Capsulorhexis forceps are the surgical instrument used to remove the anterior lens capsule of the eye during cataract surgery. The tool is shaped like tweezers or tongs but with sharp tips. These tips are used to cut the surface of the eye and create a flap so that the surgeon can remove the damaged portion of the eye.
A pair of capsulorhexis forceps are generally a little more than 4 inches (110 mm) long. The sharp tips used for the incision and for grasping the lens are slightly curved and only half an inch (13 mm) from bend to tip. The forceps handle might be made of titanium or stainless steel and sterilized for multiple uses, or capsulorhexis forceps can be purchased as a single-use disposable instrument with a plastic handle.
Capsulorhexis is a form of capsulotomy in which the incision is made along the periphery of the lens in a smooth circular pattern. This is also known as the continuous curvilinear capsulorhexis (CCC). The incision into the center of the anterior capsule is created using the sharp tips of the capsulorhexis forceps. The surgeon then continues the incision either clockwise or counterclockwise around the intraocular lens. The tips of the forceps are then used to pull back a portion of tissue, creating a flap, then to grasp and place the artificial lens that will replace the cataract that is removed.
Many brands of capsulorhexis forceps include a ruler etched at the top of the instrument shaft for determining the diameter of the capsulorhexis incision. The tips might be serrated for optimal grasp of the tissue and the lens. The handle of the forceps might include ridges or indentations for a more stable grip by the surgeon.
Residents and beginner ophthalmology surgeons might find use of the capsulorhexis forceps difficult, so an alternative instrument known as a cystitome or cystotome is also available. Instead of having two sharp points for creating the incision, the cystitome is a small knife with a single curved or hooked blade. The cystitome is smaller in diameter than the capsulorhexis forceps, so there is less risk of creating too large of an incision.