Single-piece femtosecond-assisted mushroom keratoplasty in children

Penetrating Keratoplasty With Minimal Endothelial Replacement: A Novel Technique for High-Risk Large-Diameter Corneal Grafting

PURPOSE

The purpose of this study was to analyze the outcome of large-diameter penetrating keratoplasty with minimal endothelial replacement (PKMER).

METHODS

Two eyes (2 patients) with advanced keratoconus and central full-thickness pathology, namely, scar and failed graft, were studied. Both eyes had relatively healthy endothelium in the periphery. They were operated using the PKMER technique that involved a large-diameter keratoplasty with retained central island of endothelium in the donor corresponding to the visual axis, whereas the peripheral Descemet membrane was removed. In effect, the peripheral endothelium and deep stroma of the recipient were preserved. Patients were followed up using anterior segment optical coherence tomography and specular microscopy postoperatively for a minimum period of 6 months in one eye and 3 years in the other.

RESULTS

In both eyes, the central cornea maintained clarity throughout follow-up. The astigmatism reduced significantly, and the final uncorrected and best-corrected vision improved from hand motions close to the face to 6/12/n8 in one eye and 6/12/n12 in the other. Anterior segment optical coherence tomography in both eyes showed satisfactory apposition of interfaces at 1 month postkeratoplasty, and the same was maintained throughout follow-up. Both eyes withstood phacoemulsification for preexisting cataracts, which was performed in the second sitting after the PKMER. There were no complications noted except a temporary initial detachment of the peripheral interface in some quadrants in the early postoperative period.

CONCLUSIONS

PKMER may be considered as an alternative technique to large-diameter full-thickness keratoplasty. It is a relatively easier and cost-effective manual technique, which may be used as an alternative to traditional mushroom keratoplasty in selected cases.

Application of Femtosecond Laser in Anterior Segment Surgery

Femtosecond laser (FSL) is a near-infrared laser that can create reliable and reproducible tissue cutting with minimal damage to adjacent tissue. As the laser can also create incisions with various orientations, depths, and shapes, it is expected to be a useful tool for anterior segment surgery, such as cornea, refractive, and cataract surgery. In this review, the authors will introduce the application of FSL in various anterior segment surgeries and discuss the results of studies regarding the efficacy and safety of FSL in cornea, refractive, and cataract surgery. Experimental studies regarding the potential use of FSL will also be introduced. The studies discussed in this review suggest that FSL may be a useful tool for improving the prognosis and safety of surgeries of the anterior segment.

Shaped corneal transplantation surgery

Since its inception in 1905, keratoplasty techniques have continuously evolved. Shaped keratoplasty procedures have allowed corneal surgeons to use complex graft-host junctions and non-circular graft designs to optimise wound strength and healing, facilitate early suture removal and expedite visual rehabilitation. While this was initially limited to penetrating procedures, shaped lamellar keratoplasty techniques have since emerged. Furthermore, the arrival of femtosecond laser has dramatically increased the range of graft designs available to surgeons, due to the technology's ability to precisely cut complex wound edges. This review describes the broad range of shaped keratoplasty grafts currently available and elaborates on their respective advantages and disadvantages in relation to conventional keratoplasty.