Controversies in Enucleation Technique and Implant Selection: Whether to Wrap, Attach Muscles, and Peg?

Abstract

The advent of porous orbital implants has greatly advanced the field of anophthalmic surgery. The development of hydroxyapatite (HA) implants initiated a new generation of porous implants. Porous polyethylene and aluminum oxide are now commonly used alternatives. Orbital implants are available in spherical, mounded, egg, and conical shapes. Implant material selection is determined by several factors, including patient age and medical history, cost, availability, and surgeon preference. A variety of techniques may be utilized to determine the appropriate implant size. Adults undergoing enucleation surgery most frequently require a 20- to 22-mm sphere, whereas 18- to 20-mm spherical implants may be adequate for evisceration procedures. Patients younger than 5 years old typically receive a nonporous implant as this facilitates replacement with a larger porous implant later in childhood or adolescence. Older pediatric patients may do well with porous implants. Appropriate implant size selection depends on the age and development of the patient. Surgeons who use porous polyethylene as their implant of choice commonly do not use an implant-wrapping material. Wrapping HA and aluminum oxide implants facilitates implant insertion and rectus muscle attachment to the implant. Several implant-wrapping materials are commercially available. Polyglactin 910 (Vicryl®) is simple to use, is readily available, and may permit earlier implant fibrovascularization than other available materials. Porous implants can be coupled to the overlying artificial eye with a titanium peg system. These coupling systems may allow for greater prosthesis motility. Implant peg use has declined due to the high incidence of postpegging complications (increased discharge, recurrent pyogenic granulomas, implant exposure around the peg, implant infection, tissue overgrowth, clicking).