Posters

Efficiency and result quality of different nucleus fragmentation patterns in femtosecond laser-assisted cataract surgery

Poster Details

First Author: P.Hoffmann GERMANY

Co Author(s):    M. Abraham                    

Abstract Details

Purpose:

To evaluate the effect of two different femtosecondlaser nucleus fragmentation strategies on ultrasound energy levels and corneal trauma.

Setting:

Augen- und Laserklinik Castrop-Rauxel, Deutschland / Germany

Methods:

Retrospectively, QM data of 140 surgical procedures were reviewed. In group 1 (n=56), a cube-like softening pattern with 300-500 (373 ± 57) µm edge length without radial elements was performed. In group 2 (n = 84), a segmentation of the nucleus into 4-8 (5.5 ± 1.0) pieces was performed with radial cuts. All procedures were performed by a single surgeon using the same phaco machine (Alcon Centurion) and needle through a 2.2 mm posterior-limbal temporal incision. As a measure of corneal trauma, the swelling on day 1 and endothelial cell loss after 4 weeks were recorded.

Results:

Median phaco time was 0.41 (0.0–6.4) s in group 1 and 1.47 (0.0–13.4) s in group 2 (Mann-Whitney P<0.001). As a comparison, the same surgeon used 2.40 (0.0–14.8) s in manual quick chop phaco with the same machine. Median corneal swelling was 34 µm in group 1 and 24 µm in group 2 (Mann-Whitney P>0.1). Median endothelial cell loss was 90 cells/mm2 in group 1 and 89 cells/mm2 in group 2 (Mann-Whitney P>0.1).

Conclusions:

Cube shaped fragmentation effectively softens the nucleus. In a typical eye, 83% of phaco energy can be saved as opposed to only 40% with a segmentation pattern. In nuclei up to LOCS NO3, a disposable aspiration device may be used instead of the phaco handpiece. However, tight fragmentation will impair visibility, flatten the anterior chamber, increase the total amount of energy and potentially generates more fragments circulating through the anterior chamber. We could not confirm an advantage in corneal trauma over the less energy-intensive segmentation pattern. Every surgeon should decide which laser strategy suits his patients better.

Financial Disclosure:

NONE