British Journal of Medicine & Medical Research 15(6): 1-8, 2016, Article no.BJMMR.25239 ISSN: 2231-0614, NLM ID: 101570965
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Corneal Endothelial Cell Density and Morphology in Nigerians Efeoghene U. Ani1*, Sebastain N. N. Nwosu2, Chinyere N. Pedro-Egbe1, Sotonibi A. H. Cookey1 and Elizabeth A. Awoyesuku1 1
Department of Ophthalmology, University of Port Harcourt Teaching Hospital, Rivers State, Nigeria. 2 Department of Ophthalmology, Guinness Eye Centre, Onitsha, Anambra State, Nigeria. Authors’ contributions
This work was carried out in collaboration between all authors. Author SNNN designed the study, wrote the protocol. Author EUA wrote the first draft of the manuscript. Author CNPE managed the literature searches. Author SAHC analysed the data. Authors EUA and EAA carried out the study and collated the data. All authors read and approved the final manuscript. Article Information DOI: 10.9734/BJMMR/2016/25239 Editor(s): (1) Barbara Giambene, Eye Clinic, Department of Translational Surgery and Medicine, University of Firenze, Italy. Reviewers: (1) Vito Romano, Royal Liverpool University Hospital, United Kingdom. (2) Sagili Chandrasekhara Reddy, National Defence University of Malaysia, Malaysia. (3) Lei Ye, National Heart Research Institute, Singapore. (4) Gabor Nemeth, University Teaching Hospital, Miskolc, Hungary. (5) Rahmi Duman, Afyon Kocatepe University, Turkey. (6) Mohammad Mostafa Khater, Tanta University Hospital, Egypt. Complete Peer review History: http://sciencedomain.org/review-history/14397
Original Research Article
Received 23rd February 2016 th Accepted 13 April 2016 Published 1st May 2016
ABSTRACT AIM: To determine the mean density and describe the morphology of corneal endothelial cells in adult Nigerians in Port Harcourt. Study Design: A population-based cross-sectional study. Place and Duration: A study conducted among adult Nigerians aged ≥ 18 years in Port Harcourt city Local Government Area, Rivers State, Nigeria between January and April 2014. Methodology: Participants were selected using multi-stage cluster random sampling technique. An interviewer-based semi-structured questionnaire was administered to obtain demographic data. All participants had ocular examinations done including visual acuity measurement, anterior segment examination, fundoscopy, and non-contact specular microscopy. _____________________________________________________________________________________________________ *Corresponding author: E-mail: [email protected]
Ani et al.; BJMMR, 15(6): 1-8, 2016; Article no.BJMMR.25239
Results: Four hundred and eighty (n=480) subjects were studied. There were 212 males (44.2%) and 268 females (55.8%) with a mean age of 43.0±14.2 years and range 18-91 years. The mean Endothelial Cell Density (ECD) was 2791±221 cells/mm2. Males had a tendency to have a higher 2 2 ECD (2882±220 cells/mm ) than females (2784±215 cells/mm , p=0.490) in ages less than 40 years. 2 Conclusions: The mean ECD obtained in adult Nigerians was 2791±221 cells/mm . No statistically significant difference was found in ECD between males and females. The degree of polymegathism of corneal endothelial cells increased with age in the study population but this was also not statistically significant (p=0.141).
Keywords: Corneal; endothelial; cell; density; adults; Nigeria.
2. MATERIALS AND METHODS
Endothelial cell analysis provides important information on corneal function and viability. Endothelial cell density is an acceptable measure of endothelial cell function . Decisions concerning endothelial health and function in an individual should be based on normative data derived from the reference population. Therefore, it is important for populations of different racial and ethnic backgrounds to establish their own normative data on which decisions regarding endothelial function can be based. A populationbased study is therefore necessary to determine this.
This is a community- based descriptive cross sectional study conducted among adult residents of Port Harcourt City Local Government Area (PHALGA) of River State.
2.1 Inclusion Criteria 1. Adults ≥ 18 years and agreed to participate in this study. 2. No history of ocular surgery, trauma or wearing contact lens 3. No history of corneal disease 4. Visual acuity (VA) ≥ 6/18 5. No systemic comorbidity e.g. diabetes mellitus or hypertension
Endothelial cells that show a great variability in size and shape are considered to be under physiologic stress and abnormal . The corneal endothelial cell wound repair is also reflected as an increase in the variation of individual cell areas, i.e. polymegathism or coefficient of variation (CV). A normal cornea is expected to have 60% of the endothelial cell as hexagons. Stress results in a decrease in the percentage of hexagonal cells. Endothelial cell morphology analysis includes: cell area, cell density, polymegathism (coefficient of variation), and pleomorphism.
2.2 Exclusion Criteria 1. Age ≤ 18 years 2. History of intraocular surgery or trauma 3. Participants receiving medical treatment for glaucoma, hypertension and/or diabetes mellitus 4. Those who had a random blood sugar ≥ 11.1 mmol/L 5. Had vertical cup disc ratio > 0.5 or cup asymmetry of >0.2  6. Those with corneal disease 7. Those who had corneal refractive surgery 8. VA70 Total
The interviewer-administered questionnaire was administered to obtain background information of each eligible participant. Ocular examination and specular microscopy was carried out using a non-contact specular microscope incorporating pachymeter (TYOPTICS, Tianjin Suowei Electronics Technologies LTD, Model SW-7000, China)
2.5 Endothelial Technique Microscopy
Male N (%)
Female N (%)
Total N (%)
43 (20.3) 48 (22.6) 54 (25.5) 38 (17.9) 14 (6.6) 15 (7.1) 212 (44.2)
45 (16.8) 93 (34.7) 70 (26.1) 37 (13.8) 19 (7.1) 4 (1.5) 268 (55.8)
88 (18.3) 141 (29.4) 124 (25.8) 75 (15.6) 33 (6.9) 19 (4.0) 480 (100.0)
Pearson chi-square X2= 17.31, df=5, p = 0.004
3.2 Mean Corneal ECD
Cell Density (ECD) Using Specular
The mean corneal endothelial cell density (ECD) of the study population was 2783.0±215.4 2 cells/mm and this varied with age and gender.
The subject was asked to sit with his chin on the chin rest and forehead against the head rest. He was asked to focus on a green target presented by the instrument. The Specular microscope auto-aligns and measures the central corneal thickness and captures the image of the
The overall mean ECD was 2784.0±218.0 2 2 cells/mm in males and 2782.0±213.9 cells/mm in females. Corneal ECD was higher in male than that of female in groups with age ≤ 40 years (p=0.592). ECD counts were similar between 3
Ani et al.; BJMMR, 15(6): 1-8, 2016; Article no.BJMMR.25239
ages 41 and 50 in both male and female participants (male=2778 cells/mm2 vs. female 2 =2772 cells/mm ). Thereafter, there is a reversal of pattern that females had higher ECD than that of males. However no statistical significance was found (p=0.101).
Table 2. No statistically significant difference was found in the ECD between males and females.
3.4 Relationship between ECD and Age According to Gender Corneal endothelial cell density was found to significantly decrease with age in males and females (p