ABSTRACT
Background: The role of Computed Tomography (CT) in the medical diagnosis of diseases has greatly expanded, despite the potential risk of cancer following exposures to ionising radiation (X-Ray) from this modality. This risk is particularly of great concern in children, who are more radiosensitive and have many years to manifest radiation effect than adults. Aims: To estimate risk of cancer induction from Pediatric cranial CT. Materials and Methods: A total of 203 patients, who were referred from various pediatric clinics and wards for cranial CT in a teaching hospital in the South Western Nigeria between the year 2011 and 2013 were considered. All patients were grouped into four age (year) groups: less than 1, 1-5, 5-10 and 10-15. A mathematical method was used to estimate the risk of cancer from the effective dose(ED) calculated from volume computed tomography dose index (CTDIvol), dose length product (DLP) and standard conversion factor. Results: The range of CTDIvol (mGy) received by all patients was 10–250 mGy while majority of the patients received 50–100. The range of DLP (mGy.cm) received by all patients and majority of patients was 500–5000 and 2001–2500 respectively. The range of ED (mSv) received by all patients and majority of the patients was 1–25 and 5–10 respectively. The risk estimated with respect to patients’ age showed that patient in the age group 1–5 years have the highest risk of cancer induction while the risk based on gender showed no significant difference. Conclusion: Over 60% of pediatric patients received more than the recommended values of CTDIvol, DLP and ED from cranial CT. Urgent steps must be taken to ensure compliant with international recommended precautions for dose reduction in pediatric medical imaging.
ABSTRACT
Aim: To determine the prevalence of cholelithiasis in Nigerians with sickle cell disease in steady state, using ultrasonography. Study Design: A prospective cross-sectional study. Place and Duration of Study: Haematology Clinic, University of Benin Teaching Hospital, Benin City and Sickle Cell Centre, Benin City, Nigeria between July and December 2011. Methodology: The study population was made up of non-pregnant sickle cell disease patients not in crisis and who have not had cholecystectomy. They were confirmed to have sickle cell disease through haemoglobin electrophoresis. All the patients were examined with a B-mode ultrasound machine with a curvilinear multifrequency transducer 2.5-7.5MHZ after an overnight or at least six hour fast. Calculi were diagnosed if highly echogenic structures, with acoustic shadowing were detected in the lumen of the gallbladder. Results: There were 79 females and 71 males, aged between 10 months and 51 years. Of the 150 patients, 140 were homozygous for sickle cell disease (HbSS), while the remaining 10 were heterozygous for sickle cell disease (HbSC). The prevalence of cholelithiasis was 16.0%. It was related to age, sex and haemoglobin genotype. There was progressive increase in cholelithiasis with age which was more pronounced in the third and fourth decades. Cholelithiasis was also significantly more commonly seen in the HbSS group 23 (16.4%) out of 140 patients compared with the HbSC group 1 (10.0%) out of 10 patients. Cholelithiasis did not correlate with sex, although it was more commonly observed in females. The youngest patient with gall stones in this study was 2 years. Conclusion: The prevalence of cholelithiasis in Nigerians with sickle cell disease was 16.0% and it was related to age and haemoglobin genotype.