A Middle-Aged Man With Diplopia, Headache, and Hyperglycemia.

A 60-year-old man with a history of diabetes mellitus and hypertension presented with diplopia and vertigo for two days. These symptoms had a gradual onset, were progressive, and were associated with a headache that had been present for 15 days. His blood sugar level was 376 mg/dl. His convergence and ability to adduct when looking laterally were affected bilaterally. Additionally, he presented with right exotropia on primary gaze and no ptosis. Brain imaging was normal. Following the rest of the work-up, diabetes mellitus was independently established as the cause of bilateral internuclear ophthalmoplegia in this patient. High blood sugar affects the brain at the molecular level by causing vascular damage, oxidative stress, and decreasing neuroplasticity.

A Rare Presentation of Posterior Circulation Strokes: A Case Report of Nine Syndrome.

Nine syndrome is a rare variant of one-and-a-half syndrome that results from a stroke in the posterior circulation, mainly manifesting as ipsilateral horizontal gaze palsy, facial palsy, and contralateral hemiataxia. Awareness of the clinical signs of this syndrome is crucial for accurate localization of the lesion and guiding further investigations. We report a case of nine syndrome presenting with signs of one-and-a-half syndrome, ipsilateral facial nerve palsy, hemiataxia, and hemiparesis. There are only a few cases of nine syndrome reported in the literature.

Insight Into Uncommon Territory: Exploring Internuclear Ophthalmoplegia in Artery of Percheron Infarct.

Internuclear ophthalmoplegia (INO), a neurological disorder is characterized by horizontal gaze palsy because of a lesion in the medial longitudinal fasciculus, a neural pathway that is mainly responsible for coordinating the movements of the eye. INO presents with diplopia and impaired adduction of the affected eye, accompanied by abducting eye nystagmus. The condition also arises from different etiologies which include multiple sclerosis, encephalitis, Lyme disease, HIV, and herpes zoster. Artery of Percheron (AOP) infarction is a subtype of bilateral thalamic infarction that poses a unique form of diagnostic perplexity due to its varied and often non-specific clinical manifestations such as altered responsiveness, memory disturbances, and oculomotor deficits. Here we discuss a 53-year-old female who presented with INO in the context of an AOP infarct. Under this context, the clinical finding includes some paradigms like nystagmus, anisocoria, and bilateral ptosis. Magnetic resonance imaging confirmed an acute infarct in the AOP territory, which supplies the rostral midbrain and paramedian thalami. This case emphasizes the critical importance of meticulous clinical evaluation and the utilization of advanced imaging techniques in diagnosing rare stroke syndromes like AOP infarction. Management of the patient included dual antiplatelet therapy to prevent further thromboembolic events and supportive care to address the immediate neurological deficits. Early recognition and prompt treatment are crucial for better patient outcomes. Long-term management focuses on the secondary prevention of stroke through lifestyle modifications, medical therapy, and regular monitoring. Education on uncommon stroke syndromes and continued research are essential for enhancing the accuracy of diagnosis and efficacy of treatment which ultimately leads to better patient care and prognosis.

Medial longitudinal fasciculus (MLF)-syndrome in a multimorbid patient with alcohol use disorder: a case report.

Background: Patients with multiple comorbidities can present as a diagnostic challenge as overlapping symptomatology complicates the discovery of emergent pathology. Symptoms of alcohol misuse or orthostatic hypotension may especially cloud the diagnosis of insidious neurological disease, such as posterior circulation infarct. With a growing elderly population, it is expected that the complex multimorbid patient will represent a growing challenge to prompt stroke detection and treatment. Case Description: Herein, we present a 69-year-old male with a history of alcohol abuse, chronic obstructive pulmonary disease, type 2 diabetes mellitus, paroxysmal atrial fibrillation, and congestive heart disease. The patient arrived at our emergency department with dizziness, ataxia, and diplopia. His symptoms had a sudden onset and gradual exacerbation over a span of 2 days, notably aggravated by standing and walking, but relieved when seated or supine. Notably, a month before admission, the patient had been treated with anti-congestive medications for severe congestive heart failure leading to a weight loss of 55 lbs over period of 2 weeks. The initial differential diagnoses were orthostatism, Wernicke's encephalopathy (WE), and ischemic stroke. Magnetic resonance imaging (MRI) revealed a subacute infarct in the medial longitudinal fasciculus (MLF). Conclusions: The case underscores the challenge in diagnosing neurological conditions in multimorbid individuals. The combination of various underlying conditions may drastically complicate the diagnosis. Successful diagnosis and treatment necessitates meticulous evaluation of clinical observations, medical history, current medications, and pertinent diagnostic evaluations to effectively narrow down the potential differential diagnoses.

Eight-and-a-Half Syndrome Secondary to Acute Brainstem Infarction.

Eight-and-a-half syndrome is a rare neuro-ophthalmologic condition, which is characterized by ipsilateral horizontal gaze palsy, internuclear ophthalmoplegia (INO), and ipsilateral lower motor neuron facial palsy. We report a case of eight-and-a-half syndrome secondary to acute brainstem infarction. A 55-year-old gentleman with underlying diabetes mellitus and hypertension presented with a sudden onset of double vision in the right lateral gaze for one day. On examination, there was a limitation in the left eye horizontal eye movement with limited right eye adduction. Further neurological examination revealed left lower motor neuron facial nerve palsy. Magnetic resonance imaging (MRI) of the brain showed an acute infarct involving the left side of the thalamus extending to the left side of the midbrain, pons, and medulla. He was diagnosed with eight-and-a-half syndrome secondary to acute brainstem infarction. The patient was referred to the neuromedical team, where he was treated with anti-platelet medications. He showed gradual improvement on follow-up and had complete resolution of ophthalmoplegia after three months. There was only minimal residual facial nerve weakness. Eight-and-a-half syndrome has a localizing value to the dorsal tegmentum of the pons. It requires thorough neurological examination and imaging studies for accurate diagnosis and management. This case highlights the potential for a significant recovery in patients with eight-and-a-half syndrome when timely and appropriate treatment is administered.

Neuro-Behçet's Syndrome Without Genital Ulcers: A Case Report and Literature Review.

Behçet's disease is a rare multisystemic vasculitis characterized by oral ulcers, genital ulcers, and skin and ocular lesions. Neuro-Behçet's syndrome is a condition in which individuals with Behçet's disease experience neurological symptoms that cannot be attributed to other neurological diseases. We present a rare case of neuro-Behçet's syndrome with acute internuclear ophthalmoplegia and deteriorating neurological function with a prior history of recurrent oral ulcers with pathergy-like features, acneiform papulopustular rash, retinal hemorrhages, and recurrent epididymitis without genital ulcers. Patient improved with cyclophosphamide. This case underscores the importance of diagnosing and managing neuro-Behçet's syndrome in the absence of genital ulcers.

Internuclear Ophthalmoplegia Following COVID-19 with Abnormal Findings on Neuroimaging; A Case Report.

COVID-19 had been reported to be associated with neuro-ophthalmic complications. However, there is a shortage of evidence regarding internuclear ophthalmoplegia (INO) presentation after COVID-19 infection with related brain magnetic resonance imaging (MRI). Herein, we report a case of INO in a 69-year-old woman with presentation of diplopia following COVID-19 infection, along with her neuroimaging. We concluded that it is important to recognize the possibility of INO in patients with diplopia after COVID-19 and to consider brain MRI as an informative tool in these patients.

Successful Management of Acute Streptococcal Meningoencephalitis Complicated by Bilateral Third-Nerve Palsies, Wall-Eyed Bilateral Internuclear Ophthalmoplegia, Blindness, and Deafness: Case Report.

Introduction: Streptococcal meningoencephalitis (SME) is a rare, and frequently lethal, acute infection, and inflammation of the central nervous system parenchyma, with associated meningeal involvement. Bacterial meningoencephalitis is generally associated with high rates of morbidity and mortality, despite available antimicrobial and corticosteroid treatments. While Streptococcus pneumoniae is well recognised to cause bacterial meningitis, direct extension into the central nervous system parenchyma is rare. Case Presentation: A previously well 49-year-old man presented with sudden onset severe headache, fevers, neck stiffness, and reduced consciousness. The manifestations of SME in this patient were bilateral pupil-involving third-nerve palsies, wall-eyed bilateral internuclear ophthalmoplegia (WEBINO), bilateral blindness, bilateral deafness, a right lower motor neuron facial palsy, and upper motor neuron signs in his limbs. Initially, a partial response to high dose intravenous antibiotics occurred, but with administration of intravenous corticosteroids, further substantial resolution of the patient's neurological and neuro-ophthalmological deficits occurred. Conclusion: This case highlights the benefit of multidisciplinary diagnostic and therapeutic interventions in a case of SME complicated by bilateral pupil-involving third-nerve palsies, WEBINO, bilateral blindness, bilateral deafness, a right lower motor neuron facial palsy, and upper motor neuron signs. It appears to be the first reported case of SME with this rare collection of neuro-ophthalmological abnormalities.

Internuclear ophthalmoplegia following radial artery cardiac catheterization approach: An unusual presentation.

Internuclear ophthalmoplegia (INO) may happen following percutaneous coronary intervention and angiography. However, no reports of INO during radial artery angioplasty were reported yet. We report a rare case in a 47-year-old man presenting with diplopia after radial artery angioplasty. Although the symptoms were resolved after 60 days, diagnosing this obstacle is necessary to reduce the patient and physician's anxiety.

One-and-a-Half Syndrome in a Case of Brainstem Bleed.

One-and-a-half syndrome (OHS) is a horizontal gaze palsy in one direction with internuclear ophthalmoplegia (INO) in the other. The only eye movement possible is the abduction of the contralateral eye with nystagmus. The usual structures affected are the medial longitudinal fasciculus and paramedian pontine reticular formation or the abducens nucleus. Most commonly, the OHS is caused by ischemia and demyelinating lesions. The other causes include infectious, neoplastic, and rarely traumatic. We report a case of a 42-year-old non-compliant hypertensive female who presented with giddiness, projectile vomiting, and right-sided hemiparesis and was found to have OHS on cranial nerve examination in the emergency department (ED). In the ED, the presence of complete horizontal gaze palsy in one direction with INO in the other direction should raise suspicion of a brainstem pathology.

Internuclear ophthalmoplegia as a presentation of procedural stroke: a case report.

BACKGROUND: Cardiac catheterization and endovascular procedures are extensively used in modern medicine, and procedural stroke is one of the major complications that the catheterization laboratory team may face in their everyday work. Recognizing the signs and symptoms of procedural stroke is crucial to ensuring appropriate management. We herein report a case of internuclear ophthalmoplegia that caused blurred vision, diplopia, and dizziness on lateral gaze as an unusual presentation of procedural stroke. CASE PRESENTATION: A 60-year-old Thai woman underwent right partial colectomy and was diagnosed with stage IV diffuse large B-cell lymphoma. Pre-chemotherapy echocardiography revealed mild left ventricular systolic dysfunction, and she therefore underwent diagnostic catheterization. Coronary angiography revealed normal coronary arteries, leading to a diagnosis of non-ischemic cardiomyopathy. After the procedure, she immediately developed dizziness and diplopia. During the right lateral gaze, she exhibited impaired adduction of the left eye and horizontal nystagmus of the right eye. A diagnosis of left internuclear ophthalmoplegia was made. Magnetic resonance imaging revealed a tiny area exhibiting characteristics of an acute infarct in the left paramedian midbrain, including the left medial longitudinal fasciculus, which explained the clinical picture. Another region of restricted diffusion indicating an acute infarct was detected in the right inferior cerebellar hemisphere. Magnetic resonance angiography revealed no significant cerebral artery disease. The patient achieved full neurological recovery 6 weeks after symptom onset. CONCLUSION: This report describes an uncommon presentation of procedural stroke that is likely to be misdiagnosed, especially by medical staff unfamiliar with internuclear ophthalmoplegia. Despite the good prognosis of internuclear ophthalmoplegia, appropriate stroke care is crucial in patients with procedural stroke because of the risk of multiple brain infarcts.

Relative contribution of lateral vestibular neuron and abducens internuclear neuron inputs to the discharge activity of medial rectus motoneurons.

Medial rectus motoneurons mediate nasally directed horizontal eye movements. These motoneurons receive two major excitatory inputs, from the abducens internuclear neurons (ABD Ints) and neurons of the lateral vestibular nucleus whose axons course through the ascending tract of Deiters (ATD). In the present work, we have recorded in the alert chronic cat preparation the discharge activity of these two premotor neurons simultaneously with eye movements, to discern their relative contribution to the firing pattern of medial rectus motoneurons. ABD Int discharge was accurately correlated with eye movements, displaying high sensitivities to eye position and eye velocity. ATD neurons also discharged in relation to spontaneous and vestibular eye movements but showed significantly lower eye position and eye velocity sensitivities. Outstandingly, ATD neurons presented a significantly lower eye position threshold for recruitment compared to both ABD Ints and medial rectus motoneurons. Therefore, ATD neurons exhibited eye position and velocity signals during spontaneous and vestibular eye movements, which were of lower magnitude than those of ABD Ints, but due to their low recruitment threshold, they could play a significant role in facilitating ABD Int signal transmission onto medial rectus motoneurons.

Pure Isolated Internuclear Ophthalmoplegia as Presentation of Midbrain Ischemic Stroke: A Case Report.

Internuclear ophthalmoplegia (INO) is a condition characterized by impaired ocular movement, leading to an inability to perform coordinated lateral gaze, resulting in ophthalmoplegia. This impairment results from damage to the medial longitudinal fasciculus (MLF), which can occur because of various types of lesions localized in the pons or midbrain. In this case, we report on a 67-year-old man with multiple comorbidities who arrived at the emergency department with complaints of sudden dizziness and an unsteady gait. During the examination, he exhibited left INO, which was characterized by limited left eye adduction and multidirectional nystagmus of the right eye when performing right lateral gaze.

A Case Report on Pseudo-Internuclear Ophthalmoplegia: A Rare Manifestation of Myasthenia Gravis.

A 41-year-old male with recently diagnosed diabetes mellitus type 2 presented with drooping of the left eyelid with double vision and was found to have an adduction deficit in the left eye and nystagmus in the abducting right eye during conjugated gaze: a left-sided internuclear ophthalmoplegia (INO). A medial longitudinal fasciculus (MLF) lesion was excluded exhaustively with brain imaging. The possibility of a pseudo-INO was considered. The autoantibody profile demonstrated positivity to acetylcholine receptor (AChR) antibody. Repetitive nerve stimulation (RNS) and electromyography (EMG) were unremarkable. An acetylcholinesterase inhibitor trial showed a significant improvement in the ocular symptoms. Hence, the diagnosis of ocular myasthenia was confirmed. There was no evidence of a thymic hyperplasia. Herein, we discuss pseudo-INO being an atypical presentation of myasthenia gravis (MG), emphasizing the importance of having a strong suspicion despite unremarkable test results.

Case report: A disconjugate pattern in video head impulse testing hints toward a central cause of acute vertigo.

When acute vertigo occurs, the challenge for the medical practitioner lies in the focused assessment to find the cause of its symptoms. Especially in the case of central pathology, a fast diagnosis is essential for therapy. The head impulse, nystagmus, test of skew (HINTS) protocol and the additional video head impulse test (VHIT) can distinguish between central and peripheral vestibular causes in the acute setting and thus help to set the right path for further evaluation and treatment. In this case, a patient with acute onset of vertigo presented with an unusual pattern in the VHIT. Binocular eye tracking showed a disconjugate horizontal vestibulo-ocular reflex (VOR) with severe loss or gain for the adducting eye yet with a lack of corrective saccades. The abducting eye produced a pattern of mild VOR gain loss yet with pronounced corrective saccades. Together with clinical findings that were compatible with internuclear ophthalmoplegia, a probable central lesion in the medial longitudinal fasciculus (MLF) region was suspected. The patient was sent to a tertiary hospital, where the initial MRI was negative, but due to additional neurological symptoms occurring later, multiple lesions in the cervical spine and cerebellum were detected. The hypothesis of an inflammatory demyelinating disease of the central nervous system (CNS) was made. A further workup led to the final diagnosis of neurosarcoidosis. In a retrospective neuroradiologic assessment, an alteration compatible with a non-active demyelinating lesion in the MLF was detected on secondary imaging as a probable cause of the initial pathophysiologic finding. In this report, we aimed to highlight the unusual case of a disconjugate VOR as a distinctive VHIT pattern hinting toward a central cause of acute vertigo that clinicians should be aware of.

Bilateral Internuclear Ophthalmoplegia Caused by Dengue Fever.

A 22-year-old male was referred from the medicine department with the chief complaint of double vision for 2 months. The patient had suffered from dengue viral hemorrhagic encephalitis for 2 months for which intensive medical care was given. On ocular examination, both eyes (OU) showed limited adduction with contralateral abducting nystagmus on attempted horizontal gaze. Magnetic resonance imaging of brain showed pontine and midbrain hemorrhages which involved the region of medial longitudinal fasciculus and caused bilateral internuclear ophthalmoplegia (INO). Bilateral INO is very rare and most commonly caused by multiple sclerosis. The presentation of dengue fever causing midbrain and pontine hemorrhages which resulted in bilateral INOs has not been previously reported, to our knowledge.

Wall-Eyed Bilateral Internuclear Ophthalmoplegia as an Early Presentation of Multiple Sclerosis.

Wall-eyed bilateral internuclear ophthalmoplegia (WEBINO) is a rare neuro-ophthalmological condition in which there is ocular motility impairment characterized by bilateral adduction deficiencies, bilateral abducting nystagmus, and exotropia in primary gaze, and is often associated with multiple sclerosis (MS). This report describes a young female who presented with sudden onset of binocular diplopia and alternating exotropia for two days duration, which was associated with a history of intermittent headaches for one year before presenting complaints. Examination revealed alternating exotropia on the primary gaze with bilateral limitation of adduction and bilateral nystagmus on abduction. Other ocular and neurological examinations were unremarkable. Neuroimaging showed multiple white matter lesions that were consistent with demyelinating disease. Her symptoms completely resolved after the initiation of intravenous corticosteroid therapy. However, she developed left upper limb numbness four months later, and a repeat magnetic resonance imaging (MRI) of the brain showed the presence of multiple new brain lesions. Subsequently, she was diagnosed with MS and started on immunotherapy. Her symptoms resolved, with no residual ophthalmoplegia or any neurological symptoms.

Eight-and-a-half syndrome as manifestation of acute disseminated adenovirus encephalomyelitis.

Acute disseminated encephalomyelitis is an immune mediated inflammatory-demyelinizing disease that usually manifests after infection or vaccination in school-age children. It typically presents a prodromal phase with flu-like symptoms, followed by a phase with varied clinical symptoms, neuro-ophthalmological alterations such as ophthalmoplegia or optic neuritis may occur. The differential diagnosis includes tumor, vascular, infectious, inflammatory and demyelinating diseases. Diagnosis is based on the clinical history and the characteristics of brain magnetic resonance imaging, the gold standard test. The study of the cerebrospinal fluid can help to guide the clinical picture. The prognosis is favorable, with an excellent response to corticosteroids and immunoglobulins, with minimal long-term sequelae in most cases. We report the case of an 8-year-old male with acute demyelinating disease due to adenovirus whose manifestation was an eight-and-a-half syndrome.

Internuclear Ophthalmoplegia as an Isolated Symptom of Brainstem Wake-up Stroke Responsive to Intravenous Thrombolysis: Evidence from MRI.

BACKGROUND: Internuclear ophthalmoplegia (INO) is a disorder of eye movements caused by a lesion involving the medial longitudinal fasciculus (MLF) within the brainstem, and it is characterized by adduction impairment combined with contralateral dissociated abduction nystagmus. The frequency of acute ischemic stroke (AIS) presenting with INO as a predominant symptom is very low, and many patients suffering from this brainstem AIS are precluded from intravenous thrombolysis (IVT). OBJECTIVE: To provide for the first time a magnetic resonance imaging (MRI) evidence of response to the IVT in brainstem wake-up stroke presenting with INO as an isolated symptom. METHODS: Here, we described a rare case of pons AIS presenting with INO as a unique symptom of awakening. In order to differentiate an ischemic stroke from other stroke mimics, and to determine whether the patient was within the therapeutic window for IVT (wake-up stroke), brain MRI including DWI and FLAIR sequences was acquired. RESULTS: A left paramedian pontine DWI/FLAIR mismatch was detected and the patient was considered eligible for IVT. After IVT, the patient made a full recovery with complete resolution of INO. Follow-up MRI at 1 month demonstrates the absence of ischemic lesions. CONCLUSION: Our case provides neuroradiological evidence of IVT efficacy in brainstem stroke, and it should prompt clinicians to rapidly perform MRI in wake-up onset INO and to just as quickly administer IVT, since INO is a functionally disabling deficit. Finally, this case demonstrates the value of MRI in diagnostic, prognostic, and therapeutic workup of posterior circulation wake-up stroke.