GENERAL INTRODUCTION

1.1 Background of the study

X-ray is a form of electromagnetic radiation which was discovered on November 8,

1895 by Wilhelm Conrad Roentgen. This ground breaking discovery gave birth to

radiography on December 27, 1895; when Roentgen took the first x-ray image of his

wife‟s hand (Explorable.com, 2010). This made scientists at that time use this amazing

ray to create images of the inside of the human body. But it was not for long when

people started complaining of skin burns and cancer. In the late 1896, Elihu Thomson,

an American physicist, deliberately exposed the little finger of his left hand to an x-ray

tube for several days, half an hour per day which resulted in pain, swelling, stiffness,

erythema and blistering.

In 1942, the leaders of the Manhattan District of U.S. asked Ernest O. Wollan, a cosmic

ray physicist at the University of Chicago, to form a group to study and control

radiation hazards and this was when the word „health physics‟ was born. However,

because of the various complaints that arose as a result of the uses of x-rays, various

bodies (both governmental and non-governmental) were created to provide solutions

and recommendations on how to reduce the adverse effects of radiation (Kathren &

Ziemer, 1980; Turner, 2007). .

1.2 Introduction

Radiation has several applications; it is used in the industry, agriculture, medicine and

research. The medical use of radiation involves its use in conventional radiography,

fluoroscopy, angiography, nuclear medicine (scintigraphy), computed tomography,

mammography and radiotherapy.

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The use of ionizing radiation in clinical practice is on the increase both locally (in

Nigeria) and globally. Certain checks have to be periodically done in order to ensure the

optimization and protection of patients from these dangerous rays; in addition to

investigate compliance level. „Survey data showed that physicians underestimate the

magnitude of radiation doses and their associated detrimental effects and thus

underestimating the level of risk to patients (Mercuri et al., 2011).

Measurements through quality control tests provide a means for setting and checking

standards to ensure good practice as an aid to the optimization of patients‟ protection.

Also estimates of the absorbed and effective doses to skin and tissues/organs in the

patient are needed to determine the associated risks. Data generated provide for

improvement in operations hence justifying techniques and procedures put in place in

diagnostic investigations.

Currently, the two fundamental principles (justification of practice and the optimization

of protection) have been placed under serious scrutiny in the achievement of ALARA in

the diagnostic radiology. In the light of the aforementioned, medical exposures are

receiving increasing attention with the realisation that clinical x-rays make the major

contribution from manmade sources to the population collective dose; also, there is

considerable potential for reducing doses without detriment to patient care (IRPA9,

1996).

Hysterosalpingography (HSG) is a special radiographic examination of the uterine

cavity and the fallopian tubes using radio-opaque dye for the evaluation of infertility in

women. „It involves unavoidable irradiation to the ovaries of women in child bearing

age; therefore, optimization is required in all involving procedures to ensure reduction

in the probability of the associated risk‟ (Suleiman et al., 2008). With the growing

concern about radiation doses received by patients and cancer incidence over the years,

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there has been an emergent requirement for information on typical doses and the range

of doses r