Speakers urge clinicians to screen patients for binocular vision dysfunction.
Published June 27, 2014
Read article on Healio.com | Primary Care, Optometry News. Nancy Hemphill, ELS
PHILADELPHIA – Vertical heterophoria and superior oblique palsy can cause a variety of symptoms that, if not diagnosed properly, can lead to unnecessary and ineffective treatments, two clinicians said here at Optometry’s Meeting.
These frequently misdiagnosed binocular vision conditions cause symptoms such as dizziness, nausea, headaches, severe neck and shoulder discomfort, visual problems while driving, anxiety, reading difficulties, sleep problems, diplopia and blurring, according to Debby Feinberg, OD, and Mark S. Rosner, MD.
Feinberg said a “recurring theme” is that the symptoms have been present for a long time, the patient has been seen by many different providers, many tests have been done, many medications have been prescribed and many procedures have been conducted, but the patient is not getting any better.
There have been two roadblocks to diagnosis, Feinberg said.
“Vertical alignment measurements and equipment used to diagnose vertical heterophoria (VH) and superior oblique palsy (SOP) are not sensitive enough,” she said. “They are found only half of the time. We need a more accurate method to diagnose VH and SOP and define the amount of prism needed.”
She said she and colleagues developed the prism challenge technique: adding incremental amounts of prism until symptoms are minimized and visual clarity is maximized.
“Really small amounts of prism did not exist – we had to make them up, as well as additional tools to measure very small units,” Feinberg said.
The second roadblock has been that the constellation of symptoms created by VH and SOP are not being recognized by visual professionals, she said.
“The specific combination of symptoms and frequency are different for every patient,” she said. “One might have more headache, another might have more dizziness, another more anxiety. We had to sort out the symptoms.”
The clinicians developed the Binocular Vision Dysfunction Questionnaire, with one version for adults and another for children.
“It’s become the most powerful and consistent tool to identify this population,” Feinberg said.
Patients are questioned regarding the existence and frequency of about 25 symptoms including pain, dizziness, neck or shoulder discomfort, motion sickness, anxiety, head tilt, double vision, blurred vision and reading difficulties.
Feinberg said typical binocular vision symptoms are found to be “surprisingly infrequently positive.”
When patients have any of the symptoms on the questionnaire, “I can’t stress how important it is to screen your patients,” she said.
Feinberg said after screening patients and treating them with prismatic lenses over the course of 20 years, she has seen a 70% reduction of symptoms within 20 to 30 minutes of prism application.
“That’s just the first day,” she said.
By the second or third visit, an 80% average reduction of symptoms is seen by the end of therapy, usually after 2 to 3 months of using progressive lenses, she said.
Rosner said one benefit of proper diagnosis and treatment of VH and SOP is getting patients off of interfering medications.
He noted that once the initial sequence of visits is finished (two to three visits over 2 to 3 months using a progressive relaxation technique), only biannual treatments are needed to keep up.
“Successful therapy leads to minimized need of further testing/evaluation, expedited improvement with other rehabilitation therapies and return to work,” Rosner said.