Tumors affecting the cribriform plate such as squamous cell carcinomas, meningiomas, and esthesioneuroblastoma or olfactory neuroblastomas; inflammatory lesions such as sarcoidosis and granulomatosis with polyangiitis; and congenital conditions such as cephaloceles and Kallmann syndrome can also result in impaired olfaction [32-34]. Olfactory dysfunction is also associated with neurodegenerative, cognitive, and mood disorders including Alzheimer disease, Parkinson disease, and depression [30,35-38]. CT Head There is no relevant literature to support the use of CT head in the evaluation of the olfactory nerve. CT Maxillofacial CT of the paranasal sinuses and face is useful to evaluate fractures, paranasal sinus inflammatory disease, and bony anatomy that impact olfaction [29,39-41]. CT can be used to characterize sinonasal inflammatory disease. Rhinosinusitis with nasal polyposis severity, as characterized by CT, correlates with worse olfaction [31]. Although the anatomic subunits of the olfactory pathway except for the olfactory bulbs cannot be directly visualized by CT, imaging protocols should cover the major anatomic divisions of the olfactory nerve and pathway, including the olfactory epithelium, which is located in the upper nasal cavity; the olfactory neurons and bulbs, located in the cribriform plate and inferior frontal lobes; and the olfactory pathways, which travel in portions of the temporal and Cranial Neuropathy frontal lobes [4]. No IV contrast is necessary for osseous evaluation including posttrauma and for uncomplicated inflammatory sinonasal disease. Contrast-enhanced CT is useful to evaluate granulomatous and neoplastic disease. There is no relevant literature to support the use of combined pre- and postcontrast imaging. CTA Head There is no relevant literature to support the use of CT angiography (CTA) head in the evaluation of the olfactory nerve.
Cranial Neuropathy. Tumors affecting the cribriform plate such as squamous cell carcinomas, meningiomas, and esthesioneuroblastoma or olfactory neuroblastomas; inflammatory lesions such as sarcoidosis and granulomatosis with polyangiitis; and congenital conditions such as cephaloceles and Kallmann syndrome can also result in impaired olfaction [32-34]. Olfactory dysfunction is also associated with neurodegenerative, cognitive, and mood disorders including Alzheimer disease, Parkinson disease, and depression [30,35-38]. CT Head There is no relevant literature to support the use of CT head in the evaluation of the olfactory nerve. CT Maxillofacial CT of the paranasal sinuses and face is useful to evaluate fractures, paranasal sinus inflammatory disease, and bony anatomy that impact olfaction [29,39-41]. CT can be used to characterize sinonasal inflammatory disease. Rhinosinusitis with nasal polyposis severity, as characterized by CT, correlates with worse olfaction [31]. Although the anatomic subunits of the olfactory pathway except for the olfactory bulbs cannot be directly visualized by CT, imaging protocols should cover the major anatomic divisions of the olfactory nerve and pathway, including the olfactory epithelium, which is located in the upper nasal cavity; the olfactory neurons and bulbs, located in the cribriform plate and inferior frontal lobes; and the olfactory pathways, which travel in portions of the temporal and Cranial Neuropathy frontal lobes [4]. No IV contrast is necessary for osseous evaluation including posttrauma and for uncomplicated inflammatory sinonasal disease. Contrast-enhanced CT is useful to evaluate granulomatous and neoplastic disease. There is no relevant literature to support the use of combined pre- and postcontrast imaging. CTA Head There is no relevant literature to support the use of CT angiography (CTA) head in the evaluation of the olfactory nerve.