What it means
Calcium is the mineral that makes bones hard. It can also settle in soft tissue, often where there was old inflammation, an injury, or slow wear over many years. Calcium blocks X-rays well, so calcifications look bright white on X-ray, CT and mammograms. On ultrasound they look bright and may cast a dark shadow behind them. On MRI they are often hard to see.
When it matters
Most calcifications are harmless leftovers, such as those in old granulomas, the prostate, fibroids or cysts. Calcium in the heart's arteries is a marker of hardened arteries, which your doctor may weigh when judging heart risk. In the breast and thyroid, the size, shape and grouping of tiny calcifications matter, and some patterns lead to extra views or a biopsy.
Questions to ask your doctor
- Is this calcification in a place where it is usually harmless?
- Does its size, shape or pattern suggest anything I should know?
- Does it need any follow-up, or can it be left alone?
