Multiple cranial neuropathy: Clinical findings in a case series of 142 patients.

INTRODUCTION: Multiple cranial neuropathies (MCN) is an entity frequently seen in clinical practice but there is a lack of studies published about this entity, with most of them based on case reports and small case series. OBJECTIVE: The aim of this study is to describe the clinical involvement of different cranial nerves, the location within the central or peripheral nervous system and the diagnosis in a group of patients with MCN managed in one hospital in Bogotá-Colombia. METHODOLOGY: A case series study was conducted using the electronic clinical records of a teaching hospital in Bogota-Colombia. Clinical data were collected from patients aged ≥18 with a clinical diagnosis of MCN between 2015 and July 2021. RESULTS: The cranial nerves most commonly affected were III and VII, with the most prevalent combinations being III-IV, III-VI, and V-VII. Among etiologies, the most frequently found were autoimmune, vascular and neoplastic and most common locations included peripheral nerves, neuromuscular junction, cavernous sinus and lateral medulla. CONCLUSIONS: The differential diagnosis of MCN is broad, but clinical clues may aid in identifying the underlying etiology. According to our results, MG was the most frequent etiology, so it should be considered in any patient with a clinical diagnosis of MCN associated with fatigability.

Implication of the inferolateral trunk of the cavernous internal CAROTID artery in cranial nerve blood supply: Anatomical study and review of the literature.

The inferolateral trunk (ILT) is one of the two more common branches of the cavernous internal carotid artery (ICA). Its knowledge is important for skull base surgery and endovascular interventional procedures. The ILT is described with superior, anterior and posterior branch, which is the complete form. These branches vascularize the oculomotor, trochlear, trigeminal and abducens nerves into the cavernous sinus and superior orbital fissure (SOF) courses, and through the foramens rotundum and ovale. We performed 21 injected embalmed cadaveric dissections combined with six specimen tomodensitometry. The ILT originates from the horizontal ICA segment and passes above the abducens nerve. Three branches arise from the ILT between the cavernous ICA and the ophthalmic and maxillary nerves initial courses. The main differences with the literature are the number of branches and their cranial nerves' blood supply. The more frequent ILT conformation is the incomplete form with anterior and posterior branch (13/21); the complete form is present in 5/13 sides (38%) and the ILT is in common with the meningohypophyseal trunk in 3/21 (14%) sides. The anterior branch always vascularizes the cranial nerves into the SOF course and most often the maxillary nerve through the foramen rotundum. The posterior branch always vascularizes the mandibular nerve through the foramen ovale course and sometimes the maxillary nerve. This study has demonstrated that there are anastomoses between these branches and arteries arising from the external carotid. This study explains why the sacrifice of a branch of the ILT does not implicate cranial nerve palsy.

The Rhomboid Lip: Anatomy, Pathology, and Clinical Consideration in Neurosurgery.

OBJECTIVE: To describe microsurgical anatomy of the rhomboid lip (RL) and to consider its role by presenting histology and clinical cases. METHODS: We examined 10 (20 sides) formalin-fixed adult human cadaveric heads injected with colored silicone. A total of 20 RLs were examined posteriorly. We examined the expansion of the RL in the cerebellopontine cistern. We assessed the relationship between the RL and choroid plexus and the RL and cranial nerve IX and classified the RL. We also observed these relationships in clinical cases during surgeries and examined histologic assessments of the RL. RESULTS: The RL was divided into 3 types, non-extension type, lateral extension type, and jugular foramen type, according to the relationship between the RL and choroid plexus. There were many variations of the extension of the RL. The jugular foramen type was rare. CONCLUSIONS: Histologically, the RL is the remnant of the fourth ventricle covered with ependymal cells. Knowledge of the detailed anatomy and proper dissection of the RL may help surgeons to obtain good visualization of structures around the foramen of Luschka.

Anatomical map of the cranial vasculature and sensory ganglia.

There is growing evidence of a direct influence of vasculature on the development of neurons in the brain. The development of the cranial vasculature has been well described in zebrafish but its anatomical relationship with the adjacent developing sensory ganglia has not been addressed. Here, by 3D imaging of fluorescently labelled blood vessels and sensory ganglia, we describe for the first time the spatial organization of the cranial vasculature in relation to the cranial ganglia during zebrafish development. We show that from 24 h post-fertilization (hpf) onwards, the statoacoustic ganglion (SAG) develops in direct contact with two main blood vessels, the primordial hindbrain channel and the lateral dorsal aortae (LDA). At 48 hpf, the LDA is displaced medially, losing direct contact with the SAG. The relationship of the other cranial ganglia with the vasculature is evident for the medial lateral line ganglion and for the vagal ganglia that grow along the primary head sinus (PHS). We also observed that the innervation of the anterior macula runs over the PHS vessel. Our spatiotemporal anatomical map of the cranial ganglia and the head vasculature indicates physical interactions between both systems and suggests a possible functional interaction during development.

Macrovascular Decompression of the Brainstem and Cranial Nerves: Evolution of an Anteromedial Vertebrobasilar Artery Transposition Technique.

BACKGROUND: Tortuous and dolichoectatic vertebrobasilar arteries can impinge on the brainstem and cranial nerves to cause compression syndromes. Transposition techniques are often required to decompress the brainstem with dolichoectatic pathology. We describe our evolution of an anteromedial transposition technique and its efficacy in decompressing the brainstem and relieving symptoms. OBJECTIVE: To present the anteromedial vertebrobasilar artery transposition technique for macrovascular decompression of the brainstem and cranial nerves. METHODS: All patients who underwent vertebrobasilar artery transposition were identified from the prospectively maintained database of the Vascular Neurosurgery service, and their medical records were reviewed retrospectively. The extent of arterial displacement was measured pre- and postoperatively on imaging. RESULTS: Vertebrobasilar arterial transposition and macrovascular decompression was performed in 12 patients. Evolution in technique was characterized by gradual preference for the far-lateral approach, use of a sling technique with muslin wrap, and an anteromedial direction of pull on the vertebrobasilar artery with clip-assisted tethering to the clival dura. With this technique, mean lateral displacement decreased from 6.6 mm in the first half of the series to 3.8 mm in the last half of the series, and mean anterior displacement increased from 0.8 to 2.5 mm, with corresponding increases in satisfaction and relief of symptoms. CONCLUSION: Compressive dolichoectatic pathology directed laterally into cranial nerves and posteriorly into the brainstem can be corrected with anteromedial transposition towards the clivus. Our technique accomplishes this anteromedial transposition from an inferolateral surgical approach through the vagoaccessory triangle, with sling fixation to clival dura using aneurysm clips.

Arterial supply of the lower cranial nerves: a comprehensive review.

The lower cranial nerves receive their arterial supply from an intricate network of tributaries derived from the external carotid, internal carotid, and vertebrobasilar territories. A contemporary, comprehensive literature review of the vascular supply of the lower cranial nerves was performed. The vascular supply to the trigeminal, facial, vestibulocochlear, glossopharyngeal, vagus, spinal accessory, and hypoglossal nerves are illustrated with a special emphasis on clinical issues. Frequently the external carotid, internal carotid, and vertebrobasilar territories all contribute to the vascular supply of an individual cranial nerve along its course. Understanding of the vasculature of the lower cranial nerves is of great relevance for skull base surgery.

[Vascular compression syndromes of the cranial nerves]. / Az agyidegek vascularis kompressziós szindrómál.

The blood vessels which are running nearby the cranial nerves and the brainstem can be elongated; curves and loops of the vessels may develop mostly due to the degenerative alterations of ageing and these vessels can compress the surrounding neural elements. The authors report a review of vascular compression syndromes based on the literature and their own experience. The typical clinical symptoms of the syndromes subserving the proper diagnosis, the pathomechanism, the significance of imaging especially the magnetic resonance angiography, the experience with the surgical technique of microvascular decompression which is the only causal treatment of the syndromes are discussed. In cases of non-responsible medical treatment the microvascular decompression should be the eligible treatment in certain syndromes (trigeminal and glossopharyngeal neuralgia, hemifacial spasm) for it is a highly effective and low risk method.

The ascending pharyngeal artery and its relevance for neurosurgical and endovascular procedures.

OBJECTIVE: The ascending pharyngeal artery (APA), a branch of the external carotid artery (ECA), supplies the lower cranial nerves, superior cervical ganglion, and nasopharyngeal structures. The APA can also supply blood to various intracranial lesions. We studied the anatomy of the APA in the context of its neurosurgical and endovascular relevance. METHODS: The cervical origin, branching pattern, and course of the APA were studied in 20 human cadaveric craniocervical sides. The diameter of the APA, the extension of its main trunk, and the distance of its origin from the common carotid artery bifurcation were measured. The relationships between the APA and surrounding structures were also observed. RESULTS: In 80% of the specimens, the APA originated from the ECA. It originated from its medial wall in 56% and from the posterior wall in 44%. The APA originated from the internal carotid artery, common carotid artery bifurcation, occipital artery, and a trunk common to the lingual and facial arteries in 5% each. The APA was usually the third branch of the ECA (40%). The mean distance from the origin of the APA to the common carotid artery bifurcation was 15.3 mm (range, 0-32; standard deviation, +/- 8.3 mm). The APA was frequently the second smallest branch of the ECA (caliber, 1.54 mm; range, 1.1-2.1; standard deviation, +/- 0.25 mm). CONCLUSION: The APA is an important channel for supplying neural structures of the posterior fossa. Knowledge of its anatomy, variants, and anastomotic channels is essential in the treatment of lesions supplied by its branches and to avoid complications related to its inadvertent injury.

The diagnostic dilemma of neuro-imaging in acute isolated sixth nerve palsy.

PURPOSE OF REVIEW: Microvascular ischemia is a frequent cause of acute isolated cranial nerve six (CN VI) palsy. Alternative etiologies of CN VI palsy with grave neurological implications often cannot be excluded without neuroimaging. However, the practice of obtaining neuro-imaging for every patient presenting with an acute, isolated CN VI palsy is a costly diagnostic paradigm. Recent studies have sought to delineate the risk factors for microvascular ischemic ocular motor cranial neuropathies and to investigate the utility of neuroimaging in the initial evaluation of such cases. The aim of this review is to provide an update on the issues and controversies of neuroimaging in the initial evaluation of an acute isolated CN VI palsy. RECENT FINDINGS: Diabetes mellitus, but not hypertension alone, is a risk factor for microvascular ischemic ocular motor cranial neuropathies. Small-scale prospective studies have suggested that immediate neuroimaging should be considered in the initial evaluation of all patients with CN VI palsy, regardless of the presence of microvascular ischemic risk factors. SUMMARY: There remains a lack of large-scale, prospective, age-specific studies to indicate the diagnostic yield of immediate neuroimaging in the setting of acute isolated CN VI palsy. An algorithm is offered for the evaluation of acute isolated CN VI palsy, which allows for initial expectant observation and re-consideration of obtaining neuroimaging upon follow-up if the ophthalmoplegia does not improve, progresses, or becomes nonisolated.

Dangerous extracranial-intracranial anastomoses and supply to the cranial nerves: vessels the neurointerventionalist needs to know.

Transarterial embolization in the external carotid artery (ECA) territory has a major role in the endovascular management of epistaxis, skull base tumors, and dural arteriovenous fistulas. Knowledge of the potential anastomotic routes, identification of the cranial nerve supply from the ECA, and the proper choice of embolic material are crucial to help the interventionalist avoid neurologic complications during the procedure. Three regions along the skull base constitute potential anastomotic routes between the extracranial and intracranial arteries: the orbital, the petrocavernous, and the upper cervical regions. Branches of the internal maxillary artery have anastomoses with the ophthalmic artery and petrocavernous internal carotid artery (ICA), whereas the branches of the ascending pharyngeal artery are connected to the petrocavernous ICA. Branches of both the ascending pharyngeal artery and the occipital artery have anastomoses with the vertebral artery. To avoid cranial nerve palsy, one must have knowledge of the supply to the lower cranial nerves: The petrous branch of the middle meningeal artery and the stylomastoid branch of the posterior auricular artery form the facial arcade as the major supply to the facial nerve, and the neuromeningeal trunk of the ascending pharyngeal artery supplies the lower cranial nerves (CN IX-XII).

[Imaging anatomy of cranial nerves]. / Imagerie anatomique des nerfs crâniens.

Knowledge of the anatomy of the cranial nerves is mandatory for optimal radiological exploration and interpretation of the images in normal and pathological conditions. CT is the method of choice for the study of the skull base and its foramina. MRI explores the cranial nerves and their vascular relationships precisely. Because of their small size, it is essential to obtain images with high spatial resolution. The MRI sequences optimize contrast between nerves and surrounding structures (cerebrospinal fluid, fat, bone structures and vessels). This chapter discusses the radiological anatomy of the cranial nerves.

The antero-medial triangle: the risk for cranial nerves ischemia at the cavernous sinus lateral wall. Anatomic cadaveric study.

OBJECTIVE: Vascular damage in the cavernous sinus can cause ischemic injury to the cranial nerves. An appropriate anatomical knowledge of the blood supply to the cranial nerves can help to reduce the morbidity associated with cavernous sinus surgery. MATERIAL AND METHODS: Three formalin-fixed and six adult cadaveric fresh heads, with common carotid arteries injected, were used for anatomical dissection in this study. A fronto-temporal craniotomy was performed and the cavernous sinus was explored according to the Dolenc technique. With microsurgical dissection and photographic documentation, we demonstrate the anatomy of the superior orbital fissure artery in the antero-medial triangle. RESULTS: The 12 explored cavernous sinuses demonstrated the presence of two principal branches directly from the intracavernous internal carotid artery that supply the cranial nerves: the infero-lateral trunk and the meningohypophyseal trunk. The artery of the Superior Orbital Fissure (SOF), originated more often from the infero-lateral trunk, and vascularized the III, IV, VI, and VI, and ophtalmic division of the trigeminal nerve (TGN VI) at their entry in the fissure. CONCLUSION: In this study we demonstrate that the superior orbital fissure artery is a branch from the infero-lateral trunk which runs immediately under the reticularis layer at the level of the anteromedial triangle in the lateral wall of the cavernous sinus. The blood supply to all cranial nerves in the SOF is at risk to injury when the lateral wall of the cavernous sinus is transgressed at the anteromedial triangle since the SOF-artery runs superficially at this level.

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 from an embryologic and phylogenetic standpoint. Understanding the arterial supply to the cranial nerves and the potential anastomoses is paramount in the endovascular treatment of dural AV shunts and highly vascularized tumors of the skull base to avoid neurologic deficits.

Ets-1 expression is associated with cranial neural crest migration and vasculogenesis in the chick embryo.

The transcription factor Ets-1 is expressed in many different migratory cell types, suggesting that it may play an important role in regulating motility. To determine whether its expression in the neural crest is consistent with such a function, we have performed a detailed analysis of its expression during early chick embryogenesis. Our results show that this transcription factor is up-regulated in the cranial neural folds and dorsal neural tube approximately 4-6 h prior to commencement of neural crest migration. c-Ets-1 continues to be expressed by migrating cranial neural crest cells and subsequently by some neural crest-derived tissues. In addition to neural crest, we find expression of c-Ets-1 in endothelial cells of blood vessels, in somitic and intermediate mesoderm, in limb buds and in the heart.

Internal carotid aneurysms presenting with mass effect symptoms of cranial nerve dysfunction: efficacy and imitations of endosaccular embolization with GDC.

OBJECTIVE: The authors report a retrospective analysis of their experience in the endosaccular embolization of internal carotid aneurysms which caused mass effect symptoms of cranial nerves (CN) and review the efficacy and limitations of this technique. METHODS: Between April 1997 and August 2002, 12 internal carotid aneurysms that caused mass effect symptoms of CN were treated by endosaccular GDC embolization with parent artery preservation. The locations were the cavernous internal carotid artery (CV) in six patients, carotid-ophthalmic artery (CO) in two patients, and posterior communicating artery (PCo) in four patients. The angiographical size of the aneurysms ranged from 6 to 20 mm, with a mean of 13.3 mm. Duration of symptoms ranged from 0.5 to 120 months, with a mean of 13.7 months. All aneurysms were treated by endosaccular guglielmi detachable coil (GDC) embolization with preservation of the internal carotid artery. RESULTS: Five patients (42%) had complete resolution of symptoms, four (33%) had significant improvement of symptoms, and three (25%) were unchanged. Immediate posttreatment angiographic studies revealed neck remnant (NR) in nine patients and dome filling (DF) in three patients. In one patient (case 10), the resolved symptoms became worse 29 months later. Follow-up angiograms were obtained in 10 patients, and recanalization was observed in four of them (40%). Transient thrombotic complication occurred in only one patient. The group with resolution or improvement of symptoms demonstrated a shorter duration of symptoms before GDC treatment (< or = 12 months). CONCLUSION: Even subtotal endosaccular embolization of aneurysms may reduce mass effect symptoms of cranial nerves. However, careful follow-up is needed because subtotal occlusion carries a future risk of growth.

Transvenous embolization of a direct carotid cavernous fistula through the pterygoid plexus.

Closure of a direct carotid cavernous fistula with detachable coils by transpterygoid venous approach to the cavernous sinus is an alternative technique that may be applied in cases in which other techniques offer increased risk or in which other techniques have failed. In this case report, we present the details of the management of a direct carotid cavernous fistula by this method.

Topographic microsurgical anatomy of the paraclinoid carotid artery.

In this publication, the authors describe the microanatomic topography of the entire paraclinoid area with respect to the paraclinoid segment of the internal carotid artery and its surrounding anatomical structures. Special attention was given to the borders of the paraclinoid area, cavernous sinus, arterial vessels, and cranial nerves passing through the region. The paraclinoid region was defined as a pyramid-formed space formed by the dural covering of the anterior clinoid process. The superior border is formed by the continuity of the anterior petroclinoid fold, anteriorly on the superior surface of the anterior clinoid process and medially in the direction of the diaphragma sellae. This dural sheet encircles the internal carotid artery and forms the so-called distal dural ring of the internal carotid artery. The medial border of the paraclinoid region is formed by the body of the sphenoid bone and the adjacent periosteal sheet. The inferior border is formed by a fibrous plate between the middle and anterior clinoid processes. This so-called proximal dural ring separates the venous compartments of the cavernous area from the paraclinoid area. The lateral border is formed by the lateral surface of the anterior clinoid process with its dural covering. The arterial supply of this region is provided by branches of the intracavernous carotid segment and the ophthalmic artery. The important nerves in close vicinity to the paraclinoidal area are the optic and the oculomotor nerves. Understanding and knowledge of the topographic anatomy of the paraclinoid area is essential for microsurgical exposure of this region.