The patient refuses surgery. While this information may be helpful, a normal CT scan does not rule out the possibility of metastatic disease. Lymph nodes as small as 2 mm have been found to contain metastases with extracapsular spread. Contrast is important in assessing neck disease. Without contrast, discerning pathologic adenopathy can be quite difficult.
Tumor usually enhances more than surrounding muscle because of contrast.
This makes identification of pathology easier. MRI of the neck with gadolinium MRI is superior to CT scan in differentiating soft tissues. This is particularly helpful in assessing the extent of the primary tumor into surrounding soft tissues. In studying lymph node metastases, MRI is as accurate as CT scan, and there is no clear-cut benefit in using either study. Choice of MRI versus CT scan should be based on which will yield the most information about the primary lesion.