Posters

Think hexagon instead of square for pupil expanders

Poster Details

First Author: S.Bhattacharjee INDIA

Co Author(s):                        

Abstract Details

Purpose:

To compare the efficacy and safety of square versus hexagon shaped pupil expanders

Setting:

Nayan Eye Centre, Kolkata, India

Methods:

6.5 mm Square or hexagon shaped new design pupil expanders used alternately in 116 consecutive eyes over 30 months. The 0.1 mm thin single plane flexible device has notches at the corners and flanges at the sides. Alternate flanges tucked under the iris with 23 gauge forceps. Horizontal WTW and expanded pupil size were measured. Videos and surgical notes were analyzed for ease of insertion, engagement and removal.

Results:

Horizontal WTW 11.5 +/- 1.0 mm. Expanded pupil square 5.2 mm +/- 0.2 mm SD and hexagon 5.5 +/- 0.2 SD. Square device took rhomboid shape and could not be inserted completely into the anterior chamber in single pass if WTW was less than or equal to 11.5 mm while hexagon was inserted completely. Anterior chamber manipulations were difficult and constrained with square compared to the hexagon due to corners pushing against the angle.

Conclusions:

Size for size, the Hexagon design is safer and efficacious compared to a Square design Pupil Expander. This can be conclusively established by simple geometrical diagrams. The square pupil formed by four iris hooks has probably prevented us from thinking beyond the square shape for a pupil expander.

Financial Disclosure:

gains financially from product or procedure presented