Objective Mobile diagnostics for Optic Neuropathies

Neurofieldz, Inc., Newton MA

Investigators

Abstract

Diseases of the afferent visual system are central to the practice of neuro-ophthalmology (N-O). Visual function often dictates type of treatment, but screening exams are a burden on already stretched neuro-ophthalmic clinics. Therefore, there is an unmet need for a practical, rapid, sensitive test that is objective and provides quantitative functional endpoints for early diagnosis and monitoring response to newly developed treatments for neuro-ophthalmic diseases. NeuroFieldz has developed NeuroVEP, a breakthrough portable wireless sensor system with a new technique called Electric Field Encephalography, measuring visual evoked potentials (VEP) at the visual cortex in response to custom visual stimulus patterns presented on a head mounted smartphone display. Neuroelectric recordings are analyzed for full-field stimulus (ffVEP) and 62 sectors of the visual field (multi-focal, mfVEP). Extensive previous development has resulted in a near final prototype validated with 200+ case studies in macular degeneration, glaucoma, multiple sclerosis (MS) and optical neuritis. A pilot study of ON / MS patients demonstrated the superiority of the NeuroVEP system over a conventional wired clinical system in terms of portability and ease of use, superior VEP results, in addition to providing mfVEP visual field results. Hypothesis and Objective We hypothesize that ffVEP and mfVEP analysis using the NeuroVEP, when accurately targeted, measured, and analyzed, can provide detailed objective neuro-ophthalmic diagnostic information on neurovisual impairments associated with diseases of the afferent visual system. This Phase I SBIR project aims to conduct a feasibility study for the use of the NeuroVEP system for diagnosis and staging of N-O diseases. Specific Aim 1: Develop custom tests for ON and validate on 100 normal subjects and 100 patients. Task 1: Paradigm development of 62 sector background pattern-onset VEP and validation on 100 naïve normal subjects (200 eyes). Task 2: mfVEP validation using synthetic defects with blocked sectors. Task 3: Test-retest to verify repeatability. Task 4: Acquire NeuroVEP test results on 100 N-O subjects (200 eyes) diagnosed with diseases of the afferent visual system. Subjects will undertake a battery of tests including patient consenting, ff/mfVEP using NeuroVEP, corrected visual acuity (Snellen), AP and OCT. Specific Aim 2: Machine learning based analysis of VEP signals and develop a diagnostic analysis score for staging neuro- ophthalmic diseases. Obtain multiple metrics including 6 parameters for ffVEP and >22 features for mfVEP including latency and amplitude of P100 for each individual eye and calculating inter-ocular and inter- hemisphere latency differences and amplitude ratios from the ff/mfVEP results. Extract additional distinguishing metrics using advanced signal processing methods including discrete wavelet transform for classification criteria to distinguish between normal, early and late stage N-O subjects. The ff/mfVEP results will be correlated with AP, OCT, and clinical variables using comprehensive multi-variate statistical analysis for a complete validation of NeuroVEP.