Two-step strategy-conjunctival flap covering surgery combined with secondary deep anterior lamellar keratoplasty for the treatment of high-risk fungal keratitis

Abstract

Aim: To investigate whether the two-step strategy [conjunctival flap covering surgery (CFCS) combined with secondary deep anterior lamellar keratoplasty (DALK)] is effective for patients with high-risk fungal keratitis (FK).

Methods: In this noncomparative, retrospective case series, 10 subjects (6 males, 4 females) with a mean age of 56.5±7.1 (range 47-72)y with high-risk FK undergone the two-step strategy were included. Reported outcome measures were healing of the corneal ulcer, recurrence of FK, reject reaction, improvement in best corrected visual acuity (BCVA) and relevant complications.

Results: The average diameter of corneal infiltrates was 7.50±0.39 mm, ranging from 6.94 to 8.13 mm. The mean depth of corneal infiltrates was 422.4±77.1 µm, ranging from 350 to 535 µm. The mean corneal thickness was 597.4±117.3 µm, ranging from 458 to 851 µm. Hypopyon and endothelial plaques were presented in all patients. The period between the two steps was 3.65±0.9 (ranging from 3 to 5)mo. The graft diameter was 7.75±0.39 mm. At the last follow-up (average 9.25±3.39, ranging from 5.5 to 17mo), no fungal recurrence or graft rejection appeared, and all patients showed improvement of BCVA. One patient suffered from liver function impairment due to oral voriconazole for 4wk and recovered spontaneously after 1wk of drug withdrawal.

Conclusion: The two-step strategy is safe and effective in the treatment of high-risk FK by transforming intentional therapeutic penetrating keratoplasty during acute infection to later optical DALK. It is a practical strategy, especially in areas lacking fresh donor corneas and eye bank services.

Keywords: conjunctival flap; deep anterior lamellar keratoplasty; fungal keratitis; high-risk; two-step strategy.

Figure 1. Video images of surgical procedure

A: The FK patient had a raised central corneal lesion; B: The necrotic tissue was removed with a blade; C: Voriconazole solution 100 µg/0.1 mL was injected to corneal stromal around the infiltrate; D: The bipedicle CF was sutured with a 10-0 nylon to the cornea over the ulcer; E: The cornea became stable with a leucoma and superficial vascular membrane; F: Air was injected into the mid-stroma and a big bubble was formed extending to the border (white arrows); G: The residual cornea was smooth with no obvious opacification; H: Corneal graft was sutured interruptedly with 10-0 nylon. FK: Fungal keratitis; CF: Conjunctival flap.

Figure 2. Case 1, slit-lamp photographs and examinations of a 55-year-old female with central corneal ulcer

A: The patient presented with a 7.2 mm central corneal ulcer, 1 mm hypopyon in her left eye; B: Fungal hyphae were detected under IVCM and the cultured pathogen was Aspergillus specie (insert); C: The depth of infiltrate was 535 µm; D: The cornea became stable 3mo postoperatively; E, F: The central cornea remained mild opacity 10mo after DALK with 95 µm residual host cornea. IVCM: In vivo confocal microscopy; DALK: Deep anterior lamellar keratoplasty.

Figure 3. Case 6, photographs of a 72-year-old FK patient after plant-related trauma

A: A large fungal ulcer with 2 mm hypopyon was observed by slit-lamp examination; B: Hyphae were detected and the cultured pathogen was Fusarium specie (insert); C: CFCS was performed successfully; D: A stable ocular surface was obtained 3mo after CFCS; E: A transparent cornea was reconstructed 3mo after DALK; F: The residual host cornea was 38 µm. FK: Fungal keratitis; CFCS: Conjunctival flap covering surgery; DALK: Deep anterior lamellar keratoplasty.