B-Hex Pupil Expander - Entry And Exit Incisions Sizes

To determine the smallest clear corneal incisions that could be used to safely deploy and remove the novel B-HEX Pupil Expander.

Private Practice, Nayan Eye Centre, Kolkata, India.

The 0.075 mm or 75 micron thin, single plane, 6.5 mm, hexagonal, B-HEX Pupil Expanders were used in 76 consecutive eyes over 24 months. The resiliently flexible device with notches and flanges is preloaded in a transparent carrier with an ergonomic handle which delivers the device sterile at the incision. It is introduced into the eye and removed from the eye using the recommended B-HEX 23G Forceps. Incision size for insertion & removal was progressively reduced from 2.6 mm to 0.9 mm in consecutive groups of cases. The ease of passage of the device, deformity caused and resultant reduction in performance were noted. The injury to the cornea or iris were also noted.

There was no difficulty in insertion or distortion of the device when incision size was greater than 1.9 mm. For incision sizes 1.9 mm to 1.5 mm, there were mild distortions in the flanges with recovery. For incisions smaller than 1.5 mm, the distortions in shape of the flanges reduced the performance of the pupil expander and there was injury to the sides of the corneal incision. For removal, incision sizes up to 0.9 mm could be used safely.

For insertion, the forceps jaws and the flange traversed the incision together. The flanges did not regain shape fully for incisions smaller than 1.5 mm and this affected performance. For removal, 0.9 mm incisions could be used as the forceps jaws and the flange traversed the incision consecutively and flange distortions were irrelevant.