Journal of Clinical and Diagnostic Research, ISSN - 0973 - 709X

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On Sep 2018




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Prof. Somashekhar Nimbalkar
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On Sep 2018




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"Journal of Clinical and Diagnostic Research is at present a well-known Indian originated scientific journal which started with a humble beginning. I have been associated with this journal since many years. I appreciate the Editor, Dr. Hemant Jain, for his constant effort in bringing up this journal to the present status right from the scratch. The journal is multidisciplinary. It encourages in publishing the scientific articles from postgraduates and also the beginners who start their career. At the same time the journal also caters for the high quality articles from specialty and super-specialty researchers. Hence it provides a platform for the scientist and researchers to publish. The other aspect of it is, the readers get the information regarding the most recent developments in science which can be used for teaching, research, treating patients and to some extent take preventive measures against certain diseases. The journal is contributing immensely to the society at national and international level."



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Professor and Head
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Saraswati Dental College
Lucknow
On Sep 2018




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Calcutta National Medical College & Hospital , Kolkata




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C.S. Ramesh Babu,
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Muzaffarnagar.
On Aug 2018




Dr. Arundhathi. S
"Journal of Clinical and Diagnostic Research (JCDR) is a reputed peer reviewed journal and is constantly involved in publishing high quality research articles related to medicine. Its been a great pleasure to be associated with this esteemed journal as a reviewer and as an author for a couple of years. The editorial board consists of many dedicated and reputed experts as its members and they are doing an appreciable work in guiding budding researchers. JCDR is doing a commendable job in scientific research by promoting excellent quality research & review articles and case reports & series. The reviewers provide appropriate suggestions that improve the quality of articles. I strongly recommend my fraternity to encourage JCDR by contributing their valuable research work in this widely accepted, user friendly journal. I hope my collaboration with JCDR will continue for a long time".



Dr. Arundhathi. S
MBBS, MD (Pathology),
Sanjay Gandhi institute of trauma and orthopedics,
Bengaluru.
On Aug 2018




Dr. Mamta Gupta,
"It gives me great pleasure to be associated with JCDR, since last 2-3 years. Since then I have authored, co-authored and reviewed about 25 articles in JCDR. I thank JCDR for giving me an opportunity to improve my own skills as an author and a reviewer.
It 's a multispecialty journal, publishing high quality articles. It gives a platform to the authors to publish their research work which can be available for everyone across the globe to read. The best thing about JCDR is that the full articles of all medical specialties are available as pdf/html for reading free of cost or without institutional subscription, which is not there for other journals. For those who have problem in writing manuscript or do statistical work, JCDR comes for their rescue.
The journal has a monthly publication and the articles are published quite fast. In time compared to other journals. The on-line first publication is also a great advantage and facility to review one's own articles before going to print. The response to any query and permission if required, is quite fast; this is quite commendable. I have a very good experience about seeking quick permission for quoting a photograph (Fig.) from a JCDR article for my chapter authored in an E book. I never thought it would be so easy. No hassles.
Reviewing articles is no less a pain staking process and requires in depth perception, knowledge about the topic for review. It requires time and concentration, yet I enjoy doing it. The JCDR website especially for the reviewers is quite user friendly. My suggestions for improving the journal is, more strict review process, so that only high quality articles are published. I find a a good number of articles in Obst. Gynae, hence, a new journal for this specialty titled JCDR-OG can be started. May be a bimonthly or quarterly publication to begin with. Only selected articles should find a place in it.
An yearly reward for the best article authored can also incentivize the authors. Though the process of finding the best article will be not be very easy. I do not know how reviewing process can be improved. If an article is being reviewed by two reviewers, then opinion of one can be communicated to the other or the final opinion of the editor can be communicated to the reviewer if requested for. This will help one’s reviewing skills.
My best wishes to Dr. Hemant Jain and all the editorial staff of JCDR for their untiring efforts to bring out this journal. I strongly recommend medical fraternity to publish their valuable research work in this esteemed journal, JCDR".



Dr. Mamta Gupta
Consultant
(Ex HOD Obs &Gynae, Hindu Rao Hospital and associated NDMC Medical College, Delhi)
Aug 2018




Dr. Rajendra Kumar Ghritlaharey

"I wish to thank Dr. Hemant Jain, Editor-in-Chief Journal of Clinical and Diagnostic Research (JCDR), for asking me to write up few words.
Writing is the representation of language in a textual medium i e; into the words and sentences on paper. Quality medical manuscript writing in particular, demands not only a high-quality research, but also requires accurate and concise communication of findings and conclusions, with adherence to particular journal guidelines. In medical field whether working in teaching, private, or in corporate institution, everyone wants to excel in his / her own field and get recognised by making manuscripts publication.


Authors are the souls of any journal, and deserve much respect. To publish a journal manuscripts are needed from authors. Authors have a great responsibility for producing facts of their work in terms of number and results truthfully and an individual honesty is expected from authors in this regards. Both ways its true "No authors-No manuscripts-No journals" and "No journals–No manuscripts–No authors". Reviewing a manuscript is also a very responsible and important task of any peer-reviewed journal and to be taken seriously. It needs knowledge on the subject, sincerity, honesty and determination. Although the process of reviewing a manuscript is a time consuming task butit is expected to give one's best remarks within the time frame of the journal.
Salient features of the JCDR: It is a biomedical, multidisciplinary (including all medical and dental specialities), e-journal, with wide scope and extensive author support. At the same time, a free text of manuscript is available in HTML and PDF format. There is fast growing authorship and readership with JCDR as this can be judged by the number of articles published in it i e; in Feb 2007 of its first issue, it contained 5 articles only, and now in its recent volume published in April 2011, it contained 67 manuscripts. This e-journal is fulfilling the commitments and objectives sincerely, (as stated by Editor-in-chief in his preface to first edition) i e; to encourage physicians through the internet, especially from the developing countries who witness a spectrum of disease and acquire a wealth of knowledge to publish their experiences to benefit the medical community in patients care. I also feel that many of us have work of substance, newer ideas, adequate clinical materials but poor in medical writing and hesitation to submit the work and need help. JCDR provides authors help in this regards.
Timely publication of journal: Publication of manuscripts and bringing out the issue in time is one of the positive aspects of JCDR and is possible with strong support team in terms of peer reviewers, proof reading, language check, computer operators, etc. This is one of the great reasons for authors to submit their work with JCDR. Another best part of JCDR is "Online first Publications" facilities available for the authors. This facility not only provides the prompt publications of the manuscripts but at the same time also early availability of the manuscripts for the readers.
Indexation and online availability: Indexation transforms the journal in some sense from its local ownership to the worldwide professional community and to the public.JCDR is indexed with Embase & EMbiology, Google Scholar, Index Copernicus, Chemical Abstracts Service, Journal seek Database, Indian Science Abstracts, to name few of them. Manuscriptspublished in JCDR are available on major search engines ie; google, yahoo, msn.
In the era of fast growing newer technologies, and in computer and internet friendly environment the manuscripts preparation, submission, review, revision, etc and all can be done and checked with a click from all corer of the world, at any time. Of course there is always a scope for improvement in every field and none is perfect. To progress, one needs to identify the areas of one's weakness and to strengthen them.
It is well said that "happy beginning is half done" and it fits perfectly with JCDR. It has grown considerably and I feel it has already grown up from its infancy to adolescence, achieving the status of standard online e-journal form Indian continent since its inception in Feb 2007. This had been made possible due to the efforts and the hard work put in it. The way the JCDR is improving with every new volume, with good quality original manuscripts, makes it a quality journal for readers. I must thank and congratulate Dr Hemant Jain, Editor-in-Chief JCDR and his team for their sincere efforts, dedication, and determination for making JCDR a fast growing journal.
Every one of us: authors, reviewers, editors, and publisher are responsible for enhancing the stature of the journal. I wish for a great success for JCDR."



Thanking you
With sincere regards
Dr. Rajendra Kumar Ghritlaharey, M.S., M. Ch., FAIS
Associate Professor,
Department of Paediatric Surgery, Gandhi Medical College & Associated
Kamla Nehru & Hamidia Hospitals Bhopal, Madhya Pradesh 462 001 (India)
E-mail: drrajendrak1@rediffmail.com
On May 11,2011




Dr. Shankar P.R.

"On looking back through my Gmail archives after being requested by the journal to write a short editorial about my experiences of publishing with the Journal of Clinical and Diagnostic Research (JCDR), I came across an e-mail from Dr. Hemant Jain, Editor, in March 2007, which introduced the new electronic journal. The main features of the journal which were outlined in the e-mail were extensive author support, cash rewards, the peer review process, and other salient features of the journal.
Over a span of over four years, we (I and my colleagues) have published around 25 articles in the journal. In this editorial, I plan to briefly discuss my experiences of publishing with JCDR and the strengths of the journal and to finally address the areas for improvement.
My experiences of publishing with JCDR: Overall, my experiences of publishing withJCDR have been positive. The best point about the journal is that it responds to queries from the author. This may seem to be simple and not too much to ask for, but unfortunately, many journals in the subcontinent and from many developing countries do not respond or they respond with a long delay to the queries from the authors 1. The reasons could be many, including lack of optimal secretarial and other support. Another problem with many journals is the slowness of the review process. Editorial processing and peer review can take anywhere between a year to two years with some journals. Also, some journals do not keep the contributors informed about the progress of the review process. Due to the long review process, the articles can lose their relevance and topicality. A major benefit with JCDR is the timeliness and promptness of its response. In Dr Jain's e-mail which was sent to me in 2007, before the introduction of the Pre-publishing system, he had stated that he had received my submission and that he would get back to me within seven days and he did!
Most of the manuscripts are published within 3 to 4 months of their submission if they are found to be suitable after the review process. JCDR is published bimonthly and the accepted articles were usually published in the next issue. Recently, due to the increased volume of the submissions, the review process has become slower and it ?? Section can take from 4 to 6 months for the articles to be reviewed. The journal has an extensive author support system and it has recently introduced a paid expedited review process. The journal also mentions the average time for processing the manuscript under different submission systems - regular submission and expedited review.
Strengths of the journal: The journal has an online first facility in which the accepted manuscripts may be published on the website before being included in a regular issue of the journal. This cuts down the time between their acceptance and the publication. The journal is indexed in many databases, though not in PubMed. The editorial board should now take steps to index the journal in PubMed. The journal has a system of notifying readers through e-mail when a new issue is released. Also, the articles are available in both the HTML and the PDF formats. I especially like the new and colorful page format of the journal. Also, the access statistics of the articles are available. The prepublication and the manuscript tracking system are also helpful for the authors.
Areas for improvement: In certain cases, I felt that the peer review process of the manuscripts was not up to international standards and that it should be strengthened. Also, the number of manuscripts in an issue is high and it may be difficult for readers to go through all of them. The journal can consider tightening of the peer review process and increasing the quality standards for the acceptance of the manuscripts. I faced occasional problems with the online manuscript submission (Pre-publishing) system, which have to be addressed.
Overall, the publishing process with JCDR has been smooth, quick and relatively hassle free and I can recommend other authors to consider the journal as an outlet for their work."



Dr. P. Ravi Shankar
KIST Medical College, P.O. Box 14142, Kathmandu, Nepal.
E-mail: ravi.dr.shankar@gmail.com
On April 2011
Anuradha

Dear team JCDR, I would like to thank you for the very professional and polite service provided by everyone at JCDR. While i have been in the field of writing and editing for sometime, this has been my first attempt in publishing a scientific paper.Thank you for hand-holding me through the process.


Dr. Anuradha
E-mail: anuradha2nittur@gmail.com
On Jan 2020

Important Notice

Original article / research
Year : 2021 | Month : August | Volume : 15 | Issue : 8 | Page : NC15 - NC18 Full Version

Determination of Corneal Endothelial Cell Count and Morphology in Patients with Pseudoexfoliation: A Cross-control Study


Published: August 1, 2021 | DOI: https://doi.org/10.7860/JCDR/2021/41281.15285
Purva Shailesh Nagle, Varsha Nitin Kulkarni

1. Resident, Department of Ophthalmology, Bharati Vidyapeeth Deemed To Be University, Pune, Maharashtra, India. 2. Professor, Department of Ophthalmology, Bharati Vidyapeeth Deemed To Be University, Pune, Maharashtra, India.

Correspondence Address :
Purva Shailesh Nagle,
Rachna Chaitraban, Aundh, Pune, Maharashtra, India.
E-mail: purvanagle@gmail.com

Abstract

Introduction: Pseudoexfoliation Syndrome (PEX) is characterised by the formation or deposition of abnormal fibrillar material on intraocular structures. Various ocular complications, such as chronic open-angle glaucoma, zonular dehiscence causing lens subluxation/dislocation, poor mydriasis are associated with PEX. In PEX eyes, corneal endothelial changes have been demonstrated along with thinner Central Corneal Thickness (CCT).

Aim: To evaluate the CCT, corneal Endothelial Cell Density (ECD) and morphology in patients with pseudoexfoliation and to compare the results with age matched controls.

Materials and Methods: A case-control study was done on a total of 147 eyes of 81 patients with pseudoexfoliation with equal number of eyes in age matched controls were evaluated for corneal ECD, coefficient of variation in cell size, percentage of hexagonal cells and CCT using a non-contact specular microsope. The quantitative data was represented as their mean±Standard Deviation (SD). The paired t-test was used for analysing quantitative data.

Results: The average ECD in the PEX group was 2301.30±117.37 cells/mm2. It was significantly lower than the average ECD in controls 2632.91±24.04 cells/mm2 (p-value <0.001). The average CCT in the PEX group was 508±19.09 microns and in the age matched controls was 524.22±6.36 microns. The average CCT was low in the PEX group and difference was statistically significant (p≤0.001). The coefficient of variation and percentage of hexagonality were altered but did not show any statistical significance in both the groups.

Conclusion: ECD and CCT is significantly decreased in eyes with PEX. Pleomorphism and polymegathism was not found significant in this study.

Keywords

Central corneal thickness, Endothelium, Hexagonality, Pleomorphism

The Pseudoexfoliation Syndrome (PEX) is the deposition of abnormal fibrillar material upon intraocular structures (1). The pseudoexfoliative material is seen on the corneal endothelium, anterior lens surface, iris, trabecular meshwork, zonules and ciliary body (2),(3). It is often associated with ocular complications like pseudoexfoliative glaucoma, zonular dehiscence causing lens subluxation/dislocation and poor mydriasis. Exfoliative material is a homogenous, eosinophilic, periodic acid-Schiff positive staining substance. Electron microscopy demonstrates a loose fibrillar structure, with individual fibrils being generally 20-30 nm thick and having a characteristic 50 nm macroperiodicity. The source of the exfoliative material is thought to be over production of zonular tissue by the non-pigmented ciliary epithelium and the equatorial lens epithelium because the lens zonules have similar ultrastructural, staining, and immunological properties (4).

The reported prevalence of PEX in general population varies from country to country. The lowest prevalence was found to be 0% in Eskimos and the highest prevalence of 8.2% was reported in Bantu tribes of South Africa. A population based study in South India reported a prevalence of 3.41% (5).

This syndrome is slightly more common in females than males. The corneal endothelium is the posterior most surface of the cornea. It is made up of simple squamous or low cuboidal monolayer of hexagonal cells. The normal ECD is about 3000-5000 cells/mm2 and is responsible for regulating fluid and solute transport between the aqueous and corneal stromal compartments and are rich in mitochondria (2).

These cells are derived from neuroectoderm. They do not have the ability to replicate. The ECD is approximately 5,00,000 at birth. It decreases with age because of constant wear and tear. When the endothelial cells die, neighboring cells expand to cover the empty space once occupied by them. Maintaining a healthy and transparent corneal stroma is the primary physiological function of the corneal endothelium. It also secretes a collagen matrix that forms Descemet’s membrane (6). The intraocular pressure regularly forces aqueous into the stroma from the anterior chamber to facilitate diffusion. Even though the influx of aqueous into the stroma is essential for maintenance of corneal health, however to prevent oedema, the level of corneal hydration must be controlled (7).

Exact aetiology of PEX is not known. Multiple inheritance patterns have been suggested. Three Single Nucleotide Polymorphisms (SNPs) in a lysyl oxidase like one gene have been identified. LOXL1 and elastin are expressed in the corneal endothelium, anterior lens surface, iris, trabecular meshwork, zonules and ciliary body (5),(6). The source of the exfoliative material is thought to be over production of zonular tissue by the nonpigmented ciliary epithelium and the equatorial lens epithelium because the lens zonules have similar ultrastructural, staining, and immunological properties (7).

The deposition of the PEX material in the corneal endothelium leads to decreased nutrition to the stroma. There is also an increased oxidative stress to the corneal stroma which causes a decrease in the number of keratocytes and in the end leads to the damage of its extracellular structure which may result in the thinning of the cornea. The decreased number of keratocytes has been demonstrated in-vivo confocal microscopy by Zheng X et al., and Oltulu R et al., in their studies (8),(9). The progressive loss of endothelium due to chronic disorders may also affect the transparency as well as the functioning of cornea. If the ECD is less than 500/mm2, corneal decompensation sets in causing corneal oedema and bullous keratopathy (10).

Studies conducted earlier have revealed PEX patients to have thinner corneas and increased susceptibility to develop glaucoma (11),(12),(13),(14). Data has reported from India on evaluation of the endothelium in patients diagnosed to have pseudoexfoliation (15). The aim of this study was to understand the changes in the CCT, endothelial morphology and ECD in patients with PEX and to correlate the results with age matched controls.

Material and Methods

A case-control study was conducted at Department of Opthalmology in Bharati Vidyapeeth Deemed to be University, Pune, Maharashtra, India, during May 2017 to September 2018 in which total of 147 eyes of 81 patients with pseudoexfoliation and equal number of age matched healthy controls were evaluated after the approval of the ethical committee (REF: BVDUMC/IEC/64. Dated: 10/10/2017). Sample size was calculated in comparison of previous study (15).

Diagnosis of the syndrome was based on the slit-lamp appearance of pseudoexfoliative material at the anterior lens capsule and/or at the pupillary margin, iris and endothelium. A written informed consent was obtained.

All patients were subjected to a complete ophthalmic evaluation which included recording of Best Corrected Visual Acuity (BCVA), anterior segment evaluation using slit lamp bio microscope and intraocular pressure using Goldmann Applanation Tonometer. Posterior segment was evaluated with Volk 90 D lens.

The corneal endothelium was evaluated using a TOPCON SP-18P specular microscope by a single observer. The endothelial morphology was quantitated by measuring parameters including cell density, coefficient of variation in the cell area, and the percentage of hexagonal cells. The CCT was also evaluated by specular microscopy.

Controls selected were age matched and had no pseudoexfoliative material at the anterior lens capsule or pupillary margin, no previous intraocular surgery, and no abnormalities of the cornea and underwent the same method of investigation.

Inclusion Criteria

• Patients having pseudoexfoliation of any age and gender.
• Patients willing to give written informed consent and follow study related procedures.

Exclusion Criteria for Controls and Case

• Patients with viral infections like Herpes zoster, Herpes simplex, Cytomegalovirus.
• Any kind of ocular trauma.
• Conditions affecting cornea like Fuch’s dystrophy, Keratoconus, Aphakic bullous keratopathy, Pseudophakic bullous keratopathy.
• Operative procedure like Cataract surgery, Laser iridotomy, Penetrating keratoplatsy.
• Refractive corneal surgeries.
• Diagnosed cases of glaucoma.
• Diagnosed cases of diabetes mellitus.

Statistical Analysis

The quantitative data was represented as their mean±SD. The paired t-test was used for analysing quantitative data. The significance threshold of p-value of <0.05 was considered significant. All analysis was carried out by using Statistical Package for the Social Sciences (SPSS) software version 21.

Results

A total of 147 eyes of 81 patients with PEX were included in this study. There were 45 females and 36 were males in both the groups. The maximum number of patients diagnosed to have PEX were in the age group 56-65 years (n=56 eyes) and 66-75 years (n=71 eyes). The average CCT in the PEX group was 508±19.09 microns and in the age matched controls was 524.22±6.36 microns. The average CCT was low in the PEX group and difference was statistically significant (p≤0.001). The age groups with a statistically significant difference in the CCT were between the groups 56-65 years (n=56 eyes) and 66-75 years (n=71 eyes) (Table/Fig 1).

The mean ECD in the PEX group was 2301.30±117.37 cells/mm2 and in the age matched controls was 2632.91±24.04 cells/mm2. The average ECD was lower in the PEX group than the control group and the difference was statistically significant (p≤0.001) (Table/Fig 2). Coefficient of variation was not statistically significant in any age group (Table/Fig 3). The hexagonality of cells showed progressive decrease in all age groups in the PEX group and in control. The difference in both the groups was not statistically significant in any age group (Table/Fig 4).

Discussion

The corneal endothelium is a single layer of hexagonal cells of uniform size. The number of cells decrease by 0.5-0.6% (100–200 cells, approximately) per year due to wear and tear. These cells are unable to regenerate. The cell loss is compensated by other endothelial cells migrating and increasing in size to fill the gaps. This in turn causes reduction of the tight junctions between the endothelial cells which leads to corneal oedema due to leak in the corneal endothelium (5),(12).

PEX is an age-related disease which can be clinically diagnosed by the formation or deposition of abnormal fibrillar material upon intraocular structures. Cornea is involved in about 70% of patients with PEX. The observed disorders include increased fragility and progressive loss of the corneal endothelium which lead to pleomorphism and polymegathism (2),(3).

A total of 147 eyes of 81 patients diagnosed to have PEX. Of the 81 patients included in the study, bilateral PEX was present in 79 patients (97.53%). Unilateral PEX was present only in two patients. The maximum number of patients included in our study were between the age groups 56-65 years (38.09%) and 66-75 years (48.29%).

Central Corneal Thickness (CCT)

In our study, the average CCT in the PEX group was 508.65±19.09 microns and that of the control group was 524.22±6.36 microns. This difference was statistically significant (p<0.001). Average CCT in controls in our study was slightly lower as compared to other studies (10),(15).

A study done by Vijaya L et al., in South Indian population the average CCT for the population was 511.4±33.5 microns, which was significantly thinner than the average CCT found in other countries (10). The average CCT in a Turkish study in the non PEX patients was 543±23 and in Japanese population was 549±28 microns (13),(14).

In this study pateints were grouped into increasing age groups, where we detected progressive thinning as the age increased in PEX group as well as in control group. In patients with PEX, the average CCT in age group <55 years was 529.166±12.61 microns. In the age groups of between age groups 55-65 years and 66-75 years had CCT of 515.49±16.06 and 506±20.44 microns, respectively. There was further thinning seen in the age group above 75 years where CCT was 485±30 microns.

In this study, a statistically significant difference in the CCT in the age groups of 56-65 years (p≤0.001) and 66-76 years (p<0.001) in comparison with their age matched controls was found. In a recent Indian study done by Priyadarshini et al., the values were comparable with this study. The mean CCT in their study was 515±0.07 microns in the control group and 501+0.07 microns in PEX group (p-value=0.001) (15).

Inoue K et al., also found the central corneas to be significantly thinner in the PXS eyes 529±31 microns than in the non-PXS eyes 547±28 (p=0.03) (14). Fujisawa A et al., also reported significantly thinner corneas in PEX (524.33±32.79) as compared to the control group (543.23±30.33) (16).

In the age group of <55 years (p=0.805), although the cornea was thinner, there was no statistical significance in comparison to the controls. This may be due to less duration of corneal exposure to the PEX material and less number of patients in this age group. In a study done by Wang M et al., there was no significant change in CCT in the PEX and control group (17).

Deposition of PEX material in the corneal endothelium leads to decreased nutrition to the stroma. There is also an increased oxidative stress to the corneal stroma which causes a decrease in the number of keratocytes and ultimately leads to the damage of its extracellular structure which results in the thinning of the cornea. The decreased number of keratocytes has been demonstrated by invivo confocal microscopy by Zheng X et al., and Oltulu R et al., in their respective studies (8),(9).

PEX is the most common cause of secondary open angle glaucoma. The evaluation of intra ocular pressure is an important parameter for diagnosing glaucoma. The thinner corneas in PEX give a false low reading in the early stages which may lead to a delay in diagnosing pseudoexoliatory glaucoma. Therefore, evaluation of CCT should be done in every patient of PEX syndrome.

Endothelial Cell Density (ECD)

In this study, the average ECD in patients with PEX was 2301.30±117.37 cells/mm² which was significantly lower (p≤0.01) than in the control group 2632.91±24.04 cells/mm² with reduction of 12.57%. The mean ECD (cells/mm2) in the age group 56-65 years was 2310.163±230.157 and in that of 66-75 was 2303.633±276.128. In both these age groups the ECD was significantly lower(p≤0.001) than their age matched controls (Table/Fig 5). A comparision of previous studies was done with the present study (14),(15),(18).

Although the ECD was less than age matched controls in the age group of <55 years, it was not statistically significant (p=0.2295) probably due to lesser duration of the disease process.

PEX influences the cell density of corneal endothelium. PEX material, settles on the endothelium that penetrates into the Descemet’s membrane that eventually breaks the connections between individual six-sided cells, resulting in accelerated apoptosis of these cells. Other factors which may affect the ECD include hypoxia of the anterior chamber, changes in the fibroblasts and elevated concentration of TGF factor (9).

PEX usually affect elderly patients, who are likely to undergo intraocular surgery for cataract and glaucoma. These patients are at a higher risk of endothelial cell loss during surgery because of associated conditions like non-dilating pupil, zonular laxity. Hence, it is advisable to do a specular microscopic evaluation of all patients prior to any intraocular surgery.

Pleomorphism and Polymegathism

In this present study the average coefficient of variation in cell size was 35.04±3.53% in the PEX group and 35.35±8.48% in the controls. This difference was not statistically significant (p <0.6839). coefficient of variation up to 30% is considered normal (9).

The average percentage of hexagonal cells in PEX group was 53.60±1.41% and in the controls was 57.56±16.97 %. The difference between the PEX group and controls was not statistically significant in any age group (p <0.1664). However, there was an overall decrease of the percentage of hexagonal cells in both groups with increasing age. A study done by Inuoue K et al., and Sultana N et al., found similar results to the present study in both pleomorphism and polymegathism (14),(19).

A study conducted by Sarowa S et al., found a significant decrease in the co-efficient of variation in PEX group 39.05±3% and in controls 32.23±2.66% (p <0.05) (20). A similar study done by Wali UK et al., in Omani patients found a significant difference in the co-efficient of variation 37.09±12.43 which was very low in comparison to the controls 33.12±11.44. (p <0.005) (21). This disparity in the findings from our study may be explained by the fact that both these studies had included patients with PEX.

Accelerated apoptosis of the endothelial cells leads to healing by the expansion of the surrounding cells leading to polymegathism. The decrease in the coefficient of variation in the cell area and the percentage of hexagonal cells could be explained by the fact that mild intraocular disturbances or endothelial damages developed slowly over a long period can later result in a decrease in the corneal endothelial cells and their enlargement without transformation of their hexagonal shape (22).

Limitation(s)

This was a time bound study with a smaller sample size. The refractive errors of the patients were not taken into consideration.

Conclusion

A significant decrease in the ECD and CCT in PEX group in comparison to the controls. There was no significant difference in the coefficient of variation of the cell area and percentage of hexagonal cells between the PEX group and the controls in our study.

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DOI and Others

10.7860/JCDR/2021/41281.15285

Date of Submission: Feb 20, 2021
Date of Peer Review: Mar 06, 2021
Date of Acceptance: Apr 13, 2021
Date of Publishing: Aug 01, 2021

AUTHOR DECLARATION:
• Financial or Other Competing Interests: None
• Was Ethics Committee Approval obtained for this study? Yes
• Was informed consent obtained from the subjects involved in the study? Yes
• For any images presented appropriate consent has been obtained from the subjects. NA

PLAGIARISM CHECKING METHODS:
• Plagiarism X-checker: Feb 20, 2021
• Manual Googling: Apr 07, 2021
• iThenticate Software: May 24, 2021 (19%)

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