Prefilled syringes and usability of ophthalmic viscosurgical devices

Takuya Shiba, Hiroshi TsuneokaDepartment of Ophthalmology, Jikei University School of Medicine, Tokyo, JapanPurpose: To examine the influence of the configuration of prefilled syringes on the usability of ophthalmic viscosurgical devices (OVDs).Setting: Department of Ophthalmology, Jikei University School of Medicine, Tokyo, Japan.Design: Experimental study.Methods: The maximum force needed to extrude the whole OVD (extrusion force) was compared among viscous cohesive OVDs (OPEGAN Hi® 0.85 mL and Healon® 0.85 mL) and very low viscosity dispersive OVDs (OPEGAN® 0.6 mL and OPEGAN® 1.1 mL). Additionally, to exclude the influence of any differences between syringes of viscous cohesive OVDs on the extrusion force, empty syringes of the same configuration were refilled with the same products. In addition, the syringe inner surface and that of the piston attached to the tip of the plunger were measured.Results: The extrusion force of Healon 0.85 mL (3.28±0.19 kgf) was significantly (P