e-PTFE as scleral buckling episcleral implants: An experimental and histopathologic study

Abstract

To investigate the effects of focal implantation of expanded polytetrafluoroethylene (e-PTFE) episcleral implants (i.e., explants or exoplants) on surrounding ocular tissues, an experimental and histopathological study was performed. Twenty-seven Fauve de Bourgogne rabbits eyes were implanted for a period of 3-11 months with oval-shaped e-PTFE episcleral implants. A newly formed capsule constantly encased the implants. Affected by the only two severe complications observed, 2 eyes had an endocapsular acute inflammation and could not be included in the study. Finally, 25 eyes were studied histopathologically. Neither intrusion nor extrusion of episcleral implants was observed. Other changes were related to implant characteristics. The inner surface of the capsule was often covered with numerous giant cells attesting to a foreign-body granuloma developed against the irregular outline of the episcleral implants. The porosity of the material was closely related to its surface irregularity, and also allowed its colonization by a fibrovascular and inflammatory tissue mainly in its peripheral layers. Under episcleral implants, sclera was both thinned and invaginated. Expanded PTFE hydrophobia was the other factor that might have suscitated granuloma. These microscopic changes are in contrast with an overall good apparent experimental tolerance to the material. However, additional studies on the long term behavior of this material would be helpful.

Safety Assessment of Polyfluorinated Polymers as Used in Cosmetics

“…To investigate the effects of focal implantation of expanded PTFE episcleral implants (i.e., explants or exoplants) on surrounding ocular tissues, an experimental and histopathological study was performed. 41 PTFE episcleral implants were inserted (for a period of 3–11 mo) into the eyes of 27 Fauve de Bourgogne rabbits. A newly formed capsule constantly encased the implants.…”

Scleral buckling biomaterials and implants for retinal detachment surgery

“…Porous expanded PTFE (e-PTFE), commercially known as Goretex, has been more recently proposed by several authors for scleral buckling procedures [77][78][79][80][81]. Many studies reported the colonization of porous PTFE buckles by fibrocellular tissue, as well as the adhesion to surrounding conjunctival tissue [77][78][79]81]: colonization by fibrovascular tissue can represent an extra-challenge for the surgeon if implant removal is required in the case of re-operation.…”

“…Porous expanded PTFE (e-PTFE), commercially known as Goretex, has been more recently proposed by several authors for scleral buckling procedures [77][78][79][80][81]. Many studies reported the colonization of porous PTFE buckles by fibrocellular tissue, as well as the adhesion to surrounding conjunctival tissue [77][78][79]81]: colonization by fibrovascular tissue can represent an extra-challenge for the surgeon if implant removal is required in the case of re-operation. Adverse or inflammatory responses of tissues to e-PTFE were minimal or very mild [77][78][79][80]: the material was generally well-tolerated, thereby demonstrating a good biocompatibility, except for the study of Sheu et al who reported complications associated to massive strong adhesion [81].…”

“…In addition, the author wishes to acknowledge Prof. Pietro Rossi, Head of the Ophthalmology Ward at "San Martino" Hospital of Genova (Italy) for fruitful discussions, useful suggestions and really essential help. B, S P [104][105][106] 1972 Hydrogels B P [85][86][87][88][89][90][91][92][93][94][95][96][97][98][99][100][101] 1976 Fibrin B A [136,137] 1977 Silver clasp B R [107] 1978 Skin (allograft) B A [119][120] 1981 ePTFE (Goretex) B [77][78][79][80][81] 1985 Polyurethane foam B A [142,143] 1988 Dura mater (allograft) B A [117] 1989 Inflatable peribulbar balloon (B) R [33] 2000 ePTFE-coated silicone implant B P [82][83][84] 2001 Pericardial patch (allograft) B A [118] 2005 PLDLA B A [151,152] 2008 Collagen/glycosaminoglycan polymer B A [122] a B = buckle; S = suture(s) inducing the buckling effect.…”

The Use of Polymers in the Treatment of Retinal Detachment: Current Trends and Future Perspectives

“…Porous expanded PTFE (e-PTFE) was proposed in the form of buckling bands [60][61][62][63][64] or, more recently, as coating on silicone implants [65][66][67] with variable and controversial outcomes. Potentially, the material could be an alternative to silicone, but further studies of its performances and effects in vivo are necessary.…”