Modification of the Scleral Openings to Reduce Tissue Breakdown and Exposure after Hydroxyapatite Implantations

Abstract

We compared the incidence of exposure of the hydroxyapatite implant after evisceration according to the position of scleral windows which allow rapid fibro- vascularization into the implant. Three patients (10%) developed tissue breakdown and exposure of the hydroxyapatite, out of 30 patients who had external scleral windows located in a position just anterior to the insertion of each of the rectus muscles, whereas no patient developed exposure, out of 24 patients who had internal scleral windows located in a position just posterior to the insertion of each of the rectus muscles. Internal windows sealed with rectus muscles could prevent direct contact between implant and the overlying Tenon’s capsule and conjunctiva. These findings seem to indicate that the rough spicular surface of the hydroxyapatite irritates and erodes the overlying Tenon’s capsule and conjunctiva.

Evisceration with four anterior relaxing incisions and circumferential posterior sclerotomies with porous polyethylene orbital implants: an 8-year study

“…In this surgery, it is important to reduce volume loss and, at the same time, decrease tension on the surgical wound. Many techniques have been recommended to achieve these goals: relaxing scleral incisions, posterior sclerotomies, scleral flaps, implant coverage by multiple scleral layers and others (Stephenson 1987; Kostick & Linberg 1995; Lee et al. 1995; Yang et al.…”

“…In this surgery, it is important to reduce volume loss and, at the same time, decrease tension on the surgical wound. Many techniques have been recommended to achieve these goals: relaxing scleral incisions, posterior sclerotomies, scleral flaps, implant coverage by multiple scleral layers and others (Stephenson 1987;Kostick & Linberg 1995;Lee et al 1995;Yang et al 1997;Long et al 2000;Massry & Holds 2001;Choung et al 2005;Madill & Maclean 2005;Sales-Sanz & Sanz-Lopez 2007). Fibrovascular ingrowth in the implant begins at the sclerotomy sites (Shields et al 1991;Sarvananthan et al 1999).…”

Review of Surgical Techniques in Evisceration

“…Different ways in handling the orbital implant have also been attempted. Lee et al 89 described a technique of drilling holes in the hydroxyapatite implant, followed by creating 4 rectangular external scleral windows at a position anterior or posterior to the insertion of the 4 rectus muscles, in order to promote rapid tissue ingrowth into the implant. Scleral quadrisection from the limbus to the optic nerve without optic nerve disinsertion and anterior surface flattening of the hydroxyapatite implant was reported by Yang et al in 1997 90 .…”

Evisceration in the modern age

“…In the same year, Lee et al . reported the creation of scleral windows posterior to each of the rectus muscle insertion 9. In 1997, Jordan and Anderson described disinserting the optic nerve and performing small radial sclerotomies 10.…”