Abnormal eye movements in unconscious patients serve as crucial diagnostic instruments, offering insights into the function of the central nervous system. Understanding these movements can aid in diagnosing the cause of unconsciousness, localizing brain lesions, and predicting outcomes. We report a patient who presented with spontaneous horizontal nystagmus unaffected by light in delayed post-hypoxic encephalopathy. Video-oculography showed exponentially increasing slow phases, with an amplitude ranging from 3° to 9° and a frequency of 0.5 Hz. Based on the results of oculography and neuroimaging, persistent horizontal nystagmus in our patient may be ascribed to an unstable neural integrator, possibly caused by disrupted cerebellar feedback mechanisms for horizontal gaze holding.
This study describes an unusual case of fluctuating unilateral high-frequency hearing loss with vertigo resembling Menière’s disease. The current diagnostic criteria for definite Menière’s disease include audiometrically documented low- to medium-frequency sensorineural hearing loss on at least one occasion before, during, or after an episode of vertigo. This case presented a diagnostic dilemma. Brain MRI was nonspecific, and a bithermal caloric test showed unilateral weakness of 44% on the affected side. The results of electrocochleography and cervical vestibular evoked myogenic potential tests were within the normal ranges. Persistent geotropic or ageotropic positional nystagmus was observed during each vertigo attack; the mechanism underlying this characteristic nystagmus needs further investigation.
Vertebrobasilar dolichoectasia (VBD) is a rare vascular condition characterized by the elongation, widening, and tortuosity of the vertebrobasilar artery. It can lead to various symptoms due to compression of cranial nerves and brainstem structures. We report a rare case of VBD presenting as sudden sensorineural hearing loss (SSNHL) with vertigo and spontaneous downbeat nystagmus in a 65-year-old woman with a history of hypertension. Magnetic resonance imaging revealed a tortuous and dilated right vertebrobasilar artery compressing the brainstem and left 8th cranial nerve root entry zone, without signs of acute cerebellar stroke. The compression of the anterior inferior cerebellar artery and cervicomedullary junction was also noted, suggesting a vascular cause for her symptoms. Following high-dose steroid treatment, the patient showed significant hearing improvement. This case underscores the importance of considering VBD in patients with unexplained SSNHL and vertigo, highlighting the role of detailed vascular imaging in the diagnosis and management of such cases.
A 54-year-old female patient presented with paroxysmal tinnitus and vertigo for 2 years, which have repeatedly occurred while rotating her neck, and lasted about 10 seconds. An anticonvulsant medication was prescribed with a diagnosis of microvascular compression syndrome on the 8th cranial nerve and audiovestibular evaluation and magnetic resonance imaging (MRI) scan were appointed a week later. In her next visit, she reported the disappearance of paroxysmal audiovestibular symptoms after medication. In the left ear, canal paresis and abnormal auditory brainstem response were observed. In MRI, a large meningioma in the cerebellopontine angle in the vicinity of the internal auditory canal orifice was detected, that was surgically resected by a neurosurgeon. After surgical removal of the tumor, she reported continuous dizziness due to vestibular nerve injury, but the paroxysmal attack of tinnitus and vertigo disappeared without anticonvulsant medication. This case suggests that an imaging study is mandatory when diagnosing microvascular compression syndrome on the 8th cranial nerve.
A 61-year-old male patient undergoing chemotherapy for esophageal cancer presented with symptoms of rightward tilting while both sitting and walking. A neurological examination revealed a head tilt, skew deviation with hypertrophy of the left eye, and a rightward shift in his gait. No spontaneous nystagmus was observed, and the vestibulo-ocular reflex was normal. Magnetic resonance imaging of the head revealed a suspected metastatic lesion in the right medial prefrontal cortex. Following the initiation of levetiracetam treatment, the patient demonstrated marked improvement, with the resolution of both head tilt and skew deviation within 1 month. Traditionally, the ocular tilt reaction has been attributed to unilateral or asymmetric dysfunction of the graviceptive pathways extending from the utricle to the upper midbrain lesions. However, this case highlights the potential involvement of the prefrontal cortex in the ocular tilt reaction. Further research is warranted on the role of the prefrontal cortex within the vestibular system.
Arnold Chiari malformation is a disease which is characterized by herniation of a portion of the cerebellum through the foramen magnum. Symptoms vary depending on the extent of the affected area, including posterior neck pain, upper limb pain, paralysis, paresthesia, weakness, dizziness, and ataxia. Among the patients presenting with dizziness, nystagmus is frequently observed, which is primarily characterized by down-beating nystagmus. We experienced a 42- years-old female patient presented with vertigo and gait disturbance, who were diagnosed with type 1 Arnold-Chiari malformation and treated by surgical decompression.
Intracranial dural arteriovenous fistula (dAVF) is characterized by an abnormal connection between branches of arteries and veins in the dura mater. Clinical manifestations of dAVF vary depending on their location, feeder arterial supply, amount of shunting, and most importantly, their venous drainage pattern. Acute vertigo has been rarely reported as an initial presentation of dAVF due to venous congestion in the brainstem. We report a patient who presented with acute right vestibulopathy without any brainstem signs in dAVF involving the transversesigmoid sinus. The patient showed abnormal caloric response but normal head impulse in the affected ear. Without any treatment, the patient’s symptoms gradually improved with a normalization of right canal paresis. Follow-up cerebral angiography also revealed a spontaneous regression of the shunt flow and reduction of venous drainage at the right transverse-sigmoid sinus. Based on the results of vestibular function tests and cerebral angiography, acute vertigo in our patient may be ascribed to impaired reabsorption of endolymph by focal venous congestion.
Ramsay Hunt syndrome occurs when the varicella zoster virus reactivates. Classic findings include the triad of facial paralysis, otic pain and herpetic lesions due to the pathogenesis associated with anterograde axonal reactivation of the varicella zoster virus in the geniculate ganglion. In addition to the classic triad, rare features such as a central type of vestibular function test may be observed due to the retrograde spread of the varicella zoster virus from the geniculate ganglion into the brain stem, including involvement of the vestibular nucleus. We present a case of Ramsay Hunt syndrome in a 57-year-old male patients, manifesting not only the typical triad of symptoms but also the unique features associated with brain stem involvement. This presented as direction-changing gaze-evoked nystagmus and a decrease in gain on both sides on video head impulse test. And brain magnetic resonance imaging showed a lesion in the vestibular nucleus of the brain stem.
Isolated infarcts of the pons (IIP) are a rare subtype of ischemic stroke, accounting for less than 1% of all strokes. It refers to a specific type of ischemic stroke that occurs within the pons region of the brain. IIP can be associated with vertebrobasilar insufficiency in certain cases. This case report describes a 64-year-old female patient who presented with acute vertigo and spontaneous nystagmus to the lesion side, ultimately diagnosed with IIP in the posterior right side of pons. Tegmental pontine infarcts typically manifest as oblique small (lacunar) infarctions that are localized in the mediolateral tegmental area of the middle to upper pons. The patient’s symptoms resolved spontaneously, but a 2-mm infarct was confirmed by brain diffusion magnetic resonance imaging. This case highlights the distinctive symptoms associated with IIP and emphasizes the importance of careful neurological examination and advanced neuroimaging techniques for accurate diagnosis.
Superficial siderosis (SS) is a rare neurodegenerative condition characterized by hemosiderin deposition in the central nervous system, which sometimes leads to sensorineural hearing loss and vestibular dysfunction. This case report details the diagnosis and treatment of a 63-year-old female patient presenting with a yearlong history of postural instability and recent symptoms of sudden right-sided hearing loss and imbalance. Physical examination and imaging revealed bilateral deafness and infratentorial SS. Treatment, including medication, vestibular exercises, high-dose steroids, and hyperbaric oxygen therapy, led to a significant alleviation of dizziness but no improvement in hearing. This case emphasizes the need for clinicians to consider SS in patients presenting with sudden-onset hearing loss and dizziness, even without prior any medical history or trauma, to accurately identify the underlying cause.
Distinguishing central and peripheral causes of dizziness is vital. A case is presented where a 42-year-old man with a history of posterior circulation ischemic stroke developed acute unilateral vestibulopathy with hearing loss. Clinical examination revealed signs of vestibular dysfunction on the left side. Audiometry confirmed deafness on the left, but imaging ruled out new central issues. The patient was diagnosed with audiovestibulopathy and treated with steroids, antiviral agents, intratympanic injections, and hyperbaric oxygen therapy. Hearing loss persisted, but dizziness improved with vestibular rehabilitation. Poststroke patients should be closely monitored for peripheral complications. Further research should explore the benefits of antiplatelet therapy in vascular-related conditions, even without clear central lesions.
Thiamine deficiency may cause Wernicke encephalopathy (WE) characterized by ataxia, ophthalmoplegia, and confusion. Aside from the triad of cardinal symptoms, selective or predominant impairments of bilateral horizontal canals may be observed in WE. Here, we report a patient with gastric mucosa-associated lymphoid tissue (MALT)-lymphoma complicated by an early stage of WE due to thiamine deficiency manifesting bilateral vestibular dysfunctions. A 78-year-old man recently diagnosed gastric MALT-lymphoma presented with dizziness and disequilibrium for several weeks. He showed mild imbalance while tandem walking and abnormal catch-up saccades bilaterally during bedside head impulse test (HIT). Video HIT revealed decreased vestibulo-ocular reflex gains with catch-up saccades for the bilateral horizontal and several vertical canals. Diagnostic work-up demonstrated decreased serum thiamine and lesions in the mammillary body and periaqueductal gray matter on brain magnetic resonance images. Furthermore, with thiamine replacement, his clinical symptoms were markedly improved. Also, vestibular symptoms and signs may be an early manifestation of WE, and video HIT could be a useful diagnostic tool to aid early detections.
Seesaw nystagmus (SSN) is characterized by conjugate torsional nystagmus with opposite vertical components in the two eyes. The waveform may be pendular or jerk (hemi-seesaw nystagmus, HSSN), in which the slow phase corresponds to one half-cycle and the quick phase to the other. Pendular SSN and HSSN have distinct clinical presentations and underlying causes. The pathophysiology of pendular SSN may be instability of visuovestibular interactions, while the underlying mechanism for HSSN may be related to the ocular tilt reaction or an imbalance in vestibular pathways. We report a patient with HSSN due to unilateral mesodiencephalic infarction that becomes apparent during visual fixation only.
Citations
Citations to this article as recorded by
Midbrain lesion-induced disconjugate gaze: a unifying circuit mechanism of ocular alignment? Maximilian U. Friedrich, Laurin Schappe, Sashank Prasad, Helen Friedrich, Michael D. Fox, Andreas Zwergal, David S. Zee, Klaus Faßbender, Klaus-Ulrich Dillmann Journal of Neurology.2024;[Epub] CrossRef
Coronavirus disease 2019 (COVID-19) spread rapidly and was declared a pandemic. In this situation, vaccination for COVID-19 is important and has been prompted in many countries. However, a number of adverse events have been reported for the Pfizer, Moderna, and AstraZeneca vaccines. Otolaryngologic adverse events after COVID-19 vaccination were reported, including several cases of sudden sensorineural hearing loss. Vestibular neuritis (VN) is an acute vestibular syndrome that causes acute and spontaneous vertigo due to unilateral vestibular deafferentiation, leading to nausea or vomiting and unsteadiness that can last from days to weeks. Neurotropism for the cochleovestibular nerve, immunoglobulin G mediated immune off-target reaction, and reactivation of latent viruses are hypothesized to be etiologies. Herein, the case of a 49-year-old female who developed VN after COVID-19 vaccination is presented. Although the association between VN and COVID-19 vaccination remains unclear, clinicians should be aware that VN may occur as an adverse event of COVID-19 vaccination.
A 29-year-old patient with diplopia showed a unilateral fourth nerve palsy combined with a Horner syndrome on the opposite side. Magnetic resonance images disclosed a focal hemorrhage in the left dorsal midbrain, affecting the nucleus of the fourth nerve and adjacent oculosympathetic fibers. Further evaluations including a bone marrow biopsy confirmed acute lymphoblastic leukemia. The combination of ocular motor and oculosympathetic palsy has a distinct localizing value. Fourth nerve palsy ipsilateral to Horner syndrome locates lesion in the cavernous sinus, while contralateral fourth nerve palsy locates the lesion in the midbrain.