Purpose: To determine the efficacy of simultaneous peripheral crescentic lamellar keratoplasty (LK) and central penetrating keratoplasty (PK) for advanced pellucid marginal degeneration (PMD).
Design: Retrospective, noncomparative, interventional case series.
Participants: Five patients with advanced PMD.
Method: Simultaneous peripheral crescentic LK and central PK followed by selective suture removal and astigmatic keratotomy in the postoperative period.
Main outcome measures: These included interval of time required for visual rehabilitation, best spectacle-corrected visual acuity achieved, and amount of corneal astigmatism, as measured by videokeratography. Measuring the change in corneal astigmatism by videokeratography over the subsequent follow-up period after spectacle correction had been prescribed assessed stability of the achieved refraction.
Results: Visual acuity results were 20/40 in three eyes, 20/80 in one eye, and 20/400 in one eye. The latter two had decreased acuity from posterior subcapsular cataract formation, which may have been caused by topical steroid use. The time required for visual rehabilitation ranged from 5.13 to 10.93 (mean, 9.92) months, and the amount of corneal astigmatism at the end of this period ranged from 0.3 diopters (D) to 5.3 D. A tendency for an increase in "with the rule astigmatism" after the rehabilitation period was noted. Two patients had elevations of intraocular pressure that responded to reduction in topical steroid dose.
Conclusions: The short-term results with this technique are excellent in that it provides early and stable visual rehabilitation in patients with advanced PMD. Low to moderate levels of postkeratoplasty astigmatism were achieved in all the eyes treated. The usual tendency of an increase in "against the rule astigmatism" that occurs when PK alone is done for PMD was eliminated.