Temporal bone CT with IV contrast may be complementary to MRI and is useful for characterizing osseous changes of the skull base and neural foramina and may be useful to characterize perineural fat planes; however, contrast-enhanced neck CT with thin-cut high-resolution bone algorithm windows through the skull base can provide similar information while simultaneously staging the neck [64,66]. There is no relevant literature to support the use of combined pre- and postcontrast imaging. CT Neck MRI has better sensitivity for detection of perineural spread of tumor compared with CT and is the preferred study for initial assessment of perineural spread of tumor [65]. The trigeminal (CN V) and facial (CN VII) nerves are most commonly affected by perineural tumor spread and have branches extending into the face and neck. Neck CT may be complementary to MRI and is useful for characterizing osseous changes of the skull base and neural foramina and may be useful to characterize perineural fat planes while simultaneously staging the neck [64,66]. Contrast should be administered. There is no relevant literature to support the use of combined pre- and postcontrast imaging. CTA Head and Neck There is no relevant literature to support the use of CTA head and neck in the initial evaluation of perineural spread of tumor. FDG-PET/CT Skull Base to Mid-Thigh FDG-PET/CT is not routinely used in the initial evaluation of the perineural spread of tumor, although perineural tumor spread may be detected on metabolic imaging. FDG-PET/CT may be useful for staging and response assessment in patients with a known primary malignancy [195,197]. Contrast-enhanced PET/MR may detect perineural spread of a tumor and may be useful as an alternate to PET/CT in the evaluation of patients with head and neck cancers [164]. MRA Head and Neck There is no relevant literature to support the use of MRA in the initial evaluation of perineural spread of tumor.
Cranial Neuropathy. Temporal bone CT with IV contrast may be complementary to MRI and is useful for characterizing osseous changes of the skull base and neural foramina and may be useful to characterize perineural fat planes; however, contrast-enhanced neck CT with thin-cut high-resolution bone algorithm windows through the skull base can provide similar information while simultaneously staging the neck [64,66]. There is no relevant literature to support the use of combined pre- and postcontrast imaging. CT Neck MRI has better sensitivity for detection of perineural spread of tumor compared with CT and is the preferred study for initial assessment of perineural spread of tumor [65]. The trigeminal (CN V) and facial (CN VII) nerves are most commonly affected by perineural tumor spread and have branches extending into the face and neck. Neck CT may be complementary to MRI and is useful for characterizing osseous changes of the skull base and neural foramina and may be useful to characterize perineural fat planes while simultaneously staging the neck [64,66]. Contrast should be administered. There is no relevant literature to support the use of combined pre- and postcontrast imaging. CTA Head and Neck There is no relevant literature to support the use of CTA head and neck in the initial evaluation of perineural spread of tumor. FDG-PET/CT Skull Base to Mid-Thigh FDG-PET/CT is not routinely used in the initial evaluation of the perineural spread of tumor, although perineural tumor spread may be detected on metabolic imaging. FDG-PET/CT may be useful for staging and response assessment in patients with a known primary malignancy [195,197]. Contrast-enhanced PET/MR may detect perineural spread of a tumor and may be useful as an alternate to PET/CT in the evaluation of patients with head and neck cancers [164]. MRA Head and Neck There is no relevant literature to support the use of MRA in the initial evaluation of perineural spread of tumor.