Hyperdense foci are medical imaging findings that may be caused by calcification, tumors, or other conditions at the site of the lesion. If there is localized calcification, it is mostly caused by inflammation. When the inflammation in the lesion site is prolonged, inflammatory factors may be released, which may lead to calcium salt deposition and the formation of calcification, and high density foci will appear in the examination. If the examination site has a tumor, including benign tumors and malignant tumors, the tumor has more fibrous connective tissue, and the texture of the tumor is harder, and the density of the tumor is different from that of the surrounding normal tissues, which will also lead to the occurrence of high-density foci during the imaging examination. When high density foci are found in imaging examination, further examination should be carried out, and when it is suspected to be a tumor, pathological biopsy can be carried out in cooperation with the doctor to clarify the nature of the lesion, and treatment can be carried out according to the cause of the lesion. Regular review should also be conducted to understand the changes of the disease.