OCT angiography effective for managing neurodegenerative disorders, but challenges remain

Optical coherence tomography angiography can play “a pivotal role” in managing neurodegenerative disorders, though larger studies are needed to optimize its use for this purpose, according to findings published in Eye and Brain.

“Optical Coherence Tomography Angiography (OCT-A) is a recently introduced imaging modality which is used mainly for the assessment of the integrity of the retinal vasculature in a wide range of retinal vascular diseases,” the researchers wrote. “Given all the ... significant advantages of OCT-A, its use has been gaining increasing popularity among the medical retina specialists. At the same time, there is a lot of debate as to whether OCT-A could also be used in neuro-ophthalmology and neurology.”

Georgios Tsokolas, MD, MSc, of the ophthalmology department at Leicester Royal Infirmary in Leicester, England, and colleagued performed a literature review on the use of OCT-A in neurological and neuro-ophthalmological conditions from 2015, the year the imaging modality received FDA approval, through May 2020. In total, they evaluated 123 manuscripts.

The review demonstrated that OCT-A has been used so far to describe abnormalities in multiple sclerosis, Alzheimer’s disease, arteritic and non-arteritic optic neuropathy, Leber’s hereditary optic neuropathy papilloedema, Parkinson’s disease, Huntington’s disease, amyotrophic lateral sclerosis, Wolfram syndrome, migraines, lesions of the visual pathway and cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy.

The researchers found that OCT-A “can play a pivotal role” in detecting and monitoring a wide range of neurodegenerative disorders. The imaging tool provides clinicians with data about structural changes in the retinal and optic nerve vascular networks, according to Tsokolas and colleagues. That information could be used to identify biomarkers that would enable clinicians to monitor disease progression and to develop potential treatments aimed at halting or reversing the progression of currently incurable diseases.

However, the researchers also noted that there are “many shortcomings” that prohibit more widespread use of OCT-A for such purposes. For example, many neurodegenerative disorders affect mental capacity, according to Tsokolas and colleagues; as a result, suboptimal cooperation during the capture of OCT-A could result in poor-quality images “that can lead to inaccurate interpretation due to motion artifacts.” In addition, the presence of comorbidities in patients who are elderly that also cause retinal changes could make it “quite challenging to describe accurately the real extent of the contributions of each pathological entity due to substandard segmentation carried out by the current OCT-A software available,” the researchers wrote.

Additional research is needed to “eliminate the aforementioned limitations,” according to Tsokolas and colleagues.