Monte Carlo radiography simulation for assessment of absorbed radiation dose in femur bone marrow during X-ray radiography for constant mAs and AEC techniques

The purpose of this study was to find the accurate absorbed dose in the femur bone marrow during the X-ray radiography for constant mAs and AEC techniques. The DOSXYZnrc was used to simulate radiation doses in two human femurs during diagnostic radiography. EGSnrc phantoms produced from actual CT images of human femurs were modified by adding seven micrometre layers of marrow tissues. The X-ray machine was simulated using BEAMnrc using 30 billions particles for different combinations of energies and filters. The resultant data was used to in DOSXYSnrc simulations to evaluate the absorbed dose in the human femur. In the head of the femur, for 2.5 mm aluminium filtered 85 kVp X-ray set at 50 mAs, the absorbed dose in the marrow was found to be 1.360 mGy, tilde 36% of the absorbed dose in the cortical bone. It was also found that for the constant mAs technique, the radiation dose in the marrow over the studied energies and filter combination, ranges from 0.356 mGy to 2.403 mGy, with higher dose recorded for higher kVp settings. However, for the AEC technique, the dose is lower for higher kVp settings. For a typical setting, viz. 85 kVp, 6 mAs at 48 inches SID, the bone marrow absorbed dose was found to be 0.186 mGy for the constant mAs technique and 0.0308 mGy for the AEC technique. It was confirmed that the radiation dose is lower when the AEC exposure technique is used as opposed to using constant mAs technique. For the AEC technique, typical dose to the bone marrow was found to be tilde 0.05 mGy, decreasing with both kVp settings and beam filtration. For constant mAs technique, the typical dose to bone marrow is found to be higher, tilde 0.2 mGy, decreasing with the amount of filtration used but increasing with the kVp setting

Ocular disorders among schoolchildren in Khartoum State, Sudan

From December 2005 to June 2007, a total screening of all 1418 government primary schools in Khartoum State, Sudan, was performed to estimate ocular problems among children aged 6-15 years. We screened 671 119 children [56.7% males] for significant refractive error and other eye ailments. Ocular problems were found in 20 321 [3.03%] children. The 3 localities with highest ocular pathology were Karary [26.2%], Ummbada [21.0%] and Jabal Awlia [15.7%]. The overall prevalence of refractive error was 2.19%. Myopia was found in 10 064 [1.50%] children while 4661 [0.70%] were hyperopic. Other ocular problems included vernal keratoconjunctivitis, vitamin A deficiency, microbial conjunctivitis, strabismus and corneal opacity. Only 288 [0.04%] children were diagnosed with active trachoma: 86.5% of these were from Ummbada locality, on the periphery of the State, where transportation facilities are poor and poverty is widespread. Overall, 99% of the eye ailments identified are either treatable or preventable. To reduce these and to achieve the goals of Vision 2020, an effective and efficient school health programme is needed

Pattern of morbidity and mortality in Karbala hospitals during Ashura mass gathering at Karbala, Iraq, 2010

Religious mass gatherings are increasingly common in Iraq and can harbour considerable public health risks. This study was aimed at determining morbidity and mortality patterns in hospitals in Karbala city, Iraq during the mass gathering for Ashura in 2010. We conducted a cross-sectional study on attendees at the 3 public hospitals in the city. The study period was divided into pre-event, event, and post-event phases. Morbidity and mortality data were obtained from hospital registry books and the coroner's office. About 80% of the 18 415 consultations were at emergency rooms. Average daily emergency room attendance was higher during the event compared with pre- and post-event phases, while average daily admissions decreased. Compared with the pre-event phase, a 7-fold increase in febrile disorders and a 2-fold increase in chronic diseases and injuries were noted during the event phase. There was no difference between the 3 phases for average daily death rate,nor for cause of death

new spectrophotometric method for the determination of methyldopa

A new, simple and low cost spectrophotometric method for the determination of methyldopa in pharmaceutical preparations was developed. The method was based on the coupling of methyldopa with 2,6-dichloroquinone-4-chlorimide [DCQ]. The absorbance maximum [lambda max] of the resulted colored product was at 400nm. Different buffers were used to determine the optimal pH for the reaction. 1% w/v acetate buffer with pH 8.0 gave the optimal pH required for the reaction. Of the different solvents tried, water and ethanol were found to be the most suitable solvents. Beer's law was obeyed in concentration range of 4-20 micro g/ml methyldopa. The correlation coefficient was found to be [r=0.9975]. The limit of detection and limit of quantification were 1.1 micro g/ml and 3.21 micro g/ml, respectively. The reaction ratio between methyldopa and DCQ was studied and found to be 1:3. The work included the study of the possible interference of hydrochlorothiazide found in combination with methyldopa tablets. The method was validated and results obtained for the assay of two different brands of methyldopa tablets were compared with the B.P. method [colorimetric]. The repeatability and reproducibility of the developed method were evaluated and the obtained results quoted. The derivative formed as a result of the reaction of methyldopa with DCQ was isolated and its possible mechanistic pathway was suggested

Are Indians and females less tolerant to pain? An observational study using a laboratory pain model

In Malaysia, it is a common belief among health care workers that females and Indians have lower pain threshold. This experience, although based on anecdotal experience in the healthcare setting, does not allow differentiation between pain tolerance, and pain expression. To determine whether there is a difference in the tolerance to pain between the three main ethnic groups, namely the Malays, Chinese and Indians as well as between males and females. This was a prospective study, using a laboratory pain model (ischaemic pain tolerance) to determine the pain tolerance of 152 IMU medical students. The mean age of the students was 21.8 years (range 18-29 years). All of them were unmarried. The median of ischaemic pain tolerance for Malays, Chinese and Indians were 639s, 695s and 613s respectively (p = 0.779). However, statistically significant difference in ischaemic pain tolerance for males and females Indian students were observed. Possible ethnic difference in pain tolerance in casual observation is not verified by this laboratory pain model. Difference in pain tolerance between genders is shown only for Indians.