What does radioactive concentration mean

When scanning the human skeleton, especially using bone scans to diagnose bone tumors, the conclusion of radioactive concentration will be drawn. Everyone is familiar with radioactive substances, but many people are not very familiar with radioactive concentration. This thing can even appear in some malignant primary bone tumors, but it can also occur in aseptic necrosis fractures. So, what does radioactivity concentration mean? Let’s take a look below.

Radioactive concentrated foci generally indicate that the blood supply is relatively rich. Such reactions may occur in some patients with increased bone metabolism, bone tumors, bone metastases, and the epiphyseal ends of children. ECT examination can reflect the local metabolic status. The faster the metabolism, the more drugs stay there, and the reaction seen on the film is the concentrated foci.

Various reasons can lead to radioactive accumulation in bone scans , such as old fractures, occult bone injuries, and tumor bone metastasis. Bone scan has high diagnostic sensitivity but poor specificity. Further X-ray examination can be performed and combined with medical history to determine the nature of the lesions in the concentrated area.

The radioactive concentration in the bone scan may indicate a benign lesion, such as bone hyperplasia in the knee joint, or severe bone damage such as fractures. Enhanced MRI can be performed on areas where concentration is indicated to confirm whether there is metastasis.

It just means that there is abundant local blood flow and excessive deposition of calcium phosphate. There are many causes for this, and malignant lesions are just one of them.

Malignant primary bone tumors take up bone imaging agents (radioactive drugs) at a higher rate than normal tissues or benign bone tumors. In the three-phase bone imaging, the arterial phase may show early filling, the blood pool phase shows local congestion, and the delayed phase shows abnormal local radioactivity concentration. Among the malignant primary bone tumors, osteosarcoma, Ewing's sarcoma and chondrosarcoma are the most malignant. Bone scintigraphy has a high diagnostic value, but the type of tumor requires a comprehensive analysis based on age, lesion site, number of lesions, and morphology of the scintigraphy. Extraosseous metastases of some primary bone tumors (usually lung metastases) can also concentrate bone imaging agents. Bone imaging is much more sensitive than X-ray diagnosis for the diagnosis of lung metastases of osteosarcoma.

For primary bone tumors characterized by osteolytic changes, such as multiple myeloma , there is no significant increase in the uptake of imaging agents by the diseased tissue, so the diagnostic sensitivity is lower than that of X-ray examination. Generally speaking, bone imaging shows that the range of lesions is larger than that shown on X-rays. For confirmed primary bone tumors, bone imaging can show the range of abnormal bone metabolism, which is helpful for formulating surgical plans, rationally arranging the size of the radiotherapy field, and estimating the effect after treatment.