Use of 3D printing technology in fabricating intraoperative OCT compatible ophthalmic tools

Abstract

Purpose : To investigate the utility of 3D printers in fabricating intraoperative OCT (iOCT) compatible tools that provide adequate visualization and minimal shadowing of underlying tissues.

Methods : To address iOCT shadowing caused by conventional metallic tools, we 3D-printed a regular ophthalmic forceps and a surgical pick with a shaft diameter of 0.75 mm and a tip diameter of 0.4 mm using semitransparent polycarbonate material. To study the effect of changing the surface texture on tool visualization on iOCT, we designed the top surface of the pick to be either smooth, studded with 0.4 mm hemispheres or squares. For comparison, a metallic forceps and pick were also imaged. In cadaveric porcine eyes, we used Duke intraoperative swept source microscope integrated OCT to image surgical maneuvers such as placing the tip of the forceps and pick in contact with the lens capsule and retina respectively. Each image was graded as poor, moderate, or excellent for visualization of tool, tissue underlying the tool, and surface pattern of the pick on 3 OCT views: en face, B-scan, and 3D.

Results : The 3D printed forceps showed moderate visualization under iOCT with moderate visualization of the underlying lens capsule and iris compared to the metallic forceps which blocked the underlying tissues completely (Fig.1). The tip of the 3D printed pick showed excellent visualization under iOCT (Fig.2). Also, shadowing of underlying retina was significantly reduced with the tested pick compared with the metallic one which completely blocked the underlying retina (Fig.2). Visualization of the surface micropattern was also feasible (Fig.2), but did not show superior advantage over the smooth surface.

Conclusions : We 3D-printed custom surgical tools made of semitransparent material with excellent/moderate visualization and minimal shadowing on iOCT. We also demonstrated the use of 3D printers in fabricating different designs of tools with variable sizes and surface texture. Further research is needed for fine tuning of this technology for more complicated tools.

This is an abstract that was submitted for the 2018 ARVO Annual Meeting, held in Honolulu, Hawaii, April 29 - May 3, 2018.

 

Fig.1: A) 3D printed forceps. B) 3D printed forceps (*) interacting with lens capsule. C) Metallic forceps (*) with complete shadowing of underlying tissues.

 

Fig.2: Top row: 3D printed pick with surface hemispheres (arrows) with excellent visualization of the underlying retina. Bottom row: Metallic pick with complete shadowing of the underlying retina. (*): Tip of the pick.