Abstract
Abstract: :
Purpose:Aim of this study is to evaluate the corneal host-donor interface after Deep Lamellar Keratoplasty (DLK) in patients with keratoconus. Methods:DLK is a non perforating keratoplasty obtained realizing a stromal lamellar dissection till the endothelial-descemetic plane. The donor graft, without the endotelial-descemetic complex, is fixed with a continuous suture. DLK was performed in 31 patients which underwent a complete ophthalmological examination including best corrected visual acuity, slit-lamp examination, corneal topography, tonometry and pachimetry. In all patients Ultrasound Biomicroscopy (UBM) was performed before and 3 months after surgery. Results:The UBM displayed a single hyperreflective line due to the host descemetic membrane when the lamellar dissection was complete and another weaker reflective line due to the host-donor junction in 93.6% when a thin residual stromal layer was still present. In one patient with visual acuity 12/20 (the lower in our series) this line was highlighted in the optical zone probably for the surgeon's learning curve. In all the other patients the best corrected visual acuity was ≷ 16/20, and no double line in the optical zone was evident. If the second line is imaged out of the optic zone the refractive result is not affected. The mean post operative astigmatism was 2.40 ± 0.92 diopters. A stepless suture zone was present in 96.8%. Conclusion:DLK is a safe and effective procedure in the treatment of Keratoconus or the superficial corneal diseases because of the anterior chamber is not opened. The descemetic plane allows a better placing of the graft, with a stepless junction area, thus reducing the postoperative astigmatism. UBM showed that a complete host corneal lamellar dissection is usually obtained with DLK and this is critical in central area for obtaining a good visual acuity.
Keywords: 369 cornea: clinical science • 450 keratoconus • 544 refractive surgery