Abstract
Purpose :
Following corneal trauma, recurrent corneal erosions (RCE) occur in up to 18% of patients, resulting in episodic pain, photophobia, and healing episodes. Anterior stromal puncture (ASP), commonly used to treat RCE, uses a small gauge needle to induce scarring in the anterior corneal stroma. This technique creates visible corneal scars, therefore, ASP cannot be performed in the central visual axis, where most RCEs occur. We have designed and tested a novel instrument for ASP that can create hundreds of microscopic imprints with defined, limited penetration into the cornea to enhance epithelial cell adherence without corneal scarring. The objectives of these studies were to prototype and validate the clinical efficacy of this novel medical device to establish a new therapeutic paradigm for the treatment of RCEs.
Methods :
Preclinical studies were performed in small animal models of corneal abrasion in IACUC-approved studies. Pilot human data was obtained in an IRB-approved human subject pilot clinical trial. We validated the performance of alternatively fabricated “plexitome” arrays in corneal tissue to determine tissue penetration of varying designs (aspect ratio, density, length) by mechanical testing methods. Healing of epithelial injuries and regeneration following treatment in animal models and human subjects was quantified by fluorescence staining and quantitiative image analysis. Histologic analysis was performed on animal tissues.
Results :
Imprinting was seen clinically and enhanced re-epithelialization of denuded corneal stroma in animal and human subjects. Histology showed focal subepithelial scarring at the site of imprinting without stromal scarring. This outcome was confirmed in human clinical studies. One patient with a history of multiple RCEs was disease free for more than one year after imprinting. Rapid healing of acute abrasions in rodent models limited the evidence of clinical efficacy of the device in the acute injury model.
Conclusions :
Microimprinting of the cornea in RCEs and corneal abrasions appears to enhance wound healing in animal models and human studies and does not cause corneal scarring. Thus, it may be a novel and effective way of enhancing the healing of corneal abrasions and treating RCEs in the optical axis.
This abstract was presented at the 2019 ARVO Annual Meeting, held in Vancouver, Canada, April 28 - May 2, 2019.