Ct scan radiation risk and young patients - Article Example

CT machines have become much faster, and now, it is possible to scan any body part in very less time. The image quality that is on offer is also much better than the older generation of CT machines. At present, the latest multi-slice CT scan machine can accumulate data at around 350 ms. Within less than a second, it is possible for the CT scan machine to use millions of data points and then reconstruct a 512 x 512-matrix image from this. CT scan is among the best and fastest, non-invasive investigative modality for the evaluation of the abdomen, pelvis and chest, and gives a well-defined, cross-sectional view.

CT scan is ideal in the diagnosis of cancer of various organs including the liver, pancreas, lung etc, and allows the surgeon to identify a tumor, including its size, location and how much it has spread to adjacent tissue. Among its other uses include the diagnosis and treatment of vascular diseases, pulmonary embolism and abdominal aortic aneurysms, skeletal lesions etc. CT is also widely used in children, in the evaluation of various tumors of the body like neuroblastoma, lymphoma etc and in the imaging of the kidneys.

However, when compared to conventional radiography, the use of CT involves much higher doses, and there is a risk of radiation. Many studies have been published about this issue, especially the risk in children. Children are more radiosensitive to radiation exposure when compared to adults. It is estimated that children are ten times more sensitive to effect of radiation than middle- aged adults. Children have more time to develop a radiation-induced cancer due to a longer life-expectancy when compared to adults.

It has also been shown that there is an increased dose per milliampere-second, and an increased lifetime risk per unit dose. It has been estimated that in a 1-year-old child, the lifetime cancer mortality risks due to CT scan radiation exposure is around 0.07% (for a head scan) and around 0.18% (for an abdominal scan). This amount of radiation exposure is much higher than what an adult would be exposed to. Another major concern is the trend to use multiple scans. It is felt that when compared to just one scan, two to three scans could theoretically double or triple the risk of cancer.

Sometimes, during a single examination, more than one scan would be done, which increases the radiation dose further. Thus, in the vast majority of cases, a single scan should be enough. Many studies have provided information that there is link between high dose radiation and the development of malignant tumors in children. In February 2001, the American Journal of Roentgenology was among the first journals to publish the risk of radiation in a young patient after a CT scan. It is also quite common nowadays to use CT as a screening technique even for minor complaints like headache, and this has added to the controversy.

  One large study has estimated that on an average, a child would be asked to get a CT scan seven times by the age of eighteen. It has been estimated that in the US alone, about 5 million CT scans are being performed in pediatric patients annually. Another concern is the excessive use of CT scans as a screening tool in patients who are asymptomatic. Due to all these concerns, there is a pressing need to avoid excess radiation dose from CT scanning and optimize the CT scan protocols, especially in young patients.

The risk to benefit should always be considered and alternatives to CT scan like MRI or ultrasound should be