Bone marrow for assessing the marrow cavity of bones, although with low sensitivity and specificity. For example, normal fatty "yellow" marrow in adult long bones is of low density (-30 to -100 Hounsfield units), between subcutaneous fat and soft tissue. Tissue with increased cellular composition, such as normal "red" marrow or cancer cells within the medullary cavity will measure variably higher in density. MRI is more sensitive and specific for assessing bone bone composition. MRI enables assessment of the average molecular composition of soft tissues, and thus provides information regarding the relative fat content of marrow. In adult humans, "yellow" fatty marrow
Soft tissue sarcoma in cats and dogs gather as much information as possible regarding the tumor's tissue origin, size, site, histologic grade (level of aggressiveness) and whether it has spread to other organs. To definitively confirm the diagnosis of a soft-tissue sarcoma, the veterinarian will have to perform biopsy for histopathologic evaluation. Additional tests are performed in order to evaluate how advanced the cancer is. These tests generally involve blood and serum biochemical tests, chest X-rays to check for metastasis to the lungs and imaging studies [e.g. ultrasound, computed tomography (CT) or magnetic resonance imaging (MRI)] to evaluate the extent of the disease. There are three main