In Vivo Confocal Microscopy Demonstrates Intranasal Neurostimulation-Induced Goblet Cell Alterations in Patients with Dry Eye Disease

Abstract

Purpose : Goblet cells (GCs), found in the conjunctival epithelium, are specialized mucin secreting cells that contribute to maintenance of tear film stability and ocular surface lubrication. The Intranasal Tear Neurostimulator (ITN) delivers a small electrical current to sensory neurons of the nasal cavity that stimulate the nasolacrimal reflex and induce tear production. This study compared morphological GC changes before and after use of the ITN by means of laser in vivo corneal confocal microscopy (IVCM).

Methods : This was a single center, single-arm, study that included 15 dry eye subjects (22 eyes). Laser IVCM images were taken before and after approximately three minutes of ITN application at the inferonasal area of the bulbar conjunctiva. GC were analyzed and measured by ImageJ™ software. Three images from each patient were selected according to their quality and accuracy to be further analyzed by two masked observers. GCs were selected according to the following criteria: 50<area<150 mm², round or oval shaped, highlighted from the background, well defined borders. All data are shown as mean±SD. Mean data were compared using a paired t-test. P values <0.05 were considered statistically.

Results : Morphological analysis was performed for a total of 755 GCs pre- and 712 GCs post-application of the ITN. Mean pre- and post-GC areas were 67.52±40.03mm² and 58.72±31.16mm², respectively. The mean change in area, 8.8±8.8 µm, representing a 13.03% reduction following use of the ITN, was statistically significant (p<0.001). Mean pre- and post-stimulation GC perimeters were 48.78±21.84mm and 42.79±19.25µm, respectively. The mean change in perimeter, 5.99±2.59µm, representing a 12.27% reduction following use of the ITN, was statistically significant (p<0.001).

Conclusions : The ITN significantly reduced GCs area and perimeter within three minutes of stimulation, demonstrating a direct effect on GCs. Laser IVCM is a reliable tool to assess morphological GC changes.

This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.