Abstract
Purpose: :
Iris hooks are a useful adjunct to cataract surgery when the pupil is small or in phacodonesis to stabilize the capsule. The purpose of this qualitative study is to analyse four sets of new disposable iris hooks and one set of re–used disposable iris hooks with the scanning electron microscope.
Methods: :
Five separate sets of Iris hooks were examined with a scanning electron microscope. The first, third and fourth set consisted of brand new unused disposable nylon iris hooks The second set was also unused but were made of polypropylene . The fourth set consisted of disposable new iris hooks from a different source . The fifth set was from the same source as the fourth, except they had been re–used and had subsequently been cleaned and re–sterilised ready for repeat use. Different maufactures made sets one, two and three and a fourth made sets four and five.A descriptive analysis of the smoothness of the shaft, bend and tip of each hook was carried out. The presence or absence of debris was noted for Set 5.
Results: :
Set 1 hooks exhibited a smooth shaft with flattened inner aspect of the bend of the hook. The edges of the inner aspect of the angle of the hook were squared off but these were still smooth. The tip of the hook was also squared off with smooth edges. Set 2 hooks exhibited irregularities on the shaft. The inner aspect of the bend of the hook had irregular excavations on the surface. The tip of the hook had a rough surface. Set 3 were unused disposable hooks. These had a similar profile to set 1. Set 4 were brand new hooks. The shaft was smooth . The angle of the hook exhibited irregular calibre on the bend with the appearance of a crease in the material of the hook. The tip of each hook had an uneven jagged edge with sharp spurs. Set 5 were from the same source and of the same design as Set 4 but had been used previously. In addition to the irregularities present on Set 4 hooks, they also bore debris consistent with biological debris which had attached itself to the hooks, and which was still present despite cleansing and re–sterilization
Conclusions: :
Any irregularity of the hook may lead to trauma of the iris/anterior capsule and thus intra–operative complications such as a torn anterior capsule. We conclude that sets 1 and 3 disposable iris hooks provide the smoothest surface and so are the safest hooks to use intra–operatively, while sets 4 and 5 hooks have a rough profile, which also retain debris after use despite sterilization and so may increase the intra–operative complication rate.
Keywords: cataract • imaging/image analysis: clinical • pupil