Effects of a Novel Push-through Technique Using the Implantable Collamer Lens Injector System for Graft Delivery during Endothelial Keratoplasty

PURPOSE: To investigate effects of a new push-through insertion method for donor lenticules using an injector system on endothelial viability ex vivo and in a clinical case series of endothelial keratoplasty. METHODS: An ex vivo delivery model was used with porcine corneoscleral rims. We compared the endothelial viability in a new push-through insertion method using the Visian Implantable Collamer Lens (ICL) injector versus that of standard forceps-assisted insertion for lenticule delivery. Twenty porcine corneal lenticules were divided into four groups by insertion method and wound size. Vital dye staining was performed and devitalized areas were semi-quantitatively assessed by digital imaging. In the clinical case series, Descemet's stripping endothelial keratoplasty (DSEK) using the push-through method was performed in seven patients and endothelial outcome was determined six months postoperatively. RESULTS: Mean devitalized areas for the push-through method were significantly lower than for forceps-assisted insertion through 3.2 mm incision (23.99 +/- 2.17% vs. 50.48 +/- 5.07%, p = 0.009) in the ex vivo model. Average endothelial cell counts of donor tissues of patients who underwent DSEK were 26.4% lower six months postoperatively. CONCLUSIONS: Push-through delivery of donor lenticules using the Visian ICL injector system appears to be less harmful to endothelial cells than conventional forceps-assisted delivery.

Effects of a Novel Push-through Technique Using the Implantable Collamer Lens Injector System for Graft Delivery during Endothelial Keratoplasty

PURPOSE: To investigate effects of a new push-through insertion method for donor lenticules using an injector system on endothelial viability ex vivo and in a clinical case series of endothelial keratoplasty. METHODS: An ex vivo delivery model was used with porcine corneoscleral rims. We compared the endothelial viability in a new push-through insertion method using the Visian Implantable Collamer Lens (ICL) injector versus that of standard forceps-assisted insertion for lenticule delivery. Twenty porcine corneal lenticules were divided into four groups by insertion method and wound size. Vital dye staining was performed and devitalized areas were semi-quantitatively assessed by digital imaging. In the clinical case series, Descemet's stripping endothelial keratoplasty (DSEK) using the push-through method was performed in seven patients and endothelial outcome was determined six months postoperatively. RESULTS: Mean devitalized areas for the push-through method were significantly lower than for forceps-assisted insertion through 3.2 mm incision (23.99 +/- 2.17% vs. 50.48 +/- 5.07%, p = 0.009) in the ex vivo model. Average endothelial cell counts of donor tissues of patients who underwent DSEK were 26.4% lower six months postoperatively. CONCLUSIONS: Push-through delivery of donor lenticules using the Visian ICL injector system appears to be less harmful to endothelial cells than conventional forceps-assisted delivery.

The Effect of Minor Components and Growth Factor Added to Corneal Storage Medium on the Viability of Corneal Endothelium

PURPOSE: This study has been conducted to evaluate morphologic and functional changes of cat corneal endothelium preserved in Likorol , locally prepared medium and locally prepared medium with growth factor, respectively. METHODS: To know the morphologic change of the dornea, cat corneal endothelia stored in three different medium are examined by specular microscopy and the change of central corneal thickness was measured by light microscopy from the distance of between epithelum and endothelium. We also examined the corneal endothelium of each group by scanning electronmicroscopy. To know the functional change of the cornea, alkaline phosphatase released to each preservation medium was measured with biochemical analyzer. RESULTS: The change of corneal thickness was remarkable in locally prepared medium (group LL)up to 4 days of preservation and specular microscopic change of endothelial cell density, polymegathism and pleomorphism was significantly notable in locally prepared medium (group LL). The morphologic change examined by scanning electron microscopy was significantly notable in locally prepared medium with growth factor (group LLG). The alkaline phosphatase activity at the 6th preservation day was higher in locally prepared medium with growth factor (group LLG) than in Likorol (group L). CONCLUSIONS: The viability of corneal endothelium in corneal storage medium with minor components and growth factor is significantly higher than that without minor components and growth factor.