An Assay System to Evaluate Riboflavin/UV-A Corneal Phototherapy Efficacy in a Porcine Corneal Organ Culture Model.

The purpose of this study was to investigate the response of porcine corneal organ cultures to riboflavin/UV-A phototherapy in the injury healing of induced lesions. A porcine corneal organ culture model was established. Corneal alterations in the stroma were evaluated using an assay system, based on an automated image analysis method able to (i) localize the holes and gaps within the stroma and (ii) measure the brightness values in these patches.

Descemet Membrane Endothelial Keratoplasty Learning Curve for Graft Preparation in an Eye Bank Using 645 Donor Corneas.

Purpose: To investigate the learning curve of Descemet membrane endothelial keratoplasty (DMEK) graft preparation in an eye bank.

Methods: Four operators prepared 645 DMEK grafts using the stripping technique between 2014 and 2017 at the Veneto Eye Bank Foundation, Italy. Endothelial cell loss (ECL) and tissue wastage were recorded retrospectively after DMEK preparation and correlated with the number of tissues prepared each year by each operator.

Recombinant human serum albumin for corneal preservation.

Purpose: To study the performance of a completely synthetic organ culture (OC) preservation system containing recombinant human serum albumin (rHSA) for preservation of human donor corneas.

Methods: Twenty-four paired donor corneas were randomly collected, and one cornea from each donor was preserved in synthetic (experimental) and serum-based media (control). The tissues were assessed at day 0; after 6 days of preservation at room temperature (RT) in Cornea Trans and Cornea Prep II ; after 28 days at 31°C in Cornea Syn [with rHSA] and Cornea Max [with foetal calf serum (FCS)] and; 4-day post deswelling in Cornea Trans and Cornea Jet .

Polarization of human donor corneas.

To investigate the de-orientation effect of DSAEK grafts by observing the cross patterns and polarization power of human donor corneas using a polarizing device (Lumaxis(®)). Forty human donor corneas were placed in small petri-plates with epithelial side facing up. Polarizing power (arbitrary unit) and crosses were monitored and recorded by the software.

Transplantation failure due to inadvertent reversal of human donor corneas.

Purpose: To emphasize and create awareness of the possibility of inadvertently grafting an inverted corneal button and describe 4 cases that showed this phenomenon on human donor corneas during preservation and transportation from an eye bank.

Methods: Three out of 4 tissues showed inadvertent inversion during transportation and 1 was identified as inverted during preservation in the eye bank. Out of the 3 tissues that were shipped, 2 tissues were transplanted and 1 was identified as inverted prior to transplantation and shipped back to the eye bank.

Development of a new superficial punch for Descemet's Membrane Endothelial Keratoplasty donor tissue preparation.

Endothelial Keratoplasty (EK) is a corneal surgical procedure that allows a selective transplantation of the posterior layer of the cornea. Descemet's Membrane Endothelial Keratoplasty (DMEK) is one of the EK procedures in which the diseased Descemet's Membrane and the endothelium are replaced with a healthy donor tissue. To achieve this, the donor cornea is cut superficially from the endothelial side and the tissue can be separated using specific instruments like Pierse Notched, Acute or Fogla forceps.

A superfusion apparatus for ex vivo human eye irritation investigations.

A superfusion apparatus (SA) was developed to maintain isolated human corneas ex vivo under conditions which mimic the natural eye environment in vivo, including controlled temperature, tear flow and intraocular pressure. The SA was designed, developed and tested for use in ophthalmic pre-clinical research and to test new pharmaceutical formulations. Corneas undergo an equilibration process in the new physiological environment for one day.

Preloaded donor corneal lenticules in a new validated 3D printed smart storage glide for Descemet stripping automated endothelial keratoplasty.

Purpose: To design and validate the efficacy of three-dimensional (3D) printed smart storage glide (SSG) which is capable of preserving and delivering posterior lenticules for Descemet stripping automated endothelial keratoplasty (DSAEK).

Methods: Laboratory investigation (A) was followed by clinical validation (B). Unsuitable corneas for transplantation (n=20) were used for study A.

Synthetic versus serum-based medium for corneal preservation in organ culture: a comparative study between 2 different media.

Purpose: To study the effect of a synthetic medium and compare it with a serum-based medium for corneal preservation in organ culture using an overall quality assessment system.

Methods: A randomized study with blinded observers was performed comparing parameters such as thickness, transparency, viable endothelial cell density (VECD), morphology, and overall quality (OQ) of the corneal tissues preserved in synthetic and a serum-based medium, respectively. Seven human paired corneas were randomly selected and assessed at day 0 (initial), day 2 (before organ culture), day 30 (before deturgescence/deswelling storage), and 48 hours post deswelling.

A validated biorepository of retina and choroid tissues for gene expression studies.

Research studies on pathologies affecting the posterior segment of the eye are usually carried out either in animal models or cell lines of human origin that mimic the molecular patterns occurring in the human retina-pigment epithelium-choroid (RPC) complex in vivo. As this is not always the case, we were prompted to validate a biorepository of RPC tissues for research purposes. A PubMed literature search on "retina," "choroid," "bio-bank," or "biorepository" as keywords did not lead to any publication describing the collection and banking of samples from the RPC complex for research purposes.

Bubble technique for Descemet membrane endothelial keratoplasty tissue preparation in an eye bank: air or liquid?

Purpose: To compare the big-bubble method using air and liquid as medium of separation for Descemet membrane endothelial keratoplasty (DMEK) lenticule preparation in an eye bank.

Methods: Donor corneas (n=20) were immersed in liquid [tissue culture medium (TCM)]. Air and liquid was injected using a 25-gauge needle in the posterior stroma or as near to the stroma-Descemet membrane (DM) phase as possible to create a complete bubble of larger diameter.

DMEK lenticule preparation from donor corneas using a novel 'SubHyS' technique followed by anterior corneal dissection.

Purpose: To describe a novel submerged hydro-separation (SubHyS) technique followed by anterior corneal dissection to prepare a Descemet endothelial graft (DEG) for Descemet's membrane endothelial keratoplasty from human donor corneas.

Methods: 30 human donor corneas were immersed in liquid (organ culture (OC) storage medium). Using a 25-gauge needle, approximately 0.

Descemet membrane endothelial keratoplasty tissue preparation from donor corneas using a standardized submerged hydro-separation method.

Purpose: To standardize a novel submerged hydro-separation technique for Descemet membrane endothelial keratoplasty (DMEK) graft preparation from donor corneal tissues.

Design: Experimental study, laboratory investigation.

Setting: The Veneto Eye Bank Foundation, Venice, Italy.

A quantitative method to evaluate the donor corneal tissue quality used in a comparative study between two hypothermic preservation media.

To standardize a new evaluation technique for calculating the overall quality (OQ) of the donor cornea and validate it using a comparative study of corneas preserved in Optisol-GS and Cornea Cold®. Thirty pairs of donor corneas were selected for a 4 week in vitro comparative study using masked observers. Physiological parameters like thickness, transparency, viable endothelial cell density (VECD) and morphology were transformed to numerical range (0-4) to obtain the OQ.

Posterior lamellar graft preparation: a prospective review from an eye bank on current and future aspects.

Descemet membrane endothelial keratoplasty (DMEK) is a corneal surgical technique which selectively replaces the damaged posterior part of the cornea with a healthy donor graft retaining the rest of the tissue intact. There is a need to validate and standardize the donor tissue before grafting due to certain issues that can lead to consequences such as graft failure due to poor endothelial cell count, higher mortality, detachment of the graft, or increased surgical expenses, time, and effort. Thus, prospective potential surgeons and eye banks should now aim at developing new improved surgical techniques in order to prepare the best suited, validated, precut, preloaded, and easy to transplant tissue to reduce pre- and postsurgical complications.

A portable device for measuring donor corneal transparency in eye banks.

To develop a portable device for measuring the donor corneal transparency and validate its efficacy for corneal evaluation in the eye-banks and for research. The transparency device (TD) has a light source, a detachable system for corneal insertion and a base for light transmission. The probe detects the transmitted light which is measured by a lux-meter.

Effect of postmortem interval on the graft endothelium during preservation and after transplantation for keratoconus.

Purpose: To investigate the effect of postmortem intervals and prognostic factors on endothelial cell density (ECD) of human donor corneas during preservation and at 1 and 3 years after transplantation in patients transplanted for keratoconus.

Methods: Two different studies were performed: (1) with 733 donor corneas selected for the preservation study and (2) 64 patients with keratoconus selected retrospectively from 2 hospital clinics. The corneas were evaluated on the basis of the ECD during preservation, study A, and at 1 and 3 years after transplantation, study B.

Banking of donor tissues for descemet stripping automated endothelial keratoplasty.

Purpose: The demands for precut lamellar grafts for Descemet stripping automated endothelial keratoplasty rose in our eye bank from 74 in 2007 to 408 in 2010. To meet this expanding requirement, we explored the possibility to preserve these preparations in organ culture.

Methods: Organ cultured corneas, stored in a medium containing 6% dextran, were mounted on a Moria artificial anterior chamber, deprived of the epithelium and then cut with a microkeratome.

A simplified technique for in situ excision of cornea and evisceration of retinal tissue from human ocular globe.

Enucleation is the process of retrieving the ocular globe from a cadaveric donor leaving the rest of the globe undisturbed. Excision refers to the retrieval of ocular tissues, especially cornea, by cutting it separate from the ocular globe. Evisceration is the process of removing the internal organs referred here as retina.

Pneumatic dissection and storage of donor endothelial tissue for Descemet's membrane endothelial keratoplasty: a novel technique.

Purpose: To investigate the feasibility of pneumatic dissection of donor endothelium and the effect of 7 days of storage in tissue culture medium on the endothelial cell count.

Design: Experimental study.

Participants: We used 20 human donor corneoscleral tissues deemed unsuitable for transplantation.

Improved preparation and preservation of human keratoplasty lenticules.

Purpose: To improve the preparation of lenticules from human cornea and to obtain their preservation without loss of viable keratocytes.

Methods: The epithelium was manually removed after bathing the surface of the cornea with a solution of trypsin and EDTA. Lenticules were prepared by microkeratome resection and viable keratocytes were visualized by staining with thiazolyl blue (MTT).