Implantation of a Synthetic Cornea: Design, Development and Biological Response

Abstract

Our goal was to evaluate 3 different designs of synthetic corneas in vivo. All devices had a transparent hydrogel center molded to a porous peripheral skirt. Over 30 devices were implanted into rabbits and followed for up to 6 months. The devices were preseeded with rabbit stroma1 fibroblasts, which enhanced the rate of fibroplasia. The anterior surface of the hydrogel was modified using argon rf plasma treatments. Clinical examinations were performed, and histological analyses were conducted on tissue throughout the time course. Our optimal model ranged from 4.5 to 6 mm and had an extended porous skirt increasing the surface area for fibroplasia and ultimate anchorage of the device. Fibroplasia occurred in this model, and collagen was detected by 28 days. The anterior chamber was normal with no detectable leakage of aqueous humor. Glycosaminoglycans were detected and followed the time course outlined previously when porous material itself was inserted into the stroma. We present the first demonstration that rabbit limbal epithelial cells can migrate onto the synthetic cornea in vivo.

Regeneration of corneal epithelium utilizing a collagen vitrigel membrane in rabbit models for corneal stromal wound and limbal stem cell deficiency

“…Apart from use of AM, it is well known that most applications of biomaterials delay corneal epithelialization (Trinkaus‐Randall et al. ; Hicks et al. ; Ma et al.…”

“…In addition, AM is not transparent, a key shortcoming for visual acuity. Apart from use of AM, it is well known that most applications of biomaterials delay corneal epithelialization (Trinkaus-Randall et al 1997;Hicks et al 2003;Ma et al 2005;Miyashita et al 2006). The ability of a prospective graft material to facilitate a similar rate of epithelialization as the native cornea would indicate that such a material holds promise as an option for corneal grafting.…”

Future Design of a New Keratoprosthesis. Physical and Biological Analysis of Polymeric Substrates for Epithelial Cell Growth

“…6 Keratoprostheses should be implanted in a similar way to penetrating keratoplasty. 1,7 Different research groups have synthesized materials to develop an artificial keratoprosthesis (Legais and co-workers, [8][9][10][11][12][13] Chirila and co-workers, [14][15][16][17][18] Trinkaus-Randall and coworkers, [19][20][21][22][23] and von Fischern et al 24 ). Clinical trials using Chirila keratoprosthesis (polyhydroxyethyl methacrylate hydrogel) showed that thick synthetic biocompatible structures can be maintained in the cornea without risk of extrusion, helped by fibroblast ingrowth onto the peripheral portion.…”

Mallas macroporosas bioestables con aplicación en implantes protésicos y trasplante de células.

“…Analizando el proceso completo (comentado en apartado 3. Otro problema importante que se presenta en las membranas fabricadas del modelo core-skirt, es la biointegración de esta con los tejidos circundantes, como ocurre en la Seoul-Type KPro 195,196 , en el modelo propuesto por Trinkaus-Randall et al 192 En caso de implantación de la prótesis, se podría intentar combinar este modelo con sistemas de liberación controlada para mejorar la biointegración, tal y como probó el grupo de Trinkaus et al 193 , o bien implantar la prótesis con un recubrimiento previo de proteínas involucradas en la adhesión 58,192 y/o sembrada con células.…”

“…Entre dichos inconvenientes se destacan, la deposición de partículas en fumadores y formación de depósitos de calcio, tras someter al paciente a determinados tratamientos con fármacos [205][206][207] 192,194 .…”