A Novel Approach for Suprachoroidal Space Injection: An Experimental Evaluation.

Purpose: This study aims to describe an innovative suprachoroidal space injection technique using a combination of 30 G and 22 G needles attached to a 1 ml injector. The efficacy and applicability of this technique in suprachoroidal injections are evaluated.

Methods: In this study, we conducted both in vitro and in vivo injection experiments using isolated porcine eyes and live SD rats, respectively. The injector needle was inserted into the sclera with the bevelled tip facing the sclera and parallel to the corneal limbus, and the methylene blue solution was injected into the suprachoroidal space. The accuracy of the injection was confirmed by OCT imaging and frozen section microscopy, demonstrating that the dye was successfully delivered to the suprachoroidal space.

Results: The suprachoroidal injector successfully injected the solution into the suprachoroidal space of isolated porcine eyes and live rats without entering the vitreous cavity.

Conclusion: The 22 G needle demonstrated sufficient rigidity and stability to ensure proper scleral compression, supporting the consistency of the injection depth. The 30 G needle exhibited exceptional sharpness and precision, allowing for more accurate control of the drug dosage. The appropriate force applied to the sclera facilitated the precise depth of injection. The angle of the needle, parallel to the corneal limbus, helped avoid penetration into the vitreous or subretinal space, reducing the risk of complications. This device offers new tools and methods for ophthalmic research and clinical practice, with significant clinical application prospects.