MRI Orbits, Face, and Neck Without and With IV Contrast MRI orbits, face, and neck without and with IV contrast has superior soft tissue contrast resolution and with this an improved ability to delineate the soft tissue extent of tumor including the extraglandular extension of disease and perineural spread, which are key components in the T staging of disease and essential for treatment planning. Because of its superior soft tissue contrast resolution, MRI is considered the modality of choice for initial staging of major salivary gland cancer [108,112] relative to CECT. MRI overcomes many of the limitations encountered Assessment of Head and Neck Cancer by US by providing extended cross-sectional anatomic view of the area of interest and allowing for the detection of perineural tumor spread, deep-tissue extension, and marrow involvement [107]. Additionally, MRI may identify signal change and signs of extranodal extension in regional lymph nodes [112]. In the setting of sublingual and submandibular gland tumors, MRI accurately depicts the anatomy of the floor of the mouth, which is imperative in preoperative staging [107]. Because of the increased risk of malignancy of sublingual gland lesions, MRI is the imaging modality of choice [112]. Studies have reported no statistically significant difference in diagnostic accuracy between US, CT, MRI, and PET/CT to distinguish benign from malignant salivary gland tumors [106,113]. However, one meta-analysis showed MRI to have a higher sensitivity and specificity for differentiating between benign and malignant tumors [113]. The addition of advanced MRI techniques including diffusion-weighted imaging and perfusion imaging, such as dynamic contrast-enhanced, may improve the ability of MRI to distinguish benign from malignant salivary gland tumor with reported similar results to fine-needle aspiration [107], although these tools are not consistently used in routine clinical practice.
Staging and Post Therapy Assessment of Head and Neck Cancer. MRI Orbits, Face, and Neck Without and With IV Contrast MRI orbits, face, and neck without and with IV contrast has superior soft tissue contrast resolution and with this an improved ability to delineate the soft tissue extent of tumor including the extraglandular extension of disease and perineural spread, which are key components in the T staging of disease and essential for treatment planning. Because of its superior soft tissue contrast resolution, MRI is considered the modality of choice for initial staging of major salivary gland cancer [108,112] relative to CECT. MRI overcomes many of the limitations encountered Assessment of Head and Neck Cancer by US by providing extended cross-sectional anatomic view of the area of interest and allowing for the detection of perineural tumor spread, deep-tissue extension, and marrow involvement [107]. Additionally, MRI may identify signal change and signs of extranodal extension in regional lymph nodes [112]. In the setting of sublingual and submandibular gland tumors, MRI accurately depicts the anatomy of the floor of the mouth, which is imperative in preoperative staging [107]. Because of the increased risk of malignancy of sublingual gland lesions, MRI is the imaging modality of choice [112]. Studies have reported no statistically significant difference in diagnostic accuracy between US, CT, MRI, and PET/CT to distinguish benign from malignant salivary gland tumors [106,113]. However, one meta-analysis showed MRI to have a higher sensitivity and specificity for differentiating between benign and malignant tumors [113]. The addition of advanced MRI techniques including diffusion-weighted imaging and perfusion imaging, such as dynamic contrast-enhanced, may improve the ability of MRI to distinguish benign from malignant salivary gland tumor with reported similar results to fine-needle aspiration [107], although these tools are not consistently used in routine clinical practice.