Abstract
The efficacy of two novel artificial vitreous body substitutes (VBS) consisting of highly biocompatible thiolated cross-linked hyaluronic acid (HA)-based hydrogels in comparison to silicone oil in a model of retinal detachment was investigated. Pars plana vitrectomy (23G) was performed in the right eye of 24 pigmented rabbits. Retinal detachment of two quadrants was induced by creating a small retinotomy near the vascular arcade and injecting balanced salt solution (BSS) subretinally. The retina was reattached by injecting air, which was followed by increasing the infusion pressure, and the retinal tear was treated by endolaser photocoagulation. At the end of the procedure, the eye was filled either with 5000-cs silicone oil (after fluid air exchange) or the respective hydrogel (with two different viscosities). Follow-up examination included slit lamp examination, funduscopy, intraocular pressure measurements (IOP), optical coherence tomography (OCT) and electroretinogram (ERG) measurements. After a maximum follow-up of four weeks both eyes were removed, examined macroscopically, photographed, and prepared for histology. Of the eight rabbits that received silicone oil, seven (87.5%) developed a recurrent retinal detachment with pronounced proliferative vitreoretinopathy within the first two weeks after surgery. In contrast, in the hydrogel treated eyes, the retina stayed attached in the majority of the cases (73.3%). IOP and retinal morphology were normal as long as the retina remained re-attached. In conclusions, this model of retinal detachment, both thiolated crosslinked hyaluronate hydrogels showed superior efficacy when compared to silicone oil. These hydrogels have a promising potential as novel vitreous body substitutes.
Highlights
Vitreous substitutes such as silicone oils or gas tamponades are used to stabilize and reattach complicated cases of retinal detachment.[1]
Prior to their surgical use, the generated hydrogels were characterized with respect to optical and rheological properties and two tVBS hydrogels with differing viscosities were chosen for further evaluation
Rheological analysis with hydrogel pre-sheared by ejection from a 5 mL syringe through a 20-gauge needle resulted for vitreous body substitutes (VBS) soft in a storage modulus (G’; ω = 1 1/s) of 150400 mPa and a loss modulus (G”; ω = 1 1/s) of 4693 mPa
Summary
Vitreous substitutes (endotamponades) such as silicone oils or gas tamponades are used to stabilize and reattach complicated cases of retinal detachment.[1]. Potential alternatives to current VBS may be compounds that are hydrophilic, transparent, with a refractive index close to 1.33, and stable over a longer time It may be advantageous if these substances show a higher viscosity and elasticity than the human vitreous body. The goal of this study was to evaluate the efficacy of a vitreous substitute based on tVBS in a model of retinal detachment in comparison to current standard treatment with silicone oil. Prior to their surgical use, the generated hydrogels were characterized with respect to optical and rheological properties and two tVBS hydrogels with differing viscosities were chosen for further evaluation
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
