Posters

Capsulorhexis without the use of automated techniques: roundness, circularity, and centricity analysis

Poster Details

First Author: L.Mavroudis GREECE

Co Author(s):    M. Banteka   A. Nikolakopoulos                 

Abstract Details

Purpose:

In modern cataract or clear lens extraction surgery, round and centered capsulorhexis covering the optic of the IOL is recognised as a significant factor in the final refractive outcome. The use of various methods of automated capsulorhexis with prominent the use of Femtosecond Laser, are lately presented as the only way in performing a circular and centered capsulorhexis. Our goal was to study the roundness, circularity and centricity of manual capsulorhexis by an experienced surgeon with the use of simple circular corneal marker and fine curved needle.

Setting:

THESSORASI- Ophthalmic Microsurgery Day Clinic Thessaloniki-Greece

Methods:

13 consecutive operations by one surgeon in one surgical day were digitally recorded. Intraoperative HD photographs were taken after capsulorhexis and after IOL insertion using the snapshot feature of the Haag Streit MIO 5 software (HS Neo, NIR optics, HD camera). Analysis was performed by masked investigator using Image J 1,51m9 (NIH, USA) in all cases with sufficient mydriasis allowing analysis. Capsulorhexis margins were marked using Freehand Tool and these of the IOL edges with Oval Tool. Roundness, circularity and centricity of the rhexis was correlated to the IOL using the analysis software on a 4K HD monitor screen.

Results:

Analysis was performed in 10 cases. In 3 cases, pupil diameter was smaller than the rhexis or the IOL optic not allowing further analysis. Mean roundness and circularity was measured at 0.97 and 1 respectively (perfect circle = 1 and total round perimeter without micro-anomalies = 1 respectively). Range 0,94 to 1 and 0,99 to 1 respectively. Centricity was estimated as the mean declination of the IOL's centre from the centre of the rhexis calculated by Image J software. Mean deviation of the center of the rhexis to the center of the IOL was 0,14mm(140microns) ranging from 0,09 to 0,19mm.

Conclusions:

The use of a simple tool can help in producing a precise capsulorhexis regarding roundness, circularity and centricity to the IOL optic. Surgeon’s attention to the marker's margins, the central reflex, the Purkinje reflexes and other anatomical features of the eye can lead to a reproducible circular and centered capsulorhexis covering the IOL optic.

Financial Disclosure:

None