Thanks to Scheimpflug tomography imaging, Fuchs’ endothelial corneal dystrophy (FECD) can be detected when it’s still in its subclinical phase—and this discovery may just change how doctors evaluate corneas.
Scheimpflug technology, which is noninvasive and requires no anesthesia, keeps the cornea and the anterior segment in focus, providing images of both the front and back surfaces of the cornea, as well as other anterior segment structures. This technology can help evaluate corneal curvature, central corneal thickness (CCT) and corneal opacities. These measurements are often used in the workup for cataract surgery or other surgical procedures, such as endothelial keratoplasty (EK).
Armed with this new evidence, researchers out of the Mayo Clinic in Minnesota’s Ophthalmology Department are recommending a reclassification of FECD.
To make this determination, the investigators evaluated 93 eyes with FECD and 74 without it, each using a slit-lamp and Scheimpflug tomography. The evaluation focused on three points: (1) loss of parallel contours within the cornea, (2) displacement of the thinnest point of the cornea and (3) focal posterior corneal surface depression.
The researchers found those features in more than 80% of the eyes suspicious for subclinical edema on Scheimpflug tomography, as well as many of the eyes that were not suspicious but later developed FECD following EK.
The researchers’ recommendations on classification protocols are as follows: “FECD corneas as having clinically definite edema (based on slit-lamp examination), subclinical edema (based on tomographic features without clinically definite edema) or no edema (no tomographic or slit-lamp features of edema).”
|Sun S, Wacker K, Baratz K, Patel S. Determining subclinical edema in Fuchs endothelial corneal dystrophy. Revised classification using Scheimpflug tomography for preoperative assessment. Ophthalmology. August 25, 2018. [Epub ahead of print].|