Selective INTACS implantation combined with corneal collagen cross linking allows for effective rehabilitation of uncorrected visual acuity
Guide to the Successful Surgical Correction of Post LASIK Ectasia
The development of ectasia following laser vision correction continues to represents the most dreaded complication. Weakened post surgical corneal structural integrity can result in marked alteration in corneal topography and with it irregular astigmatism and loss of best-corrected visual acuity.
Fortunately, improvements in the methodology of pre operative evaluation of prospective patients and a better understanding of the limits of the safe application of excimer laser ablation have greatly reduced the incidence of this dreaded complication. Although these cases are now extremely rare, it is incumbent on all refractive surgeons to have a strategy towards correcting post-operative ectasia. Post LASIK ectasia is now a very manageable problem with the real opportunity for stabilization of the weakened cornea and improvement of vision as demonstrated in the following case that we managed very recently at our clinic.
Our patient is a 47 year-old male who had standard LASIK surgery performed with mechanical microkeratome in 1999 for high myopia. His preoperative best-corrected acuity was 20/15 OD with -8.00-0.75x 150 and 20/15 OS -9.50-0.25×20. Pre operative central ultrasonic pachymetry was 539 microns OD and 525 microns OS and placido ring topography was unremarkable. Surgery was performed resulting in a satisfactory uncorrected acuity of 20/20 OD and 20/25 OS, however, at an examination with his local optometrist 4 years later the patient complained of reduced uncorrected acuity in the left eye documented as 20/200, correctable to 20/30 with -1.25-4.00×65. On referral to our clinic Pentacam tomography revealed inferior steepening in a pattern diagnostic of evolving ectasia OS>OD (Figure 1).
After a full and detailed review of findings with the patient surgical intervention was recommended consisting of Intacs intrastromal rings to improve corneal topography combined with collagen corneal cross-linking to halt any further progression of the condition.
On 3/21/14 a single 0.45 Intacs ring was implanted at 75% depth in the area corresponding to the ectasia making use of the Intralase laser with incisional entrance at axis 340 degrees corresponding to the steepest corneal meridian. Corneal collagen crosslinking was then applied OU making use of standard epithelium off technique. The procedure was uncomplicated and well tolerated.
On this patient’s last postoperative examination on 12/23/14 uncorrected acuity was 20/30 OD correctable to 20/20 with -0.50-1.50×100 and 20/30 OS correctable to 20/20 with plano-1.00×45. Pentacam tomography demonstrated marked improvement in corneal morphology.