Malyugin ring

This is a small spring-like device used during cataract surgery to help dilate the pupil.  Small pupils make cataract surgery difficult, as the procedure involves vacuuming out the cataract “through” the pupil.  Some people have naturally small pupils (the black hole in the middle of the iris) and don’t dilate well. Poor dilation may be genetic or occur from atrophy of the iris muscle that occurs with age. The smaller the pupil, the more difficult it is to work on the cataract.  In these cases, many surgeons will use a Malyugin ring. It is a small spring made of plastic that is temporarily injected into the eye to keep the pupil wide open (with a mild amount of iris stretching) until the surgery is completed. At the end of the surgery, the ring is removed to allow the pupil to constrict back to its normal size. This is a simple yet elegant technique that is also useful in cases of floppy iris syndrome as the ring keeps the iris from moving around during surgery.