Introduction: The accuracy of image interpretations of CT and MRI studies is absolutely dependent on the quality of the images produced. Motion artifacts which result from the patients' movement during image acquisitions may lead to misinterpretation, wrong diagnosis or inconclusive examinations. In pediatric age groups, most of CT and MRI examinations require sedation or general anesthesia to achieve the degree of cooperation or immobilisation to complete the procedures successfully. Methods: The patients were randomly chosen among children, from newborn to 12 years of age who underwent sedation and general anesthesia for CT scan and and MRI in the University of Malaya Medical Centre between September 2001 and August 2003. The quality of MRI and CT images were evaluated by radiologists using a three-point scale: 1-no motion artifact; 2-minor motion artifacts and 3-major motion artifacts. Results: Among sedated children, 75.5% and 41% had good CT and MRI images respectively. In general, the anesthesia group, 100% had good CT images and 85.7% had good MRI images. Children who received sedation (33.5%) had severe motion artifacts whereas none of the anesthetised children had severe motion artifacts. Conclusion: General anesthesia is much better for good quality images in both MRI and CT examinations; however it is associated with a higher cost and longer hospital stay. Combination of oral chloral hydrate and intravenous midazolam was found to be the most effective sedative agent in terms of CT/MRI image quality.

In the practice of forensic entomology, the chronological age of the maggots retrieved from the cadaver is used to determine the minimum post-mortem interval (mPMI) i.e. minimum time of death. The conventional method of aging the maggots is based on measuring the growth rate of these maggots. Although effective, the constraint associated with conventional method necessitates the development of new age determination method, such as pteridine determination. Pteridine, a by-product of protein metabolism in insects is known to correlate with the age of a variety of dipterans. A number of studies were conducted on aging the adults of forensically important flies. In this study, pteridine was extracted from Chrysomya megacephala and Chrysomya rufifacies maggots of known age using established methods and determined by measuring the fluorescence at excitation of 330nm and the emissions between 350nm and 600nm. Results exhibited significant positive linear relationships between the pteridine accumulations and age of the fly immature. Pteridine determination is a potential new age determination tool that can be used to determine mPMI.