Abstract:

Objective To compare the clinical efficacy of deep anterior lamellar keratoplasty (DALK) using acellular porcine corneal stroma and fresh corneal tissue for the treatment of infective corneal ulcer. Design Retrospective case series. Participants Ten patients with infectious corneal ulcer admitted to Beijing You'an Hospital from Nov 2015 to Sep 2016, all patients’ Descemet’s layer was not affected. Methods Bubble-assisted DALK surgery data were retrospectively analyzed. Patients were assigned to acellular porcine corneal stroma treatment group and fresh corneal tissue treatment group with five cases in each treatment group. The best corrected visual acuity (BCVA)(LogMAR), intraocular pressure(IOP), spherical power on optometry, mean corneal curvature, astigmatism on corneal topography, corneal endothelial cell count, corneal thickness(CT), axial length(AL), corneal structure under confocal microscope, corneal transparency and grafts survival were observed one year after operation. Main Outcome Measures The BCVA (LogMAR), IOP, spherical power on optometry, mean corneal curvature, astigmatism on corneal topography, corneal endothelial cell count, CT, AL, corneal structure under confocal microscope, corneal transparency and grafts survival. Results During follow-up, all the grafts in both groups remained clear and the graft survival rate was 100%. BCVA was 0.53±0.21 in the acellular porcine corneal stroma group and 0.33±0.06 in the fresh corneal tissue group (P=0.184), the IOP was (8.00±2.00) mmHg and (10.33±0.58) mmHg (P=0.124), the spherical power was (-4.50±4.21) D and (-1.25±0.75) D (P=0.258), the mean corneal curvature was (47.59±5.40) D and (44.51±1.87）D (P=0.403), the astigmatism was (-5.52±1.97) D and (-5.14±1.66)D on corneal topography (P=0.812), the endothelial cell count was (1272.67±387.63)/mm2 and (1550.33±232.69)/mm2 (P=0.347), the CT was (439.33±67.86)μm and (534.00±14.42)μm(P=0.077), and the AL was (23.53±0.91)mm and (23.55±1.56)mm in the two groups respectively (P=0.981).  Corneal confocal microscopy showed that the corneal epithelial cells in the acellular porcine corneal stroma group could completely cover the graft. The shape and density of the basal cells and the wing cells were similar to that of the fresh cornea. However, high-reflective deposits were observed under the basal cells, and the density of the stroma cells was significantly lower than that of fresh corneal tissue. Moreover, acellular fibers were still observed between the endothelial cells and the deep stroma. Conclusion Acellular porcine corneal stroma has good biocompatibility and could be an alternative treatment with satisfactory results for infectious corneal ulcer when fresh corneal tissue is not available.

Key words: acellular porcine corneal stroma, fresh corneal tissue, deep anterior lamellar keratoplasty, infectious corneal ulcer