October 02, 2022
1 min read
Shimazaki J. Pellucid marginal corneal degeneration. Presented at: American Academy of Ophthalmology meeting; Sept. 30-Oct. 3, 2022; Chicago.
Shimazaki reports no relevant financial disclosures.
CHICAGO — Pellucid marginal corneal degeneration is a rare disease, but early diagnosis is necessary to ensure patients’ quality of life, according to a speaker.
“The pathogenesis of PMD remains unclear, and no genetic cause has been found,” Jun Shimazaki, MD, PhD, said at Cornea Subspecialty Day at the American Academy of Ophthalmology meeting. “There is no detailed epidemiological data, and unilateral cases constitute 25% of all patients.”
Proper management of pellucid marginal corneal degeneration (PMD) is important, Shimazaki said, and visual disturbances may develop later and continue to progress. Collagen cross-linking may be useful for halting disease progression, as well as the use of an intracorneal ring segment or corneal transplantation. Crescentic lamellar keratoplasty and crescentic wedge excision can also be considered, he said.
Contact lenses, including gas-permeable hard, hybrid or scleral lenses, are the most common form of medical management for PMD, Shimazaki said. Glasses may also be used, but refractive surgery should be avoided. Unlike keratoconus, stromal striae and iron ring are not seen in PMD cases, and physicians should be aware that acute hydrops may occur in patients with the disease.
“Mild cases of PMD are difficult to detect with slit lamp examination alone,” Shimazaki said.
PMD is most commonly misdiagnosed as inferior keratoconus.
“Corneal topography is a powerful tool for the early diagnosis of PMD,” he said.