Two disadvantages of a CT scan are radiation exposure and the potential for allergic reaction to contrast dye.
Disadvantages of CT Scans Explained
CT scans, while valuable diagnostic tools, do have drawbacks. The two most significant are related to radiation and contrast dye.
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Radiation Exposure: CT scans use X-rays to create detailed images. This means patients are exposed to ionizing radiation. While the level of radiation from a single CT scan is generally considered low, the cumulative effect of multiple scans over time can increase the risk of developing cancer later in life. The risk is higher for children, as they are more sensitive to radiation. Efforts are always made to use the lowest radiation dose possible while still obtaining diagnostic-quality images.
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Allergic Reaction to Contrast Dye: Many CT scans require the use of contrast dye to enhance the images. This dye, typically iodine-based, is injected into the bloodstream. Some individuals are allergic to iodine or other components of the contrast dye. Allergic reactions can range from mild (itching, rash) to severe (difficulty breathing, anaphylaxis). Patients with known allergies to iodine, shellfish, or previous contrast dye reactions should inform their doctor before the scan. Pre-medication with antihistamines or steroids may be necessary to prevent or reduce the severity of an allergic reaction. Additionally, contrast dye can sometimes affect kidney function, particularly in individuals with pre-existing kidney problems.
