Nonsurgical approaches to the management of PMD include spectacles and contact lenses. Patients present with a decrease of visual acuity in their thirties to fifties because of high and irregular astigmatism. A 1-2 mm margin of normal cornea lies between the thinning and the limbus. It is characterized by a peripheral band of thinning, usually occurring in the inferior quadrant in a crescentic fashion. Pellucid marginal degeneration (PMD) is a rare, idiopathic, bilateral, progressive noninflammatory thinning corneal disorder. CXL is a safe tool for the management of PMD, and it can help to stop the progression of this disease. No complications were recorded during or after the treatment. Patient 2’s right eye showed an improvement in his BCDVA, from 18/20 to 20/20 in 43 months, and his left eye improved from 16/20 to 18/20 in 22 months. The right eye of Patient 1 showed an improvement in her BCDVA, from 16/40 to 18/20 in 15 months, and her left eye improved from 12/20 to 18/20 in 20 months.

Patient 1 was a woman, aged 35, and Patient 2 was a man, aged 33. We have pre- and postoperatively evaluated uncorrected distance visual acuity (UDVA), best corrected distance visual acuity (BCDVA), corneal topography (Pentacam), specular microscopy, and pachymetry. Of the eyes, three had only CXL treatment and one had CXL treatment after an intrastromal corneal ring segment implantation. This study involved the retrospective analysis of 4 eyes of 2 patients with PMD that underwent CXL treatment. To report the long-term results of corneal collagen cross-linking (CXL) with riboflavin and ultraviolet-A irradiation in 4 eyes of 2 patients affected by pellucid marginal degeneration (PMD).