Pathology of the Trigeminal Nerve
Imaging of the trigeminal nerve requires a thorough understanding of its anatomy and function, clinical symptoms related to malfunction, and its key pathologies. Because of the nerve’s long course from…
Pathology of the Ocular Motor Nerves III, IV, and VI
The ocular motor nerves supply motor fibers to the extraocular muscles of the globe and levator muscle of the eyelid and parasympathetic pupillomotor fibers to the ciliary ganglion. Lesions are…
Pathology of the Olfactory Nerve
The olfactory system and especially the olfactory bulb (OB) as the first relay in the olfactory system represent highly plastic structures. For example, OB volume partly reflects the degree of…
Pathology of the Optic Nerve
This article focuses on pathologic processes affecting the optic nerve, optic nerve/sheath complex, and chiasm. Pathology of the visual pathways posterior to the chiasm is beyond the scope of this article…
Arterial Vascularization of the Cranial Nerves
We discuss the arterial supply of the cranial nerves from their exit out of the brain stem to their exit from the skull base. Four distinct groups can be differentiated…
Perineural Tumor Spread
Perineural spread (PNS) refers to the extent of tumor cells or other nonneoplastic lesions along the tissues of the nerve sheath, its overall incidence ranges from 2.5% to 5%. PNS…
Denervation Atrophy of Motor Cranial Nerves
Muscles undergoing denervation demonstrate a variety of imaging appearances in the various stages. It is incumbent on the radiologist to be aware of these changes so as not to interpret…
MRI of the Cranial Nerves—More than Meets the Eye: Technical Considerations and Advanced Anatomy
Magnetic resonance (MR) imaging is the method of choice to evaluate the cranial nerves. Although the skull base foramina can be seen on CT, the nerves themselves can only be…
Pathology of the Olfactory Nerve
The olfactory system and especially the olfactory bulb (OB) as the first relay in the olfactory system represent highly plastic structures. For example, OB volume partly reflects the degree of…
Ultrasound of Thyroid Nodules
Thyroid nodules can be detected in 4% to 8% of the adult population by palpation, but in 40% to 50% of the population by ultrasound. The overwhelming majority of these…
