The Durette® ocular implant, made of clear acrylic material (PMMA), is a smooth-surface motility implant used for enucleation, evisceration, and secondary implantation. There are two 20 mm diameter models that are quasi-spherical: Model I, which has a slightly flattened smooth anterior surface (1 mm flatter vs. a sphere); and Model IV, which has four pronounced mounds (within the sphere) for optimal coupling and motility. The implants have a network of 20 interconnected tunnels (1 to 2 mm) offering the eye surgeon with 3 levels for suturing each rectus muscle, and allowing new tissue to form and integrate with surrounding tissue, while aiming to prevent migration, forward displacement and tissue stretching. They both have an off-center medial posterior elongation for added volume and better front positioning of details for coupling with ocular prostheses.
An implantable ocular device designed to permanently fill the orbital cavity following enucleation, evisceration, or after the removal of another ocular implant (used as a secondary implant), to replace the volume and possibly, given the surgical method, to impart motion to the eventual ocular prosthesis (the artificial eyeball). It is typically aspherical and may have porous surfaces to facilitate colonization by fibrovascular tissue to offer the advantages of reduced risk of infection or implant extrusion. It is available in various sizes and is typically made of polymethylmethacrylate (PMMA), poly 2-hydroxyethylmethacrylate (PHEMA), or silicone.