MSOR5  Presentation Time: 5:05 PM: A Novel 3D Printing Method for an Eye Plaque “Dummy” for Ocular Melanoma Brachytherapy

Purpose Suture placement by the ocular oncology surgeon is a necessary critical step prior to insertion of a radioactive plaque for ocular melanoma brachytherapy. This step relies on placement of a “dummy” plaque with the exact dimensions of the radioactive plaque. The purpose of this project is to create a custom dummy plaque applicator for the 22 mm notched gold plaque using in-house 3D printing. Materials & Methods Using SolidWorks 2022 (Dassault Systèmes, Waltham, MA), a computer-aided design (CAD) file was created replicating a heavily used gold plaque which no longer has a usable dummy plaque for use in pre-insertion placement verification. The file was exported as a 3D file (surface tessellation language, STL) and prepared for 3D printing using Formlabs’ Preform print preparation software (version 3.25.1). The 3D printed dummies were oriented on the printer to have no cups or supports on the side edges that would come in contact with the patient's external sclera. Density of supports was set to 0.5, touchpoint size was set to 0.30 mm and no internal supports and layer thickness parameter was set to 0.05 mm. The dummies were printed in FormLabs BioMed Clear V1 on a Formlabs Form-3 3D printer (www.formlabs.com). Post printing, the dummies were then processed in isopropyl alcohol, cured, and finished according to manufacturer instructions. To improve the dummies’ transparency, they were polished utilizing a rotary tool. Chemical and sterilization cycle tests were performed to ensure dummy integrity. Results Four dummy plaques were printed. Using digital calipers, the 3D printed dummy dimensions were verified to be within 0.5mm of the notched plaque. The polishing process created acceptable light opacity for the eye plaque procedure in the OR for the first few cases tested. No impactful discoloration or material change was observed during the chemical and sterilization cycle tests performed. Conclusions 3D printing can be utilized to produce custom eye plaque dummies using transparent biocompatible materials that are chemically inert and suitable for human use. This capability introduces an additional layer of patient-specific hygienics. Suture placement by the ocular oncology surgeon is a necessary critical step prior to insertion of a radioactive plaque for ocular melanoma brachytherapy. This step relies on placement of a “dummy” plaque with the exact dimensions of the radioactive plaque. The purpose of this project is to create a custom dummy plaque applicator for the 22 mm notched gold plaque using in-house 3D printing. Using SolidWorks 2022 (Dassault Systèmes, Waltham, MA), a computer-aided design (CAD) file was created replicating a heavily used gold plaque which no longer has a usable dummy plaque for use in pre-insertion placement verification. The file was exported as a 3D file (surface tessellation language, STL) and prepared for 3D printing using Formlabs’ Preform print preparation software (version 3.25.1). The 3D printed dummies were oriented on the printer to have no cups or supports on the side edges that would come in contact with the patient's external sclera. Density of supports was set to 0.5, touchpoint size was set to 0.30 mm and no internal supports and layer thickness parameter was set to 0.05 mm. The dummies were printed in FormLabs BioMed Clear V1 on a Formlabs Form-3 3D printer (www.formlabs.com). Post printing, the dummies were then processed in isopropyl alcohol, cured, and finished according to manufacturer instructions. To improve the dummies’ transparency, they were polished utilizing a rotary tool. Chemical and sterilization cycle tests were performed to ensure dummy integrity. Four dummy plaques were printed. Using digital calipers, the 3D printed dummy dimensions were verified to be within 0.5mm of the notched plaque. The polishing process created acceptable light opacity for the eye plaque procedure in the OR for the first few cases tested. No impactful discoloration or material change was observed during the chemical and sterilization cycle tests performed. 3D printing can be utilized to produce custom eye plaque dummies using transparent biocompatible materials that are chemically inert and suitable for human use. This capability introduces an additional layer of patient-specific hygienics.