Ocular Motor Nerve Palsy After Traumatic Brain Injury: A Claims Database Study.

BACKGROUND: Traumatic brain injury (TBI) is one of the common causes of ocular motor nerve (oculomotor nerve [CN3], trochlear nerve [CN4], and abducens nerve [CN6]) palsies, but there has been no large study of ocular motor nerve palsy caused by TBI. This study aimed to investigate the characteristics of and differences in ocular motor nerve palsy after TBI, according to patient age and severity of TBI. METHODS: This was a population-based retrospective cohort study that included patients who had ocular motor nerve palsy after TBI with ≥6 months of continuous enrollment using claims data from the IBM MarketScan Research Databases (2007-2016). We assessed sex, age at the first diagnosis of TBI, the severity of TBI, and the rates of strabismus procedures according to the age and severity of TBI. The rates of muscle transposition surgery and chemodenervation in CN3, CN4, and CN6 palsy were investigated. RESULTS: A total of 2,606,600 patients with TBI met the inclusion criteria. Among them, 1,851 patients (0.071%) had ocular motor nerve palsy after TBI. The median age of the patients was 39 (Q1-Q3: 19-54) years, and 42.4% of the patients were female. The median continuous enrollment period after the first diagnosis of TBI was 22 (Q1-Q3: 12-38) months. Of the 1,350,843 children with TBI, 454 (0.026%) had ocular motor nerve palsy. Of the 1,255,757 adults with TBI, 1,397 (0.111%) had ocular motor nerve palsy. Among these 1,851 patients, CN4 palsy (697, 37.7%) occurred most frequently, and strabismus procedures were performed in 237 patients (12.8%). CN6 palsy developed most frequently in children. More children (16.5%) underwent strabismus surgeries than adults (11.6%) ( P = 0.006). The proportion of CN4 palsy (52.3%) was higher while the proportion of CN3 palsy (15.5%) was lower in patients with mild TBI than in patients with moderate-to-severe TBI ( P < 0.001). CONCLUSIONS: CN4 palsy developed most frequently among patients of all ages, and only approximately 13% of the patients underwent strabismus procedures for ocular motor nerve palsy after TBI. The rate of development of ocular motor nerve palsy was approximately 4.3 times lower in children than adults, and children most frequently had CN6 palsy after TBI.

Misdiagnosis of Third Nerve Palsy.

BACKGROUND: This study identifies the diagnostic errors leading to misdiagnosis of 3rd nerve palsy and to aid clinicians in making this diagnosis. The objective of this article is to determine the incidence of misdiagnosis of 3rd cranial nerve palsy (3rd nerve palsy) among providers referring to a tertiary care neuro-ophthalmology clinic and to characterize diagnostic errors that led to an incorrect diagnosis. METHODS: This was a retrospective clinic-based multicenter cross-sectional study of office encounters at 2 institutions from January 1, 2014, to January 1, 2017. All encounters with scheduling comments containing variations of "3rd nerve palsy" were reviewed. Patients with a documented referral diagnosis of new 3rd nerve palsy were included in the study. Examination findings, including extraocular movement examination, external lid examination, and pupil examination, were collected. The final diagnosis was determined by a neuro-ophthalmologist. The Diagnosis Error Evaluation and Research (DEER) taxonomy tool was used to categorize the causes of misdiagnosis. Seventy-eight patients referred were for a new diagnosis of 3rd nerve palsy. The main outcome measure was the type of diagnostic error that led to incorrect diagnoses using the DEER criteria as determined by 2 independent reviewers. Secondary outcomes were rates of misdiagnosis, misdiagnosis rate by referring specialty, and examination findings associated with incorrect diagnoses. RESULTS: Of 78 patients referred with a suspected diagnosis of 3rd nerve palsy, 21.8% were determined to have an alternate diagnosis. The most common error in misdiagnosed cases was failure to correctly interpret the physical examination. Ophthalmologists were the most common referring provider for 3rd nerve palsy, and optometrists had the highest overdiagnosis rate of 3rd nerve palsy. CONCLUSIONS: Misdiagnosis of 3rd nerve palsy was common. Performance and interpretation of the physical examination were the most common factors leading to misdiagnosis of 3rd nerve palsy.

Clinical Characteristics for Predicting Recovery of Acquired Fourth Cranial Nerve Palsy.

BACKGROUND: Fourth cranial nerve palsy is the most common disease diagnosed in patients with vertical diplopia. Although it is reported to present a good prognosis, there are currently no agreed on prognostic factors that anticipate the recovery of the palsy other than the etiology. The purpose of this study was to investigate the prognostic factors of acquired fourth cranial nerve palsy. METHODS: The medical records of consecutive patients diagnosed with acquired unilateral fourth cranial nerve palsy from 2010 to 2020 and followed up for ≥6 months were retrospectively reviewed. The cause and degree of palsy, ocular deviation (horizontal, vertical, and cyclo), and fundus torsion were reviewed. The cause of palsy was classified as ischemic, traumatic, intracranial mass, others, or idiopathic. Patients were divided into 2 groups according to palsy recovery: complete recovery (group CR) or not CR (group NCR). The clinical characteristics of the 2 groups were compared, and the risk factors for incomplete recovery were investigated. RESULTS: Thirty-five patients (25 men) were included in the study. The average age was 55.94 ± 16.11 years. CR was achieved in 23 patients (65.7%), and the time to recovery was 3.91 ± 4.03 months. The most common cause was traumatic (40.0%), followed by ischemia (37.1%), intracranial mass (11.4%), others (8.6%), and idiopathic (2.9%). The degree of palsy and fundus torsion was significantly higher in group NCR (P = 0.010 and P = 0.001). Severe oculomotor limitation, large fundus torsion, and intracranial mass cause rather than ischemic cause indicated a higher risk of incomplete or no recovery (P = 0.016, P = 0.009, and P = 0.043). CONCLUSION: Identifying whether a patient has an intracranial mass, severe oculomotor limitation, or large fundus excyclotorsion may be useful for predicting the recovery of acquired unilateral fourth cranial nerve palsy.

Acute Complete Oculomotor Nerve Palsy in a Young Male Due to a Skull Base Myofibroma.

ABSTRACT: A 25-year-old male patient visited the ophthalmology clinic because of upper eye lid ptosis in the right eye, binocular double vision, and light sensitivity. He was diagnosed with a complete third nerve palsy caused by a skull base myofibroma, a rare clinical entity that has not been described before in oculomotor nerve palsy.

Failure to Obtain Urgent Arterial Imaging in Acute Third Nerve Palsies.

BACKGROUND: Isolated third nerve palsy may indicate an expanding posterior communicating artery aneurysm, thus necessitating urgent arterial imaging. This study aims to assess the rate and duration of delays in arterial imaging for new isolated third nerve palsies, identify potential causes of delay, and evaluate instances of delay-related patient harm. METHODS: In this cross-sectional study, we retrospectively reviewed 110 patient charts (aged 18 years and older) seen between November 2012 and June 2020 at the neuro-ophthalmology clinic and by the inpatient ophthalmology consultation service at a tertiary institution. All patients were referred for suspicion of or had a final diagnosis of third nerve palsy. Demographics, referral encounter details, physical examination findings, final diagnoses, timing of arterial imaging, etiologies of third nerve palsy, and details of patient harm were collected. RESULTS: Of the 110 included patients, 62 (56.4%) were women, 88 (80%) were white, and the mean age was 61.8 ± 14.6 years. Forty (36.4%) patients received arterial imaging urgently. Patients suspected of third nerve palsy were not more likely to be sent for urgent evaluation (P = 0.29) or arterial imaging (P = 0.082) than patients in whom the referring doctor did not suspect palsy. Seventy-eight of 95 (82%) patients with a final diagnosis of third nerve palsy were correctly identified by referring providers. Of the 20 patients without any arterial imaging before neuro-ophthalmology consultation, there was a median delay of 24 days from symptom onset to imaging, and a median delay of 12.5 days between first medical contact for their symptoms and imaging. One patient was harmed as a result of delayed imaging. CONCLUSIONS: Third nerve palsies were typically identified correctly, but referring providers failed to recognize the urgency of arterial imaging to rule out an aneurysmal etiology. Raising awareness of the urgency of arterial imaging may improve patient safety.

Importance of the "Rule of the Pupil" in the Modern Neuroimaging Era.

ABSTRACT: The "Rule of the Pupil" states that when aneurysms compress the oculomotor nerve, a dilated or sluggishly reactive pupil will result. In previous decades, when cerebral angiography was required to detect an intracranial aneurysm, the "Rule of the Pupil" was used to determine the relative risk of angiography and the likelihood of aneurysmal compression in patients with third nerve palsies (3NPs). Noninvasive imaging including computed tomography angiography (CTA) and magnetic resonance angiography has become readily accessible and can detect all aneurysms large enough to cause 3NPs. It is therefore recommended that all patients with 3NP undergo neuroimaging regardless of pupil status because the consequences of missing an aneurysm are high. The question therefore remains as to whether the "Rule of the Pupil" still has relevance in today's era of modern neuroimaging. We describe a 73-year-old man who developed a left complete, pupil-sparing 3NP and was found to have a paraclinoid meningioma in the left cavernous sinus. As compressive lesions are expected to impair the iris sphincter muscle, no intervention was recommended and his 3NP spontaneously improved within 3 months. We also describe a 54-year-old woman with diabetes and a complete 3NP with a dilated, nonreactive pupil. Initial CTA was reported as normal, but re-review of imaging revealed a posterior communicating artery aneurysm and immediate intervention to coil the aneurysm occurred. The "Rule of the Pupil" is still important in the modern neuroimaging era as demonstrated in cases of incidentally found lesions along the course of the oculomotor nerve and missed radiological findings.

Recurrent Third Nerve Palsy Secondary to Instrinsic Schwannoma of the Third Cranial Nerve.

ABSTRACT: A 78 year-old woman has experienced multiple episodes of transient right third nerve palsy over the course of 15 years and has undergone multiple imaging studies as well as investigations for myasthenia gravis and giant cell arteritis in search for the diagnosis. When seen after the most recent episode, MRI with contrast and Fast-Imaging Employing Steady-State Acquisition protocol revealed a subtle enlargement and enhancement of the cisternal and proximal cavernous portions of the right third cranial nerve. An empiric diagnosis of schwannoma intrinsic to third cranial nerve was made. All patients with cyclical third nerve palsies should have appropriate neuroimaging to rule out subtle structural lesions before other investigations are undertaken.

Oculomotor Nerve Palsy Due to Unusual Causes.

BACKGROUND: An isolated oculomotor nerve (CN III) palsy is a diagnostic concern because of the potential for serious morbidity or life-threatening causes. We present 5 unusual causes of oculomotor nerve palsy that escaped initial diagnosis in order to raise awareness of their associated features that will facilitate correct diagnosis. METHODS: This study consisted of a retrospective analysis of clinical features and imaging of 5 patients who were referred for neuro-ophthalmologic evaluation with presumed diagnosis of oculomotor nerve palsy of unknown reasons. RESULTS: A complete CN III palsy and an inferior division CN III palsy were diagnosed with a schwannoma in the cavernous sinus and orbital apex portion, respectively; a middle-aged woman with aberrant regeneration was found to have a small meningioma; an adult man with ptosis was diagnosed with cyclic oculomotor paresis with spasms; and a patient after radiation was diagnosed with neuromyotonia. CONCLUSIONS: Localizing the lesion of oculomotor nerve palsy and careful examination of the imaging is crucial. Aberrant regeneration, cyclic pupil changes, and past medical history of amblyopia, strabismus, or radiation are also very helpful for diagnosis.

Four common diseases causing sudden blindness or death in the eye emergency department.

Neuro-ophthalmological emergency disorders typically present with symptoms of visual loss, diplopia, ocular motility impairment or anisocoria. The ocular manifestations of these disorders are sometimes indicative of a more serious global neurology disease rather than an isolated ocular disease. The aim of this review is to highlight four important neuro-ophthalmological emergency disorders that must not be missed by an ophthalmologist. These include acute painful Horner's syndrome, painful cranial nerve III palsy, giant cell arteritis and transient ischaemic attack with amaurosis fugax. The delayed diagnosis of these clinical entities puts the patient at risk of blindness or death. Therefore, prompt diagnosis and management of these conditions are essential. This can be acquired from understanding the main signs and symptoms of the disease presentation together with a high index of suspicion while working at a busy eye emergency department.

A Rare Case of Oculomotor Nerve Palsy after Endovascular Treatment in a Patient with Internal Carotid Artery Dissection.

BACKGROUND: The oculomotor nerve has two major fibers: the outer autonomic fiber innervates the ciliary muscles and sphincter pupillae involved in pupil constriction, and the inner somatic fiber innervates the levator palpebrae superioris in the eyelid and four extraocular muscles involved in oculomotor dysfunction. We present a rare case of oculomotor nerve palsy with internal carotid artery (ICA) dissection and discuss the vascular anatomical feature of interest to be considered during treatment. CASE REPORT: A 56-year-old man presented with language impairment, right visual field loss, and right-sided facial sensory loss, weakness, and hypesthesia 30 hours after the last seen normal. CT perfusion imaging revealed a large left middle cerebral artery distribution and possible salvageable ischemic penumbra. Angiography showed occlusion of the communicating segment of the left ICA. We performed mechanical thrombectomy for left ICA occlusion that led to partial recanalization after several attempts. A control digital subtraction angiography showed dissection features in the communicating part of the left ICA. The recanalized ICA got blocked again within ten minutes. Angioplasty was performed and the flow improved. Five hours after thrombectomy, the patient developed complete left oculomotor palsy with ptosis, a fixed mydriatic pupil, and lateral and downwards eyeball deviation suggesting oculomotor nerve palsy. MRI on the 23rd day after symptom onset revealed enhancement of the left oculomotor nerve. CONCLUSIONS: The clinical and imaging course described in this case shows an injury to the oculomotor nerve with compressive plus ischemic injury in a patient with ICA dissection who received endovascular treatment.

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.

Artery of Percheron infarction presenting as nuclear third nerve palsy and transient loss of consciousness: a case report.

BACKGROUND: Thalamic blood supply consists of four major vascular territories. Out of them paramedian arteries supply ipsilateral paramedian thalami and occasionally rostral mid brain. Rarely both paramedian arteries arise from a common trunk that arise from P1 segment of one sided posterior cerebral artery (PCA). This is usually due to hypoplastic or absent other P1 and this common trunk is termed Artery of Percheron (AOP). Its prevalence is in the range of 7-11% among the general population and AOP infarcts account in an average of 0.4-0.5% of ischemic strokes. Clinical presentation of AOP infarction is characterized by impaired arousal and memory, language impairment and vertical gaze palsy. It also can present with cerebellar signs, hemi paresis and hemi sensory loss. We herein present a case of AOP infarction presenting as transient loss of consciousness and nuclear third nerve palsy. CASE PRESENTATION: A 51 year old previously healthy male, was brought to us, with a Glasgow coma scale (GCS) of 7/15. GCS improved to 11/15 by the next day, however he had a persisting expressive aphasia. Right sided nuclear third nerve palsy was apparent with the improvement of GCS. He did not have pyramidal or cerebellar signs. Thrombolysis was not offered as the therapeutic window was exceeded by the time of diagnosis. Diagnosis was made using magnetic resonance imaging (MRI) that was done after the initial normal non-contrast computer tomography (NCCT) brain. He was enrolled in stroke rehabilitation. Aspirin and atorvastatin was started for the secondary prevention of stroke. He achieved independency of advanced daily living by 1 month, however could not achieve full recovery to be employed as a taxi driver. CONCLUSIONS: Because of the rarity and varied clinical presentation with altered levels of consciousness, AOP infarcts are easily overlooked as a stroke leading to delayed diagnosis. Timely diagnosis can prevent unnecessary investigations and the patient will be benefitted by early revascularization. As it is seldom reported, case reports remain a valuable source of improving awareness among physicians about this clinical entity.

Pseudopartial Third Nerve Palsy as the Presenting Sign of Ocular Myasthenia Gravis.

SIGNIFICANCE: This case emphasizes the high degree of suspicion necessary for a timely diagnosis of myasthenia gravis. PURPOSE: This report discusses a case of ocular myasthenia gravis presenting as a pseudo-third nerve palsy with ptosis. The pathogenesis, treatment, and management of ocular myasthenia gravis are discussed. CASE REPORT: A 68-year-old white man presented to our clinic after noticing a new right eyelid droop for several days and experiencing horizontal double vision for the past 3 weeks. A pupil-sparing partial third nerve palsy was diagnosed, and MRI and laboratory work were ordered to assist with diagnosis. Laboratory results demonstrated highly positive acetylcholinesterase antibodies, confirming a diagnosis of ocular myasthenia gravis. CONCLUSIONS: Myasthenia gravis commonly presents with ocular signs and symptoms. Because ocular myasthenia gravis can mimic other causes of diplopia, heightened awareness and suspicion are necessary to make a timely diagnosis.

Isolated Oculomotor Nerve Palsy - A Rare Initial Manifestation of Tuberculous Meningitis.

Tuberculous meningitis (TBM) is a sub-acute / chronic meningitis known for its diverse manifestations which may lead to delayed diagnosis. An isolated oculomotor nerve palsy as an initial presentation of TB meningitis is quite rare. One such case has presented here; A 18 year female presented to us with ptosis of the left eye. Complete neurological examination revealed it to be a case of isolated 3rd cranial nerve palsy. Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) brain revealed no significant abnormality. Cerebrospinal fluid (CSF) analysis was done and diagnosis of Tuberculous Meningitis was confirmed. This case report focuses on the fact that tuberculous meningitis should be included in the differential diagnosis of isolated oculomotor nerve palsy.

Case Report: Varicella-zoster Encephalitis with Acute Retinal Necrosis and Oculomotor Nerve Palsy.

SIGNIFICANCE: Varicella-zoster virus is a common cause of morbidity and vision loss in patients worldwide. It can affect any structure of the eye, from keratitis to acute retinal necrosis. Rapid diagnosis and treatment significantly improve clinical outcomes and quality of life. PURPOSE: The purpose of this study was to demonstrate a case where urgent referral to the emergency department was required to treat a patient with disseminated herpes zoster infection. CASE REPORT: This is a rare case of varicella-zoster virus encephalitis in a 70-year-old immunocompetent white man who initially presented to the eye clinic for vertical diplopia and floaters. He also had prior thoracic dermatomal rash, followed by new-onset headaches and cerebellar ataxia. Examination revealed a partial oculomotor nerve palsy in the right eye with bilateral optic disc edema and areas of retinitis consistent with acute retinal necrosis in both eyes. Polymerase chain reaction analysis of his aqueous humor and cerebrospinal fluid confirmed an active zoster infection. He received combination systemic and intravitreal antiviral medication until his retinitis resolved but required adjustments for recalcitrant disease and drug-induced nephrotoxicity. While on maintenance dosing of oral valacyclovir, he experienced reactivation in the form of bilateral vasculitis, which was successfully managed once restarting therapeutic oral dosing. CONCLUSIONS: This case describes a successful clinical course of acute retinal necrosis with strategies for its treatment in the setting of varicella-zoster encephalitis. Antiviral medication should be given as soon as possible, as prompt treatment has been shown to improve patient outcomes, although prognosis is typically poor in these cases. Multiple specialists are often needed to address different clinical challenges, including central nervous system involvement, viral strain resistance, disease reactivation, and drug toxicity.

Internal Carotid Artery Occlusion Causing Acute Cranial Neuropathies.

A 54-year-old male with a history of left posterior parietal ischemic stroke, epilepsy, tobacco and marijuana smoking, and alcohol abuse, presented with acute left visual loss and diplopia. On examination, he had reduced left visual acuity and a left oculomotor nerve palsy. CT angiogram from aortic arch to circle of Willis identified extensive thrombus occluding the left common and internal carotid arteries, extending to the left ophthalmic artery. This case demonstrates acute visual loss from ophthalmic artery occlusion, and left oculomotor nerve palsy from occlusion of the inferolateral trunk of the internal carotid artery (cavernous sinus portion).

Sudden-onset unilateral ptosis induced by pituitary Macroadenoma, with false-positive jolly and neostigmine tests.

The development of ptosis as a consequence of pituitary tumor is an exceptionally rare occurrence. Here, we describe the case of sudden-onset unilateral ptosis induced by pituitary macroadenoma. The condition was characterized by false-positive Jolly and neostigmine tests. These findings mimic oculomotor nerve palsy and make the correct diagnostics rather challenging. The case points to the fact that patients with acquired ptosis need detailed neuroophthalmological examination.

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.

Approach to a Patient with Diplopia in the Emergency Department.

BACKGROUND: Diplopia can be the result of benign or life-threatening etiologies. It is imperative for the emergency physician to be proficient at assessing diplopia and recognize when urgent referral or neuroimaging is required. OBJECTIVE: The first part of this review highlights a simple framework to arrive at the appropriate disposition of diplopic patients presenting to the emergency department (ED). The second part of this review provides more detail and further management strategies. DISCUSSION: ED strategies for assessment of diplopia are discussed. Management strategies, such as when to image, what modality of imaging to use, and urgency of referral, are discussed in detail. CONCLUSIONS: Unenhanced plain computed tomography (CT) of the head or orbits is largely not useful in the work-up of diplopia. Magnetic resonance imaging is preferred for ocular motor nerve palsies. Due to limited resources in the ED, patients with isolated fourth and sixth nerve palsies with the absence of other neurological signs on examination should be referred to Neurology or Ophthalmology for further work-up. All patients presenting with an acute isolated third nerve palsy should be imaged with CT and CT angiography of the brain to rule out a compressive aneurysm. Contrast-enhanced CT imaging of the brain and orbits would be indicated in suspected orbital apex syndrome or a retro-orbital mass, thyroid eye disease, or ocular trauma. CT and CT venogram should be considered in cases of suspected cavernous sinus thrombosis. In any patient over the age of 60 years presenting with recent (1 month) history of diplopia, inflammatory markers should be obtained to rule out giant cell arteritis.