“Central and Peripheral Corneal Iron Deposits

after Implantation of the KAMRA™

(AcuFocus Corneal Inlay)“

G.Nix1, O.Seyeddain1, W.Riha1, M.Hohensinn1, G.Grabner1, E. Messmer2,

A.K.Dexl1 

1 University Eye Clinic, Paracelsus Medical University, Salzburg, Austria

2 Department of Ophthalmology, Ludwig-Maximilian-University, Munich,

Germany

Methods

We evaluated 32 eyes undergoing KAMRA™

implantation. The intracorneal inlay was implanted

by one surgeon (G.G.) in the non-dominant eye by

creating a superior hinged flap with the Intralase

60kHz femtosecond laser and placing it over the line

of sight intrastromally.

Corneal iron deposits were analyzed with slit-lamp

and in vivo confocal microscopy with regard to the

postoperative time interval and corneal topography.

Purpose

To describe central and peripheral corneal iron

deposits after KAMRA™ implantation in naturally

emmetropic presbyopic patients.

Results

Seventeen (53%) of 32 eyes developed brown-colored corneal iron

deposits of variable density in the epithelium. One had deposits in the

center only (6.0%); eight at the periphery of the inlay (47.0%); and eight

over both areas (47.0%). These are best observed in blue light. On

confocal microscopy clusters of Iron deposits were located very near to

Bowman´s membrane and single dots of iron deposits were found in the

remaining part of the epithelium. The median interval between KAMRA™

implantation and the first diagnosis of corneal iron deposits was 22.2

months. Location of this iron deposits correlated positively with the

characteristic albeit minimal changes of corneal topography after

KAMRA™ implantation.

Conclusions:

This is the first report of the appearance of corneal iron deposits following KAMRA™

implantation in 17 patients. They have no noticeable influence on final visual acuity, either

distance or near, corrected or uncorrected. As reported for other corneal iron lines and

dots (e.g. the Hudson-Stähli-line, iron deposits with keratoconus, the Fleischer ring,

following trabeculectomy, radial keratotomy, epikeratophakia, LASIK and others) the

authors suggest that alterations in tear film thickness, possibly its composition and

corneal epithelial basal cell storage - as a result of changes of corneal topography -

constitute the contributory factor for these specific iron depositions.

S A L K

References:

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Fig. 1: HRT II with Rostock Cornea Module

Fig. 3: Iron deposits 24 month after implantation and corresponding corneal topography

Fig. 4: Central and peripheral iron deposits 24 month after implantation

Fig. 5: Central and peripheral iron deposits 18 month after implantation

Fig. 2: Confocal image: Iron deposits in Epithelium

Author Disclosure Block:

G.Nix (F), W.Riha (F), M.Hohensinn (F), O.Seyeddain

(F), A.Dexl (F) and G.Grabner (F).

Clinical Study Payments by Acufocus Inc., Irvine,

California