Update on pellucid marginal degeneration

To review recent developments (2014-2024) in the diagnosis and treatment of pellucid marginal degeneration (PMD), focusing on advances in corneal imaging technologies, biomechanical assessments, and the effectiveness of current contact lens treatments and surgical techniques. Additionally, to discuss the role of PMD in cataract surgery and the use of toric intraocular lenses (IOLs).

Structured search of PubMed, Scopus, and Embase (Nov 2024; Jan 2014-present) using PMD-related keywords/MeSH. After dual independent screening of 129 citations using predefined inclusion/exclusion criteria, 50 articles met eligibility and were included.

Recent technologies enable better assessment of corneal curvature and pachymetry relationships, aiding differentiation of PMD from other ectatic diseases. Advances in biomechanical assessments have improved early detection and diagnostic precision. Most patients can be managed conservatively with new types of rigid contact lenses. Modified corneal cross-linking (CXL) protocols show promise in stabilizing the disease. Lamellar transplants offer visual outcomes comparable to penetrating keratoplasty with fewer complications. Wedge resection shows promising outcomes, but larger studies with long-term follow-up are still required. In cataract surgery, toric IOLs may provide effective astigmatism correction in selected PMD patients.

The diagnosis and treatment of PMD have significantly evolved in the last decade. Improved imaging and biomechanical assessments aid in accurate diagnosis. Contact lenses and lamellar surgery are mainstay treatments. Future clinical studies should focus on the CXL protocols.