Punctate foci are focal points of tiny spots or depressions. Punctate foci are seen in radiology exam results and denote the presence of possible disease. Punctate foci are commonly seen in the spine and brain.
Punctate foci of the bone generally occur in the central spinal column and skull, and they are occasionally found on the longer bones of the body. While they are generally benign, approximately 1 percent of punctate foci of the bone are malignant, according to Medscape.
Punctate foci lesions found in the brain, however, can be a sign of possible multiple sclerosis. These lesions are seen during an MRI scan of the brain and show up as pinpoint lesions within the white matter. They may also be seen in the spinal cord and other areas of the central nervous system.