Methodological Approach to Improve Surgical Outcomes of a Pig Subretinal Implantation Model

Area of Science:

• Ophthalmology
• Surgical Innovation
• Retinal Implantation

Background:

• Subretinal implantation surgery is crucial for advanced retinal therapies.
• Maintaining intraocular pressure (IOP) and controlling bleeding during sclerotomy are critical challenges.
• Current techniques can lead to hypotony and retinal prolapse, reducing surgical success.

Purpose of the Study:

• To enhance the success rates of subretinal implantation surgery in a porcine model.
• To identify and mitigate factors negatively impacting surgical outcomes.
• To develop improved surgical techniques and instrumentation for subretinal procedures.

Main Methods:

• Video analysis of 37 subretinal implantation surgeries to identify critical variables.
• Ex vivo experiments to measure intraocular pressure (IOP) changes and test implanter prototypes.
• Development and testing of a modified surgical procedure including choroidal precauterization and a novel inserter tip design.

Main Results:

• Sclerotomy time was prolonged by bleeding and fluid outflow, leading to retinal prolapse in 39.1% of cases.
• Choroidal precauterization reduced uncontrolled bleeding to 0% and improved implantation success from 73% to 90%.
• A modified inserter tip restored IOP to 27.1 ± 1.9 mm Hg, achieving 100% implantation success when combined with precauterization.

Conclusions:

• A modified subretinal implantation procedure, incorporating choroidal precauterization and an optimized inserter, effectively manages bleeding and IOP.
• This approach significantly decreases hypotony and sclerotomy time, thereby improving surgical success rates.
• Optimized management of intraocular pressure and bleeding is essential for advancing implant-based retinal therapies.