The number of intracorneal ring segments in asymmetric and central cones.

BACKGROUND: To compare the results of single versus double intracorneal ring segment (ICRS) (KeraRing) implantation in keratoconus with respect to different cone locations. METHODS: Twenty-two eyes of 18 patients with totally asymmetric cones (20-80% or 0-100% distribution along steep axis) were implanted with single ICRS (Group 1), 38 eyes of 32 patients with central or partially asymmetric cones (50-50% or 40-60% distribution along steep axis) were implanted with double ICRS (Group 2), at a depth of 80% of the site of implantation, in channels created with femtosecond laser device. All patients had uncorrected and corrected distance visual acuities (UDVA and CDVA, respectively) of ≤ 0.3 Snellen lines. RESULTS: In both groups, patients had median UDVA and CDVA gain of 3 Snellen lines (P > 0.05). Postoperative improvement in indices of vertical asymmetry and height decentration in Group 1; simulated keratometry, corneal astigmatism and anterior corneal asphericity values in Group 2 were greater (P < 0.05). A total of 10 eyes (45.5%) in Group 1 were recommended double ring implantation by the manufacturer's nomogram, but underwent single ICRS implantation and achieved visual, refractive, tomographic outcomes comparable to that in Group 2, although corneal cylindrical correction was less and final topographic astigmatism was greater. CONCLUSION: Double ICRS implantation seems to be superior in terms of keratometry, corneal astigmatism and anterior corneal asphericity improvement. Single ICRS implantation in totally asymmetric cones seems to provide satisfactory visual, refractive and tomographic results, similar to double ICRS implantation in central and partially asymmetric cones, by inducing central shift of the cone.

TNF-α Inhibitors for the Management of Intractable Corneal Melt: Report of Three Cases and Review of the Literature.

OBJECTIVE: To report three consecutive cases with noninfectious corneal melting, whose disease progression could only be halted with tumor necrosis-α (TNF-α) inhibitor infusion, with a review of the relevant literature. MATERIALS AND METHODS: Patients with toxic epidermal necrolysis, severe alkaline burn, and Sjögren syndrome had experienced severe corneal melting following penetrating keratoplasty, Boston type 1 keratoprosthesis implantation or spontaneously, respectively. Topical autologous serum eye-drops, medroxyprogesterone, and acetylcysteine formulations; frequent nonpreserved lubrication; systemic tetracyclines and vitamin-C supplements; topical and systemic steroids and steroid-sparing agents; surgical approaches including amniotic membrane transplantation, tectonic graft surgery; and tarsorraphy failed to alter the disease courses. RESULTS: Upon consultation with the rheumatology clinic, TNF-α inhibitor infliximab (Remicade; Centocor Ortho Biotech Inc, Horsham, PA) 5 mg/kg infusion was planned for each patient. After 0-, 2-, and 6-week doses, monthly infusion at the same dose was maintained for 12 months because of severe and intractable course of their diseases. Each case showed dramatic improvements in corneal melts; and sterile vitritis in the eye with Boston keratoprosthesis responded, as well. CONCLUSIONS: Inhibiting TNF-α-mediated expression of matrix metalloproteinases responsible for collagen breakdown should be considered in refractory cases, as a means of globe salvage.