Normal Ocular Globe Measurements Among Adults, Using Magnetic Resonance Imaging in Zaria, Nigeria: General Ophthalmology

JO Aiyekomogbon; AL Rafindadi

Authors

JO Aiyekomogbon Department of Radiology, College of Health Sciences, University of Abuja, Abuja, Nigeria.
AL Rafindadi Department of Ophthalmology, Ahmadu Bello University Teaching Hospital, Zaria, Nigeria

Abstract

Introduction: The ocular globe measurements are objectively assessed at the level of the lens (mid-globe section)[1,2]. The perpendicular distance of the anterior and posterior margins of the globe to the interzygomatic line (IZL) on axial magnetic resonance imaging (MRI) could accurately determine the position of the globe within the orbit[2] (Figure 1). Also, axial length (AL) of the globe is the distance from the corneal apex to an interference peak corresponding to the retinal pigment epithelium/Bruch’s membrane[3, 4]. It is an indicator of the refractive state of the eye[5]. MRI measurement of AL is also invaluable in the early detection of intrinsic ocular tumours and metastasis to the globe[6]. The aim of this study was to determine the normal AL of the ocular globes with the aid of MRI, and establish the correlation between AL, and age and sex, as well as to determine the normal position of the ocular globe among adults.

Methods: The study was conducted over a six month period from 29th November 2011 to 28th May 2012 at Ahmadu Bello University Teaching Hospital following authorization by the Ethical Committee of the institution. The AL of the globes, and the distance between the anterior and posterior borders of the globe, and IZL were measured at the level of the lens for 340 normal ocular globes of 170 patients on T1-weighted MR images.

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Author Biography

JO Aiyekomogbon, Department of Radiology, College of Health Sciences, University of Abuja, Abuja, Nigeria.

Department of Radiology, Ahmadu Bello University Teaching Hospital, Zaria, Nigeria

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