“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
SALK
2 Department of Ophthalmology, Ludwig-Maximilian-University, Munich,
Germany
Purpose
To describe central and peripheral corneal iron
deposits after KAMRA™ implantation in naturally
emmetropic presbyopic patients.
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.
Fig. 3: Iron deposits 24 month after implantation and corresponding corneal topography
Corneal iron deposits were analyzed with slit-lamp
and in vivo confocal microscopy with regard to the
postoperative time interval and corneal topography.
Fig. 1: HRT II with Rostock Cornea Module
Fig. 4: Central and peripheral iron deposits
24 month after implantation
Fig. 5: Central and peripheral iron deposits
18 month after 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.
Fig. 2: Confocal image: Iron deposits in
Epithelium
References:
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.
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
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