Scleral Implants Research Articles

Intrusion of Scleral Implant Associated with Conjunctival Epithelial Ingrowth

A 26-year-old boxer sustained a rhegmatogenous retinal detachment that was repaired successfully. Repeated blunt trauma caused a second retinal detachment two years later. Three attempts at repair by scleral buckling with diathermy and drainage of subretinal fluid were unsuccessful, and the eye was enucleated. Pathologic examination showed internal erosion of the intrascleral silicone implant into the vitreous compartment. Conjunctival-like epithelium lined the intrascleral bed of the implant and extended through the internal erosion onto intraocular structures, and this conjunctival epithelium was traced onto the external surface of the eye. Repeated dissection and applications of diathermy, combined with drainage of subretinal fluid, had weakened the sclera so that the silicone implant eroded internally and epithelium grew into the eye.

Effects of scleral collagen upon the healing of experimental osseous wounds.

Standardized wounds were created in the femurs of 13 female white New Zealand rabbits and implanted with autogenous scleral connective tissue, Achilles bovine tendon collagen chips and cores of cancellous autogenous bone and marrow. A blood-filed wound served as a control. The dynamics of the healing of these wounds over periods of time ranging from 12 days to 3 months was studied by routine histology, fluorescent microscopy and by radiography. Rapid healing of the control and bone implant wounds occurred but was retarded by the implantation of sclera. Collagen chips provoked an active lymphocytic response and severely impeded the healing of the experimental wounds. These experiments were discussed in light of the current interest in allogenic scleral implants in periodontal therapy.

Infections following scleral buckling procedures.

Cultures of 638 routine preoperative conjunctival specimens prior to retinal detachment surgery demonstrated bacterial contamination with<i>Staphylococcus epidermidis</i>in 37%, S<i>aureus</i>in 3%,<i>Proteus</i>in 1%,<i>Klebsiella</i>in 1%, and<i>Pseudomonas</i>in 0.2%. Postoperative infection with rejection of the scleral implants occurred in 4% (37) of 878 operations. The risk of a clinical infection was increased statistically when a preoperative culture demonstrated pathogenic bacteria, when episcleral solid silicone was used in surgery, and when the procedure was a reoperation. Age, sex, side of surgery, type of anesthesia, aphakia, preoperative contamination with<i>S epidermidis</i>, drainage of subretinal fluid, disinsertion of muscles, or the use of silicone sponges did not influence the vulnerability of the eyes to postoperative infections. The risk of recurrent detachment following surgical removal of the infected materials was found to be 33%.

The changing character of the infected scleral implant.

In a previous report a syndrome of scleral abscess in the presence of diathermy was described. Unless the implant was removed, perforation might occur. Animal models suggested that the substitution of cryopexy would prevent perforation. This proposition has now been tested in 800 detachment patients. The incidence of postoperative infection continues to be 3%, but the character of the infection with cryosurgery has changed from an abscess with intraocular signs to that of an extraocular granuloma. The treatment is removal of the implant, but there is no urgency because perforation does not occur.

Scleral marker for retinal detachment surgery.

The use of extreme cold in lieu of diathermy application to the scleral surface in retinal detachment surgery has required several modifications in technique. Surface localization of a retinal hole was conveniently accomplished by placing one or more diathermy applications to the scleral surface overlying the hole while visualizing the fundus with indirect ophthalmoscopy. The diathermy usually produced small visible scleral lesions which were necessary for the proper placement of scleral implants or encircling elements. Since cold application to the scleral surface usually leaves no visible lesion, the need for a suitable scleral marker arose. Figure 1 depicts an instrument which has proved of value. It is patterned after the thimble-type scleral depressor now widely used in this country. A piece of hollow, stainless steel tubing, 1½ mm in diameter and about 1 mm in length, is welded to the tip of the instrument after the removal of the crossbar.

Modified Burch Type Evisceration with Scleral Implant

Modified Burch Type Evisceration with Scleral Implant

Modification and defence of the scleral implant.

Modification and defence of the scleral implant.

Evisceration of the Globe with Scleral Implant and Preservation of the Cornea

Evisceration of the Globe with Scleral Implant and Preservation of the Cornea