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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 aim of this study is to estimate the effective dose and assess the lifetime attributable risk of cancer incidence of patients undergoing computed tomography scan at the Korle-Bu Teaching Hospital in the Greater Accra Region of Ghana. Data on Volume CT Dose Index ( ) and Dose Length Product ( ) displayed on the scanner control console was recorded after confirmation of the results by performing independent checks on a phantom. The effective doses were estimated using the displayed and the anatomic region specific conversion factors ( ). The average effective dose for the head, abdomen, chest, neck, and pelvis were 3.63± 2.39mSv, 15.37±8.49 mSv, 12.72 ± 13.97 mSv, 4.04 ± 1.47 mSv and 15.8 ± 3.59 mSv respectively. Effective doses for the head and neck were within the typical range of (1-10mSv) for CT examinations whilst abdomen, chest and pelvis were above 10mSv. The average life attributable risk of cancer incidence for each region of examination were determined from the effective dose, sex and age using the model proposed in BEIR VII Report . The average cancer risk incidence for head, neck, chest, abdomen and pelvis examinations were low in the range 1 in 10,000 to 1 in 1,000. There were wide variations in the effective dose values obtained for the same region under examination. This trend calls for the optimization of CT examination protocols to be established to ensure that patient doses are as low as reasonably achievable, economic and social factors being taken into account especially for chest examinations.

In medical exposure dose to patients are determine by input parameters including mAs, kVp, pitch factor among other factors. The aim of this study is to provide procedure and protocol of how to assess patients’ dose (organ and effective dose) estimates with preset eff mAs and standard kVp. This is to determine a tradeoff between patient’s dose and the image quality before imaging. In addition to providing appropriate clinical recommendation for clinicians for dose management during CT scan. MVL DICOM application software was used to access image data during abdominal CT scan. Organ and effective dose estimates were estimated as developed by ICRP 103 recommendations. Where on the image data, using MVL platform detail information of the mAs, kVp, CTDIvol and DLP were available for recording. The weighted CTDI (CTDIW) was estimated by multiplying the volume CTDI (CTDIVOL) by the pitch factor. Which was used to estimate organ dose using the normalized organ dose factor and the effective dose was estimated by the product of the region-specific normalizing constant and the dose length product. The mAs is the effective Milliameter per second, which were calculated by dividing the mAs by the pitch factor. The relationship between input and output parameters were modeled as the final component of the modeling process in a form of GUI applications format. This was done to establish the various process and procedures involve in abdominal scan for dose managements. The coding process involve the use of written visual basic code to design an interface and integrated on the MVL application platform for clinical application. The GUI has been recommended for use by various stake holders in CT operations.

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.

Medical physics has been an indispensable and strategic stakeholder in the delivery of radiological services to the healthcare system of Ghana. The practice has immensely supported radiation oncology and medical imaging facilities over the years, while the locally established training programme continues to produce human resource to feed these facilities. The training programme has grown to receive students from other African countries in addition to local students. Ghana has been recognised by the International Atomic Energy Agency as Regional Designated Centre for Academic Training of Medical Physicists in Africa. The Ghana Society for Medical Physics collaborates with the School of Nuclear and Allied Sciences of the University of Ghana to ensure that training offered to medical physicists meet international standards, making them clinically qualified. The Society has also worked together with other bodies for the passage of the Health Profession's Regulatory Bodies Act, giving legal backing to the practice of medical physics and other allied health professions in Ghana. The country has participated in a number of International Atomic Energy Agency's projects on medical physics and has benefited from its training courses, fellowships and workshops, as well as those of other agencies such as International Organization for Medical Physics. This has placed Ghana's medical physicists in good position to practice competently and improve healthcare.