A mammogram is a specialized X-ray screening tool used to create detailed images of the breast tissue. This procedure is standard practice for the early detection of breast changes, which can include signs of breast cancer. To ensure the images captured are clear and interpretable by the radiologist, patients are instructed to avoid applying any products to the underarm and breast area before the exam. Strict compliance with this request is necessary to achieve the highest possible accuracy for the screening results.
The Chemical Reason for X-Ray Interference
The prohibition against using certain personal care products stems from their chemical composition and the physics of X-ray imaging. Many antiperspirants, deodorants, and body powders contain metallic compounds, most commonly aluminum, often in the form of aluminum chlorohydrate or aluminum zirconium. These substances are intentionally opaque to X-rays, a property known as radio-opacity.
When a product containing these metallic salts is applied to the skin, even a small amount of residue will absorb the X-ray radiation. This absorption prevents the X-rays from passing through to the detector plate behind the breast. Consequently, the areas where the product was applied appear as bright white spots on the resulting mammogram image.
This effect is similar to how a bone or a medical clip appears white on an X-ray, demonstrating its density. Even some natural products or body powders can contain other minerals, like talc or baking soda, which may also be dense enough to interfere with the low-energy X-rays used in the procedure. The presence of these dense, radio-opaque particles on the image can compromise the clarity required for a diagnostic reading.
How Artifacts Can Mimic Suspicious Findings
The white spots created by deodorant residue are known as imaging “artifacts,” and they pose a significant diagnostic challenge for the interpreting radiologist. These artifacts can often appear in the axilla, or armpit, region and may also be smeared onto the compressed breast tissue. The major concern is that these false white spots look almost identical to true microcalcifications.
Microcalcifications are tiny calcium deposits that sometimes form within the breast tissue. While most microcalcifications are benign, certain patterns—such as fine, linear, or clustered groupings—can represent an early indication of ductal carcinoma in situ, a non-invasive form of breast cancer. The radiologist must be able to distinguish between a harmless product residue and these medically significant calcifications.
When artifacts are present, they create diagnostic confusion, making it difficult to rule out a true abnormality. This ambiguity frequently leads to a “call-back,” where the patient must return for additional, unnecessary imaging. This need for repeat testing increases patient anxiety and can delay the final, accurate interpretation of the screening.
Practical Steps for Procedure Preparation
Proper preparation on the day of the appointment is simple and focuses on ensuring the skin is completely clean and clear of any external substances. All products applied to the breast or underarm area must be avoided, including deodorants, antiperspirants, body powders, skin creams, and lotions. The goal is to remove any residue that could potentially create an artifact on the image.
If a patient forgets and applies a product, they should inform the technologist immediately upon arrival. Most mammography facilities maintain a supply of mild soap, water, or specialized cleansing wipes for this purpose. The technologist will provide instructions and materials to thoroughly clean the underarm and breast area before the examination begins.
To prevent issues, showering before the appointment and avoiding the use of products afterward is the most reliable strategy. Patients who are concerned about odor can bring their deodorant or antiperspirant with them and apply it immediately after the imaging procedure is complete. This simple step ensures the highest quality image is obtained on the first attempt, preventing the need for a second visit.