Novel Visible-Light Curable Hydrogel for Closure of Sclerotomy Wounds in Pars Plana Vitrectomy

Abstract

Purpose : Current approaches to close sclerotomy wounds following pars plana vitrectomy (PPV), including (1) no-closure, (2) suturing, and (3) application of fibrin glue sealants (FG) are at risk for hypotony and endophthalmitis, potentially time-consuming to perform and uncomfortable for patients, and hard to prepare and apply, respectively. In this study, the efficacy and stability of a novel visible-light curable natural hydrogel (LC-COMatrix) was evaluated for closure of sclerotomy wounds following PPV in ex-vivo models.

Methods : The human corneoscleral tissues with exposed sclera (removed conjunctiva) were mounted on an artificial anterior chamber connected to a pressure pump and a pressure sensor. A sclerotomy wound was created 4-mm from the limbus using a 23g trocar. The created wounds were left unclosed (N=10), closed with FG (N=10), or closed with LC-COMatrix (N=10). Afterwards, the pressure was increased (0.2 ml/s) and the burst pressure was recorded. In addition, fresh adult porcine eyeballs underwent a 2-port 23g PPV with vitreous removal and replacement with saline. One of the created slcerotomy wounds on each eyeball was closed with LC-COMatrix (N=10) or left unclosed (N=10). The infusion pressure was increased (5 mmHg/s) and closure/failure pressure was recorded. Furthermore, 23g sclerotomy wounds on human scleras (N=12) were closed with LC-COMatrix and the tissues were subjected to rotational shake while incubated in corneal preservation solution. The scleral adhesivity of LC-COMatrix was followed up using anterior segment optical coherence tomography (AS-OCT) and slit lamp biomicroscopy for 30 days.

Results : The average burst pressure for human scleras closed with LC-COMatrix was 220.48 mmHg (range 75.1-400.0), which was significantly higher than those of FG (133.7 mmHg, range 5.0-430.0, p=0.049, and no-closure (20.5 mmHg, range 6.1-75.3, p<0.001). The average burst pressure of porcine eyeballs’ sclerotomy wounds closed with LC-COMatrix was 234.9 mmHg (range 35.2-543.2), while the burst pressure in the control group was 25.4 mmHg (range 6.4-60.0) (p<0.001). Regular examination with slit-lamp and AS-OCT showed that LC-COMatrix was consistently attached to the human scleras during the 30 days of follow-up.

Conclusions : LC-Comatrix is a novel visible-light curable natural and easy-to apply hydrogel with potential application for closure of sclerotomy wounds following pediatric and adult PPVs.

This abstract was presented at the 2022 ARVO Annual Meeting, held in Denver, CO, May 1-4, 2022, and virtually.