Parkinson’s patients now have a light for their path – literally, which is providing a hands free way to improve freedom to walk with less freezing and shuffling.
Visual Cueing Spectacles (MCS), a combination of a central field cueing device with spectacles, gives Parkinson’s patients a virtual path to step over thereby increasing step length, studies show.
VCS, prototypes by Enhanced Vision Systems under a licensing agreement from HMD Therapeutics, is for patients suffering from akinesia. Prior to VCS, patients in the community were resorting to getting a nudge to start walking, marching to a cadence, rocking the body, walking over objects and walking to music, just to “unfreeze”.
The spectacles create the phenomenon known as, kinesia paradoxa, which allows patients to move more naturally by providing obstacles or an illusion of obstacles at their feet for them to step over.
In a study recently published by the Department of Veterans Administration, Journal of Rehabilitation Research and Development, VCS, has been found to decrease the shuffling and freezing gait of PD patients suffering from akinesia. VCS may be worn over their own prescription glasses and has been designed with a light-emitting diode display on one side that generates stationary horizontal lines of light on the ground in front of the patient, much like rungs on a ladder. As the patient raises their head slightly to look out ahead of their feet, the lines appear - giving the wearer a virtual walking surface or “step over” target as they walk forward. When they look straight ahead, the light display turns itself off but then reappears if participants’ heads tilt downward toward their feet.
Orlando Regional Medical Center neurologist Dr. Mark Klafter, president elect of the Florida Society of Neurology, senior partner for Neurological Services of Orlando, and former director of National Parkinson’s Foundation Care Centers, Orlando- 1998-2001, said although he isn’t familiar with the spectacles, he is well familiar with and endorses the concept of visual cues.
“With Parkinson’s disease there is a deficiency in their dopamine levels. That dopamine is especially involved in initiating movement- thinking to doing and thinking to saying, ‘ Klafter said. “If they can’t go from thinking to walking they’ll have significant deficiencies and as a result they fall. If they can have a visual cue - another way to initiate their movement -it often helps them over that barrier. The patient is then working with alternative pathways through the nervous system, instead of thinking to moving; they’re also going from seeing to moving. By recruiting other pathways in their central nervous system, they are able to initiate their gait.”
Lead author and primary researcher on the study, Tatiana Kaminsky, called the results “moderately successful”.
“This is not the first study that’s been done with them. It s just the first study that was done in the community with them,” Kaminsky said. “Up until now they were only tested in a laboratory environment. This study only had six participants, so you can’t say it was revolutionary, but it was encouraging. All of the participants said it was helpful to them. It didn’t necessarily stop the freezing, but it enabled them to get themselves out of it more easily.”
Kaminsky said study participants reported feeling more confident in knowing that if they get stuck they can get themselves out of it. Freezing gait typically occurs about 10 years after onset of PD and increases the risk for falls. The prevalence of akinesia ranges from 32 to 60 percent among people with PD. It’s worse when patients feel stressed, pressured, or are in a doorway, elevator, or other narrow space.
“This was the first time these glasses had been taken out of a lab environment into the real world,” Kaminsky said. “It was small but it was the next phase of the study because people don’t live in labs. We wanted to know if the things we see in the lab carried over into the real world. There haven’t been any studies in the community because it’s very complicated. You can’t control things like you can in a lab”
PD patient Tom Riess, former podiatrist and inventor of the spectacles, said he came up with the idea when he developed a freezing and festinating gait.
“I first noticed that I didn’t have these problems while walking up or down stairs,” Riess said. “I discovered that there was something about the visual cadence of the stairs that was gait enabling. After much experimentation and observation I realized that the same effects could be obtained by using marks or cues on the floor - for example playing cards spaced at stride length intervals and stepping over them like rungs of a ladder. Unfortunately there are no playing cards on the floor in real life environments so I wondered if these cues couldn’t be made portable, available on demand in a socially acceptable package i.e. glasses that would project these cues on the floor. I eventually hooked up with the Human Interface Technology Lab, a virtual reality research center where we applied for and received an NIH grant to do a proof of concept study.”
Klafter said as former director of Parkinson’s Foundation Care Centers, Orlando, he was involved with a three-year project sponsored by National Parkinson’s Foundation and different centers throughout the state with goals to reduce PD hospital admissions and nursing home transfers. The idea was to reduce cost related to falls.
“One of the things we found was that patients that have visual cues are less likely to fall when they are initiating their gait. The majorities that do fall, do it when they are starting to walk, turning or getting up so this had pivotal implications in public health costs, the economic component, and quality of life for the patient,” Klafter said. “When we increase the medications, there are obviously side effects. Sometimes it’s impossible to avoid an increase in medications and we’d simply go with techniques to try and keep them safer. What I often tell my patients is to step over line in the flooring so if there is a pattern on the carpet or tile they step over. Another thing I sometimes order for them is a cane or walker with a laser pointer, but those aren’t always approved by their insurance. They are very expensive, but work very well. So if the visual cueing spectacles aren’t very expensive and if they can get them without having to fill out a lot of forms and their gait and safety can be enhanced, risk of failing reduced and healthcare costs reduced, it will help on a micro-encompassing basis.”
Riess said he received prototypes for testing from Enhanced Vision Systems periodically and a commercial version of the glasses are now being developed. “We are very close — maybe weeks- away from going into production,” Reiss said.