Ocular Motor Nerve Research Articles

Usefulness of intraoperative monitoring of oculomotor and abducens nerves during surgical treatment of the cavernous sinus meningiomas

PurposeWe analyzed the usefulness and prognostic value of intraoperative monitoring for identification of the oculomotor (III) and the abducens (VI) nerve in patients with cavernous sinus meningiomas. Material/methods43 patients diagnosed with cavernous sinus meningiomas were divided according to their topography. Function of the nerves was scored on original clinical and neurophysiological scales. ResultsThe percentage of nerves identified correctly with the monitoring was significantly higher (91% vs. 53% for nerve III and 70% vs. 23% for nerve VI, p<0.001). The fractions of nerves III and VI identified correctly by means of the monitoring were significantly higher in the case of tumors with intra- and extracavernous location (89% vs. 32%, p<0.01) and intracavernous tumors (80% vs. 20%, p<0.05), respectively. The quality of post-resection recording correlated with functional status of both the nerves determined 9 months after the surgery (R=0.51, p<0.001 for nerve III and R=0.57, p<0.01 for nerve VI). Even a trace or pathological response to the post-resection stimulation was associated with improved functional status (90% vs. 50%, p<0.05 for nerve III and 93% vs. 38%, p<0.01 for nerve VI). ConclusionsNeurophysiological monitoring of ocular motor nerves enables their intraoperative identification during resections of the cavernous sinus meningiomas. Intraoperative monitoring of nerve III is particularly important in the case of tumors with extra- and intracavernous location, and the monitoring of nerve VI in the case of intracavernous tumors. The outcome of the post-resection monitoring has prognostic value with regard to the clinical status of the nerves on long-term follow-up.

Do patients with neurologically isolated ocular motor cranial nerve palsies require prompt neuroimaging?

Do patients with neurologically isolated ocular motor cranial nerve palsies require prompt neuroimaging?

Ocular manifestations of head injury and incidence of post-traumatic ocular motor nerve involvement in cases of head injury: a clinical review

As the eyes are in close proximity to the skull, they can get simultaneously affected in head injuries. This close association warrants careful ocular examination in all cases of head injury. This is a prospective non-randomized analytical study to evaluate various ocular manifestations in cases of head injury with special reference to ocular motor nerve involvement, correlation between pupillary changes, and survival. A total of 1,184 patients with head injury were screened for ocular manifestations. This study comprises 594 patients with ocular manifestations of head injury. All the relevant data was compiled and analyzed as per proforma. Ocular manifestations were evaluated in each patient and appropriate investigations were carried out. Patients with ocular morbidity were analyzed for age, sex, mode of injury, Glasgow Coma Score, and associated injuries in addition to ophthalmic and neurosurgical evaluations. Of the 594 patients, 81.6 % were male and 18.4 % were female, with a male-to-female ratio of 4:1. The major cause of head injury was road traffic accidents (70.37 %). The most common age group involved was, 21-40-year-olds (67.40 %). Out of 594 patients, ecchymosis was found in 51.85 %, subconjunctival hemorrhage in 44.44 %, lid edema in 41.48 %, lacerated wound in 22.59 %, pupillary involvement in 21.04 %, ptosis in 6.73 %, cranial nerve palsy in 11.62 %, orbital fractures in 10.44 %, optic nerve trauma in 4.04 %, and exposure keratitis in 4.21 %. Patients with bilaterally dilated or pinpoint fixed pupils had a 10 times higher risk of mortality than patients without pupillary involvement. Third nerve involvement was seen 2.85 times more frequently in frontal and parietal region injuries compared to other sites of injury. The involvement of the sixth nerve occurred 4.6 times more frequently in parietal region injuries compared to other sites of injury.

T2-SPACE MRI for the ocular motor nerves in the brainstem of normal controls

To study the detail functional anatomy of ocular motor nerves in the brainstem by high-resolution magnetic resonance imaging (MRI). Sixty eight normal subjects with high resolution MRI were recruited in our study. The ocular motor nerves at the brainstem were performed using 3-dimensional, T(2)-weighted Turbo-Spin-Echo sequence with high sampling efficiency sequence (3D T(2)-SPACE), Parameters: TR = 1000 ms, TE = 134 ms, averages = 2, thickness = 0.8 mm, FOV = 225 mm×225 mm, matrix = 384×384, total scanning time is 4 min 2 s. Nerves in the brainstem were observed in oblique axial, oblique sagittal and coronal planes acquired with multi-planar reformation (MPR). The diameters of oculomotor nerves (CN3) and abducens (CN6) in the brainstem were measured in 68 normal subjects on MR images by 2 neuro-radiologists. All of 136 CN3 and CN6 of the cisternal segment were well demonstrable in 68 normal subjects (100%). Trochlear nerves (CN4) were depicted 87%. The diameters of CN3 and CN6 in the cistern were 2.2 mm, 1.3 mm, had no linear correlation with age. There were no significant difference between the results of the 2 radiologist (F = 2.557, 1.329, P = 0.085, 0.271). T(2)-SPACE sequence combined with MPR could precisely show the ocular motor nerves, as well as the relationship with adjacent structures in the cistern. The exact data measurement can provide more accurate anatomical basis for some special forms of neuropathic strabismus.

Towards understanding ocular motility: III, IV and VI

The study of the ocular-motor nerves must be exhaustive from their source (nuclei in the brainstem) down to the effector muscles (orbit). Visual disturbances have to be analysed by differentiating between a decrease in visual acuity and ocular-motor disorders. Imaging tests are dominated by MRI, including fine slices and gadolinium injection. A study of the Circle of Willis vessels is often useful, and essential in the case of type III impairment. A further CT scan is essential for analysis of the foramina, base of the skull and orbital walls. Impairment of CN VI requires a CT scan of the apex of petrous. The study of the cavernous sinuses must be in-depth (T2 and T1 after gadolinium and elimination of fats) and always comparative. Impairment of CN III is often complex, difficult to identify precisely (complete or partial, with or without a pupil impairment, associated with other neurological signs) and requires a reasoned study based on anatomical, semiological and pathological knowledge. Other than tumour diseases, it is necessary to consider less well known malformative, ischemic and inflammatory aetiology.

Partial Third Nerve Palsy and Ocular Neuromyotonia From Displacement of Posterior Communicating Artery Detected by High-Resolution MRI

Ocular neuromyotonia is an unusual condition in which sustained, undesired contraction of one or more extraocular muscles occurs after normal muscle activation. Although most commonly reported after paraseller cranial irradiation for tumor, chronic nonaneurysmal vascular compression of the third nerve can produce partial ocular motor nerve paresis and ocular neuromyotonia. A 75-year-old woman presented with intermittent left-gaze-evoked binocular diplopia. She had an incomplete right third nerve palsy but became symptomatically diplopic and esotropic upon sustained left gaze. High-resolution brain magnetic resonance imaging showed displacement of the right posterior communicating artery and contact with the right third nerve. Gaze-evoked diplopia resolved with carbamazepine, but a partial third nerve paresis remained.

Tolosa-Hunt Syndrome: A Case Report and Review of the Literature

Tolosa-Hunt Syndrome is a painful ophthalmoplegia which is characterized by periorbital or hemicranial pain, with ipsilateral ocular motor nerve palsies, oculosympathetic paralysis, sensory loss in the distribution of the ophthalmic and occasionally the maxillary division of the trigeminal nerve. Various combinations of these cranial nerve palsies may occur, localising the pathological process to the region of the cavernous sinus/superior orbital fissure. We report the case of a patient presented with severe pain in the right side of face which was periorbital with ipsilateral 3rd,4th, 6th cranial nerve palsies along with ophthalmic and maxillary division of trigeminal nerve involvement. MRI of orbit showed hypo-intense lesion in right cavernous sinus extending to right superior orbital fissure (suggestive of granulomatous infiltration). After taking oral steroid her pain was relieved quickly and cranial nerve palsies reversed within one week. Azathioprin was added and she was completely cured of within next three months.&#x0D; Bangladesh Journal of Neuroscience 2013; Vol. 29 (2) : 130-133

Painful ophthalmoplegia: The role of imaging and steroid response in the acute and subacute setting

Background and purposeAlthough reports of single cases of painful ophthalmoplegia (PO) are common, studies considering larger case series are lacking. Here, we aimed to determine the relative frequencies of ocular neuropathies, the causes, the usefulness of diagnostic procedures and the role of steroid treatment in PO. MethodsBetween January 2006 and September 2012, 149 patients' charts who presented with diplopia in our emergency department were studied retrospectively. 34 of them met the inclusion criteria that included recent (≤3days) symptom onset and a minimum of diagnostic work. Results32% of single or combined ocular motor nerve palsies were of diabetic microvascular etiology and most of them were IIIrd or VIth nerve neuropathies. The most useful, in terms of sensitivity and specificity of diagnostic test in the acute setting was ESR, whereas MR-angiography and focused cavernous sinus imaging led to diagnosis in the post-acute phase. Pain response to steroids was non-specific, in contrast to palsy improvement after steroid administration which was indicative of Tolosa–Hunt syndrome or temporal arteritis. ConclusionsAlthough acute and subacute PO might be intuitively associated with Tolosa–Hunt syndrome or sinister pathology such as aneurysmal hemorrhage, our data show that these causes are far less common than diabetic microvascular palsies. Brain CT, MR-imaging of brainstem, cerebellum or hemispheres, CSF analysis and pain response to steroids are nonspecific and hence less helpful in order to arrive at a diagnosis. Instead, improved ocular motility after steroid treatment, as well as MR-angiography and cavernous sinus imaging appear more useful for this purpose.

Isolated Third, Fourth, and Sixth Cranial Nerve Palsies from Presumed Microvascular versus Other Causes: A Prospective Study

To estimate the proportion of patients presenting with isolated third, fourth, or sixth cranial nerve palsy of presumed microvascular origin versus other causes. Prospective, multicenter, observational case series. A total of 109 patients aged 50 years or older with acute isolated ocular motor nerve palsy. Magnetic resonance imaging (MRI) of the brain. Causes of acute isolated ocular motor nerve palsy (presumed microvascular or other) as determined with early MRI and clinical assessment. Among 109 patients enrolled in the study, 22 had cranial nerve III palsy, 25 had cranial nerve IV palsy, and 62 had cranial nerve VI palsy. A cause other than presumed microvascular ischemia was identified in 18 patients (16.5%; 95% confidence interval, 10.7-24.6). The presence of 1 or more vasculopathic risk factors (diabetes, hypertension, hypercholesterolemia, coronary artery disease, myocardial infarction, stroke, and smoking) was significantly associated with a presumed microvascular cause (P = 0.003, Fisher exact test). Vasculopathic risk factors were also present in 61% of patients (11/18) with other causes. In the group of patients who had vasculopathic risk factors only, with no other significant medical condition, 10% of patients (8/80) were found to have other causes, including midbrain infarction, neoplasms, inflammation, pituitary apoplexy, and giant cell arteritis (GCA). By excluding patients with third cranial nerve palsies and those with GCA, the incidence of other causes for isolated fourth and sixth cranial nerve palsies was 4.7% (3/64). In our series of patients with acute isolated ocular motor nerve palsies, a substantial proportion of patients had other causes, including neoplasm, GCA, and brain stem infarction. Brain MRI and laboratory workup have a role in the initial evaluation of older patients with isolated acute ocular motor nerve palsies regardless of whether vascular risk factors are present.

Ocular neuromyotonia: differential diagnosis and treatment

Ocular neuromyotonia (ONM) is a rare but distinctive clinical entity characterized by involuntary episodic contraction of one or more muscles supplied by the ocular motor nerves. A retrospective review was conducted on all patients with ONM seen by the neuroophthalmology service in the past 20 years. Ten patients were identified with ONM; six affecting vertical muscles (superior oblique; inferior rectus; superior rectus) and four affecting lateral rectus muscles. Case 1 has been reported previously. Most episodes occurred every 10–40 min, lasted a few seconds to several minutes, and were repeated throughout the day. Only two patients had previously undergone cranial radiation. Two had thyroid eye disease. One patient presented with superior oblique myokymia and subsequently developed ONM. Membrane stabilizing medications were prescribed in 7 of the 10 patients with varied success. ONM episodes ceased after extraocular muscle surgery in one patient with thyroid eye disease.

English

Tolosa-Hunt syndrome (THS) is a painful ophthalmoplegia caused by nonspecific inflammation of the cavernous sinus or superior orbital fissure. The syndrome consists of periorbital or hemicranial pain, combined with ipsilateral ocular motor nerve palsies, oculosympathetic paralysis, and sensory loss in the distribution of the ophthalmic and occasionally the maxillary division of the trigeminal nerve. Although they have relapsing and remitting course, they respond promptly to systemic corticosteroid therapy. The diagnostic eponym Tolosa-Hunt syndrome has been applied to these patients and it is this entity which forms the basis of this review. CASE REPORT: A 42 year old man presented with painful diminution of vision since one month and diplopia in the left eye since 7 days. Tingling sensation was noted over left half of upper face. On clinical examination –V/A was 6/12 (B/E) improving to 6/6 with pinhole, IOP and fundus was normal both eyes, extra ocular movement was completely restricted in left eye with painful movements. Left III, IV and VI Cranial nerve palsies were noted with decreased sensation over the area supplied by V Cranial Nerve. The patient was sent for an MR examination. MR imaging was performed on a 1.5 Tesla MR scanner (GE). 10ml Gadolinium was injected in the left antecubital vein to obtain post contrast T1WI.Study revealed moderately enhancing soft tissue in the region of left cavernous sinus and orbital apex. It was isointense to muscle on T1WI and hypo intense to fat on T2WI. MANAGEMENT: On the basis of history and imaging findings, a diagnosis of THS was made and the patient was started on corticosteroid therapy: Injection Methyl-Prednisolone (1gm.I.V for 3 days).Dramatic improvement in diplopia and pain was noted within 48 hours of starting IV steroid therapy. Oral Prednisolone 40mg daily was started after 3 days and continued for 6 weeks. At the end of therapy the patient's ophthalmoplegia also recovered. DISCUSSION: Tolosa–Hunt syndrome (THS) is a rare disorder characterized by severe and unilateral headaches with extra ocular palsies, usually involving the third, fourth, fifth, and sixth cranial nerves, and pain around the sides and back of the eye, along with weakness and paralysis (ophthalmoplegia) of certain eye muscles1. The syndrome of painful ophthalmoplegia consists of periorbital or hemicranial pain, combined with ipsilateral ocular motor nerve palsies, oculosympathetic paralysis, and sensory loss in the distribution of the ophthalmic and occasionally the maxillary division of the

Treatment of tolosa-hunt syndrome with acupuncture: A case report

Tolosa-Hunt syndrome is a rare medical condition with special clinical manifestations, characterized by sharp severe headache as the initial symptom. The pain is usually located around the orbit or deep inside, ocular motor nerve palsy following or together with the pain[1]. We treated a case of Tolosa-Hunt syndrome with acupuncture-moxibustion treatment, and now report it as follows.

Surgical outcomes in adult sixth nerve palsy

Sixth nerve palsy (6NP) is the most common adult ocular motor nerve palsy. Our goal was to identify factors associated with surgical outcomes in 6NP. Medical records of all adult patients from 1988-2012 with 6NP who underwent strabismus surgery or botulinum toxin injections were retrospectively reviewed. Success was defined as absence of diplopia without prisms, vertical deviation ≤2Δ, and horizontal deviation ≤10Δ. 83 patients from four surgeons were included [50 (60%) women; mean age 52 (range, 20-86)]. 66 (80%) had unilateral sixth nerve palsies. Palsies were complete in 34 (41%). 21 (25%) had >1 surgery. Underlying etiology was idiopathic/microvascular in 23 (28%), traumatic in 23 (28%), neoplastic in 19 (23%), and miscellaneous causes in 18 (22%). Success frequency was similar across etiologies. 16/42 patients (38%) with trauma or neoplasm required repeat surgery vs 5/41 (12%) with other etiologies (P < 0.05). Success was more frequent with Hummelsheim-type procedures than vertical rectus transposition (VRT) among patients with complete palsies (7/9 = 78% vs 8/23 = 35%; P < 0.05). Success was more frequent among all surgically-treated 6NP patients who had adjustable vs nonadjustable sutures (21/29 = 73% vs 22/44 = 52%; P = 0.06). Etiology of 6NP does not appear to affect surgical success in adults, but patients with traumatic and neoplastic causes were more likely to require repeat procedures. Despite a small number of patients, success was more frequent using the Hummelshiem-type procedure and with adjustable sutures. Surgical success in adults does not correlate with the etiology of the sixth nerve palsy, but may vary based on the type of procedures in this patient population.

Cranial nerves 3,4 and 6: from brainstem to orbit

AbstractPurpose To review the pertinent anatomy of the ocular motor cranial nerves in correlation with their clinical presentationMethods didactic lecture and cassResults The nucleus of the oculomotor nerve (CN3) is composed of several subnuclei. The central caudal subnucleus innervates the levator palpebrae bilaterally. Fibers from the superior rectus subnucleus decussate and innervate the SR muscle of the contralateral eye. Axonal fascicles from each subnucleus remain topographically arranged as they traverse the midbrain. Autonomic fibers (pupil and accommodation) orient dorsomedially in the peripheral nerve as it exits the peduncles of the ventral midbrain. The clinical presentation of a nuclear, fascicular and peripheral lesion of CN3 are distinctive and localizing. The trochlear nerve (CN4) is the smallest cranial nerve yet has the longest pathway. It is susceptible during closed head injury. The abducens nerve (CN6) exits the ventral pons and ascends the clivus to reach the cavernous sinus. It is prone to injury with changes in intracranial pressure. Lesions of the clivus can also cause bilateral abducens palsy.Conclusion Understanding the anatomic pathway of the ocular motor nerves can help focus the etiology and location of the lesion. Commercial interest

MR Imaging of Congenital or Developmental Neuropathic Strabismus: Common and Uncommon Findings

High-resolution MR imaging enables direct imaging of the ocular motor nerves. The aim of this study was to assess the various causes of congenital or developmental neuropathic strabismus by using high-resolution MR imaging. High-resolution MR imaging was performed to evaluate the ocular motor nerves (CNIII, CNIV, CNVI) in 247 consecutive patients with suspected congenital or developmental neuropathic strabismus. These MR images, along with those obtained from conventional MR imaging of the brain and the orbit, were evaluated. MR imaging abnormalities were found in 112 patients: ocular motor nerve abnormalities in 98 patients (88%), orbital abnormalities in 9 patients (8%), and brain abnormalities in 5 patients (4%). Ocular motor nerve abnormalities were CNIV aplasia (63%), CNVI aplasia or hypoplasia (21%), CNIII aplasia or hypoplasia (3%), and combined CNIII aplasia and CNVI hypoplasia (1%). Orbital abnormalities were EOM hypoplasia (7%), EOM hypertrophy (1%), and fibrotic mass (1%). Brain abnormalities were periventricular leukomalacia (4%) and periventricular heterotopia (1%). Various MR imaging abnormalities were associated with congenital and developmental neuropathic strabismus. The most common abnormality was CNIV aplasia.

Isolated Oculomotor Nerve Palsy Caused by Cavernous Sinus Dural Arteriovenous Fistula: Case Report

Isolated oculomotor palsy is a rare symptom seen in patients with many, different neurological disorders (1, 2). It is often the first or even the sole manifestation of a pathology that potentially affects the nervous system. When older patients are presented with isolated ocular motor nerve palsy, without congestive ocular features, this condition is easily misdiagnosed as idiopathic, ischemic mononeuropathy or aneurysm. While isolated ocular motor nerve palsy, presenting as the only manifestation of cavernous dural arteriovenous fistula (DAVF), has occasionally been reported (3-5), we report a case of cavernous DAVF presenting with unusual, isolated oculomotor nerve palsy and treated by transvenous coil embolization.

Oculomotor Nerve Palsy Caused by Posterior Communicating Artery Aneurysm: Evaluation of Symptoms after Endovascular Treatment

We report the outcome of endovascular treatment in a series of patients presenting with posterior communicating artery aneurysm causing ocular motor nerve palsy. A retrospective study was made of ten patients who were treated by coil embolization of posterior communicating artery aneurysm caused by oculomotor nerve palsy. The assessed parameters were as follows: patient's age, presence of subarachnoid hemorrhage, aneurysm size, preoperative severity of symptoms, and timing of treatment after onset of symptoms. Improvement of oculomotor nerve palsy after treatment was noted in eight patients (80.0%). Complete recovery was noted in seven patients (70.0%), partial recovery in one patient (10.0%), and no recovery in two patients (20%). Clinical presentations with early management (≤2 days) were significant in influencing recovery. Complete recovery from ocular motor nerve palsy was significantly higher in patients with initial incomplete palsy compared with initial complete palsy patients (6/6 versus 1/4). Early treatment and initial partial palsy are relevant to improving prognoses. Endovascular treatment is favored method for treating oculomotor palsy.

Vertical retraction syndrome caused by anomalous orbital structures

To described the clinical feature and MRI imaging of six children with vertical retraction syndrome. Six children with unilateral vertical retraction syndrome between 15 months and 8 years of age, mean age was (5.01 ± 1.27) years old. Strabismus examination included diopter, prism diopters, eye movement examination, binocular vision and fundus examination. Imaging of the ocular motor nerves at the brainstem was performed in 0.8 mm thickness image planes using 3D-FIESTA sequence, the orbits were imaged with FSE T1, T2WI using surface coils, and within 2.0 mm thick planes. Four children showed hypertropia, characterized by limited depression, a light retraction of the globe during downward gaze and eyelid lag. The MRI imaging showed anomalous orbital structure in the superonasal quadrant that between medial rectus and superior rectus or adjacent to the superior rectus. Two children showed intermittent exotropia, characterized by limited elevation, retraction of the globe and narrowing of the palpebral fissure during upward gaze. The MRI imaging showed anomalous orbital structure was present in the inferotemporal quadrant, one originate in inferior rectus and another close to the lateral rectus. Anomalous orbital structures are a main cause of vertical retraction syndrome. The presence of specific unusual eye movement and MRI imaging may assist in diagnosis. When the eyelid lag was found since the early age, anomalous orbital structures were implied.

PITUITARY MACROADENOMAS

Objectives: To describe the demographic profile, patterns of visual disturbance and imaging studies of patients with Macroadenoma. Design: Retrospectively. Reviewed the clinical charts and neuroradiologic imaging of 125 patients who were diagnosed as cases of Macroadenoma. Duration: 2000 to 2009. Subjects and Methods: 100 patients were selected who had visual disturbances along with Macroadenomas. Age, sex, visual symptoms and other associated systemic problems of these patients were reviewed. The Neuroimaging data (Magnetic Resonance Imaging) was correlated with the clinical picture. The data was analysed using Statistical package for social sciences (SPSS). The Descriptive Statistics were calculated for age and MR findings. Results: The age ranged from 9 to 85 years (mean 42.92). Male to female ratio was 1.4: 1. 90% patients had visual disturbances including visual field defects and 10% had ocular motor nerve palsies. Tumour extension on MR studies showed optic chiasma compression in 69% patients, cavernous sinus invasion in 57% and Sphenoidal sinus invasion in 14%. Haemorrhagic foci were seen in 8% and intra tumour necrosis was found in 9% patients. Conclusions: The most common path for the extension of pituitary macroadenomas is towards the optic chiasma. Hence majority of these patients present with visual disturbances. MRI is an excellent aid to see the extent and invasion of Macroadenomas to the surrounding structures.

Imaging the ocular motor nerves

The ocular motor nerves (OMNs) comprise the oculomotor, trochlear and the abducens nerves. According to their course, they are divided into four or five anatomic segments: intra-axial, cisternal, cavernous and intra-orbital and, for the abducens nerve, an additional interdural segment. Magnetic resonance imaging is the imaging method of choice in the evaluation of the normal and pathologic ocular motor nerves. CT still plays a limited but important role in the evaluation of the intraosseous portions at the skull base and bony foramina. We describe for each segment of these cranial nerves, the normal anatomy, the most appropriate image sequences and planes, their imaging appearance and pathologic conditions. Magnetic resonance imaging with high magnetic fields is a developing and promising technique. We describe our initial experience with a Phillips 7.0 T MRI scanner in the evaluation of the brainstem segments of the OMNs. As imaging becomes more refined, an understanding of the detailed anatomy is increasingly necessary, as the demand on radiology to diagnose smaller lesions also increases.