This article is more than 5 years old. Information may no longer be current.
Surgeons debate similarities, differences of keratoconus, pellucid marginal degeneration
Click Here to Manage Email Alerts
ATLANTA — Two surgeons debated here whether keratoconus and pellucid marginal degeneration are variants of the same condition or distinct entities.
Robert S. Feder, MD, pointed to the clinical and histopathological similarities of the two conditions, saying the keratoconus and pellucid marginal degeneration (PMD) have similar demographics, similar appearance and similar course. Keratoconus and PMD are seen in the same eye and in same families, he said at Cornea Subspecialty Day preceding the American Academy of Ophthalmology meeting.
Similarities seen on topography and electron microscopy include areas of steepening, elevation and thinning, Dr. Feder said.
Michael W. Belin, MD, argued that, because "phenotypic expression and genotype can be very different," the two conditions should be considered distinct. Current modalities for measuring differences between the two conditions are inadequate, he said.
"We have yet to work out the genetics or biochemistry of keratoconus," Dr. Belin said. "Unless we make an attempt to separate different entities, we will never know if true differences exist."