Sir,

Thank you for the opportunity to respond to the comments made by Drs MS Abu-Ain and SK Webber1 in response to our paper related to amniotic membrane transplantation.2

Drs Abu-Ain and Webber have described a neat little trick to apply amniotic membrane to the ocular surface without actually having to suture it in place. This is a variation of the theme described by us in our paper, wherein we wrapped a conformer shell with amniotic membrane and placed it in the conjunctival sac. Clearly, there will be specific indications where this approach of wrapping the amniotic membrane around a Flieringa ring may help, for example, with a persistent corneal epithelial defect.

A Flieringa ring, however, is a scleral fixation ring and is not designed to extend deep into the conjunctival fornices, unlike a conformer shell. In contrast, the conformer benefits from being moulded to the shape of the eye and is a better fit than the ring. However, this is a minor difference and may bear no actual influence on the outcomes. In cases in which the palpebral and bulbar surfaces of the conjunctiva are denuded or inflamed, as after chemical burns or acute Stevens Johnson syndrome, an amnion-covered conformer shell is more likely to keep the surfaces apart at the fornix compared with the Flieringa ring.

The authors claim ‘several advantages’ stating that their method is cheap, easily performed, well tolerated by the patient, examination of the eye is possible through the amnion, and can be removed and replaced whenever necessary with negligible trauma to the eye. All the above apply equally to the conformer shell, wherein the central hole also allows visualisation of the cornea. The patients for whom we used it tolerated it well. Conformer shells without amnion wrap have been used following buccal mucosal grafts to the conjunctiva and retained in situ for months with good patient comfort.

Both methods will be much cheaper than the commercially available option and either can be used depending on the clinical need. In order to determine whether one is superior to the other, a proper clinical trial will be needed, which we do not think is worth the effort.