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The heart is a muscular organ about the size of a closed fist that function by pumping blood throughout the body making the body size extremely important in its performance. Hence, the work done by the heart depend largely on the total body size of the individual, measurements of which depends on the weight and height to estimate BMI, BSA and BSI. The aim of the study was to establish Ghanaian based standard reference values of cardiothoracic ratio and determine the relationship with body parameters for clinical application. The maximum transverse diameter of the heart was obtained by adding the widest distance of the right heart border from the midline and the left heart border to the midline (cardiac diameter). This value was then divided by the maximum transverse diameter of the thorax (the thoracic diameter) to give the cardiothoracic ratio (CTR). Which is described as a ratio of the cardiac width as against thoracic width. The measured CTR was approximately 15: 33 (cm) and is therefore within the normal limit of 50%. This is because a CTR of greater than fifty percent is abnormal, in terms of Posterior - Anterior (PA) or an Anterior - Posterior (AP) view. In addition, the height and weight were measured to estimate the BMI, BSA and BSI and the relationship of these parameters with the measured cardiothoracic ratio. The result shows that BSI better correlate with the cardiothoracic ratio than any other body parameter with 92.53% accuracy rate. The determination of the CTR which represent the size of the normal heart is of the greatest importance to cardiologists. This is because the heart size enlargement is better assess by determining the ratio of size of the heart (cardiac diameter) as against the size of the chest wall (the thoracic diameter). This is use for initial assessment of heart condition by cardiologist, with a standard adult heart having a CTR value of 0.5. The study shows that a normal size is so variable and depends so greatly on the sex, age and body parameters of the study population. In conclusion, the study will serve as basis of the relationship between body parameter and the CTR. It also established that a deviation of heart size with BSI may reveal an underlying pathologic condition, and called for further studies to be conducted for clinical decision.

The relationship between body height and body weight has been described by using various terms. Notable among them is the body mass index, body surface area, body shape index and body surface index. In clinical setting the first descriptive parameter is the BMI scale, which provides information about whether an individual body weight is proportionate to the body height. Since the development of BMI, two other body parameters have been developed in an attempt to determine the relationship between body height and weight. These are the body surface area (BSA) and body surface index (BSI). Generally, these body parameters are described as clinical health indicators that described how healthy an individual body response to the other internal organs. The aim of the study is to discuss the use of BSI as a better clinical health indicator for preclinical assessment of body-organ/tissue relationship. Hence organ health condition as against other body composition. In addition the study is `also to determine the best body parameter the best predict other parameters for clinical application. The model parameters are presented as; modeled height and weight; modelled BSI and BSA, BSI and BMI and modeled BSA and BMI. The models are presented as clinical application software for comfortable working process and designed as GUI and CAD for use in clinical application.

The quantities that determine the relative image noise level by either increasing or reducing its value are photon quality (kVp) and photon quantity (mAs). This study is to determine the effect of LET, energy and particle fluence on the renal surface area during abdominal CT scan. The method involve extracting three exposure parameters from image data using MVL DICOM application software including: kVp, mA and scan time. The kVp or the photon peak energy which is applied in the A-P direction during abdominal CT scan was used to estimate linear energy transfer. While the particle fluence and the energy fluence were estimated from the effective mAs and the kVp on the total renal surface respectively. The effective mAs were estimated by dividing the mAs by the average pitch factor of approximately 0.813. In all the examinations, the average protocol setting in terms of exposure time and kilovolts peak were 500s and 120keV respectively. While the average protocol in all the centers recorded a mean effective milliamp second (mAs) of 59.27 mAs and tube current of 94.22A. The influence of these parameters on abdominal scan depends on the scan time, scan scope, the size of the renal surface area (RSA) which has varied values. The effects of effective mean mAs per unit mean renal surface area, described as mean effective particle fluence were 1.32mAs/cm2 and 1.50 mAs/cm2 for male and female respectively. The energy fluence, which is the photon energy per unit renal surface area estimated to have a mean value of 4.02 keVcm-2 and 4.51 keVcm-2 for male and female respectively. In addition, the maximum and minimum variations of all the measured parameters. The LET, which described the lost in photon energy as it traverses across the renal tissues in the A-P direction was estimated, with a mean value of 2.60 keV/µm and 2.67 keV/µm for male and female respectively. The maximum and minimum LET values were 4.49 keV/µm and 1.90 keV/µm for male and 5.26 keV/µm and 1.98 keV/µm for female respectively. The maximum measured values were below the critical LET values estimated to be between 15 to 20 keV/µm. These estimated risk parameters were used to predict the effect on abdominal and kidney tissues using the various modeled equations.