Customized 3D printing: A novel approach to migrated orbital implant

Abstract

This paper describes a novel approach to treat migrated orbital implants post socket surgery. Implant migration may hinder the final aesthetic outcome of a custom ocular prosthesis. Once an implant migrates within the orbit there tends to be fibrosis around the implant. This fibrosis does not allow for centeration of the implant during repeat surgery. Hence treatment of a migrated implant traditionally involves implant removal with dermis fat grafting. Dermis fat graft though an option, needs a second site surgery that may be unacceptable to many patients. Also the rate of graft necrosis is as high as 40%. This paper describes a technique to create a custom orbital implant that allows recenteration of the migrated implant centrally, using 3-dimension (3D) printing and rapid prototyping to construct the patients affected orbit. This orbit is used as a mould to create the custom orbital implant that aids in volume augmentation as well as recenteration of the migrated orbital implant.

Keywords: 3D printing; Computer assisted; Custom designed; Migration; Orbital implant; Patient specific implants; Secondary implant.

Fig. 1

Pre-operative examination details. A: right decentered prosthesis with superior sulcus deformity, B: inferotemporal migration of implant highlighted with ^* and shelving of the lower fornix, C: Inferior edge of the prosthesis resting on the lower eyelid margin with increased inferior scleral show, D: CT orbit in the coronal plane showing inferotemoral spherical orbital implant migration.

Fig. 2

Skull models in soft copy and 3D. A: skull model built in 3D using DICOM images of the patients CT orbit, B: skull model printed in plastic and used as a mould to fabricate an orbital implant from PMMA.

Fig. 3

Comparison of pre and post-operative result. A: pre-operative standard view photograph of the patient with superior sulcus deformity and decentered ocular prosthesis, B: post-operative standard view photograph of the patient with correction of the superior sulcus deformity and a better fitting ocular prosthesis. C: post-operative CT orbit of the patient showing an inferotemoral implant pushing the spherical implant towards the central intraconal space. D: post-operative birds view showing adequate orbital volume correction with both the implants in place.