C. Light announces FDA 510(k) clearance of Retitrack

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Advance your practice today with pioneering retinal tracking technology

Meet the Retitrack™

Defining oculomotor function with the first compact 510(k) FDA-cleared retinal-tracking monitor that measures saccades & fixation

Objective Oculometrics in 10-seconds

Track and record fixational eye movement (FEM) videos in the retina at the photoreceptor level

Advanced Motion Pattern Analysis

Extract FEM patterns from recordings to assess saccadic and fixational metrics like speed, magnitude, and accuracy

Comprehensive Longitudinal Tracking

Analytics report for clinicians to visualize and quantify an individual's oculomotor health and visual experience over time

CPT Code Reimbursement

Dedicated CPT code to facilitate timely and accurate insurance reimbursement for specialized services

eye motion matters.

Fixational eye motion (FEM) are microscopic, involuntary eye movements that allow for precision vision. Traditionally, FEMs are subdivided into three categories: microsaccades, ocular drift, and tremor.

Today's problem in healthcare.

Healthcare faces challenges with available bedside tools to accurately and objectively track and assess fixational eye movements (FEM).


MRIs and bedside clinical exams currently do not offer the level of specificity required to assess these microscopic ocular motor movements at the photoreceptor level.

C. Light's solution.

Our smart platform acutely records and analyzes micro-oculometric FEM patterns extracted from our Retitrack™ retinal videos.


The goal of our solution is to provide an objective method to digitally capture and catalogue distinct FEM patterns accurately to aid healthcare providers in their clinical decision-making, as well to supplement their current toolkit.


To be the
trusted leader
in eye-tracking solutions



C. Light is a healthtech company on a mission to create AI-enabled technology to assess eye and brain health and aid early detection and earlier intervention for the future of healthcare.

We aim to empower clinicians who seek objective metrics to validate what the patient experiences. The future of C. Light’s pipeline is to aid healthcare providers deliver evidence-based, targeted care at the earliest stages via our eye-tracking tools.

Christy Sheehy, PhD
ceo + cofounder

Joe Xing, PhD
cto + cofounder

Jacqueline Theis, OD, FAAO
chief medical officer

Let's innovate, together.

C. Light is actively looking to partner with pharma, CROs, and patient advocacy groups to conduct biomarker research for our future pipeline in the following therapeutic areas.

Research has shown that early detection of neurodegenerative disease, like Alzheimer's disease (AD) and mild cognitive impairment (MCI), is crucial for the development of effective therapies to help slow progression and prevent irreversible brain damage [1].

How eye-tracking may help

Recent research reveals altered saccades and fixational eye movement (FEM) patterns in individuals with MCI/AD, including changes in latency, directionality, accuracy, and error correction during saccades [2,3,4], as well as prolonged fixation duration [5,6] and abnormal microsaccadic direction [7].

These eye movement abnormalities are linked to cognitive impairment, aiding in dementia/MCI subtype differentiation [6,7,8], progression prediction, and tracking AD advancement [9], potentially reflecting deficits in attention control [10] and neural degeneration in structures like the prefrontal cortex, brainstem, and cerebellum [11,12,13].

Research studies have shown that eye-tracking offers potential as an objective tool for prognostication and monitoring of multiple sclerosis (MS) progression, surpassing the specificity limitations of MRI [14] and clinical exams [15].

How eye-tracking may help

In recent clinical research studies, fixational eye motion (FEM) analysis in MS patients reveals distinct patterns — including increased microsaccades, amplified vertical amplitude, and specific eye movement anomalies (e.g. nystagmus and square-wave jerks) [16,17]. The findings from this research suggests that (the combination of) these distinct patterns could offer earlier and more precise detection of the most subtle motor changes, potentially before conventional bedside examinations can detect them [16].

Additionally, microsaccade features were seen in research to be significantly associated with clinical and paraclinical measures of MS disability including the EDSS scoring system, suggesting that FEM monitoring could provide objective quantification and insight into an individual's motor function at the micron level [15,16].

A traumatic brain injury (TBI) occurs when a direct or indirect force to the head or body causes damage to the brain [17,18]. Research has shown that having vestibular-oculomotor dysfunction at the time of injury poses as a significant risk factor for developing persistent post-concussion symptoms (syndrome) which can delay recovery time [19,20,21].

How eye-tracking may help

Researchers have shown that many patients with concussion exhibit impaired oculomotor function including: smooth pursuit eye movements (SPEMs), saccadic eye movements, convergence insufficiency, and fixational stability [22]. Recently, research has shown that concussed patients demonstrated significantly greater mean fixational microsaccade amplitude, velocity, and acceleration compared with age- and gender-matched controls [23].

Additionally, FEM metrics were shown to be associated with clinical measures of concussion including PCSS, ImPACT, and Vestibular/ Ocular Motor Screening (VOMS) assessment [24]. Specifically, research outcomes showed VOMS outcomes having the highest magnitude of correlations between average saccade amplitude and VOMS’ symptoms of nausea, as well as the average instantaneous drift speed with ImPACT’s visual memory score, respectively [24].

Retinal disease impacts millions of individuals worldwide, leading to visual impairment and ultimately vision loss [25,26]. In research, impairment of eye movements and fixation have been observed in (1) individuals with retinal disease, particularly those diseases that directly impact the macula [27,28,29,30] and (2) diabetes [27,28,32].

In recent research from UC Berkeley, individuals with macular disease demonstrated higher fixation instability, larger amplitudes of slow drifts and microsaccades, and lower drift velocities when compared with older adults with normal vision [33].

Disclaimer: This research is not intended to reflect the ability of the current iteration of Retitrack™ described in 'What We Deliver' nor provide any implication outside of what the FDA clearance (May 2023) states for indications for use of Retitrack™.

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science-backed innovation for healthcare.

Christy Sheehy, PhD

Chief Executive Officer

Dr. Christy Sheehy co-founded C. Light Technologies & is the inventor of the FDA cleared (for marketing) product, Retitrack™.
She is an award-winning entrepreneur and healthcare innovator and published vision scientist with over 15 years of technical entrepreneurial expertise and direct clinical research experience with neurodegenerative patient populations at the top research institutions of UC Berkeley and UCSF. 
Dr. Sheehy successfully acted as the Principal Investigator for three NIH SBIR/STTR grants to study fixational eye motion changes in concussion and multiple sclerosis, and has brought in >$8M from venture capital, angel, and grant funding to the company to-date.
Dr. Sheehy’s mission is to create digital solutions using the retina to inform on brain health and improve prognostic care in all aspects of healthcare and sports vision performance.

Joe Xing, PhD

Chief Technology Officer

Dr. Joe Xing co-founded C. Light and  20 years of experience in data science, machine learning, and artificial intelligence for smart optical design and related technologies.
Joe emerges as the strategic force to spearhead C. Light’s future growth in technology. His interests lies in leveraging cutting-edge technologies — such as artificial intelligence, machine learning, and data analytics — to drive C. Light’s innovation engine.
He leads the development and implementation of C. Light’s technology to academic and research institutions, clinics, and other medical offices. 
Joe is a part of Stanford University’s Y-Combinator and is an avid cyclist and golfer who enjoys life on the gravel and on the green.

Jacqueline Theis, OD

Chief Medical Officer

Jacqueline Theis, OD, FAAO is an award-winning optometrist with residency training in neuro-optometry and oculomotor dysfunction from UC Berkeley. 
Dr. Theis is an internationally-recognized speaker, published author, and key-opinion leader in her field for the diagnosis & management of vision problems and oculomotor dysfunction in concussion, acquired brain injury, & neurodegenerative disorders (i.e. multiple sclerosis, myasthenia graves, Parkinson’s and Alzheimers disease).
Her mission is to bridge the care gap between primary care, neurology and optometry/ophthalmology, and revolutionize the field(s) with active clinical research on the oculomotor system as a biomarker for neurologic function.
She was the Asst. Clinical Professor and founding Chief of the UC Berkeley Sports Vision and Concussion Clinic & currently practices at Virginia Neuro-Optometry within a transdisciplinary brain injury clinic.  She is an active member of IES, AOA, and AAO.

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All your accurate, objective data to aid diagnosis

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10-sec Retitrack video scan of your eye.

Andrew Norton, PhD

VP, Optical Engineering

Andrew Norton, PhD is an optical engineer whose expertise lies in electrical engineering for adaptive optics and electro-optical technology development. He has a unique interest in wave optics and transforming the field of optics for use in neurologic spaces like MS, brain injury & TBI, and Alzheimer’s.
Andrew’s career has focused on developing state-of-the-art imaging systems for the visible, infrared & radar spectral bands.
Previously, he led the development of an experimental physics lab at Stanford University building high-resolution imaging systems & algorithms for ground-based astronomy telescopes & deep-tissue biological imaging applications.
Fun fact: Andrew has also designed a deployable large-aperture synthetic radar telescope for a stealth startup company & was the acting director of the Center for Adaptive Optics for 3 years!

Lon Dowell

Chief Commercial Officer

Lon Dowell is a dynamic sales and commercial executive leader who has cultivated 20+ years experience at the crossroads of healthcare, technology, and data.
With a strong background in the ophthalmologic sector, Lon’s expertise spans the domains of medical imaging, clinical workflow, and modality integration, establishing him as a distinguished authority and a sought-after speaker. His proficiency extends beyond individual contributions, as he excels in building & leading teams, propelling them towards the company’s overarching vision and the successful execution of business objectives.
Lon reflects the capability to navigate and thrive in a rapidly evolving industry landscape. He practices Business Philosophy that is focused on implementing a culture of responsibility: applying course corrections based on data & upfront success criteria models.

Tracy Tran

Director, Investor Relations & Marketing

Tracy Tran has a diverse background spanning from clinical research management and operations for top research and academic institutions to life sciences and healthcare consulting for big pharma.
With a deep-rooted passion for healthcare technology and a multi-faceted perspective of the healthcare industry, Tracy recognizes C. Light’s immense potential to transform (primary) patient care.
Prior to joining C. Light, Tracy clinically trained at UC San Francisco and managed local and international clinical trials in retinal and neurodegenerative diseases for the Department of Neurology. Her previous clinical work aimed to address the pressing unmet needs felt in conditions where early symptoms often go undetected. She received her BA in Molecular & Cellular Biology from UC Berkeley.
For C. Light, Tracy takes on tasks related to investor relations & strategic partnerships, marketing, PR, and clinical research mgmt.

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Physicians neuro toolkit can’t capture it .