Freeze -Dried Amniotic Membrane Transplantation: In expensive Tectonic Support in complicated

Infectious Keratitis Cases

Hatem Kobtan MD FRCS (Ed) (Glasg) Dina Kobtan MDCairo University

The authors have no financial disclosure

Aim of Work To evaluate the efficacy and safety of Freeze dried amniotic membrane

transplantation (FD-AMT) as a tectonic support (Biologic contact lens) in cases of keratitis with corneal perforation, descemetocele and melting.

Freeze dried AMT Kobtan World Cornea Congress 2010

Fig (A) FD AM held with forceps as a sheet. (B) H and E stain of the membrane showing a single epithelial layer and underlying stroma.

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This study involved a prospective, non-comparative, interventional case series.

11 eyes of 11 patients with infectious keratitis were enrolled.

The FD-AM application consisted of an overlay technique. The AM was secured by interrupted 8-0 Vicryl sutures placed just outside the limbus.

After surgery all patients continued to receive their appropriate antimicrobials medications until inflammation had subsided.

FD-AM invariably dissolved over the course of approximately one week. Multiple application of AM was not necessary except in case 10 and 11.

Material and Methods

Current opinion ophthalmology. Volume 12(4). 2001

Freeze dried AMT Kobtan World Cornea Congress 2010

30-1-07

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Case 1: (A) Color photo showing deep corneal ulcer measuring 5X 5 mm reaching down to the level of descemet’s membrane ( Blue arrow) with surrounding superficial and deep corneal vascularization (Yellow arrow) (B) Shows formation of a vascularized leukoma 8 weeks post FD AMT.

Case 1

Freeze dried AMT Kobtan World Cornea Congress 2010

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Case 2 : (A) Color photo showing corneal perforation (Black arrow) with lost anterior chamber and positive Seidel testing. (B) Four weeks following FD-AMT with formation of a vascularized leukoma.

Case 2

Freeze dried AMT Kobtan World Cornea Congress 2010

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Case 3

Freeze dried AMT Kobtan World Cornea Congress 2010

Case 3 : ( A ) Color photo showing peripheral corneal melting (Blue arrow). (B) A vascularized leukoma is seen 8 weeks post FD-AMT.

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Case 4: (A) Color photo shows central huge descemetocele (Green arrow) that subsequently developed in the area of corneal thinning . (B) Nine weeks post FD-AMT shows complete resolution of the descemetocele.

Case 4

Freeze dried AMT Kobtan World Cornea Congress 2010

Complete epithelialization with stromal rebuild under the transplanted membrane was achieved in all cases with two exceptions case 10 and 11 which showed persistent localized central thinning most likely due to LSCD.

All patients demonstrated resolution of the ocular inflammation with no recurrence of infection in any of the treated patients during the mean follow-up of 1 month to 2 years.

Results

Freeze dried AMT Kobtan World Cornea Congress 2010

FD-AMT was effective for treating corneal descemetocele, corneal perforation and melting of moderate severity associated with infectious keratitis when used with the appropriate antimicrobial.

AMT offers the following advantages over tectonic corneal grafts and conjunctival flaps including avoidance of potential complications of corneal transplantation including allograft rejection; Feasibility of AMT in places where there is a shortage of cornea tissues and preservation of patient’s cosmetic appearance without covering of the cornea with vascularized conjunctival tissue..

This novel and promising biomaterial may be a useful alternative to cryopreseved –AMT. It may be even advantageous with regards its ready availability, sterililization and production costs.

Freeze dried AMT Kobtan World Cornea Congress 2010

Conclusion

FDA has not approved the use of the freeze dried AM. FDA has concluded that removal of cytokine containing cells from FD tissue would interfere with human amniotic membrane's ability to actively mediate wound repair and wound healing.

Warning

1. Lee 19.Takahiro Nakamura, Makoto Yoshitani, Helen Rigby, Nigel J. Fullwood, Wakana Ito, Tsutomu Inatomi, Chie Sotozono, Tatsuo Nakamura, Yasuhiko Shimizu, and Shigeru Kinoshita1. Sterilized, Freeze-Dried Amniotic Membrane: A Useful Substrate for Ocular Surface Reconstruction. Investigative Ophthalmology and Visual Science 2004; 45:93-99. 2. Sippel, Kimberly C., Ma, Joseph J.K. ; Foster, C. Stephen: Amniotic membrane surgery. Current openion ophthalmology 12(4) 2001 269-281.

3. SH, Tseng SCG. :Amniotic membrane transplantation for persistent epithelial defects with ulceration. Am J Ophthalmol 1997;123: 303–12. 4. Kruse FE, Rohrschneider K, Volcker HE: Multilayer amniotic membrane transplantation for reconstruction of deep corneal ulcers. Ophthalmology 1999, 106: 1504–1511. 5. Letko E, Stechschulte SU, Kenyon KR, et al .: Amniotic membrane inlay and overlay grafting for corneal epithelial defects and stromal ulcers. Arch Ophthalmol 2001, 119: 659–663.

References