Central Corneal Thickness (CCT) in Open Angle Glaucoma and Glaucoma Suspects in Calabar, Nigeria: Glaucoma

Dennis G. Nkanga; Affiong Andem Ibanga; Elizabeth D. Nkanga; Bassey A. Etim; Kennedy Nwachukwu; Pius O. Ogba

Authors

Dennis G. Nkanga Department of Ophthalmology, University of Calabar, PMB 1115, Calabar, Cross River State, Nigeria.
Affiong Andem Ibanga Department of Ophthalmology, University of Calabar, PMB 1115, Calabar, Cross River State, Nigeria.
Elizabeth D. Nkanga Department of Ophthalmology, University of Calabar Teaching Hospital, Calabar
Bassey A. Etim Department of Ophthalmology, University of Calabar, PMB 1115, Calabar, Cross River State, Nigeria.
Kennedy Nwachukwu Department of Ophthalmology, University of Calabar Teaching Hospital, Calabar
Pius O. Ogba Zerah Eye Hospital and Laser Centre, Plot 103 Ibom Layout, Calabar

Abstract

Introduction: Central Corneal Thickness (CCT) is a measurement of the thickness of the central 3mm of the cornea.[1] It has gained increased significance in glaucoma evaluation and management. This resulted from the observed relationship between CCT and intraocular pressure (IOP) levels.[2-4] CCT varies with age and also among ethnic groups. The Ocular Hypertension study found significantly thinner corneas among African Americans [5-7]. The purpose of this study was therefore to determine to what extent CCT affected IOP and thus management decisions in glaucoma patients and suspects [8,9] .

Methods: A cross sectional study design was chosen. Ethical approval was obtained from the research ethics committee of the University of Calabar Teaching Hospital (UCTH). All consecutive patients seen in the eye clinic of UCTH who were diagnosed with Chronic open angle glaucoma or as Glaucoma suspects from January 2013 to December 2013, were included after an informed consent was obtained for the study. For the purpose of this study a glaucoma suspect is defined as an adult who has one of the following findings in at least 1 eye:

an optic nerve or nerve fiber layer defectsuggestive of glaucoma (enlarged cup–disc ratio, asymmetric cup–disc ratio, notching or narrowing of the neuro-retinal rim, a disc hemorrhage, or suspicious alteration in thenerve fiber layer)

a visual field abnormality consistent withglaucoma

an elevated IOP greater than 21 mm Hg

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Author Biographies

Dennis G. Nkanga, Department of Ophthalmology, University of Calabar, PMB 1115, Calabar, Cross River State, Nigeria.

Department of Ophthalmology, University of Calabar Teaching Hospital, Calabar

Affiong Andem Ibanga, Department of Ophthalmology, University of Calabar, PMB 1115, Calabar, Cross River State, Nigeria.

Department of Ophthalmology, University of Calabar Teaching Hospital, Calabar

Bassey A. Etim, Department of Ophthalmology, University of Calabar, PMB 1115, Calabar, Cross River State, Nigeria.

Department of Ophthalmology, University of Calabar Teaching Hospital, Calabar

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