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21 November 2009

Answer to Question #1443 Submitted to "Ask the Experts"

Category: Medical and Dental Patient Issues — Diagnostic X Ray and CT

The following question was answered by an expert in the appropriate field:

What does an artifact on an x ray mean? The first x ray (without sedation) showed a mass on the lymph nodes. The next x ray showed everything was fine. The doctor said the first one was an artifact.

In basic terms, an "artifact" on a diagnostic x-ray image is an area of the image that may look different from expected, although it is not necessarily something dealing with what is being imaged. An artifact may appear as light or dark spots, lines, fogging, specks, etc. They can be caused by motion, dirt on film, poor chemistry in a film processor, poor contact between the film and the cassette that holds the film, and so on. Types of artifacts may vary with the modality, for example, plain x-ray film, CT, or ultrasound, but the physician who interprets the image tries to make sure that false positive and false negative results are avoided. Ideally, the physician wants an image that contains no artifacts and, in some cases, will ask that a study be repeated to eliminate an artifact. Ken "Duke" Lovins, MS, CHP Health Physicist

Answer posted on 13 December 2001. The information and material posted on this Web site is intended as general reference information only. Specific facts and circumstances may alter the concepts and applications of materials and information described herein. The information provided is not a substitute for professional advice and should not be relied upon in the absence of such professional advice specific to whatever facts and circumstances are presented in any given situation. Answers are correct at the time they are posted on the Web site. Be advised that over time, some requirements could change, new data could be made available, or Internet links could change. For answers that have been posted for several months or longer, please check the current status of the posted information prior to using the responses for specific applications.