Visual Processing Dysfunction Diagnosis Commonalities May Inspire Consensus Guidelines

Visual processing dysfunction diagnosis techniques are often common between neuro-ophthalmology experts , according to research presented at the North American Neuro-Ophthalmology Society’s 2023 Annual Meeting held in Orlando, Florida from March 11-16, 2023. “These results can serve as the basis for development of consensus guidelines,”, according to the presenters.

The commonalities include identifying a history of specific higher order visual symptoms and using examination techniques such as interpretation of complex images and reading among patients with higher order visual processing dysfunction.

“Low vision can impede diagnosis of higher order visual dysfunction,” according to the presentation. “Barriers include attributing visual symptoms to ophthalmic disease and lack of standard visual processing tests.”

In this quality improvement/evaluation study, researchers Charissa H. Tan, BS, and Heather E. Moss MD, PhD, identified expert neuro-ophthalmologists in clinical manifestations of higher order visual processing through authorship of relevant journal articles, searching the Neuro-Ophthalmology Virtual Education Library databases for presentations on topics that include the term “neurodegenerative,” and American Academy of Neurology courses. They invited those who currently practice neurology, ophthalmology, or neuro-ophthalmology to participate in a 45-minute video conference semi-structured interview concerning how the experts clinically evaluate visual processing in patients with and without visual impairment. The researchers transcribed and coded the interviews for themes. 

Between May 2022 and June 2022, 12 of the 52 invited experts participated in the study. All participants were practicing neuro-ophthalmologists, 66% were neurology trained, 3 to 34 years in clinical practice, 20% to 80% of time was spent in clinical care, and 10 to 80 patients were seen per week. 

The researchers found that common themes for history features were specific higher order visual symptoms (9/12) and associated non-visual cognitive symptoms (7/12). They found that common examination techniques were interpretation of complex images, specifically cookie theft or Navon (9/12), and reading (12/12). They found that 8/12 experts make modifications for visual impairment starting at visual acuity ranging from 20/50 to count fingers. 

“Experts in higher order visual processing dysfunction utilize common approaches for diagnosis of visual processing dysfunction in the setting of ophthalmic disease,” according to the presenters.

This study was limited by the small sample size of experts.