Vestibular and oculomotor function in patients with vestibular migraine.

AIM: The purpose of this study was to assess the vestibular and oculomotor function in patients with vestibular migraine (VM). And we also investigate the relationship between testing results and effectiveness of preventive medications in VM. MATERIAL AND METHOD: 41 patients with VM were recruited in this study and examined with cervical and ocular vestibular evoked myogenic potential(cVEMP, oVEMP), video head impulse test(vHIT), caloric test and videonystagmography. All patients were treated with preventive medications. We calculated symptomatic improvement and record episodes frequency in patients with VM. Six months later, the effectiveness of preventive medications were evaluated and the relationship between vestibular testing and effectiveness of preventive medications were analyzed further. RESULTS: In vestibular function testing, 73% of patients with VM showed abnormal results. Abnormal cVEMP, oVEMP, vHIT, and caloric test were found in 20%, 44%, 32% and 56% respectively. The abnormal rate of oVEMP was significantly higher than that of cVEMP(p < 0.05). And the proportion of abnormal caloric test was obviously higher than that of vHIT (p < 0.05). In oculomotor function testing, 42% of the patients with VM showed pathological results which was significantly lower than that of vestibular function testing(p < 0.05). After 6 months follow-up, the proportion of prophylactic medication effectiveness was significantly higher in normal vestibular function testing group compared with the abnormal group (p < 0.05). CONCLUSION: Abnormal vestibular and oculomotor functions are commonly observed in patients with VM. And these patients with abnormal vestibular function possess a weak effectiveness of preventive medications.

Isolated Third Cranial Nerve Palsy in Pituitary Apoplexy: Case Report and Systematic Review.

OBJECTIVES: To report a case of isolated third nerve palsy from pituitary apoplexy and perform a systematic literature review. MATERIALS AND METHODS: MEDLINE/EMBASE databases were searched up to September 2020. INCLUSION CRITERIA: Age≥18, isolated third nerve palsy from pituitary apoplexy. EXCLUSION CRITERIA: Age<18, presence of other neurological findings, no hemorrhage or infarction of pituitary. RESULTS: Case report: A 76-year-old woman presented with headache and right-sided ptosis. Right-eye exam revealed complete ptosis, absent pupillary constriction and accommodation, depressed and abducted eye on primary gaze, and -1 impaired depression, adduction, elevation, without other neurological findings. Brain MRI was suggestive of pituitary apoplexy. Pathology after transsphenoidal resection revealed an infarcted pituitary adenoma. Third nerve palsy resolved completely in 21 days. Systematic review: Twenty-three studies reporting 35 patients were selected from 182 abstracts. Twenty-nine (83%) had complete isolated third nerve palsy. Headache was reported in 31 (97%). Thirty-one had hemorrhage and 1 had infarction of pituitary. Cavernous sinus invasion occurred in 14 (50%). Twenty-eight were managed surgically (80%) and 7 medically (20%). Nerve palsy resolved completely in 27 (82%) and partially in 4 (11%). CONCLUSIONS: Pituitary apoplexy is an important differential diagnosis in patients with isolated third nerve palsy. Isolated third nerve palsy in apoplexy appears to have favorable prognosis.

Plus-minus lid syndrome with ataxia and severe apathy-A rare manifestation of midbrain infarct.

Plus-minus lid syndrome is a rare manifestation of midbrain infarct, characterized by ptosis of one eye and lid retraction in the other eye. It has also been described in ocular myasthenia gravis, orbital myositis, or after lesions of the oculomotor nerve. Our patient was a 55-year-old man with hypertension and atrial fibrillation, who presented to us with acute onset left-sided ptosis and right-sided eyelid retraction. He was apathic and had right-sided ataxia. His MRI of the brain showed acute infarct involving the paramedian midbrain. To our knowledge, severe apathy and resultant executive function disorder have not been described previously in a patient having plus-minus lid syndrome with ataxia.

Assessment of Infraorbital Hypesthesia Following Orbital Floor and Zygomaticomaxillary Complex Fractures Using a Novel Sensory Grading System.

PURPOSE: Introduction of a novel sensory grading system to assess the incidence and long-term recovery of infraorbital hypesthesia following orbital floor and inferior orbital rim fractures. METHODS: Patients who presented for evaluation of orbital floor and/or zygomaticomaxillary complex (ZMC) fractures between January 2015 and April 2016 were analyzed. Two-point subjective infraorbital sensory grading in 5 discrete anatomic areas was performed. Fractures were repaired based on traditional criteria; hypesthesia was not an indication for surgery. The sensory grading system was repeated a mean 21.7 months (range 18-28) after initial fracture. RESULTS: Sixty-two patients (mean 41.8 years) participated in the initial symptom grading, and 42 patients (67.7%) completed the 2-year follow-up. Overall, 20 of 42 patients (47.6%) had some infraorbital hypesthesia. There were fewer with isolated orbital floor fractures versus ZMC fractures (31.8% vs. 68.4%; p = 0.019). Two years postinjury, 9.1% and 40.0% with isolated floor and ZMC fractures, respectively, had persistent sensory disturbance (p = 0.0188). Of patients with sensory disturbance on presentation, 71.4% with isolated floor fractures and 38.5% with ZMC fractures experienced complete sensory recovery (p = 0.1596). Patients with isolated floor fractures had improved recovery after surgery (100% vs. 33.3% recovery; p = 0.0410). Patients with ZMC fractures showed no difference in sensory prognosis between those repaired and observed. CONCLUSIONS: In this pilot study, isolated orbital floor fractures carried a good infraorbital sensory prognosis, further improved by surgical repair. Zygomaticomaxillary complex fractures portended a worse long-term sensory outcome, unaffected by management strategy. This study validates the novel sensory grading system in post-fracture analysis.

Congenital Third Nerve Palsy Associated With Midbrain Hypoplasia Due to Bilateral Segmental Internal Carotid Artery Agenesis.

A 15-year-old girl, diagnosed with a partial right third nerve palsy, was found to have bilateral internal carotid artery agenesis. Neuroimaging with 3D-constructive interference in steady state scanning identified the possible etiology of the third nerve palsy as midbrain hypoplasia.

Neural mechanisms of oculomotor abnormalities in the infantile strabismus syndrome.

Infantile strabismus is characterized by numerous visual and oculomotor abnormalities. Recently nonhuman primate models of infantile strabismus have been established, with characteristics that closely match those observed in human patients. This has made it possible to study the neural basis for visual and oculomotor symptoms in infantile strabismus. In this review, we consider the available evidence for neural abnormalities in structures related to oculomotor pathways ranging from visual cortex to oculomotor nuclei. These studies provide compelling evidence that a disturbance of binocular vision during a sensitive period early in life, whatever the cause, results in a cascade of abnormalities through numerous brain areas involved in visual functions and eye movements.

Homeostatic dysregulation in membrane properties of masticatory motoneurons compared with oculomotor neurons in a mouse model for amyotrophic lateral sclerosis.

Amyotrophic lateral sclerosis (ALS) is a progressive neurodegenerative motoneuron disease with presently no cure. Motoneuron (MN) hyperexcitability is commonly observed in ALS and is suggested to be a precursor for excitotoxic cell death. However, it is unknown whether hyperexcitability also occurs in MNs that are resistant to degeneration. Second, it is unclear whether all the MNs within homogeneous motor pools would present similar susceptibility to excitability changes since high-threshold MNs innervating fast fatigable muscle fibers selectively degenerate compared with low-threshold MNs innervating fatigue resistant slow muscle fibers. Therefore, we concurrently examined the excitability of ALS-vulnerable trigeminal motoneurons (TMNs) controlling jaw musculature and ALS-resistant oculomotor neurons (OMNs) controlling eye musculature in a well studied SOD1(G93A) ALS mouse model using in vitro patch-clamp electrophysiology at presymptomatic ages P8-P12. Our results show that hyperexcitability is not a global change among all the MNs, although mutant SOD1 is ubiquitously expressed. Instead, complex changes occur in ALS-vulnerable TMNs based on motor unit type and discharge characteristics. Firing threshold decreases among high-threshold TMNs and increases in a subpopulation of low-threshold TMNs. The latter group was identified based on their linear frequency-current responses to triangular ramp current injections. Such complex changes in MN recruitment were absent in ALS-resistant OMNs. We simulated the observed complex changes in TMN excitability using a computer-based jaw closer motor pool model. Model results suggest that hypoexcitability may indeed represent emerging disease symptomology that causes resistance in muscle force initiation. Identifying the cellular and molecular properties of these hypoexcitable cells may guide effective therapeutic strategies in ALS.

Clinical Study of Eleven Patients with Midbrain Infarction-Induced Oculomotor Nerve Palsy.

BACKGROUND: Midbrain lesion-induced oculomotor nerve palsy can be divided into the nuclear and infranuclear types. In the infranuclear type, the degree of each subtype of ocular muscle palsy usually varies. METHODS: The neuroradiological findings of 11 patients with midbrain infarction-induced oculomotor nerve palsy were analyzed. Their infarcts were grouped into rostral and caudal lesions. Each group was then divided into lesions that occurred in the paramedian and lateral regions before being subdivided further into lesions that occurred in the tegmental, central, and ventral areas. RESULTS: Unilateral and bilateral infarcts were seen in 9 and 2 patients, respectively. The ventrocentral area of the rostral paramedian region was the most commonly affected part. External ocular muscle palsy was observed in all 11 patients. Ten patients had infranuclear oculomotor nerve palsy. Of these 10 patients, 9 had adduction palsy. Internal ocular muscle palsy was detected in 4 patients. The patient with nuclear type had bilateral ptosis and bilateral elevation palsy and did not exhibit Bell's phenomenon; however, her lesion was unilateral. Vertical gaze palsy was detected in 3 patients who continued to exhibit Bell's phenomenon. CONCLUSIONS: In the 3 cases in which patients with vertical gaze palsy continued to exhibit Bell's phenomenon, it was considered that the palsy was caused by impairment of the rostral interstitial nucleus of the medial longitudinal fasciculus. Our study suggested that the intra-axial fascicular fibers innervating the medial rectus muscle are particularly susceptible to infarction, possibly because they are the most centrally located in the intra-axial oculomotor fascicular fibers.

[On the Relationship between EMDR and Eye Movements - An Analysis of the Current State of Neurobiological Research]. / Zur Beziehung von EMDR und Augenbewegungen - Eine Analyse der aktuellen neurobiologischen Studienlage.

EMDR is an effective treatment for people diagnosed with posttraumatic stress disorder. The traditional technique of EMDR combines the activation of distressing reminders with guided rhythmic eye movements. The present article reviews the current state of research on the neurobiological correlates of the eye movements occurring during EMDR. The distinction between saccades and smooth pursuit eye movements allows for detailed analyses of ocular motor connections with cerebral networks of attention, memory and emotion. Possible consequences for research and clinical practice with EMDR are discussed.

Congenital Oculomotor Nerve Paresis With Isolated Cyclic Pupillary Spasms.

Cyclic oculomotor nerve paresis is a rare and usually congenital disorder. It is characterized by unilateral third nerve paresis with periodic spasms causing eyelid elevation, miosis, and contraction of 1 or more of the extraocular muscles innervated by the third nerve. We report a 20-month-old girl who presented initially with a congenital partial right third nerve paresis without ptosis. She subsequently developed isolated cyclic spasms of the pupil followed several months later by permanent partial ptosis.

MRI findings in Duane's ocular retraction syndrome.

AIM: To investigate the innervation pattern of extra-ocular muscles in patients with clinically diagnosed Duane's ocular retraction syndrome (DRS) using magnetic resonance imaging (MRI). MATERIALS AND METHODS: The study population consisted of 11 patients. Six patients had type I DRS (eight eyes), four patients had type II DRS (five eyes) and one patient had inverse DRS. Images were acquired using a Siemens 3 T MRI system. The type of DRS, corresponding innervation findings, and condition of the affected muscles were evaluated by two experienced neuroradiologists in consensus. RESULTS: All patients with clinically diagnosed DRS type I showed absence of the abducens nerve (CN6), hypoplasia of the superior oblique muscle (SOM), and aberrant innervation of lateral rectus muscle (LRM) by an extra branch of oculomotor nerve (CN3). All patients with type II DRS show dual-innervation of the LRM (by CN6 and an aberrant CN3 branch) and hypoplasia of SOM. The single patient with inverse DRS showed hypoplasia of CN3, the medial rectus muscle (MRM), the inferior rectus muscle (IRM), and the inferior oblique muscle (IOM). CONCLUSION: Each type of DRS has characteristic MRI appearances. Therefore, MRI is a useful diagnostic tool for the confirmation and classification of suspected cases of DRS.

Congenital trochlear-oculomotor synkinesis.

Synkinesis of the extraocular muscles forms a subset of congenital ocular motility abnormalities termed congenital cranial dysinnervation disorders. Synkinesis most frequently involves the abducens or oculomotor nerves and rarely the trochlear nerve. Only 3 such patients have been described in the literature. We report an isolated case of trochlear-oculomotor synkinesis in a healthy 6-year-old boy and discuss the proposed pathophysiology of this disorder.

Screening for lifetime concussion in athletes: importance of oculomotor measures.

HYPOTHESIS/OBJECTIVE: The purpose of the present study was to determine the utility of oculomotor-based evaluation protocols in screening for lifetime concussion incidence in elite hockey players. METHODS: Forty-two Division I collegiate male and female hockey players were evaluated using the guidelines of an overall oculomotor-based diagnostic clinical test protocol for the mTBI population. The sensitivity of the collected measures to lifetime concussion was then compared with the corresponding sensitivity of measures of neuropsychological functioning (ImPACT) often used with athletes for acute concussion diagnosis. RESULTS: This model showed that a hockey player with a Near Point of Fixation Disparity (NPFD) equal to or greater than 15 cm, Visagraph comprehension rate less than 85% and the total score on part A of an ADHD questionnaire equal to or greater than 11 was on average 10.72-times more likely to have previously suffered a concussion than an athlete with lower values on the NPFD and ADHD questionnaire and a higher comprehension rate on the Visagraph. None of the IMPACT baseline assessment measures were significantly predictive of the individual's concussion history. CONCLUSION: The study provides a relatively sensitive screening tool to assess the probability of previous concussion(s) in an athlete. This model may allow athletic personnel to address in a timely manner the risks associated with repeat concussions and to develop individualized concussion management protocols.

[Characteristics of pupil function in patients with dissociated vertical divergence]. / Bestehen Besonderheiten der Pupillomotorik bei dissoziiertem Höhenschielen?

Dissociated vertical divergence (DVD) is frequently associated with the infantile strabismus syndrome. There are different theories on the pathomechanism of this disorder, but none of them is generally accepted. Some authors believe that the slow upward movement of the covered eye is due to a different illumination of both retinae and consequently an unequal activity of the oculomotor nerve's nuclei. In one hypothesis a predominance of crossing pupillary tract fibres from the pretectal area to motor and parasympathetic nuclei of the oculomotor nerve was supposed. The consequence of this abnormal pathway in the midbrain would be a pronounced contraction anisocoria in patients with DVD. In contraction anisocoria the directly illuminated pupil contracts more strongly than the contralateral pupil without any efferent defect. In a small study we compared direct and indirect pupillary light reflexes in 11 DVD patients and 10 normal subjects. We found no significant differences of contraction anisocoria between the two groups. The results do not support the hypothesis of a different pupillary tract pathway in the midbrain of patients with DVD.

The somatosensory blink reflex in upper and lower brainstem lesions.

The brainstem pathways that mediate the somatosensory blink reflex (SBR) are not completely understood. We hypothesized that the circuits of the SBR might be affected separately from those of the trigeminal blink reflex (TBR). We examined 7 patients with mesencephalic lesions and 8 patients with medullary lesions. The SBR was elicited by median nerve stimulation. The TBR was elicited by supraorbital nerve stimulation. In patients with upper brainstem lesions, the TBR was normal, whereas the SBR was generally abnormal. The SBR was either absent or small and was significantly delayed with respect to control subjects. The opposite was the rule in patients with lower brainstem lesions who had delayed or absent TBR and no abnormal findings in the SBR. The SBR is mediated through circuits in the upper brainstem. Study of the SBR can be helpful in the neurophysiological assessment of patients with mesencephalic lesions.

Underlying neurological mechanisms associated with symptomatic convergence insufficiency.

Convergence insufficiency (CI) is the most common binocular vision problem, associated with blurred/double vision, headaches, and sore eyes that are exacerbated when doing prolonged near work, such as reading. The Convergence Insufficiency Neuro-mechanism Adult Population Study (NCT03593031) investigates the mechanistic neural differences between 50 binocularly normal controls (BNC) and 50 symptomatic CI participants by examining the fast and slow fusional disparity vergence systems. The fast fusional system is preprogrammed and is assessed with convergence peak velocity. The slow fusional system optimizes vergence effort and is assessed by measuring the phoria adaptation magnitude and rate. For the fast fusional system, significant differences are observed between the BNC and CI groups for convergence peak velocity, final position amplitude, and functional imaging activity within the secondary visual cortex, right cuneus, and oculomotor vermis. For the slow fusional system, the phoria adaptation magnitude and rate, and the medial cuneus functional activity, are significantly different between the groups. Significant correlations are observed between vergence peak velocity and right cuneus functional activity (p = 0.002) and the rate of phoria adaptation and medial cuneus functional activity (p = 0.02). These results map the brain-behavior of vergence. Future therapeutic interventions may consider implementing procedures that increase cuneus activity for this debilitating disorder.

Third nerve palsy: analysis of 1400 personally-examined inpatients.

BACKGROUND: Most studies of third nerve palsy (TNP) antedate computerized imaging and focus primarily on chart review of referral outpatients. METHODS: To compare a large contrasting population, I reviewed 1400 personally-examined municipal hospital inpatients with TNPs seen over 37 years. RESULTS: TNPs were bilateral in 11%, complete in 33%, without other neurological signs (isolated) in 36%, and associated with recurrent cranial neuropathies in 7%. Third nerve damage occurred in the subarachnoid space in 32%, the cavernous sinus in 23%, the brainstem in 14%, as a nonlocalized peripheral neuropathy in 18% and at an uncertain location in 13%. Causes were trauma (26%), tumor (12%), diabetes (11%), aneurysm (10%), surgery (10%), stroke (8%), infection (5%), Guillain-Barre and Fisher syndromes (5%), idiopathic cavernous sinusitis (3%), benign self-limited (2%), miscellaneous (4%), and unknown (3%). Local causes, besides an abundance of trauma, included six cases involving cysticercosis, four with wound botulism, and one with coccidiomycotic meningitis. Of 234 patients with diabetes, microvascular ischemia was the cause of TNP in only two-thirds (five had aneurysms) and 53% of those with diabetic microvascular ischemia had pupillary involvement-often bilateral, suggesting concomitant autonomic neuropathy. Only 2% of aneurysms spared the pupil. Apainful onset occurred with 94% of aneurysm and 69% of diabetic cases. CONCLUSIONS: Bilateral TNPs, multiple cranial neuropathies, and accompanying neurological signs were common among our inpatients, as were causes rare in outpatient settings such as severe trauma, transtentorial herniation, midbrain strokes, and the Guillain-Barre syndrome. Few cases remained undiagnosed and nondiabetic ischemia was rare.

Third Cranial Nerve Palsy Presenting with Unilateral Diplopia and Strabismus in a 24-Year-Old Woman with COVID-19.

BACKGROUND Coronavirus disease (COVID 19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and is the causative agent of a serious disease that is of great global public health concern. Palsy of the third cranial nerve is very rare in patients with confirmed 2019 novel coronavirus disease (COVID-19). We describe the case of a patient with an incomplete palsy of the left third cranial nerve sparing the pupils in the context of SARS-CoV-2 virus infection. CASE REPORT We report the case of a 24-year-old woman with confirmed COVID-19, which presented with acute onset of diplopia and strabismus of the left eye that occurred 3 days after the start of general symptoms. The patient had no significant medical history. Based on detailed ophthalmic and neurological examination, acute painless incomplete palsy of the third cranial nerve was suspected. Oculo-cerebral magnetic resonance angiography was unremarkable. Blood tests revealed mild normocytic regenerative anemia. According to the Moroccan recommendations, chloroquine and azithromycin were started. After what, a quick improvement of exotropia and diplopia was observed, and complete recovery was obtained by the sixth day of treatment. No adverse effects of the treatment were noted. CONCLUSIONS Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can cause neurological complications such as cranial nerve palsy. The pathological mechanism remains unclear. Full recovery of the ocular motricity is possible, and prognosis depends on the severity of the respiratory illness.

Congenital monocular elevation deficiency.

OBJECTIVE: The pathophysiology of monocular elevation deficiency is poorly understood. The goal of this study was to determine the appearance of the extraocular muscles and the oculomotor nerve. DESIGN: Observational case series. PARTICIPANTS: Six patients with monocular elevation deficiency. METHODS: Ophthalmologic examination and thin-sectioned magnetic resonance imaging (MRI) at the brainstem level as well as across the orbit in 6 patients were performed. MAIN OUTCOME MEASURES: Ocular alignment and movement, extraocular muscles, and the oculomotor nerve on MRI. RESULTS: One out of 6 patients with monocular elevation deficiency showed focal thickening of the inferior rectus muscle near the orbital apex. The 5 remaining patients showed normal extraocular muscles and the oculomotor nerves on MRI. CONCLUSIONS: Focal thickening of the inferior rectus muscle may partially explain the cause of restricted gaze. In addition, the finding of normal oculomotor nerves might support an underlying deficit in the unilateral center for upgaze as the etiology of monocular elevation deficiency.