International Journal of Radiation Research, January 2014 Volume 12, No 1 Estimation of radiation dose to the lens of eyes of patients undergoing cranial computed tomography in a teaching Hospital in Osun state, Nigeria INTRODUCTION Radiological examination utilizing X‐rays remains the most frequently used ionizing radiation in Medicine, constituting the most signiϐicant manmade source of radiation exposure to the world population (1,2) . In diagnostic radiology, periodic dose assessments are carried out to encourage the optimization of the radiation protection of patients (3) . Dose measurements are required in every hospital to ensure compliance with acceptable dose limit. During the past two decades, several radiation dose surveys have been undertaken in many countries around the world. One of the outcomes of these efforts was the recognition of signiϐicant variations in patient doses between different radiological departments for the same type of examination (4) . These variations in dose within and among hospitals justify dose assessment in order to optimize the diagnostic radiological practice (5) . During recent years, dose to patient has become a major issue because of the increasing awareness and greater realization of the effects of ionizing radiation. N.N. Jibiri * and A.A. Adewale Radiation and Health Physics Research Laboratory, Department of Physics, University of Ibadan, Ibadan, Nigeria ABSTRACT   Background: One of the means of assessing dose to paƟents from Computed tomography (CT) procedure is through the determinaƟon of the skin entrance dose (ESD) with the appreciaƟon of the concern that ocular exposure effects from CT scan includes possible inducƟon of cancer and cataract. Due to the relaƟvely more recent introducƟon of CT scans, liƩle work has been done in this area in the country including exposure dose on the lens of the eyes of paƟents undergoing Cranial Computed Tomography (C‐CT). Materials and  Methods: The Entrance Surface Dose (ESD) to the lens of eyes of 26 paƟents who had cranial CT procedures at a University Teaching Hospital in Ile‐Ife, Nigeria has been determined in order to assess the level of radiaƟon protecƟon compliance and opƟmizaƟon of radiaƟon safety at the hospital. Results: Results indicate that the doses to the paƟents ranged between 17.13 mGy and 51.98 mGy within the period under study. The average doses obtained for the pediatric paƟents (1.5‐18 yrs), young adults (19‐49 yrs) and adults (≥50 yrs) were 31.14 ±11.02 mGy, 41.81±12.60 mGy and 31.97 ± 11.31 mGy respecƟvely. The mean dose obtained in this study was lower than threshold for lens damage, therefore the dose recorded in this study is clinically safe. Conclusion: This study represents a requisite pedestal on the need for a naƟon‐wide evaluaƟon and invesƟgaƟon of opƟmizaƟon of procedures in radiological examinaƟons with a view to establishing a naƟonal dosimetry protocol and reference dose level or guidance level in the country. Keywords: Patients, cranial computed tomography, entrance surface dose, lens of the eyes, University teaching hospital. * Corresponding author: Dr. Nnamdi N. Jibiri, Fax: +234 02 8103043 E‐mail: nnamdi.jibiri@mail.ui.edu.ng Submitted: Dec. 2012 Accepted: June 2013 Int. J. Radiat. Res., January 2014; 12(1): 53-60 ► Original article Downloaded from ijrr.com at 12:08 +0330 on Monday November 29th 2021