Safety of Hyaluronic Acid in Postoperative Treatment after Penetrating Keratoplasty

Background The objective of this clinical trial was to confirm the safety of phosphate-free high molecular weight hyaluronate (HYLO (R)-GEL) as lubricant for postoperative care after penetrating keratoplasty. Patients and Methods 51 eyes were followed up 6 weeks after penetrating keratoplasty under therapy with phosphate-free high molecular weight hyaluronate. Visual acuity, intraocular pressure, conjunctival hyperaemia, conjunctival chemosis, corneal fluorescein staining, corneal infiltrates, corneal endothelial-epithelial decompensation, Descemet's folds, Tyndall effect, cells in the anterior chamber and subjective assessment of lacrimation, foreign body sensation, pressure sensation, burning, mucus and itching were recorded on the first, third and fifth postoperative days and six weeks postoperatively. Tolerance was rated by the patient and the attending ophthalmologist. Results The following objective parameters improved significantly from day 1 to week 6 in patients treated with phosphate-free high molecular weight hyaluronate: visual acuity, conjunctival hyperaemia, conjunctival chemosis, corneal fluorescein-staining, corneal endothelial-epithelial decompensation, Descemet's folds, the maximum diameter of corneal erosion, Tyndall effect and cells in the anterior chamber. In addition, there was significant improvement in the course of the following subjective complaints: lacrimation, foreign body sensation, pressure sensation and itching. In total 63% (32/47) of the study patients reported excellent local tolerance of phosphate-free high molecular weight hyaluronate on day one postoperatively. This proportion rose to 86% (37/43) 6 weeks postoperatively. The safety of phosphate-free high molecular weight hyaluronate was rated by the ophthalmologists as "perfect" in 92%, as "acceptable" in 6% and as "unacceptable" in 2% of eyes. ConclusionTherapy with phosphate-free highmolecular weight hyaluronate results in significant improvements in objective findings and subjective symptoms after penetrating keratoplasty. Tolerance was rated as "excellent" by the ophthalmologist in 92% of patients in the early postoperative follow-up.