The Opal: Pushing the Boundaries of Parkinson’s Disease Research

Thought LeadersDr. Kristen SowalskyTechnical Sales ManagerAPDM Wearable Technologies

An interview with Kristen Sowalsky, DC, Ph.D., from APDM Wearable Technologies at SfN 2018, discussing the Opal wearable sensor and its impact on Parkinson’s disease research.

What does APDM stand for, and where did the journey start for the company?

APDM began in 2007 when Dr. James McNames, Professor and Chair of Electrical and Computer Engineering at Portland State University, was looking to develop an unobtrusive wearable sensor that could log high bandwidth data from people with Parkinson's Disease.

Man with parkinsonStandard store88 | Shutterstock

Dr. McNames partnered with Dr. Mateo Aboy and Andrew Greenberg to co-found the company with the goal of developing this technology providing it to other researchers. The name APDM, which stands for Ambulatory Parkinson's Disease Monitoring, was chosen based on this initial inspiration and application.

Dr. Fay Horak, a Professor of Neurology at OHSU and expert in Parkinson's Disease rehabilitation, became involved after receiving a grant from Andy Grove’s Kinetics Foundation to develop a system to quantify balance and gait for clinical trials.

The 3 founders of APDM saw the value in this which lead to the beginning of a long-standing collaborative effort with Dr. Horak resulting in the development of the Mobility Lab gait and balance analysis system.

What is the Opal and why is it useful for monitoring patients with Parkinson’s Disease?

The Opal is an inertial measurement unit; it's our foundational technology that is used in all of our commercially available solutions. Each unit contains two tri-axial accelerometers, a magnetometer, and a gyroscope to capture raw inertial data and provide orientation tracking.

Our sophisticated software programs contain built-in algorithms which are specific to gait and balance analysis. We have also instrumented additional standard clinical tests to further aid in the assessment of Parkinson's Disease and other movement disorders.

Opal Sensor

How do the sensors work? How reliable is the data?

The sensors operate together in one wireless network with precise time synchronization. Our most popular system (Mobility Lab) employs six sensors, a docking station, and an access point which are connected to a laptop running our software.

The software allows the administrator to create custom folders for a particular subject group or project, then enter the desired patient data in the subject-profile. The administrator then selects the tests that they'd like to perform under the subject’s profile, places the sensors on the subject, and begins the test.

Tests typically take between 30 seconds to 2 minutes, but we also provide open-ended and customizable tests which administrators can create for themselves.

Our built-in tests come with instructions for the administrator and instructions to read out loud to each subject to ensure that the data are collected consistently. The process is simple; hit start,  have the subject perform the test, then hit stop. The system then provides an instant report with a variety of validated outcome measures that are specific to each particular test.

Validation is something we take very seriously and carry out internally by comparing our data to data from what are typically called, "Gold standard techniques" in the field. These can be optical motion-capture systems, gait mats, or force plates. We also have an external validation process with third-parties, who typically do a similar type of comparison and publish the results in peer-reviewed journals.  

What disease stage can the Opal be used to study?

One of the reasons we have received a lot of attention from pharmaceutical companies for clinical trials is the potential of our technology to objectively detect disease symptoms early on and track progression over time throughout the course of a variety of diseases.

For example, we’ve recently been working on a collaborative spinal cerebellar ataxia study with Dr. Christopher Gomez, Chair of Neurology at the University of Chicago, in which early signs of gait dysfunction were detected and related to the standard scale for the assessment and rating of ataxia (SARA).

With our technology, we aim to relate our objective measurements to accepted clinical scales in the field, yet identify biomarkers that may be detected earlier and more accurately than in subjective tests. These markers can be tracked over time to observe disease progression, or to understand the clinical efficacy of treatments provided.

How could the technology help patients with gait abnormalities?

What's great about our technology is that it not only detects an overall dysfunction of gait but that it also breaks this information down. We have over 100 validated measures specific to gait and balance that researchers can assess in relation to a specific population or on a patient-specific level.

This allows researchers to identify which parameters of balance or gait dysfunction are contributing to overall disability and suggests areas to target for therapeutic development. All of this data is being used to improve our understanding of Parkinson’s disease and improve patients’ quality of life.

It is now widely recognized that every patient is unique and that personalized medicine is the future. How could the Opal be used to personalize treatments?

Personalized medicine, in the form of continuous monitoring, is our main R&D focus at APDM. As our name indicates (“ambulatory”), it has been on our mind since day one. Currently, we are trying to understand what, when, and how long to deploy continuous monitoring solutions for movement disorders.

It is actually a very difficult problem, however, because to personalize solutions require a large dataset of high-quality data, emphasis on quality, which means multiple medical grade devices at different locations of the body (not just the wrist).

As you add more sensors and more days of monitoring compliance begins to plummet, therefore, we are hyper-focused on knowing the minimum number of sensors, days, and locations for each disease (and stage of disease). We’re lucky that we have strong pharmaceutical partners who we are working with to answer these questions.

Holding hands - parkinsonPhotographee | Shutterstock

APDM have analyzed over 25,000 patients using the Opal. What insights have you gained about Parkinson’s disease from all of this data?

The Opal has accelerated the field of Parkinson's disease research because of how quickly data can be captured. It's easy to use, and the results are produced right away; compared to the time-consuming process of having to go to an optical motion capture lab and rely on a specialized team to process the data and provide results.

The system is also portable, meaning more people including rural populations can be reached. The more data that is collected and the faster the research process is performed, the quicker you can bring potential treatments to the field.

In addition, the Opal provides a new way of looking at the parameters we use to diagnose Parkinson’s disease and quantifying them. This could potentially allow us to further refine the diagnosis of the disease.

For example, Dr. Fay Horak and her research team recently discovered that bradykinesia may be detected earlier in turning in PD than as assessed in standard UPDRS testing. Quantification of turns using Opals with the Mobility Lab system demonstrated that PD patients turn more slowly with more steps when compared to controls.

Can this technology be applied to other conditions that affect movement?

Absolutely. We’ve recently deployed our newest release, Moveo Explorer - Full Body Kinematic System into the field of biomechanics for a wide variety of applications including sport performance, injury prevention, ergonomics, and more.

We also continue to apply our technology to additional populations including Multiple Sclerosis, ALS, Cerebral Palsy, Huntington’s disease, dementia, vestibular disorders, mTBI, and Stroke. We are excited that our technology allows us to help many along the whole spectrum of human movement from neurodegenerative disease to performance enhancement.

Where can readers find more information?

All publications by APDM.

About Kristen Sowalsky

Headshot of Kristen SowalskyDr. Kristen Sowalsky’s initial training in human movement began with a bachelor’s degree in Exercise Physiology, followed by a doctorate in Chiropractic medicine.

After 6 years in rehab-focused clinical practice, she was inspired to further her education and went on to receive her Ph.D. in Applied Neuromechanics at the University of Florida.

During her Ph.D. program, while studying gait and balance in Parkinsonian disorders, she became acquainted with APDM as she utilized the V1 Mobility Lab system for her dissertation project.

Her current multifaceted role at APDM in both R&D and sales enables her to steer the direction of applied product development and help customers determine how APDM systems can enhance their work.

About APDM Wearable Technologies

APDM Wearable Technologies is a digital health company focused on developing and commercializing digital endpoints for neuroscience and balance disorders. APDM has raised $13MM+ from the NIH and Department of Defense, has over 500+ publications and thousands of researchers worldwide using our technology.


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