The aim of this study is to assess if an adhesive biopolymer, sodium hyaluronate (NaHA), has synergistic effects with s-PRGF (a serum derived from plasma rich in growth factors and a blood derivative that has already shown efficacy in corneal epithelial wound healing), to reduce time of healing or posology. In vitro proliferation and migration studies, both in human corneal epithelial (HCE) cells and in rabbit primary corneal epithelial (RPCE) cultures, were carried out. In addition, we performed studies of corneal wound healing in vivo in rabbits treated with s-PRGF, NaHA, or the combination of both. We performed immunohistochemistry techniques (CK3, CK15, Ki67, ß4 integrin, ZO-1, α-SMA) in rabbit corneas 7 and 30 days after a surgically induced epithelial defect. In vitro results show that the combination of NaHA and s-PRGF offers the worst proliferation rates in both HCE and RPCE cells. Addition of NaHA to s-PRGF diminishes the re-epithelializing capability of s-PRGF. In vivo, all treatments, given twice a day, showed equivalent efficacy in corneal epithelial healing. We conclude that the combined use of s-PRGF and HaNA as an adhesive biopolymer does not improve the efficacy of s-PRGF alone in the wound healing of corneal epithelial defects.

The vision impairments suffered by millions of people worldwide and the shortage of corneal donors show the need of substitutes that mimic native tissue to promote cell growth and subsequent tissue regeneration. The current study focused on the in vitro assessment of protein-based biomaterials that could be a potential source for corneal scaffolds. Collagen, soy protein isolate (SPI), and gelatin films cross-linked with lactose or citric acid were prepared and physicochemical, transmittance, and degradation measurements were carried out. In vitro cytotoxicity, cell adhesion, and migration studies were performed with human corneal epithelial (HCE) cells and 3T3 fibroblasts for the films’ cytocompatibility assessment. Transmittance values met the cornea’s needs, and the degradation profile revealed a progressive biomaterials’ decomposition in enzymatic and hydrolytic assays. Cell viability at 72 h was above 70% when exposed to SPI and gelatin films. Live/dead assays and scanning electron microscopy (SEM) analysis demonstrated the adhesion of both cell types to the films, with a similar arrangement to that observed in controls. Besides, both cell lines were able to proliferate and migrate over the films. Without ruling out any material, the appropriate optical and biological properties shown by lactose-crosslinked gelatin film highlight its potential for corneal bioengineering.

The transplantation of expansions of limbal epithelial stem cells (LESC) remains one of the most efficient therapies for the treatment of limbal stem cell deficiency (LSCD) to date. However, the available donor corneas are scarce, and the corneas conserved for long time, under hypothermic conditions (after 7 days) or in culture (more than 28 days), are usually discarded due to poor viability of the endothelial cells. To establish an objective criterion for the utilisation or discarding of corneas as a source of LESC, we characterized, by immunohistochemistry analysis, donor corneas conserved in different conditions and for different periods of time. We also studied the potency of LESCs isolated from these corneas and maintained in culture up to 3 cell passages. We hoped that the study of markers of LESCs present in both the corneoscleral histological sections and the cell cultures would show the adequacy of the methods used for cell isolation and how fit the LESC enrichment of the obtained cell populations to be expanded was. Thus, the expressions of markers of the cells residing in the human limbal and corneal epithelium (cytokeratin CK15 and CK12, vimentin, Collagen VII, p63α, ABCG2, Ki67, Integrin β4, ZO1, and melan A) were analysed in sections of corneoscleral tissues conserved in hypothermic conditions for 2-9 days with post-mortem time (pmt) < 8 h or for 1 day with pmt > 16 h, and in sclerocorneal rims maintained in an organ culture medium for 29 days. Cell populations isolated from donor corneoscleral tissues were also assessed based on these markers to verify the adequacy of isolation methods and the potential of expanding LESCs from these tissues. Positivity for several putative stem cell markers such as CK15 and p63α was detected in all corneoscleral tissues, although a decrease was recorded in the ones conserved for longer times. The barrier function and the ability to adhere to the extracellular matrix were maintained in all the analysed tissues. In limbal epithelial cell cultures, a simultaneous decrease in the melan A melanocyte marker and the putative stem cell markers was detected, suggesting a close relationship between the melanocytes and the limbal stem cells of the niche. Holoclones stained with putative stem cell markers were obtained from long-term, hypothermic, stored sclerocorneal rims. The results showed that the remaining sclerocorneal rims after corneal transplantation, which were conserved under hypothermic conditions for up to 7 days and would have been discarded at a first glance, still maintained their potential as a source of LESC cultures.

Purpose: To establish new criteria for the progression of keratoconus, taking into account a Pentacam HR (high resolution) tomographeŕs repeatability limit. Methods: This is a retrospective observational study, including 224 eyes in 154 patients diagnosed with keratoconus and patients treated with crosslinking, with a follow-up of at least one year, in which the new progression score of the Cruces University Hospital for keratoconus progression was analyzed. This score takes into account: maximum keratometry, thinnest corneal thickness, maximum posterior elevation, vertical coma and RMS of high order aberrations, all based on the tomographer repeatability limit. The effectiveness or not of crosslinking was determined. Results: The Receiver Operating Characteristics (ROC) curves obtained in our validation met the criteria by being far from the reference diagonal. Moreover, young patients are more likely to have keratoconus that progresses, and the percentage of patients that showed progression was 14.3% of the eyes studied, with the most advanced keratoconus showing the least progression. Taking into account the new progression score of the Cruces Hospital, we would have indicated crosslinking in 2 eyes only and we observed that none progressed one year after treatment. Conclusions: The the new progression score of the Cruces University Hospital is a method based on the real repeatability limit for keratoconic eyes. Moreover, it is easy to interpret and can be implemented with Pentacam software. It provides a numerical value that evaluates both the anterior and posterior surfaces of the cornea and corneal aberrations in the evolution of keratoconus.

To describe the visual manifestations of brain neoplasms, and to analyze the effect of tumor control on these. This is a descriptive retrospective study, which includes patients under 14 years of age, suffering from different brain neoplasms in our hospital between 1996 and 2005 inclusive. In the group of patients with low visual acuity, 44% had organic amblyopias. In 28% of cases, the amblyopia was secondary to the strabismus/nystagmus produced by the developing tumor. Corrective treatment was successful in some cases of partial or total organic amblyopia. Ophthalmologic evaluation (including perimetry and fundoscopy) enabled detection of 3 tumor relapses. Visual analysis (visual acuity, perimetry, fundoscopy) should be an essential component of assessment during brain neoplasm treatment and follow-up. Corrective treatment is sometimes successful in organic amblyopias