New technology addresses dryness, headache caused by misalignment
“I would have never put together that a person with symptoms such as dry, gritty, burning eyes, red with irritation as the day goes on or while on digital devices could have anything but dry eye,” Paul M. Karpecki, OD, FAAO, a dry eye expert with Kentucky Eye Institute and Gaddie Eye Centers, said in an interview with Primary Care Optometry News.
As a result of the work by Jeffrey P. Krall, OD, a private practitioner at Krall Eye Clinic in Mitchell, S.D., many optometrists now understand that patients can suffer from misalignment and convergence insufficiency (CI) while experiencing headache and symptoms mirroring those of dry eye. The link between neurology and vision as a headache trigger has only been recently discovered.
“The fact is that eye alignment wasn’t one of those things that I would think of,” Karpecki said. “It took the expertise of those in the field to realize that, yes, it is very common for patients to have symptoms that mimic dry eye secondary to binocular misalignment.”
As the number of digital devices have increased tenfold over the past decade, Karpecki said, digital device usage can compound misalignment issues, bringing them to the forefront.
Six years ago Krall called Karpecki and asked if he had any patients with dry eye symptoms who would not respond to traditional treatment. Karpecki said he certainly did and assembled a group of 10 patients with classic dry eye symptoms of dryness, burning and grittiness. Through testing, together they determined that nine had visual misalignment.
Karpecki explained that the group was a random selection of 10 symptomatic patients who were able to visit his office that day, not patients who measured eye misalignment. Interestingly, all had normal osmolarity measurements but classic symptoms mimicking dry eye disease.
“Dr. Krall started with cover testing, and that taught me what to be on the lookout for,” Karpecki said.
The ‘most frustrating cases’ improved
Vance Thompson, MD, professor of ophthalmology at the University of South Dakota and Sanford USD School of Medicine, told PCON some of his most frustrating cases have been patients with severe dryness and eye strain who did not measure as having dry eye.
“They would come in with a pair of glasses fit by Krall containing the progressive prism, NeuroLens (eyeBrain Medical), and with these glasses their dry eye symptoms diminished,” Thompson said.
Thompson said Krall explained to him how central and peripheral vision work together. If they are not aligned, the brain must work in overdrive, compensating to bring the images together. This added proprioception stimulates the trigeminal nerve, which creates a spectrum of symptoms from dry eye to digital vision syndrome to headaches – some of the worst that neurologists see, he said.
Thompson, who has completed 55 FDA-monitored trials on laser and implant surgery, was struck by the fact that through treating this misalignment and nullifying or eliminating this stimulation of the trigeminal nerve, optometry holds the keys to treating digital vision syndrome, phantom dry eye symptoms and an important class of headaches.
Sharing an analogy, Krall said the trigeminal nerve for visual misalignment is similar to a heart attack sufferer’s left arm pain. There is nothing wrong with the patient’s left arm, but it is a symptom of the heart attack and a result of referred pain. Once the misalignment is corrected, the trigeminal nerve is not triggered, which alleviates the dry eye-like symptoms.
Proprioception, misalignment, headaches
The oculomotor proprioceptive system differs from CI by providing subconscious feedback to the visual system regarding where an object is in space, according to Gary M. Lovcik, OD, a private practitioner at Anaheim Hills Optometric Center.
“However, our eyes do not mediate conscious eye position,” Krall said in a previous article in Primary Care Optometry News. “When our eyes have misjudged the distance of an object from us, cortical supervision is required to adjust this retinal disparity. Without correction, many people will develop headaches and associated asthenopia.”
Another misalignment of the visual system, CI, is one of the most common binocular vision disorders and has been reported to have a prevalence of between 2.5% and 25%, according to research from Yi Pang, PhD, OD, FAAO, and colleagues.
“CI presents with symptoms such as loss of reading placement, reading difficulties, concentration issues, double vision and eye strain,” Lovcik told PCON. “Proprioceptive difficulties can lead to neck tension, headache (chronic and many times severe), eye fatigue, dry eyes, light sensitivity and motion sickness. These symptoms tend to align with digital vision syndrome.
“The Vision Council estimates that 65% of the population has some form of digital vision syndrome,” he continued. “A new innovative technology has been created to help substantially relieve or eliminate symptoms of both CI and proprioception issues.”
Krall and eyeBrain developed the SightSync device for measuring ocular misalignment. Traditional binocular vision tests fail to offer an objective, repeatable alignment screening at all distances, according to a product video from eyeBrain. The SightSync device works by isolating peripheral and central vision to provide a thorough assessment of a patients’ total binocular vision and measuring the amount of compensation at near and optical infinity.
NeuroLens technology incorporates a patient’s individual compensation curve, and the progressive prism reduces or eliminates binocular misalignment at all viewing distances, near and far.
Traditional prism lenses change the alignment of the eye the same amount at distance and near. With NeuroLens, Krall and his team have designed a progressive prism lens that compensates for the differences in alignment that exist when we change fixation from distance to near.
“This has been the best way that I have found to alleviate these symptoms without giving people two pairs of glasses,” Krall said.
Helping patients, growing practice
Lovcik said he generally prescribes between 20 and 35 NeuroLenses a month for conditions such as computer vision syndrome, headaches and migraines.
“It has helped my patients, my practice and myself. I’ve been in the industry for over 30 years and it’s really rejuvenated my passion and joy for eye care,” Lovcik told PCON.
“Imagine patients that have horrific headaches three to four times per week, and you literally wipe these symptoms off the planet,” he continued. “That’s the joy we have now, to dismiss this huge problem that the medical community doesn’t have a solution for. It’s been fun to see so many patients experience lifestyle changes.”
Lovcik completes about 200 exams per month and will usually present NeuroLens to 40 to 70 patients, with a one-out-of-two capture rate. For those patients who choose not to buy NeuroLens, it is typically a cost issue, he said. Many patients tell him they will save the money to purchase the lenses, and they do, in fact, return to purchase them because they see the value in the product.
Lovcik pretests every patient with the lenses and was surprised by how quickly they relieve pain and discomfort.
“The patient will actually feel the results as they sit in my chair,” he said. “They are surprised; they can’t believe we are making that type of difference right off the bat.
“We’ve been educated to think neck issues are ergonomic or a built-in issue with computers, and patients don’t think it’s related to their vision,” he continued. “They are nonbelievers at first.”
Lovcik’s referral rate has also improved immensely. He said he now sees four or five new patients daily versus one new patient per day before implementing the system.
Lovcik noted that NeuroLenses can also neutralize the symptomatology of CI.
“I have offered vision training at Marshall Ketchum University vs. NeuroLenses,” he said. “Patients are opting for NeuroLenses for the efficiency of the technology, as it means immediate yet long-term relief of symptoms without putting in the time of vision therapy.”
Krall commented that he is in favor of vision therapy for a clear-cut case of CI.
“However, the reality is often we assume patients’ symptoms are related to CI when they are a result of the imbalance between how their central and peripheral vision coordinate binocularity,” he said.
Relief for chronic headaches
Krall said the learning process has been enlightening. He has spent the last 4 years gathering data from neurology clinics and working with chronic headache patients.
“These patients have tried every medicine and every injection in the book to alleviate their pain. About 50% of them cease to suffer from headaches,” he said.
The headache pain often resides in the back of the head and is related to how the patient’s brain is measuring the images and where their eyes need to be, he explained.
“We have found a way to measure the misalignment and fit patients with NeuroLenses to alleviate their symptoms,” Krall said. “In the past, I don’t think we have equated these symptoms to the cause for some reason.”
Misalignment has been overlooked, and practitioners were not paying as much attention to it as the condition necessitated, he said.
“No one ever talked to me about this,” Lovcik added. “I looked at headaches as ‘untouchable’ over time. No one explained that solving these issues was possible.”
“We’ve never had a product that can solve the problem,” Krall said. “With typical prisms, in one visual location your sight might be out of sync (at near) and in alignment at distance. We’ve never had a product to solve misalignment in both areas like this.”
“We’ve thought about clarity of vision, but not comfort of vision,” Thompson said. “I think how well eyes are aligning will be part of every exam in the future.
“For optometrists who have incorporated NeuroLens and SightSync technology into their practices,” Thompson added, “the technology has had the biggest impact that I’ve seen in a decade. This is going to be a big deal, and I’m very excited about it.” – by Abigail Sutton
- Pang Y, et al. Clin Exp Optom. 2012;95:192-197.
- Vision Council. Digital Eye Strain Report 2016. www.thevisioncouncil.org/sites/default/files/2416_VC_2016EyeStrain_Report_WEB.pdf. Posted January 6, 2016. Accessed September 27, 2016.
- For more information:
- Paul M. Karpecki, OD, FAAO, is a private practitioner at Kentucky Eye Institute in Lexington and Gaddie Eye Centers in Louisville. He can be reached at email@example.com.
- Jeffrey P. Krall, OD, is a private practitioner at Krall Eye Clinic in Mitchell, S.D. He can be reached at firstname.lastname@example.org.
- Gary M. Lovcik, OD, is a private practitioner at Anaheim Hills Optometric Center in California. He can be reached at email@example.com.
- Vance Thompson, MD, is the founder of Vance Thompson Vision in Sioux Falls, S.D., and serves as a professor of ophthalmology at the Sanford USD School of Medicine. He can be reached at firstname.lastname@example.org.
Disclosures: Karpecki, Krall, Lovcik and Thompson are consultants to eyeBrain Medical.