Self-Recording of Eye Movements in Amyotrophic Lateral Sclerosis Patients Using a Smartphone Eye-Tracking App.

Introduction: Amyotrophic lateral sclerosis (ALS) can affect various eye movements, making eye tracking a potential means for disease monitoring. In this study, we evaluated the feasibility of ALS patients self-recording their eye movements using the "EyePhone," a smartphone eye-tracking application.

Methods: We prospectively enrolled ten participants and provided them with an iPhone equipped with the EyePhone app and a PowerPoint presentation with step-by-step recording instructions.

Burden of serious harms from diagnostic error in the USA.

Background: Diagnostic errors cause substantial preventable harms worldwide, but rigorous estimates for total burden are lacking. We previously estimated diagnostic error and serious harm rates for key dangerous diseases in major disease categories and validated plausible ranges using clinical experts.

Objective: We sought to estimate the annual US burden of serious misdiagnosis-related harms (permanent morbidity, mortality) by combining prior results with rigorous estimates of disease incidence.

Impact of Clinician Training Background and Stroke Location on Bedside Diagnostic Test Accuracy in the Acute Vestibular Syndrome - A Meta-Analysis.

Objective: Acute dizziness/vertigo is usually due to benign inner-ear causes but is occasionally due to dangerous neurologic ones, particularly stroke. Because symptoms and signs overlap, misdiagnosis is frequent and overuse of neuroimaging is common. We assessed the accuracy of bedside findings to differentiate peripheral vestibular from central neurologic causes.

Sudden unilateral hearing loss and vertigo following isolated cerebellar hypoperfusion without infarction due to vertebral artery dissection.

Background: The definition of sudden sensorineural hearing loss (SSNHL) is broadly accepted as acute sensorineural hearing loss of more than 30 dB over at least three consecutive frequencies in a pure-tone audiogram (PTA). Acute audiovestibular loss is common with ischaemic stroke in the territory of the anterior inferior cerebellar artery (AICA). However, cases in which SSNHL and vertigo occur with hypoperfusion alone are very rare.

Eye and Head Movement Recordings Using Smartphones for Telemedicine Applications: Measurements of Accuracy and Precision.

Objective: Smartphones have shown promise in the assessment of neuro-ophthalmologic and vestibular disorders. We have shown that the head impulse test results recorded using our application are comparable with measurements from clinical video-oculography (VOG) goggles. The smartphone uses ARKit's capability to acquire eye and head movement positions without the need of performing a calibration as in most eye-tracking devices.

Opinion and Special Articles: Remote Evaluation of Acute Vertigo: Strategies and Technological Considerations.

Patients with acute vestibular disorders are often a diagnostic challenge for neurologists, especially when the evaluation must be conducted remotely. The clinical dilemma remains: Does the patient have a benign peripheral inner ear problem or a worrisome central vestibular disorder, such as a stroke? The use of a focused history and the virtual HINTS (head impulse test, nystagmus evaluation, and test of skew) examination are key steps towards correctly diagnosing and triaging the acute vertiginous patient. When looking for signs of vestibulo-ocular dysfunction, there are important technological and practical considerations for an effective clinical interpretation.

VOR gain calculation methods in video head impulse recordings.

Background: International consensus on best practices for calculating and reporting vestibular function is lacking. Quantitative vestibulo-ocular reflex (VOR) gain using a video head impulse test (HIT) device can be calculated by various methods.

Objective: To compare different gain calculation methods and to analyze interactions between artifacts and calculation methods.

Rate of diagnostic errors and serious misdiagnosis-related harms for major vascular events, infections, and cancers: toward a national incidence estimate using the "Big Three".

Background: Missed vascular events, infections, and cancers account for ~75% of serious harms from diagnostic errors. Just 15 diseases from these "Big Three" categories account for nearly half of all serious misdiagnosis-related harms in malpractice claims. As part of a larger project estimating total US burden of serious misdiagnosis-related harms, we performed a focused literature review to measure diagnostic error and harm rates for these 15 conditions.

Serious misdiagnosis-related harms in malpractice claims: The "Big Three" - vascular events, infections, and cancers.

Background Diagnostic errors cause substantial preventable harm, but national estimates vary widely from 40,000 to 4 million annually. This cross-sectional analysis of a large medical malpractice claims database was the first phase of a three-phase project to estimate the US burden of serious misdiagnosis-related harms. Methods We sought to identify diseases accounting for the majority of serious misdiagnosis-related harms (morbidity/mortality).

Transient Vestibulopathy in Wallenberg's Syndrome: Pathologic Analysis.

Objective: To report an unusual lateral medullary stroke (LMS) associated with transient unidirectional horizontal, nystagmus, and decreased horizontal vestibulo-ocular reflex (h-VOR) gain that mimicked a peripheral vestibulopathy. MRI suggested involvement of caudal medial vestibular nucleus (MVN); however, the rapid resolution of the nystagmus and improved h-VOR gain favored transient ischemia without infarction. Decreased h-VOR gain is expected with peripheral vestibular lesions within the labyrinth or superior vestibular nerve; less frequently lateral pontine strokes involving the vestibular root entry, the vestibular fascicle, or neurons within the MVN may be responsible.

Neuroimaging "HINTS" of the Lateral Medullary Syndrome.

A series of neuroimaging studies illustrates many of the key findings of the lateral medullary syndrome.

Impact of artifacts on VOR gain measures by video-oculography in the acute vestibular syndrome.

Objective: The video head impulse test (HIT) measures vestibular function (vestibulo-ocular reflex [VOR] gain - ratio of eye to head movement), and, in principle, could be used to make a distinction between central and peripheral causes of vertigo. However, VOG recordings contain artifacts, so using unfiltered device data might bias the final diagnosis, limiting application in frontline healthcare settings such as the emergency department (ED). We sought to assess whether unfiltered data (containing artifacts) from a video-oculography (VOG) device have an impact on VOR gain measures in acute vestibular syndrome (AVS).

Adaptation and Compensation of Vestibular Responses Following Superior Canal Dehiscence Surgery.

Objective: To describe vestibulo-ocular function and compensatory mechanisms in the immediate postoperative period after superior canal dehiscence surgery.

Study Design: Prospective longitudinal study.

Setting: Tertiary medical center.

The video head impulse test during post-rotatory nystagmus: physiology and clinical implications.

The aim of this study was to test the effects of a sustained nystagmus on the head impulse response of the vestibulo-ocular reflex (VOR) in healthy subjects. VOR gain (slow-phase eye velocity/head velocity) was measured using video head impulse test goggles. Acting as a surrogate for a spontaneous nystagmus (SN), a post-rotatory nystagmus (PRN) was elicited after a sustained, constant-velocity rotation, and then head impulses were applied.

Compensatory saccades benefit from prediction during head impulse testing in early recovery from vestibular deafferentation.

The head impulse test (HIT) can identify a deficient vestibulo-ocular reflex (VOR) by the compensatory saccade (CS) generated once the head stops moving. The inward HIT is considered safer than the outward HIT, yet might have an oculomotor advantage given that the subject would presumably know the direction of head rotation. Here, we compare CS latencies following inward (presumed predictable) and outward (more unpredictable) HITs after acute unilateral vestibular nerve deafferentation.

An unusual stroke-like clinical presentation of Creutzfeldt-Jakob disease: acute vestibular syndrome.

Introduction: Vertigo and dizziness are common neurological symptoms in general practice. Most patients have benign peripheral vestibular disorders, but some have dangerous central causes. Recent research has shown that bedside oculomotor examinations accurately discriminate central from peripheral lesions in those with new, acute, continuous vertigo/dizziness with nausea/vomiting, gait unsteadiness, and nystagmus, known as the acute vestibular syndrome.

Quantifying the vestibulo-ocular reflex with video-oculography: nature and frequency of artifacts.

Video-oculography devices are now used to quantify the vestibulo-ocular reflex (VOR) at the bedside using the head impulse test (HIT). Little is known about the impact of disruptive phenomena (e.g.

VOR gain by head impulse video-oculography differentiates acute vestibular neuritis from stroke.

Objective: Vestibular neuritis is often mimicked by stroke (pseudoneuritis). Vestibular eye movements help discriminate the two conditions. We report vestibulo-ocular reflex (VOR) gain measures in neuritis and stroke presenting acute vestibular syndrome (AVS).

Vestibular signs of thiamine deficiency during the early phase of suspected Wernicke encephalopathy.

Non-encephalopathic presentations of CNS thiamine deficiency may be difficult to diagnose. We describe neuro-otologic findings of Wernicke syndrome in 5 patients with vestibular manifestations. Diagnosis was confirmed by low serum levels, response to replacement, and brain MRI to exclude other causes.

HINTS outperforms ABCD2 to screen for stroke in acute continuous vertigo and dizziness.

Objectives: Dizziness and vertigo account for about 4 million emergency department (ED) visits annually in the United States, and some 160,000 to 240,000 (4% to 6%) have cerebrovascular causes. Stroke diagnosis in ED patients with vertigo/dizziness is challenging because the majority have no obvious focal neurologic signs at initial presentation. The authors sought to compare the accuracy of two previously published approaches purported to be useful in bedside screening for possible stroke in dizziness: a clinical decision rule (head impulse, nystagmus type, test of skew [HINTS]) and a risk stratification rule (age, blood pressure, clinical features, duration of symptoms, diabetes [ABCD2]).

Early adaptation and compensation of clinical vestibular responses after unilateral vestibular deafferentation surgery.

Objective: To describe vestibulo-ocular function in the immediate postoperative period after unilateral vestibular deafferentation from vestibular schwannoma resection.

Study Design: Prospective longitudinal study.

Setting: Tertiary medical center.