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How to master MCQs
Published in Chung Nen Chua, Li Wern Voon, Siddhartha Goel, Ophthalmology Fact Fixer, 2017
Pellucid marginal degeneration is an ectatie condition characterised by thinning and flattening of the peripheral inferior cornea. This gives rise to against-the-rule astigmatism. Munson's sign is a non-specific sign and can occur in any condition which causes protrusion of the cornea. Unlike keratoconus, Fleischer's ring and Vogt's striae are not seen. Wedge resection of the thinned area can improve vision.
Ocular media
Published in Fiona Rowe, Visual Fields via the Visual Pathway, 2016
These involve deformation of corneal shape such as keratoconus, keratoglobus and pellucid marginal degeneration. Pellucid marginal degeneration is a non-inflammatory thinning of the inferior corneal periphery.
Corneal Cross-Linking: An Effective Treatment Option for Pellucid Marginal Degeneration
Published in Seminars in Ophthalmology, 2019
Pellucid marginal degeneration (PMD) is a bilateral, non-inflammatory corneal thinning disorder. The etiology and prevalence of PMD is unknown.1 This rare condition is characterized by inferior peripheral corneal thinning 1 to 3 mm from the limbus in the 4 to 8 o’clock position.2 There is a relatively normal corneal thickness adjacent to the crescentic thinned area. The well-described “crab-claw” pattern on corneal topography is not pathognomonic of PMD.1 Corneal topography, central thickness measurements, and corneal slit lamp observations must be considered together to differentiate PMD from other corneal thinning disorders.3
Rapid Resolution of Large and Non- Resolving Corneal Hydrops using a modified technique of compression sutures
Published in Seminars in Ophthalmology, 2022
Sunita Chaurasia, Muralidhar Ramappa, Somasheila Murthy
A 42-year-old female complained of sudden loss of vision in the left eye of fourdays duration. At presentation, her visual acuity was hand motions in the left eye. The left eye showed hydrops that involved the visual axis (Figure 7a). The other eye showed a peripheral thinning inferiorly and topography was suggestive of pellucid marginal degeneration (Figure 1e). Compression sutures were applied radially in the peripheral cornea. The clinical picture at 1 h after the surgery showed a marked resolution of central corneal edema (Figure 7b).
Repeated Corneal Cross-linking (CXL) in Keratoconus Progression After Primary Treatment: Updated Perspectives
Published in Seminars in Ophthalmology, 2021
Argyrios Tzamalis, Asterios Diafas, Riccardo Vinciguerra, Nikolaos Ziakas, George Kymionis
It is of note that all cases reported in the literature to require repeated-CXL refer to re-treatment after primary-CXL failure for keratoconus or post-LASIK ectasia. To the best of our knowledge, no reports of repeated-CXL have been published regarding re-treatment of pellucid marginal degeneration. Furthermore, no case of more than one re-treatment with CXL has been reported in the literature so far.