Posters

Polarimetric interferometry: a new technique for assessment of corneal stromal lamellae orientation with a potential application in endothelial keratoplasty

Poster Details

First Author: A.Iovieno ITALY

Co Author(s):    E. Lipari   L. Fontana           

Abstract Details

Purpose:

To analyze corneal stromal lamellae orientation in normal subjects and in patients with corneal affections using a novel polarimetric interferometry device (Lumaxis®, Phronema srl, Italy) and to assess whether coupling of stromal lamellae alignment in donor and recipient could have an effect on visual outcomes following endothelial keratoplasty.

Setting:

Single center (Department of Ophthalmology, Arcispedale Santa Maria Nuova, Reggio Emilia, Italy).

Methods:

50 healthy control subjects and 50 patients with various corneal stromal diseases (edema, scarring, neovascularisation, etc) were included in the study. All patients were imaged using the Lumaxis polarimetric interferometer and slit lamp photography. The Lumaxis interferometer produces an orientation image of the posterior stromal lamellae by illuminating the cornea in phase-light polarization angle. In addition, 10 patients with endothelial disease underwent endothelial keratoplasty with a standard technique by a single surgeon (AI). In 5 of these patients, the donor disk was positioned so that the orientation of the donor stromal lamellae would match the one of the recipient. In the remaining 5 (controls), the lamellar orientation of donor and recipient was purposely mismatched. Visual outcomes (uncorrected and corrected distance visual acuity) were analyzed at 6 months post-operatively.

Results:

In healthy subjects, a cross-like orientation of stromal lamellae was observed, which was consistent with previous X-rays and second harmonic generations studies. The polarization axis was found to be at 90 degrees in the majority of patients. An orientation image could not be obtained in patients with corneal disease affecting stromal clarity. In the 5 patients who underwent DSAEK with lamellar orientation matching better visual acuity was detected at the 6 months post-operative timepoint compared to controls.

Conclusions:

Corneal stromal lamellae orientation can be efficiently assessed and displayed as a user-friendly cross-like image by the Lumaxis polarimetric interferometer. Stromal lamellae imaging could have implications in corneal diagnostics as well as lamellar keratoplasty. FINANCIAL INTEREST: One of more of the authors... gains financially from product or procedure presented