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Clinical Radiology Feb 2013The trigeminal nerve is the largest cranial nerve and has both sensory and motor components. Due to its extensive distribution in the head and neck, the nerve or its... (Review)
Review
The trigeminal nerve is the largest cranial nerve and has both sensory and motor components. Due to its extensive distribution in the head and neck, the nerve or its branches may be involved by a myriad of disease entities. Additionally, the nerve may act as a route of spread in various inflammatory and neoplastic diseases, underlining the need for a thorough understanding of its anatomy. A segmental division of the trigeminal system is preferred when interpreting imaging studies as both the type of lesion and symptoms may vary based on the site of involvement. These segments include the brainstem, cisternal, Meckel's cave, cavernous sinus, and peripheral divisions. In general, dedicated magnetic resonance imaging (MRI) is preferred to evaluate nerve dysfunction. In select cases, contrast medium administration, heavily T2-weighted sequences, or MR angiography may prove to be diagnostic. This review aims to review the anatomy of the trigeminal nerve briefly, followed by illustrations of various lesions that may present with trigeminal nerve dysfunction.
Topics: Contrast Media; Cranial Nerve Neoplasms; Diagnosis, Differential; Female; Humans; Image Enhancement; Magnetic Resonance Imaging; Male; Trigeminal Nerve; Trigeminal Nerve Diseases
PubMed: 22889460
DOI: 10.1016/j.crad.2012.05.019 -
Headache May 2019The goal of this narrative review is to provide an overview of migraine pathophysiology, with an emphasis on the role of calcitonin gene-related peptide (CGRP) within... (Review)
Review
OBJECTIVE
The goal of this narrative review is to provide an overview of migraine pathophysiology, with an emphasis on the role of calcitonin gene-related peptide (CGRP) within the context of the trigeminovascular system.
BACKGROUND
Migraine is a prevalent and disabling neurological disease that is characterized in part by intense, throbbing, and unilateral headaches. Despite recent advances in understanding its pathophysiology, migraine still represents an unmet medical need, as it is often underrecognized and undertreated. Although CGRP has been known to play a pivotal role in migraine for the last 2 decades, this has now received more interest spurred by the early clinical successes of drugs that block CGRP signaling in the trigeminovascular system.
DESIGN
This narrative review presents an update on the role of CGRP within the trigeminovascular system. PubMed searches were used to find recent (ie, 2016 to November 2018) published articles presenting new study results. Review articles are also included not as primary references but to bring these to the attention of the reader. Original research is referenced in describing the core of the narrative, and review articles are used to support ancillary points.
RESULTS
The trigeminal ganglion neurons provide the connection between the periphery, stemming from the interface between the primary afferent fibers of the trigeminal ganglion and the meningeal vasculature and the central terminals in the trigeminal nucleus caudalis. The neuropeptide CGRP is abundant in trigeminal ganglion neurons, and is released from the peripheral nerve and central nerve terminals as well as being secreted within the trigeminal ganglion. Release of CGRP from the peripheral terminals initiates a cascade of events that include increased synthesis of nitric oxide and sensitization of the trigeminal nerves. Secreted CGRP in the trigeminal ganglion interacts with adjacent neurons and satellite glial cells to perpetuate peripheral sensitization, and can drive central sensitization of the second-order neurons. A shift in central sensitization from activity-dependent to activity-independent central sensitization may indicate a mechanism driving the progression of episodic migraine to chronic migraine. The pathophysiology of cluster headache is much more obscure than that of migraine, but emerging evidence suggests that it may also involve hypersensitivity of the trigeminovascular system. Ongoing clinical studies with therapies targeted at CGRP will provide additional, valuable insights into the pathophysiology of this disorder.
CONCLUSIONS
CGRP plays an essential role in the pathophysiology of migraine. Treatments that interfere with the functioning of CGRP in the peripheral trigeminal system are effective against migraine. Blocking sensitization of the trigeminal nerve by attenuating CGRP activity in the periphery may be sufficient to block a migraine attack. Additionally, the potential exists that this therapeutic strategy may also alleviate cluster headache as well.
Topics: Animals; Calcitonin Gene-Related Peptide; Humans; Migraine Disorders; Neuroglia; Neurons; Nociception; Trigeminal Ganglion; Trigeminal Nerve
PubMed: 30982963
DOI: 10.1111/head.13529 -
Topics in Magnetic Resonance Imaging :... Jun 1996The trigeminal nerve is described in terms of segmental anatomy and regional pathology. The common brain stem lesions are neoplasms, vascular disease, and demyelinating... (Review)
Review
The trigeminal nerve is described in terms of segmental anatomy and regional pathology. The common brain stem lesions are neoplasms, vascular disease, and demyelinating processes. Common lesions affecting the cisternal segment and Meckel's cave are schwannoma, meningioma, epidermoid, vascular ectasia, and aneurysm. Common lesions affecting the cavernous segment include meningioma, trigeminal schwannoma, lymphoma, metastasis, and vascular lesions. Skull base abnormalities include chordoma, chondrosarcoma, metastasis, bone dysplasias, and Paget's disease. The peripheral divisions of the trigeminal nerve are commonly involved by adjacent inflammatory disease in the sinuses, perineural spread of malignancy, and schwannoma. Unfortunately, the anatomic site of a lesion cannot be accurately predicted on the basis of clinical symptomatology. Successful imaging evaluation must include the entire course of the trigeminal nerve from the brain stem and upper cervical cord through the peripheral branches.
Topics: Aged; Aged, 80 and over; Brain Neoplasms; Cranial Nerve Diseases; Cranial Nerve Neoplasms; Humans; Magnetic Resonance Imaging; Tomography, X-Ray Computed; Trigeminal Nerve
PubMed: 8840469
DOI: No ID Found -
Seminars in Ultrasound, CT, and MR Oct 2022The trigeminal nerve is the fifth cranial nerve and is a sensory-motor nerve that provides the innervation to the face with its three roots. The trigeminal nerve can be...
The trigeminal nerve is the fifth cranial nerve and is a sensory-motor nerve that provides the innervation to the face with its three roots. The trigeminal nerve can be affected by several diseases, such as vascular conflict, congenital malformation, inflammatory or neoplastic diseases. Magnetic Resonance Imaging plays a crucial role in its evaluation. This article aims to review the trigeminal nerve anatomy, discuss the best magnetic resonance imaging techniques to evaluate each nerve segment, and demonstrate the imaging aspect of the diseases that most commonly affect it.
Topics: Humans; Magnetic Resonance Imaging; Trigeminal Nerve
PubMed: 36116853
DOI: 10.1053/j.sult.2022.04.002 -
Journal of Neuroscience Research Aug 2023
Review
Topics: Humans; Trigeminal Ganglion; Trigeminal Nerve; Trigeminal Neuralgia
PubMed: 36977654
DOI: 10.1002/jnr.25192 -
European Journal of Radiology May 2010Of all cranial nerves, the trigeminal nerve is the largest and the most widely distributed in the supra-hyoid neck. It provides sensory input from the face and motor... (Review)
Review
Of all cranial nerves, the trigeminal nerve is the largest and the most widely distributed in the supra-hyoid neck. It provides sensory input from the face and motor innervation to the muscles of mastication. In order to adequately image the full course of the trigeminal nerve and its main branches a detailed knowledge of neuroanatomy and imaging technique is required. Although the main trunk of the trigeminal nerve is consistently seen on conventional brain studies, high-resolution tailored imaging is mandatory to depict smaller nerve branches and subtle pathologic processes. Increasing developments in imaging technique made possible isotropic sub-milimetric images and curved reconstructions of cranial nerves and their branches and led to an increasing recognition of symptomatic trigeminal neuropathies. Whereas MRI has a higher diagnostic yield in patients with trigeminal neuropathy, CT is still required to demonstrate the bony anatomy of the skull base and is the modality of choice in the context of traumatic injury to the nerve. Imaging of the trigeminal nerve is particularly cumbersome as its long course from the brainstem nuclei to the peripheral branches and its rich anastomotic network impede, in most cases, a topographic approach. Therefore, except in cases of classic trigeminal neuralgia, in which imaging studies can be tailored to the root entry zone, the full course of the trigeminal nerve has to be imaged. This article provides an update in the most recent advances on MR imaging technique and a segmental imaging approach to the most common pathologic processes affecting the trigeminal nerve.
Topics: Humans; Magnetic Resonance Imaging; Tomography, X-Ray Computed; Trigeminal Nerve; Trigeminal Nerve Diseases
PubMed: 20227216
DOI: 10.1016/j.ejrad.2010.02.006 -
Journal of Neurosurgery Apr 2005
Topics: Cerebellum; Humans; Magnetic Resonance Imaging; Motor Neurons; Terminology as Topic; Trigeminal Nerve
PubMed: 15871523
DOI: 10.3171/jns.2005.102.4.0758 -
Clinical Anatomy (New York, N.Y.) Jan 2014The objective of this study is to review surgical anatomy of the trigeminal nerve. We also demonstrate some pictures involving the trigeminal nerve and its surrounding... (Review)
Review
The objective of this study is to review surgical anatomy of the trigeminal nerve. We also demonstrate some pictures involving the trigeminal nerve and its surrounding connective and neurovascular structures. Ten adult cadaveric heads were studied, using a magnification ranging from 3× to 40×, after perfusion of the arteries and veins with colored latex. The trigeminal nerve is the largest and most complex of the cranial nerves. It serves as a major conduit of sensory input from the face and provides motor innervation to the muscles of mastication. Because of its size and complexity, it is essential to have thorough knowledge of the nerve before diagnoses and treatment of the pathologic processes in the orofacial, temporomandibular, infratemporal, and pterygopalatine areas. The trigeminal nerve is encountered with imaging or surgery of the skull base surgery. Thus, a comprehensive knowledge of the anatomy of the trigeminal nerve is crucial for performing the surgical procedures without significant complication.
Topics: Brain Stem; Cadaver; Dissection; Head; Humans; Mandibular Nerve; Maxillary Nerve; Medical Illustration; Microsurgery; Ophthalmic Nerve; Trigeminal Nerve
PubMed: 24323792
DOI: 10.1002/ca.22330 -
Journal of Clinical Neurophysiology :... Jan 2018The clinical examination of the trigeminal and facial nerves provides significant diagnostic value, especially in the localization of lesions in disorders affecting the... (Review)
Review
The clinical examination of the trigeminal and facial nerves provides significant diagnostic value, especially in the localization of lesions in disorders affecting the central and/or peripheral nervous system. The electrodiagnostic evaluation of these nerves and their pathways adds further accuracy and reliability to the diagnostic investigation and the localization process, especially when different testing methods are combined based on the clinical presentation and the electrophysiological findings. The diagnostic uniqueness of the trigeminal and facial nerves is their connectivity and their coparticipation in reflexes commonly used in clinical practice, namely the blink and corneal reflexes. The other reflexes used in the diagnostic process and lesion localization are very nerve specific and add more diagnostic yield to the workup of certain disorders of the nervous system. This article provides a review of commonly used electrodiagnostic studies and techniques in the evaluation and lesion localization of cranial nerves V and VII.
Topics: Electrodiagnosis; Facial Nerve; Humans; Trigeminal Nerve
PubMed: 29298209
DOI: 10.1097/WNP.0000000000000445 -
The Journal of Craniofacial Surgery Jul 2015The aim of the article is to elucidate the communications between the trigeminal nerve and facial nerve in the face. In a PubMed search, 328 studies were found using the... (Review)
Review
The aim of the article is to elucidate the communications between the trigeminal nerve and facial nerve in the face. In a PubMed search, 328 studies were found using the terms 'trigeminal nerve, facial nerve, and communication.' The abstracts were read and 39 full-text articles were reviewed. Among them, 11 articles were analyzed. In the studies using dissection, the maxillary branch (V2) had the highest frequency (95.0% ± 8.0%) of communication with the facial nerve, followed by the mandibular branch (V3) (76.7% ± 38.5%). The ophthalmic branch (V1) had the lowest frequency of communication (33.8% ± 19.5%). In a Sihler stain, all of the maxillary branches and mandibular branches had communications with the facial nerve and 85.7% (12/14 hemifaces) of the ophthalmic branches had communications. The frequency of communications between the trigeminal nerve and facial nerve were significantly higher (P = 0.00, t-test) in the studies using a Sihler stain (94.7% ± 1.1%) than the studies using dissection (76.9 ± 35.8). The reason for the significantly higher frequency of trigeminal-facial communication in the studies using a Sihler stain is because of the limitation of the Sihler stain itself. This technique cannot differentiate the motor nerves from sensory nerves at the periphery, and a crossover can be misinterpreted as communication near to nerve terminal.
Topics: Facial Nerve; Humans; Mandibular Nerve; Maxillary Nerve; Motor Neurons; Neural Pathways; Ophthalmic Nerve; Sensory Receptor Cells; Trigeminal Nerve
PubMed: 26114519
DOI: 10.1097/SCS.0000000000001810