Abstract
A retrospective analysis of 65 patients with extracranial tumors of the head and neck was conducted on findings from computed tomography (CT), magnetic resonance imaging (MRI) and clinical records.
MRI was equal or superior to CT in all cases except five. MRI easily surpassed CT in its ability to differentiate subtle differences in soft tissue boundaries and tumor invasion in the head and neck. MRI also hasa number of advantages to the patients: no ionizing irradiation hazards and no need for any intravenous contrast. MRI can depict cross-sectional anatomy in orthgonal planes without requiring patient manipulation. The beem hardening artifacts are also not on CT images from dental amalgam. Replacing normal bone marrow with tissve of a high water content produced lower signeals on T1W images and higher signals on T2W images. Since this signal pattern is most frequently seen with focal metastatic tumors, MRI may be helpful in detecting bone marrow invasion as well.
There are, however, some limitations in using MRI in the head and neck. Large tumors may inhibit imaging due to motion artifacts from repeated swallowing. MRI is inferior to CT in its representation of micro-calcifications in cases with thyroid cancer. Despite these drawbacks, however, MRI should serve as a premiere imaging modality for most head and neck disease because of its far greater soft tissue contrast potential.
