Amniotic membrane transplantation for partial limbal stem cell deficiency

Abstract

Aim-To examine the eYcacy, safety, and long term outcomes of amniotic membrane transplantation for corneal surface reconstruction in cases of partial limbal stem cell deficiency. Methods-17 eyes of 15 patients with partial limbal stem cell deficiency underwent superficial keratectomy of the conjunctivalised corneal surface followed by amniotic membrane transplantation. Cases were followed up for at least a year. Results-All eyes exhibited a stable, intact corneal epithelial surface after a mean follow up period of 25.8 months with no eyes developing recurrent erosion or persistent epithelial defect. The mean time to re-epithelialisation was 22.8 days. Overall improvement in visual acuity was observed in 92.9% of 14 eyes with visual potential. Of those, five eyes gained six or more lines, two eyes gained between four and five lines, six eyes gained between one and three lines, and one eye lost three lines of Snellen acuity. Pain and photophobia were abolished in 86% of cases and substantially reduced in 14%, with all eyes exhibiting decreased vascularisation and inflammation at final follow up. Conclusions-Amniotic membrane transplantation appears to be a safe and eVective method of restoring a stable corneal epithelium for cases of partial limbal stem cell deficiency and can be considered as an alternative to limbal autograft or allograft. (Br J Ophthalmol 2001;85:567-575)

Corneal sensitivity and ocular surface changes following preserved amniotic membrane transplantation for nonhealing corneal ulcers

“…Failure of attainment of corneal epithelial phenotype of healing in case 9 reconfirmed the common belief that AMT alone is insufficient in cases with total limbal dysfunction. 27 The initial and consistent finding in all patients was a reduction in the ocular inflammation in the early phase after AMT as evidenced by a decrease of conjunctival and limbal hyperaemia, and corneal oedema. We observed that AMT could improve visual acuity, probably owing to both corneal surface restoration and improvement of corneal transparency.…”

Niche regulation of corneal epithelial stem cells at the limbus

“…Many diverse action mechanisms have been ascribed to the amniotic membrane for its supplanting with a new basement membrane and a stroma that can suppress inflammation, scarring and angiogenesis (for review see [95]). Importantly, amniotic membrane transplantation alone is sufficient to restore the normal corneal epithelial phenotype in human corneas with partial limbal SC deficiency [96][97][98], indicating that amniotic membrane helps expand residual limbal epithelial SCs in vivo. The above clinical discovery has led others to successfully transplant such an ex vivo expanded human limbal epithelial tissue to treat human corneas with total limbal SC deficiency [34,99,100].…”

Membrana amniótica na reconstrução da superfície ocular após exérese de carcinoma de células escamosas da conjuntiva

“…As propriedades antiinflamatórias, antiangiogênicas e moduladoras da cicatrização da membrana amniótica puderam ser constatadas pelo bom aspecto clínico pós-operatório da maioria dos casos estudados, que apresentaram superfície córneo-conjuntival mais estável, sem erosões e com menos inflamação ou formação de cicatrizes (17,(20)(21) . Alguns autores mostraram resultados satisfatórios com a utilização de membrana amniótica como enxerto após remoção de tumores conjuntivais em 16 olhos (3,16) .…”