One of the most disheartening ways to start any phaco operation is with a peripheral tear-out of the capsulorrhexis. Unfortunately, it happens to every surgeon at some point, and it is always a challenge to manage successfully. This article describes a simple but highly effective technique for salvaging this situation. It is extremely reliable, even when the tear has gone right out into the zonules and can retrieve tears that appear impossible to get back by any other means. It should prove a useful addition to your personal library of surgical rescue maneuvers.
PREVENTION
As with all surgical complications, the universal maxim of prevention is better than cure applies here, without exception. In deference to this principle, peripheral tear-out of the rhexis can be avoided in nearly all casesjust by using an ophthalmic viscosurgical device (OVD) to keep the chamber deep throughout the rhexis. If there is significant positive pressure and a tendency for aggressive chamber collapse, this may be controlled in a number of ways: (1) by using a higher molecular-weight cohesive OVD (eg, Healon 5; Advanced Medical Optics, Inc., Santa Ana, California); (2) performing the rhexis through a sideport using a needle cystotome; (3) or using an infusion syringe of OVD, held in the nondominant hand through the sideport, while using forceps for the rhexis in the other hand. The other principle of prevention is early recognition of a threatening situation that is still retrievable before it develops into a full-blown complication. As soon as there is even the slightest hint of the rhexis migrating out peripherally, you should stop and refill the chamber to flatten the anterior lens surface. This is usually sufficient to remain in control of the tear.
SURGICAL TECHNIQUE
The first step in the effective management of any complication is to recognize that it has happened. Stop all activity and calmly assess the situation. With a peripheral tear-out, the principle aim is to prevent posterior propagation of the tear around the equator and through the posterior lens capsule. This actually happens surprisingly rarely in practice, possibly due to the criss-crossed insertions of the zonules, offering resistance and blocking the tear. The next step is to completely fill the chamber with an OVD before attempting to the rescue the rhexis.
The tear now needs to be redirected centrally back to its original path. The most efficient way of doing this is to unfold the anterior capsule flap and lie it flat against the lens cortex. Using forceps, the trick is to then hold the flap near the root of the tear and pull it backward circumferentially in the direction from where it came, applying the force in the plane of the capsule, to put it under tension. While holding the flattened flap under tension, the traction should now be directed more centrally to initiate the retrieving tear. Resolution of the applied tangential and central vector forces redirects the tear predictably toward the center of the capsule. The flap may now be refolded, and the rhexis is safely continued.
AVOID WRAP-AROUND TEAR
In the rare event that the capsule will not tear easily and the entire lens is being pulled centrally, the rescue maneuver should be abandoned to avoid a wrap-around capsule tear. Alternative recovery techniques (ie, completing the capsulotomy from the opposite direction, making a relieving cut in the flap edge and continuing in the same direction, or resorting to a can-opener technique) are appropriate.
The key points to emphasise in the rhexis rescue technique are:
•Completely fill the chamber with viscoelastic before any attempt at retrieval.
•If necessary, make a second stab incision at the position that allows the optimal angle of approach for applying traction.
•Unfold the flap of the anterior capsule, and flatten it against the lens (instrumental or viscomanipulation).
•If visibility of the capsule edge is compromised, have a low threshold for using trypan blue to visualize the edges of the tear.
•Refill the chamber with viscoelastic immediately before attempting retrieval.
•Use only rhexis forceps: It should not be attempted with a needle cystotome, because the directional control is inadequate, and the needle tip is likely to tear the flap.
•Grasp the flap as near to the root of the tear as practically possible.
•Apply traction in the horizontal plane of the capsule, and do not lift it forward.
The initial pull should be circumferentially backward, and while holding the flap in tension, pull more centrally to initiate the tear, which will then propagate toward the center.
The big mystery is how much force may be safely applied. The answer is: as much as you feel safe using. This gets clearer as you become more experienced. If in doubt, abandon the technique and use an alternative recovery technique.
Brian C. Little, MA, DO, FRCS, FRCOphth, is an Ophthalmologist at the Royal Free Hospital, NHS Trust, in London. Dr. Little is a member of the CRST Europe Editorial Board. He states that he has no financial interest in the products or companies mentioned. He may be reached at eye.surgeon@mac.com.
Up Front | Mar 2007
Rescuing a Capsulorrhexis Tear-Out
I have developed an effective and highly useful technique that allows completion of the rhexis in nearly all cases.
Brian C. Little, MA, DO, FRCS, FRCOphth