Induction of neoplasia after deep anterior lamellar keratoplasty in a CXL-treated cornea.

PURPOSE: Corneal collagen crosslinking (CXL) with ultraviolet-A energy plus riboflavin has become a ubiquitous treatment in early keratoconus, although its long-term safety is unknown. We describe severe sequelae in a CXL-treated patient after he underwent a standard deep anterior lamellar keratoplasty procedure. METHODS: In April 2009, a healthy 49-year-old male patient (R.H.) underwent bilateral CXL according to the Dresden protocol for progressive keratoconus stage 3. The best-corrected visual acuity did not improve over 20/100 within a postoperative period of 2 years, and contact lenses were not tolerated. Consequently, a unilateral deep anterior lamellar keratoplasty was performed, to transplant an 8-mm fully epithelialized button onto an 8-mm bed with a bared Descemet membrane (surgeon: J.H.K.). RESULTS: The postoperative healing course was unusually disturbed. Sutures pulled through the recipient tissue, which required suture replacement. Portions of the epithelium sloughed off repeatedly, and bulky regrowth displayed no attachment to the Bowman membrane. Within the first weeks, the transplant became cloudy. Two biopsies were removed from the limbus area and submitted to independent histopathological laboratories, both of which diagnosed the condition as epithelial neoplasia. Pathology tests indicated conjunctival intraepithelial neoplasia, the preliminary stage of invasive squamous cell carcinoma, in the keratocyte-voided bed of the recipient. CONCLUSIONS: This case suggests that CXL might hamper the ocular healing process and, combined with subsequent corneal surgery, could potentially initiate neoplasia. Further investigation is warranted to determine the safety of the combination of ultraviolet-A/riboflavin treatment and subsequent corneal tissue transplantation.

Circular keratotomy to reduce astigmatism and improve vision in stage I and II keratoconus.

PURPOSE: To report the use of circular keratotomy in eyes with stage I and II keratoconus to reduce astigmatism. METHODS: A retrospective analysis was performed of all eyes operated from 1993 to 2006 by one surgeon using circular keratotomy for stage I and II keratoconus. Results were evaluated for reduction of corneal astigmatism, refractive stability, and change in best spectacle-corrected visual acuity (BSCVA). RESULTS: Forty-six eyes in 36 patients were evaluated. Corneal (keratometric) astigmatism and refractive astigmatism were significantly reduced, particularly in eyes with preoperative astigmatism > or = 2.00 diopters (D). Preoperative astigmatism correlated with reduction of astigmatism (R = 0.81). Astigmatism stabilized after 1 year in 64% of 28 eyes that were seen both within the first year after surgery and then at some time point > or = 2 years after surgery. In this group, astigmatism changed < or = 2.00 D in 94% of eyes between 1-year follow-up and the last examination. Mean BSCVA improved from 20/44 to 20/33 (P < .01), with 20 (43%) of 46 eyes gaining 2 lines or more, 22 (48%) of 46 eyes changing by less than 2 lines, and 4 (9%) of 46 eyes having a worse BSCVA at the last examination compared with preoperatively. CONCLUSIONS: Circular keratotomy provides significant reduction in astigmatism, improved BSCVA, and stabilization of astigmatic changes in most eyes, although some eyes show limited benefit. Eyes with higher preoperative astigmatism appear to be more likely to benefit from the procedure than those with lower preoperative astigmatism. Circular keratotomy also resulted in reasonable clinical results for the treatment of stage I and II keratoconus.

Intrastromal corneal ring in penetrating keratoplasty: evidence-based update 4 years after implantation.

PURPOSE: To report the clinical outcomes of an intrastromal corneal ring (ISCR) used in penetrating keratoplasty (PKP) that was designed to decrease postoperative corneal astigmatism, stabilize refraction, accelerate healing, and possibly reduce immune reactions. MATERIALS AND METHODS: An 8 mm cobalt-titanium-molybdenum alloy ring was sutured into the PKP wounds. A prospective study compared the outcomes of PKP in 179 consecutive cases with a ring (Group 1) and 101 consecutive patients without a ring (Group 2). The ring was used in different types of endoepithelial degeneration as well as in keratoconus stage IV. Patients with macular pathology were included. RESULTS: The mean age of Group 1 patients was 67 years (range 9 to 96 years). Postoperative best corrected visual acuity after 1 year was almost identical in both groups (20/42 in Group 1 and 20/45 in Group 2) as were the cylinder values (Group 1, 2.64 diopters [D] +/- 1.44 (SD) versus Group 2, 2.83 +/- 1.52 D). There were 2 immune reactions in group I as compared to 6 (1.2% vs 7%, P value 0.02) in group II within 4 years of the procedure. Evaluation was performed by the Kaplan-Meier method. CONCLUSION: Advantages of the ISCR were observed outside the targeted goals of improving the amount of astigmatism and maintaining refractive stability. Best corrected visual acuity and cylinder development were similar in Groups 1 and 2, whereas, there was a highly reduced immune rejection rate. The ring also appeared to act as a barrier to superficial vessels.