Intranasal tear stimulating device may offer a drug-free remedy for dry eye

Researchers have developed a new, hand-held intranasal tear neurostimulator (ITN) device to increase tear production, and deliver significant relief for patients with dry eye, according to research presented in New Orleans, LA, at AAO 2017, the 121st Annual Meeting of the American Academy of Ophthalmology, in early November.

The INT—called TrueTear—was developed by Michael Ackermann, a biomedical engineer from Stanford Biodesign, Stanford, CA. Ackermann and colleagues found that the use of the ITN significantly increased tear volume, with no changes in either total lipid or total protein concentrations. They concluded that ITN stimulation may provide more than just diluted aqueous tears.

With this new technology, dry eye sufferers may have a new, drug-free alternative to lubricating eye drops and topical ointments. The INT produces a complete tear, comprised of all the elements present in natural tears. Patients insert the INT into the nose, and it stimulates the lacrimal glands to release tears, producing much the same reaction as cutting an onion.

Researchers at the Cincinnati Eye Institute, Cincinnati, OH, undertook this single-arm study in 97 patients with dry eye to quantify the concentrations of total lipids and total proteins in tears after acute use of the ITN. They conducted the following assessments both pre- and post-ITN use:

• Tear volume: tear meniscus height (TMH) with optical coherence tomography (OCT)
• Total lipid concentration via modified spectrophotometric sulfo-phospho-vanillin reaction
• Total protein concentrations via micro-bicinchoninic acid protein assay

After stimulation, mean TMH was significantly higher than before (634.9 vs 238.4 µm, respectively; P < 0.001). Researchers found no differences between pre- and post-stimulation total lipid levels (0.391 vs 0.364 µg/µL) or in total protein concentrations (12.6 vs 11.8 µg/µL).

For the more than 20 million Americans who suffer from dry eye, the INT would be a welcome respite from the artificial tears most of them use to relieve symptoms. Another advantage to the INT is that the tears are natural tears, containing the necessary and inherent mixture of oils, water, proteins, and mucus necessary for proper lubrication and protection of the eyes.

“I believe this will be a very beneficial treatment option for our dry eye patients,” said lead researcher, Edward J. Holland, MD, director of Cornea Services, Cincinnati Eye Institute, and professor of clinical ophthalmology at the University of Cincinnati. “It’s an innovative technology that effectively and safely increases tear production.”