Donor corneas can be preserved for 11 days: Study

New York Nov 11 (IANS) Corneal donor tissue can be safely stored for 11 days without negatively impacting the success of a transplant a clinical trial has shown.

Currently donor corneas -- the eye s clear outer covering -- are generally not used for surgery if they have been preserved for longer than seven days.

Expanding the window in which donor tissues can be considered suitable "by even just a few days" should help safeguard quality donor tissue and access to vision-saving transplantation procedures the researchers said.

"The current practice of surgeons to use corneas preserved for no longer than seven days is not evidence-based.

"Rather that practice is based on opinion which hopefully will change with this new evidence " said lead investigator Jonathan Lass from the Case Western Reserve University.

For the study appearing in the journal JAMA Ophthalmology the team looked at three-year graft success rates among a total of 1 090 individuals (1 330 eyes) who underwent cornea transplant via Descemet s stripping automated endothelial keratoplasty by 70 surgeons at 40 surgical sites.

Overall the three-year success rates were the same for corneas preserved for eight-to-14 days compared with up to seven days (92.1 per cent versus 95.3 per cent).

In a separate analysis the team analysed the extent of endothelial cell loss (ECL) -- the loss of cells in the corneal endothelium that continued to occur as a normal part of ageing in the grafted donor cornea three years after it had been transplanted.

They non-invasively measured ECL in the 945 eyes with successful grafts and found that corneas preserved up to seven days had a 37 per cent loss of cells versus a 40 per cent loss in corneas preserved for eight-to-14 days.

Taken together the separate analyses looked at graft success rates and ECL support that used corneas stored up to 11 days the researchers said.

--IANS
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