Long-term results of femtosecond laser-assisted sutureless lamellar keratoplasty for anterior stromal pathologies including recurrent anterior corneal dystophies

Session Details

Session Title: Refractive Corneal Surgery

Session Date/Time: Wednesday 17/09/2014 | 08:00-09:30

Paper Time: 08:35

Venue: Boulevard A

First Author: : M.Taneja INDIA

Co Author(s): :    V. Rathi   P. Vaddavalli   S. Murthy   J. Vazirani   B. Bagga  

Abstract Details

Purpose:

To report the long term visual and refractive outcomes and complications of Femtosecond laser assisted sutureless Anterior Lamellar Keratoplasty (FALK) for anterior stromal corneal pathologies including recurrent anterior corneal dystrophies following primary lamellar or penetrating keratoplasty and/or phototherapeutic keratectomy .

Setting:

Preoperative OCT was performed in all cases to demarcate the level of the opacities and thickness of the cornea in the patients’ eyes. For donor graft preparation, corneo-scleral donor rim was mounted on the Moria artificial chamber and pressure was built up inside and a free cap was created with Visumax 500 kHz femtosecond laser. In all the cases the graft thickness was taken 10 – 20 % more than the recipient’s lenticule because of preexisting oedema in the eyebank eyes. For the preparation of the recipient bed, patients asked to look at the green fixation light in the laser machine. The suction was built up and then the laser was fired. The recipient’s lenticule was removed with the flap lifter. All these surgeries were done using a spiral- out fashion with 2.5 microns spot distance and track distance for the bed and 2.5 microns spot distance and track distance for side cut with an angle of 90º. Thereafter the donor lenticule was placed in prepared host bed and ironed with a surgical sponge to remove any folds and kept pressed for two minutes and then a bandage lens was placed over the lamellar graft. No sutures were placed

Methods:

Fouteen eyes of 14 patients with varying pathologies in the anterior 250 microns of corneal stroma underwent FALK procedure using Visumax 500 kHz femtosecond laser. This included three eyes that had earlier undergone penetrating keratoplasty (PK), two eyes that had undergone deep anterior lamellar keratoplasty (DALK) and five eyes that had undergone phototherapeutic keratectomy (PTK) earlier. Parameters noted included indication for surgery, OCT demarcating the extent of the pathology in the cornea, logMAR visual acuity, pachymetry, duration of follow up, refraction at last follow up. Complications, if any were noted. The Wilcoxon signed rank test was used to analyse difference in logMAR visual acuity before and after surgery.

Results:

Indications for FALK included Gelatinous drop-like corneal dystrophy (three eyes), granular corneal dystrophy (two eyes), Reisbuckler's dystrophy (three eyes), spheroidal degeneration (two eyes) and anterior stromal corneal scar with intrastromal glass foreign body (one eye), corneal scars (three eyes). Anterior lamellar donor corneal tissue was successfully integrated into the host bed without need for sutures in all 14 eyes. Mean duration of follow up was 11.2 months (range: 8 - 20 months). Uncorrected logMAR visual acuity improved significantly from a mean of 1.92 (range: 0.9 to 3) to 0.9 (range: 0.3 to 1.6) following FALK (p<0.05). No significant intraoperative or postoperative complications were noted in any of the cases other than partial displacement of corneal lenticule in one case which was subsequently replaced successfully. One patient had an irregular side cut on the donor lenticule and the lenticule had to be prepared again. In few patients centration with the suction cup was found to be difficult due to poor view of fixation light to the patients because of anterior corneal pathologies.

Conclusions:

FALK appears to be a safe and effective procedure for anterior stromal corneal pathologies, providing excellent improvement in visual acuity without the need for sutures or tissue ablation. This can also be considered as an excellent option for recurrent anterior corneal dystrophies having earlier undergone various corneal surgeries. FALK apparently appears to be an alternative and a better option to manage anterior corneal pathologies as compared with other modalities like PTK, limitations of which includes post-operative shifts in refraction, which can be unpredictable in degree and direction and residual stromal haze. And in addition, unlike manual or microkeratome assisted anterior lamellar keratoplasty, FALK offers advantages such as a highly reproducible fit between donor and recipient lenticules, precise pre-programmed corneal dissections at a variety of depths and orientations as well as the possibility of sutureless surgery.

Financial Interest:

NONE