variables were expressed as frequencies and proportions. Prior permission was taken from ethical committee of Indira Gandhi Medical College, Shimla to go ahead with the study.

There were 46 study participants of which there were 24 males and 22 females. The mean age of patients with Pseudoexfoliation was 68.43±9.88 years. The visual activity was in the range from 6/6 to FC 2/60 in the left eye as well as in the right eye. An intra ocular pressure (IOP) of less than 10 mm Hg was found in one-fourth of the participants while the rest had an IOP ranging from 10-20 mm, and none had an IOP of more than  21 mm Hg in the left eye, whereas an IOP of <10 mm Hg was found to be in nearly 28% of the patients, while two-third of the patients had an IOP ranging between 10-20 mg Hg whereas the rest had an IOP of >21 mm Hg in the right eye. Vertical cup disc between 0.3 -0.4 was found in 39 patients while a cup disc between 0.5 and 0.6 was found to be among the rest of the study participants. (Table 1)

The mean RNFL Thickness(µm) in Left Nasal, Left Temporal, Left Superior, Left Inferior, Right Nasal, Right Temporal, Right Superior, Right Inferior quadrant was 74.70±20.506,67.61±20.477,        118.59±23.053,113.07±23.449,70.35±20.068, 96.46±31.758, 106.78±26.168,106.78±26.168 respectively and the overall mean RNFL Thickness was found to be 89.47±13.52 µm. (Table 2)

Non-Contact Specular Microscope (Topcon SP-1P Version 1.41) was used to evaluate the following morphometric parameters in the corneal endothelial cells and it was found that the Mean Central Corneal Thickness (CCT) in our study participants was 496.74±30.873 µm, Mean Endothelialcell density(ECD) was 2586.33±505.156 cells/mm², Mean Coefficient of variation (CV) 37.37 ± 4.25%, whereas the Mean Hexagonal Ratio (HR) was found to be 29.74 ± 9.15 %. (Table 3)

PXF syndrome is a complex systemic disorder of the extracellular matrix primarily affecting the eye and visceral organs characterized by the deposition of fibrillar material on all anterior segment structures.

Prevalence of PXF increases markedly with age.The mean age in patients of Pseudoexfoliation without Glaucomawas 68.43±9.88 years. In contrary to our study,  it was observed that PEX prevalence increases markedly with age as shown by other studies done [7-10].In our study PEX shows a male preponderance as shown by other studies done [7-10]

Among visual acuity in left eye of study participants 47.82% patients were having visual acuity between 6/6 to 6/12, 21.73% patients with visual acuity between 6/18 to 6/36 and 30.43% patients presented with visual acuity from 6/60 or worse. Among visual acuity in right eye of study participants 30.43% patients were having visual acuity between 6/6 to 6/12, similar percentage of patients were having visual acuity between 6/18 to 6/36 whereas 39.13% of patients were having visual acuity between 6/60 or worse. Similar results were observed in study done [11]  In contrary to our study findings, there were higher measurements in the study done [12]  intra ocular pressure between 10-21 mm of Hg was found in the majority of our study participants. Similar results were observed in study done [13]  In contrary to our study findings, there were higher measurements in the study done [14]

Mean RNFL thickness was seen decreased in all PEX patients in all quadrants. Mean total RNFL thickness(µm) was 89.47±13.5. Similar findings  were reported in study done [15] in which  RNFL thickness was higher in the paeitents affected with PEX.Thinner RNFL measurements may be related with the increasing risk of development of glaucoma in PEX patients. In our study mean CCTs were thinner (496.74±30.873 µm). Similar to our study, Inoue and coworkers[16] reported thinner corneas in individuals with PEX. Contrary to our study ,Kitsos and colleague[17] showed that CCT was not affected by the presence of PEX and their results were in agreement with previous studies.Lower CCT values in the eyes with PEX material may be a result of decrease in corneal stromal cell density. In our study Mean endothelial cell densities were 2586.3 ± 505.15) cells/ mm^{2 .}Mean Coefficient of variation (CV) was 37.37±4.26%. Mean Hexagonal Ratio was 29.74±9.15 %. Similar findings were reported in study done [13]

Our study indicated that there were more morphological abnormalities of corneal endothelial cells and decrease in RNFL thickness in patients with PEX. The RNFL thickness and Endothelial Cell Density seem to be reduced, thus leading to progressive corneal damage. Further analytical studies are required to prove our findings.

Conflict of Interest: The authors declare that they have no conflict of interest

Funding: No funding sources

Ethical approval: The study was approved by the IGMC Shimla, Himachal Pradesh

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