38.4.2 No IOL Implantation

• A (highly myopic) globe that is roughly emmetropic without implantation.17

• An eye that has lost the potential for both central and peripheral vision.

• It is impossible to predict whether the implanted silicone oil can be removed.18

38.4.3 Delayed IOL Implantation19

•The surgeon is uncertain preoperatively whether the anatomical situation in the posterior segment will justify the implantation.

•Extensive manipulations are necessary in the periphery.

–No visual interference from the parallaxis around the IOL edge.

–The IOL may get subluxated.

38.4.4 Secondary IOL Implantation20

•The surgeon is not certain that visual improvement can be expected even if the best anatomical outcome will have been achieved.

•It was impossible to preoperatively predict the power of the IOL.

•There is a very high risk of postoperative PVR development.

38.5Capsule Removal

In some cases, it is best to remove the lens capsules.21

Q&A

Q Is the removal of the lens capsules not a controversial issue?

AFor some ophthalmologists it is. My experience, however, is that it is extremely beneficial in many cases, even if the indication is rarely absolute. The option to implant an iris-claw IOL further lowered the bar in choosing capsule removal.

17The old adage that “the eye needs to be compartmentalized” is not true anymore.

18Once the question is definitely answered, an IOL may be implanted secondarily.

19Defined here as an IOL that is placed after the PPV has been completed, but in the same surgical session.

20Defined here as an IOL that is implanted in a separate procedure in the future.

21Remember, the default goal is not the implantation of an IOL in the bag. Instead, the aim is to restore the rest of the globe anatomy to the fullest possible. Long-term thinking is needed, which is why the capsules may have to be sacrificed or the IOL implantation foregone.

38.5.1 Indications

•A lens that is subluxated, whether spontaneously or due to trauma.

•Systemic conditions in which (sub)luxation is expected.22

•Weak zonules that may not hold the bag/IOL securely.

•Not enough posterior capsule is left to securely hold the IOL.

•Severe postoperative inflammation is expected with consequent synechiae development.

•High risk of postoperative PVR development.

38.5.2 Surgical Technique

•Complete the lens removal.

•Whichever capsule is present, make a central capsulectomy with the probe.

•Take a crocodile forceps,23 grab the capsule, and do one of the following.

–In young patients,24 insert the probe through the other working sclerotomy, and pull the capsule with the forceps in one direction; rather than tear the zonules, use the probe to sever them. Repeat the process on the opposite side of the eye after switching instruments (see Fig. 38.3).

–In older patients simply pull the capsule, and use your other hand to “spaghetti” the capsule so that the tension on the zonules is distributed over a larger area, delaying the moment when the capsule tears. Repeated grabbings, probably from both sclerotomies, are probably necessary.

•To be on the safe side, inspect the periphery with scleral indentation, and (at least consider to) perform endolaser cerclage.

Fig. 38.3 Capsule removal in a young patient. Simply pulling on the zonules does result in their separation from the ciliary processes, but the risk of the traction force getting transmitted to the anterior retina is high. Use of the probe to cut, rather than manually tear, the zonules is an option that eliminates the risk

22Marfan syndrome, pseudoexfoliation, homocystinuria etc.

23So that you can grab as large a piece of the capsule as possible.

24Up to ~30 years; extra caution is in order, due to the strength of the zonules. The risk is that the ciliary processes may be damaged as the pull force is transmitted to them.

38.6.2 Surgical Technique

•Remove the lens capsules.

•Consider creating a small iridectomy with the probe.27

•Prepare a small, temporal paracentesis so that a long and thin spatula can later be inserted.

•Open the conjunctiva and prepare the scleral incision.

–Length: 6 mm for the regular and 3 mm for the foldable version.

–Location: scleral tunnel or limbal. Use diathermy around the incision site to prevent blood seeping into the AC.

•Inject viscoelastic in the AC to protect the endothelium.

•Flip the lens so that its convex surface faces the vitreous cavity (see Fig. 38.5); insert it into the AC, rotate the lens 90°, and then use forceps to slide it behind the iris.

•Insert the spatula. Ensure that the IOL optic maintains its desired position,28 tilt the distal (nasal) haptics upward, and simultaneously push the iris in-between the haptics; the iris-captures are at the ~3 and 9 o’clock positions.

–Gently pull on the lens to make sure that it is securely in place; confirm that the optic is still at its desired position.

–Pull the spatula out halfway so that you can repeat the procedure on the temporal side.

–Again check that the IOL is firmly attached to the iris at both locations.

•Suture the limbal (scleral) wound.

•Irrigate the vitreous cavity in case a small hemorrhage has occurred.29

Fig. 38.5 The “anatomy” of the iris-claw IOL. The image shows the lens from the side; the convex surface should face the vitreous cavity if the IOL is implanted behind the iris

27Not all surgeons do this; pupillary-block glaucoma is indeed rare. The iridectomy is, however, highly recommended if the flat surface of the lens is against the iris.

28The IOL is well centered; it is rather easy to inadvertently move the lens in the horizontal plane as the claws are to be fixed to the iris.

29It is not uncommon that the VH occurs postoperatively, but it is almost always small and requires no intervention.