Trochlear nerve palsy MRI

DJO | Digital Journal of Ophthalmology

Trochlear nerve palsy is the most frequent isolated cranial neuropathy that affects ocular motility. 1 The etiologic mechanism of the disease is unclear Classically, in most cases of presumed congenital trochlear nerve palsy, the exact pathophysiology is not well understood. Studies using high definition Magnetic Resonance Imaging (MRI) have been done, and these are suggestive of two different pathogenic mechanisms in patients with congenital palsy of the superior oblique All neurologists (n=3) and 2 out of 7 investigated ophthalmologists recommended performing MRI scanning in every patient who presented with an ocular cranial nerve palsy, while 5 ophthalmologists (5/7) opted to triage patients for risk factors associated with cranial nerve palsies prior to ordering MRI imaging The trochlear nerve is the fourth cranial nerve and is the motor nerve of the superior oblique muscle of the eye . It can be divided into four parts: nucleus and an intraparenchymal portion. cisternal portion. cavernous sinus portion. orbital portion. On this page: Article: Gross anatomy

High-Resolution 3D MR Imaging of the Trochlear Nerve

  1. MRI can be used to identify lesions or inflammation that affects the parenchyma or brainstem. These lesions can include ischemia or a tumor. MRA illustrates blood flow and can aid in identifying an..
  2. Computed tomography or magnetic resonance imaging Usually, 4th cranial nerve palsy is suspected if a person has characteristic limited eye movement. Computed tomography (CT) or magnetic resonance imaging (MRI) of the brain may be done to identify the cause. Treatment of Fourth Cranial Nerve Palsy
  3. Trauma accounts for roughly 44% of acquired trochlear nerve palsies with nearly 25% of cases being bilateral and, thus, it is the most common etiology of an acquired CN IV palsy. Approximately 75% of all CN IV palsies are congenital and in the pediatric population nearly 50% are congenital
  4. MRI brain with and without contrast TFT, fasting glucose, ESR CSF: meningitis Tests for head and neck cancer: transneural spread. Treatment: Treat underlying disease. Causes of trochlear nerve palsy (CN IV): Nuclear & fasciular: Tumours: glioma, medulloblastoma; Part of a Brainstem stroke syndrome; Basilar area: Meningitis: Bacterial.

MRofOculomotorNervePalsy PamelaY.Blake,AlexanderS.Mark,JorgeKattah,andMartinKolsky PURPOSE:To assess the utility of MR in third cranial nerve palsy. METHODS:We reviewed precontrast and postcontrast MR of 50 patients with third cranial nerve palsy Trochlear nerve palsy, also known as 4th nerve palsy, causes a condition called diplopia. Diplopia is more commonly known as double vision, and is caused by the eye's inability to mesh muscle movement to create a single, unified image Cranial nerve palsies are relatively common after trauma, but trochlear nerve palsy is relatively uncommon. Although traumatic trochlear nerve palsy is easy to diagnose clinically because of extraocular movement disturbances, radiologic evaluations of this condition are difficult to perform because of the nerve's small size Trochlear nerve palsy (4th cranial nerve) is one of the most frequent palsies among the other cranial nerve palsy. In clinical practice, it presents with Superior oblique muscle palsy (SOP), which is the common cause of vertical and torsional strabismus. In this review etiology, incidence, diagnostic methods, and treatmen

Congenital Trochlear nerve palsy is a common cause of congenital cranial nerve (CN) palsy. Patients with congenital CN IV palsies may compensate for diplopia with variable head positioning; chin-down head posture is seen in bilateral CN IV palsy and contralateral head tilt is typically seen in unilateral CN IV palsy Wong AM. Understanding skew deviation and a new clinical test to differentiate it from trochlear nerve palsy. J AAPOS. 2010 Feb. 14 (1):61-7. . Dieterich M, Brandt T. Ocular torsion and perceived vertical in oculomotor, trochlear and abducens nerve palsies. Brain. 1993 Oct. 116 ( Pt 5):1095-104. Fourth cranial (trochlear) nerve palsy is often idiopathic. Few causes have been identified. Causes include the following: Rarely, this palsy results from aneurysms, tumors (eg, tentorial meningioma, pinealoma), or multiple sclerosis. Fourth cranial nerve palsy may affect one or both eyes. Because the superior oblique muscle is paretic, the. Magnetic resonance imaging (MRI) revealed a lobulated mass of 1.8×4 cm with gadolinium enhancement in the area of the pineal gland. The lesion was symmetric around the midline and extended into the tectal area (Fig. 1B and C). Craniotomy and removal of the tumor disclosed a pilocytic astrocytoma that probably originated from the pineal gland

The trochlear nerve palsy completely resolved during follow-up. This case shows the usefulness of high-resolution 3D MRI for evaluating trochlear nerve palsy. View full-text. Article A series of high-definition MRI studies by Yang et al have identified two etiologies of congenital trochlear nerve palsies, with the most common being congenital cranial dysinnervation syndrome. This syndrome was present in 73% of congenital trochlear nerve palsy cases and is characterized by absence of the trochlear nerve and secondary atrophy.

Bilateral trochlear nerve palsies may be a sign of the dorsal midbrain syndrome, with lesions affecting both nerves near the anterior medullary velum. Ischemic neuropathy caused by diabetes or other vasculopathies can affect any segment of the trochlear nerve. In the subarachnoid space, isolated fourth nerve palsy may occur I woke up one morning in January with dizziness and double vision, originally diagnosed as trochlear nerve palsy. I was told it is common not to find any specific cause for it. MRI was normal. Now almost 6 months later, the double vision has gotten better but not resolved

Trochlear Nerve Palsy - StatPearls - NCBI Bookshel

RESULTS: 3D CISS MR imaging depicted the proximal cisternal segment of the trochlear nerve in the transverse, sagittal, and coronal planes in 57 (95%), 51 (85%), and 48 (80%) of 60 nerves, respectively. The distance from the midline to the PE was 3-9 mm, and the maximum visualized length of the trochlear nerve was 1-14 mm Trochlear nerve palsy is not always obvious but head tilting to improve the diplopia—usually away from the affected superior oblique muscle—provides a useful clue. Trauma is the most common cause of an isolated trochlear palsy, followed by microvascular ischaemia (usually associated with negative brain imaging) Therefore, MRI may be required to distinguish between the two. Trochlear nerve palsy (CN IV) Trochlear nerve palsy is the most common cause for vertical extraocular muscle weakness and vertical diplopia. However, other causes of an apparent superior oblique palsy such as myasthenia gravis and thyroid eye disease should be excluded before it can. Fourth nerve palsy, also known as superior oblique palsy or trochlear nerve palsy, occurs when the fourth cranial nerve becomes diseased or damaged. The fourth cranial nerve controls the actions of the superior oblique eye muscle. This external muscle runs from the back of the eye socket to the top of the eye, and is responsible for turning the. Palsies of the trochlear (fourth) cranial nerve are one of the most common causes of acquired vertical diplopia ().While a variety of disorders in the subarachnoid space commonly cause trochlear nerve palsy, intraaxial lesions also may affect the trochlear nerve ().In general, intraaxial lesions usually are accompanied by other neurologic signs and symptoms, but they may be isolated ()

However, MRI may be useful to exclude other lesions responsible of atypical Bell's palsy (gradual-onset palsy, failure to improve with time) or recurrent palsy . On MRI, the facial nerve shows increased enhancement on post-contrast sequences that may involve one or more segments, without nodularity (Fig. 26 ) A 62-year-old man reported a 5-day history of binocular vertical diplopia and blurred vision in his left eye, noticing that his left pupil was dilated. He had suffered a flu-like syndrome 2 weeks before. Clinical exam showed a right trochlear nerve palsy and a left mydriatic pupil. MRI, X chest ray, and analytical results were normal All clinical findings were compatible with left isolated trochlear nerve palsy. Brain MRI revealed a T2-weighted hyper intensity within the right dorsal midbrain at the level of colliculus inferior, suggestive of an ischemic event. A schematic drawing representing the stroke location is also shown . Magnetic resonance imaging angiogram was normal years, suggesting the diagnosis of a trochlear nerve schwannoma. Patients with trochlear nerve schwannomas have a good prognosis.1 Serial imaging, observa-tion, and symptomatic treatment with prism spectacles are indicated. Figure MRI brain with and without gadoliniu In this text, the detailed anatomy of the fourth cranial nerve applicable to imaging will be reviewed. RESULTS: Detailed anatomic knowledge of each segment of the trochlear nerve is necessary in patients with trochlear nerve palsy. A systematic approach to identification and assessment of each trochlear nerve segment is essential

The trochlear nerve palsy completely resolved during follow-up. This case shows the usefulness of high-resolution 3D MRI for evaluating trochlear nerve palsy. (Korean J Neurotrauma 2018;14(2):129-133) KEY WORDS: naoml i di nse- ee hr t maI , gn gi ㆍ Magnetic resonance imaging ㆍSubarachnoid hemorrhage, traumatic ㆍ Trochlear nerve diseases Trochlear Nerve Lesions. • The trochlear nerve is uncommonly affected in isolation. • Trochlear palsy is the most common cause of vertical strabismus. • A pure trochlear palsy is characterized by vertical or diagonal diplopia greatest on downward gaze directed to the opposite side. Excyclodeviation (outer rotation of globe) can be seen as. In one study, the yield of MRI in identifying other causes for sixth cranial nerve palsy was 15% (four patients total; two with metastasis, one with a meningioma and one with aneurysm). The details of past medical history were not provided and the median age of the cohort in this study was 43 years, an age in which there is a higher likelihood.

Video: Neurological Imaging in Acquired Cranial Nerve Palsy

Fourth Cranial Nerve (Trochlear Nerve) Palsies Patients with a fourth nerve palsy have a superior oblique weakness. A fourth nerve palsy results in difficulty looking down when the eye is positioned in toward the nose. Patients complain of binocular vertical (or oblique) diplopia, especially when going down the stairs and reading Inclusion criteria were brain magnetic resonance imaging (MRI) with a lesion suggestive of a schwannoma along the course of the fourth nerve. Exclusion criteria were other causes of fourth nerve palsy, such as congenital, traumatic or microvascular; normal (or lack of) initial brain MRI; lack of adequate clinical information; and disappearance. MRI brain in a patient with isolated acute left trochlear nerve palsy. Axial T1 SE (A), axial T2 FSE (B), Axial T2*GRE (C) and Sagittal T2WI(D) showing a hypointense lesion in the right tectal region at the level of the inferior colliculus with intense blooming on gradient imaging without any flow voids Introduction. Malformative vascular diseases may rarely cause paresis of the fourth cranial nerve as an isolated neurological sign. Even large series of patients with trochlear nerve palsy may not include cases of aneurysms or arteriovenous malformations.1-4 Reports of single cases mainly concern carotid-cavernous fistulas5-8 and aneurysms of the intracavernous carotid artery.9 10 On the.

Magnetic resonance imaging (MRI) or computed tomography (CT) of the brain is done to identify the cause. Fourth Cranial Nerve (Trochlear Nerve) Palsy. OTHER TOPICS IN THIS CHAPTER Cranial Nerve Disorders Overview of the Cranial Nerves. Conjugate Gaze Palsies. MRI is recommended in all patients under the age of 50, those that present with non-isolated abducens nerve palsy, have a history of cancer, or have an absence of microvascular risk factors. However, controversy remains regarding the importance of MRI in elderly patients with isolated abducens nerve palsy and vasculopathic risk factors Lets review your que: No, the trochlear nerve is the 4th cranial nerve and is affected by structures in the brain not the neck. It controls the eye muscle outward and downw It controls the eye muscle outward and downw. Bilateral trochlear palsy due to a primary brain tumor. Neuro-Ophthalmology, 2001. Ronald Bartel It is thought that congenital fourth nerve palsies arise either from the absence of the trochlear nerve or from tendon dysfunction of the superior oblique muscle. One radiologic study using thin-section high-resolution MRI showed that, of 97 patients with congenital fourth nerve palsy, 73% had an absent trochlear nerve and atrophy or hypoplasia.

Congenital superior oblique palsy with superior oblique hypoplasia also can be classified as a CCDD by the MRI documentation of congenital aplasia of the trochlear nerve Ophthalmologic evaluations revealed trochlear nerve palsy on theleft side. High-resolution 3D MRI, performed 20 days post-trauma, revealed continuity of the trochlear nerve and its abutted course by the posterior cerebral artery branch at the brain stem. Chemical irritation due to the SAH and the abuttingnerve course were considered causative. Discussion. Various reports have described isolated trochlear nerve palsy, with aetiologies including head injury,1, -, 4 infarction1, 5, -, 7 and intracerebral haematoma.5, 6, 8, -, 13 Review articles of trochlear nerve palsy before the MRI era reported head trauma, stroke, tumor, congenital anomalies and demyelination as aetiologies.14, -, 16 Isolated trochlear nerve palsy associated.

In patient #2, fourth nerve palsy was diagnosed 13 years prior to confirmation of a trochlear schwannoma by high-resolution MRI. In the third patient disturbing diplopia and head tilt were sufficiently corrected by strabismus surgery (combined oblique muscle surgery). The fourth patient had received stereotactic radiotherapy of an 8 mm schwannoma Magnetic resonance imaging (MRI) revealed an abnormal lesion beside the brainstem. On examination, the patient was noted to have left hemiparesis (manual muscle test 4/5). A cranial nerve examination showed right trochlear nerve palsy and hypesthesia in the area of the right third division of the trigeminal nerve The presence or absence of the trochlear nerve was visualized with thin-section high-resolution MRI of the cranial nerves. MAIN OUTCOME MEASURES: Presence of the trochlear nerve and superior oblique (SO) muscle hypoplasia on MRI, age at the onset of symptoms or signs, ocular motility examination results, objective ocular torsion, and surgical.

The manifestations and diagnosis of fourth nerve palsy, also known as superior oblique paralysis and trochlear nerve palsy, are reviewed here. Palsies of the third and sixth cranial nerves are discussed separately. (See Third cranial nerve (oculomotor nerve) palsy in children and Sixth cranial nerve (abducens nerve) palsy.) ANATOM Summary. Cranial nerve palsy is characterized by a decreased or complete loss of function of one or more cranial nerves. Cranial nerve palsies can be congenital or acquired. Multiple cranial neuropathies are commonly seen in lesions caused by tumors, trauma, ischemia, and infections.While a diagnosis can usually be made based on clinical features, further investigation is often warranted to.

Trochlear nerve Radiology Reference Article

Cranial nerve palsies and other focal neurologic defects may also be manifested in patients with tuberculoma. Due to the long path, the 4 th nerve has through cranium, trochlear nerve palsy is commonly seen after head trauma, compressive lesions or microvascular ischemia Park's three-step test (18). This test is classically performed to identify trochlear nerve palsy. a. If the test localizes to any other muscle other than the superior oblique,think of alternatives, i.e skew deviation, Thyroid eye disease, Myasthenia gravis etc . Perform MRI with contrast, as skew deviation can mimic this presentation. b Here we present the case of a 53-year old man with progressive double vision due to isolated left trochlear nerve palsy. Cranial magnetic resonance imaging (MRI) showed a small tumor within the. Abducens Nerve Lesions. • Lesions of the abducens nerve cause impaired ipsilateral lateral gaze. Therefore, patients with unilateral abducens palsy complain of horizontal diplopia, worst in the direction of the paretic LR muscle. • Unlike a peripheral CN VI lesion, a nuclear CN VI lesion impairs ipsilateral gaze of both eyes

What is the role of MRI and MRA in the workup of trochlear

Isolated superior oblique palsy may be caused by a number of different problems, most commonly an isolated trochlear nerve lesion which is the least common of the three cranial nerve lesions causing double vision, accounting for only 15% in the largest series of 4373 acquired cases.1 Approximately one third of cases of isolated trochlear nerve lesions are idiopathic as in our case, one third. 3.2 Palsy of the Trochlear Nerve. The trochlear nerve is the fourth paired cranial nerve. It is the smallest cranial nerve (by number of axons), yet has the longest intracranial course. It has a purely somatic motor function. In this article, the anatomical course, motor functions and clinical relevance of the nerve will be examined Trochlear nerve 1. TROCHLEAR NERVE Dr Kumar Siddharth MBBS, 2nd Year PG MS Ophthalmology SCBMCH, Cuttack 2. INTRODUCTION Purely motor nerve, supplies only superior oblique muscle of the eye The nerve is named after trochlea, the fibrous pulley through which the tendon of the superior oblique muscle passes Only cranial nerve to arise from the dorsal aspect of the brain Trochlear nerve contains.

Magnetic resonance imaging (MRI) revealed a lesion from the orbit to the base of the skull, and the patient was referred to our department. Ophthalmological evaluation showed left visual acuity impairment, left oculomotor nerve palsy, and left trochlear nerve palsy An unusual case of isolated trochlear nerve palsy Mohammed M. Jan, MBChB, FRCP(C). 149 schwannoma or metastases,4,5 pseudotumor cerebri,6 or vascular insult.7 Trochlear nerve palsy is rarely encountered in children and only 5% of patients are truly isolated, namely, without othe Ophthalmoplegic migraine is a rare condition characterized by headache and oculomotor nerve palsy lasting days to weeks. MRI findings include reversible enhancement of the cisternal segment of the oculomotor nerve and focal thickening at the exit of the nerve in the interpeduncular cistern (Figs. 9A, 9B, and 9C) Cranial Nerves Normal MRI Anatomy. 1st CN - Olfactory Nerve. 2nd CN - Optic Nerve. 3rd CN- Occulomotor Nerve, 4th CN - Trochlear Nerve. 5th CN - Trigeminal Nerve. 6th CN - Abducens Nerve, 7 8 th CN Complex - Facial and Vestibulochoclear Nerve. 9th CN - Glassopharyngeal Nerve, 10th CN Vagus Nerve. 11th CN - Spinal Accessory Nerve, 12th CN.

Fourth Cranial Nerve (Trochlear Nerve) Palsy The cause of a fourth cranial nerve palsy, or a trochlear nerve palsy, is not always easy to identify. The majority of cases are due to head trauma and stroke; however there are many other causes. Urgent evaluation should be obtained for any patient experience new double vision Trochleitis is an inflammation of the trochlea and peritrochlear region. This disease may be isolated (occur alone or with migraine) or develop in association with an inflammatory or immunologic condition. Diagnosis is based on clinical findings and confirmed with radiologic images. A typical pain in the superior and inner angle of the orbital region is pathognomonic —Cavernous sinus thrombophlebitis caused by paranasal sinusitis in 62-year-old woman with right ocular pain and diplopia due to oculomotor, trochlear, and abducens nerve palsy. Contrast-enhanced coronal ( B ) and axial ( C ) T1-weighted images show diffuse enhancement of right orbital contents due to orbital cellulitis and ophthalmitis The trochlear nerve is the only nerve with a root entry zone arising from the dorsal (posterior) brainstem. After exiting the pons, the trochlear nerve curves forward over the superior cerebellar peduncle, then runs alongside the oculomotor nerve between the posterior cerebral and superior cerebellar arteries ( , 4 )

Fourth Cranial Nerve (Trochlear Nerve) Palsy - Brain

Welcome to Soton Brain Hub - the brain explained!In this video we quickly summarise trochlear nerve palsy. We keep it nice and simple!If you like what we do,.. MRI is a more sensitive imaging technique than CT scan for the evaluation of a nonaneurysmal cause of third nerve palsy (inflammation, demyelination, ischemic infarction, abscess, or tumor)

oculomotor nerve (43,3%) and trochlear nerve (6,7%)[1]. Oculo-motor nerve palsy tends to be seen inpatient over the 50 years in diabetic neuropathy [11]. Isolated palsy of the nerve is a well-known manifestation of diabetic cranial neuropathy [3]. Our patient presented with combined oculomotor and trochlear nerve palsy which is very uncommon magnetic resonance imaging (MRI) in nine patients with congenital Brown syndrome [2]. In contrast, Kaeser et al. reported an absent trochlear nerve with normal sized SO muscles [3], and Ellis et al., a hypo-plastic SO in congenital Brown syndrome without confirming the status of the trochlear nerve, suggest

Netra Niwas - Neuro ophthalmology Network

Trochlear nerve palsy is an infrequent finding in the case of cranial nerve injuries after minor head trauma. 5, 11, 14) It can result from trauma because of its close proximity to the tentorial incisura and the long course of the nerve in the subarachnoid space. 5, 6, 14) The trochlear nerve palsy results in diplopia, which is secondary to the vertical and horizontal deviation, and occasional. false localising signs; intracranial hypertension; nerve palsy; IIH, intracranial hypertension; MRI, magnetic resonance imaging; The clinical examination of the nervous system is based on the premise of clinicoanatomical correlation, with a particular neurological sign indicating pathology at a specific locus or pathway within the nervous system. 1 Occasionally, however, this semiology.

Cranial Nerve IV (Trochlear Nerve) Pals

Trochlear nerve palsy . I. Describe the approach to establishing the diagnosis A. List the pertinent elements of the history 1. Binocular vertical or oblique diplopia. 2. May describe torsion. 3. May be painful. 4. May be maximal at onset, gradually progressive, or intermittent depending on etiolog Objectives To compare the surgical outcomes of inferior oblique (IO) myectomy in congenital superior oblique palsy (SOP) according to the presence of the trochlear nerve identified with high-resolution MRI. Data Extraction Forty-one congenital SOP patients without a trochlear nerve (absent group) and 23 patients with a trochlear nerve (present group) who underwent IO myectomy as the primary. Cranial nerve palsies and other focal neurologic defects may also be manifested in patients with tuberculoma. Due to the long path, the 4 th nerve has through cranium, trochlear nerve palsy is commonly seen after head trauma, compressive lesions or microvascular ischemia

Trochlear Nerve Palsy (Cranial IV palsy

Trochlear nerve (CN IV) can be damaged in skull base, brainstem and cavernous sinus surgery. CN IV palsy can leads to vertical diplopia with weakness of downward eye movement. The affected eye shifts upward to the normal eye. The leading causes of CN IV palsy are head trauma (53%), followed by surgery (14%) and inflammation (14%) [1] Congenital superior oblique palsy and trochlear nerve absence: a clinical and radiological study. Ophthalmology. 2012;119:170-8. Article PubMed Google Scholar 8. Lee DS, Yang HK, Kim JH, Hwang JM. Morphometry of the trochlear nerve and superior oblique muscle volume in congenital superior oblique palsy

Combined superior rectus hypoplasia and superior oblique» i

Magnetic resonance imaging (MRI) revealed a lesion from the orbit to the base of the skull, and the patient was referred to our department. Ophthalmological evaluation showed left visual acuity impairment, left oculomotor nerve palsy, and left trochlear nerve palsy Slow onset third nerve palsy and a progressive third nerve palsy in a child should prompt magnetic resonance imaging (MRI) of the brain with specific attention to the cavernous sinus. Fourth (trochlear) nerve palsy is the commonest pediatric cranial nerve palsy. Due to a long intracranial course, this nerve is vulnerable to trauma The trochlear nerves as well as normal-sized superior oblique muscles were observed in 24 (100%) of 24 eyes screened as controls. Conclusions: Congenital superior oblique palsy with superior oblique hypoplasia also can be classified as a CCDD by the MRI documentation of congenital aplasia of the trochlear nerve The presence of facial symmetry is usually assessed subjectively, which varies with the examiner. We aimed to objectively assess facial asymmetry in patients with unilateral congenital SOP according to the presence or absence of the trochlear nerve on high-resolution magnetic resonance imaging (MRI). Methods

What Is 4th Nerve Palsy and How Do We Treat It

In one MRI study, 73% of children with a congenital IVth nerve palsy had radiologic absence of the trochlear nerve and a small atrophic superior oblique muscle. Patients with an absent trochlear nerve had higher degrees of head tilt, facial asymmetry, and vertical misalignment 3) Feinberg, A.S., Newman, N.J. Schwannomas in patients with isolated unilateral trochlear nerve palsy. Am J Oph 1999 Feb;127(2):183-8. 4) S. Santoreneos, A. Hanieh and R. Jorgensen, Trochlear nerve schwannomas occurring in patients without neurofibromatosis: case report and review of the literature. Neurosurg 41 (1997), pp. 282-287

Isolated abducens nerve palsy with hyperhomocysteinemiaNeuro-ophthalmology - School of Medicine Blogs - Stanford

Delayed Trochlear Nerve Palsy Following Traumatic

Cranial nerves—oculomotor (III), trochlear (IV), ophthalmic (V1), and maxillary (V2) divisions of trigeminal and the abducens (VI) lie in close association of the cavernous sinus. Abducens nerve (VI) lies close to the intracavernous internal carotid artery, within the substance of the sinus and is hence easily susceptible to vascular insult Trochlear schwannomas may have a variety of presentations ranging from isolated trochlear nerve palsy—as in this case—to hemiparesis, cerebellar signs, or other cranial nerve deficits . Trochlear nerve palsy has only been seen in about half of the surgically confirmed trochlear schwannomas [ 3 , 16 ] 19. Slavin M. Isolated trochlear nerve palsy secondary to cavernous sinus meningioma. Am J Ophthalmol. 1987;104:433-4. 20. Arruga J, de Rivas P, Espinet H, Conesa G. Chronic isolated trochlear nerve palsy produced by intracavernous internal carotid artery aneurysm. J Clin Neuro-ophthalmol. 1991;11:104-8. 21. Rosenberg RN. Comprehensive Neurology

Cranial Nerve 4 Palsy - EyeWik

The trochlear nerve (TN) has the longest intracranial course and the smallest diameter of the 12 cranial nerves. The TN arises from the dorsal midbrain as a pair, inferior to the inferior colliculi, turning around the lateral aspect of the midbrain, passing forward to enter the cavernous sinus, and traversing the superior orbital fissure Trochlear nerve. Trochlear nerve is a fourth cranial nerve (CN IV) that carries motor fibers to innervate the superior oblique muscle, an extra-ocular muscle in the orbit 1), that controls abduction and intorsion of the eye 2).Trochlear nerve damage results diplopia (double vision) with inability to look inferiorly when the eye is adducted (down and in) For example, a right sided midbrain lesion causes damage to the right trochlear nucleus (resulting in a left fourth nerve palsy) and damage to descending sympathetic fibers results in a right Horner's syndrome The cells of the trochlear nerve develop in the dorsal and most inferior aspect of the midbrain.They can be identified in older fetuses (around 20 weeks) as large multipolar neurons.While there is no clear discontinuity in the somatic efferent column to clearly separate the superiorly related oculomotor nerve (CN III) nucleus from CN IV, there is an area of reduced cellular density that marks. Presumed Delayed Onset Trochlear Nerve Palsy after Endovascular Treatment for the Aneurysm in Cavernous Portion of Internal Carotid Artery. Jong Hoon Kim 1, Won Jae Kim 2. 1 Department of Neurosurgery, Yeungnam University College of Medicine, Daegu, Korea

An overview of the third, fourth and sixth cranial nerve