Clinical application of a shape-preserving rapid corneal donor dehydrater

AIM:To describe the design and clinical application of a corneal donor dehydrator which can quickly dehydrate corneas and keep its original shape.METHODS:The corneal donor material is placed on stainless steel beads with different diameters in the dehydrating box to make the cornea the same shape as the steel ball.Then,the cornea is placed inside the dehydrater for rapid dehydrating using the internal cleaning and ventilation system.Totally 83 eyes underwent deep anterior lamellar keratoplasty(DALK)using corneal donor tissue preserved with corneal dehydrater,and 60 patients(60 eyes)received DALK by the same surgeon using corneal donor tissue preserved with glycerol were included in the control group.The best corrected visual acuity(BCVA),the thickness and transparency of the corneal buttons were recorded.RESULTS:After the completion of dehydrating,all the donor corneas maintained a normal shape without any shrinkage or distortion,and the average intraoperative rehydration time was 43.3±12.1 s during operation.The mean BCVA of the dehydrater group was 0.30±0.18 at 1 wk and 0.32±0.16 at 1 mo,which were statistically better than that of the control group(P<0.001).The score of corneal buttons transparency were lower than that of the control group with statistical difference(P<0.001).The thickness of corneal buttons at 1 wk and at 1 mo in the dehydrater group was significantly better than that of the control group respectively(P<0.001).One week after operation,no corneal button turbidity or edema was observed in both groups.CONCLUSION:The dehydrater can quickly dehydrate the corneal material in a clean and airtight environment and maintain the original shape of the corneal donor during the dehydrating process.This dehydrater is recommended for long-term high-quality preservation in areas where corneal materials cannot be used within a reasonable time period.

Donor cornea quality used for penetrating keratoplasty vs deep anterior lamellar keratoplasty

Deep anterior lamellar keratoplasty(DALK) has recently been introduced as an alternative procedure to penetrating keratoplasty(PK) for corneal pathologies not affecting the corneal endothelium. DALK does not rely on donor endothelium and requires less rigid criteria for donor corneal tissue quality. Therefore, DALK makes it possible to use donor corneas deemed unsuitable for PK. Furthermore, lamellar keratoplasty allows acellular corneal tissue to be transplanted. As a result, long-term preservation techniques are being revisited to increase the availability of donor corneas and subsequently alleviate constraints of availability, cost, storage, and transportation in many countries. The recent alterations in corneal transplantation techniques and hence the type of donor cornea tissues used for each technique, may require corneal surgeons and eye banks to reevaluate their selection criteria. The purpose of this systematic review is to present an updated analysis on the type and quality of donor corneas used for PK and DALK, assess the influence of donor and eye bank factors on the quality of donor corneas, and determine whether any of these donor factors affect clinical outcomes, complications, and graft survivals.