Cataract surgeons are used to chopping and cracking a lens's nucleus to facilitate removal. It's what we are most comfortable with, since we do it practically every surgery day. Divide and conquer, phaco chop—whatever your flavor—these techniques require a nucleus that has some amount of hardness to it. If we attempt to separate a nucleus that has a very soft nature, however, we can't use the techniques with which we are so familiar. Removal of the softer lens poses special challenges for the surgeon, and in this article, I'm going to share some tips that have kept me out of trouble with eyes like this.

Why Worry About the Soft Lens?
Ophthalmologists are going to see more soft lenses slated for removal in the next few years as we become more proficient in refractive lens surgery beyond cataract surgery. Younger patients will be coming to us for lens exchange strictly for refractive purposes and not because of visual disability from cataract. In fact, I believe refractive lens surgery will eventually outpace contact lenses and LASIK because of its permanence and reliability. Patients who present for this surgery will be in their 30s and 40s and offer spongier lenses to the surgeon, and not the hard lenses typical of the patients in their 60s and 70s, and knowing how to deal with these types of lenses will be crucial.

As wavefront measurements mature, I think refractive lensectomies will become even more popular. There's a good chance that wavefront is going to teach us that once a person is over the age of 50, a lot of the aberrations in the eye come from the lens and not the cornea. Refractive surgeons will have to reconsider doing custom ablation on the corneal surface when the real problem is in the lens, and those aberrations will get worse. In this case, the best solution may be a lens procedure rather than a corneal one. Pharmacia's Tecnis lens, designed to help reduce spherical aberration, is an example of this concept.

Similarly, I believe we'll be able to reduce problems with presbyopia intraocularly rather than on the corneal surface. As the aging baby boomers grow unhappy with their reading glasses, particularly if they are hyperopic, we're going to be seeing the lens replacement procedure become more popular. This shift will certainly occur in practices geared toward presbyopic correction, and with ophthalmologists who are early adopters of new methods.

At this time, however, most patients are undergoing lens implantation for vision issues due to cataracts. Of these patients, the ones with the softer lenses are those with posterior subcapsular cataracts, or younger patients with dense cortical opacity that prevents them from seeing well. Extraction of the softer lens has a different feel to it, and many surgeons don't see enough of it to be able to get into a comfort zone. The procedure is a little less predictable because it's not as familiar. The nuclear removal in these cataract patients is going to be similar to what a surgeon will find in a patient having a refractive lensectomy, so I believe that an effort to learn the subtleties of removal of the softer lens now will pay off later.

The Surgery
• Preop. I usually have an intuitive feeling about the presence of a softer lens if the patient is younger (30s or 40s) or has PSC. A nuclear densitometer would be able to tell me for sure, but this is a piece of equipment found more in research centers than in ophthalmology practices. Generally, you have to trust what your experience tells you following the examination. Once you're in surgery and the softer lens presents itself, you have to have a fallback plan available.

• Use the right tools. First of all, you need to look at the big picture. Because postop inflammation is the leading concern with these patients, consider such things as the type of anesthesia, incision size and the amount of phaco energy you'll be using. Because you want the most rapid visual recovery possible for this group of patients, all these things matter.

Your phaco machine will have a great impact on the eye with the soft nucleus. Some recent phaco technology upgrades like the AMO Sovereign with WhiteStar, the Alcon Legacy with AdvanTec/NeoSonix and the Bausch & Lomb Millennium, make these better machines to use on softer lenses because they help surgeons re-move a nucleus with less intraocular trauma.

Regardless of the machine you use, pay attention to the different modes from which you can choose. Most ma-chines have a mode programmed for epinuclear removal. This is probably the best mode to go into for the softer nuclei. This setting allows for less phaco energy, but still provides a fair amount of vacuum, so that the nu-clear material stays at the tip. It's safer, too, because there's less chance of surge and rupture of the posterior capsule.

Eventually, the removal of softer lenses may be a place where laser phaco will make sense. Theoretically, the newer phaco technology will produce less heat at the tip. Because there is less heat and less trauma, bi-manual procedures become easier and safer. As IOLs can be delivered through smaller incisions, we're going to be removing the cataract or the lens through smaller incisions as well, us-ing the smallest ones we can get away with. Again, you're looking for anything that will offer rapid visual recovery to this group.

Once you've made all of these very important decisions, then removing the nucleus is the only thing that sets this procedure apart from all the other cataract surgeries. It's time to think of ways that you can remove the soft nucleus more predictably.

• Hydrodissection. This is vitally important with the soft nucleus. Try to be sure to surround the entire nucleus with fluid, so that there is some mobility. One challenge in cases like this is that they tend to have sticky cortex that's very adherent to the nucleus and the capsular bag, making it somewhat difficult to get adequate hydrodissection.

Too often it will feel like you've accomplished hydrodissection, but you actually haven't and the nucleus just won't rotate. Though the inclination to proceed will sometimes be strong, resist it, as this can become a problem by introducing the risk of capsular tears. I recommend hydrodissection in multiple regions, not just in one or two spots but maybe four or five.

Try to get as much rotation as possible. It's very difficult to engage the nuclear material with whatever instrument you're using to rotate the nucleus because it's soft. So it just runs right through the nuclear material and doesn't separate itself from the cortex and the capsule. Spending a little more time on this step and getting a good, thorough hydrodissection will reduce problems later.

• Tilt. If the nucleus is super soft, try to tilt the whole thing. Do a full tilt, even through a smaller capsulorhexis of about 4.5 mm or 5 mm. If the nucleus is soft enough, it can be prolapsed up and into the anterior chamber with complete and guarded hydrodissection. Don't put any heavy energy into it. Gradually it will start to come out through the capsulotomy and you can proceed with nuclear removal once the nucleus is tilted up. Try it either vertically like David Brown (vertical flip) or take it all the way out and put it back down like Bill Maloney (full flip, supracapsular phaco). Because you'll be using less phaco energy on a soft nucleus, this is one of those times where a tilt of the nucleus vertically is not likely to be a problem for the corneal endothelium. In addition, a high viscosity viscoelastic is best to ensure protection of the endothelium.

• A bit of hardness. If the nucleus is starting to show some hardness, it's probably best to try to use chopping or cracking maneuvers to remove it. What I like to do with eyes like this is make a central groove and do a hemiflip—just pull up one half and then the other. Of course, this assumes that the surgeon can separate the two halves. If not, you may have to do additional hydrodissection and get up one half at a time. I believe the majority of the softer nuclei can be removed with full flips if they're very soft or with hemiflips if there's some firmness.

• Cortical cleanup. Once the lens has been removed, it's best to spend a little extra time in cortical cleanup for the younger patients. I like to use an I/A tip with a 45-degree bend in it to more effectively remove the subincisional cortex. It bends around the incision, not going straight in, allowing me to grab the cortex beneath it and scoop it out.

For younger patients, posterior capsule opacification is a common problem and I try to do anything I can to reduce the incidence of it. Since studies give credit to anterior capsular overlap onto the optic edge for PCO reduction, I purposely mark the cornea with a 6.0 mm OZ marker to help guide my anterior capsulotomy (capsulotomy diameter mark or CDM). I also tend to use heavier doses of topical steroid as well as nonsteroidal anti-inflammatories, be-cause these patients tend to have more postoperative in-flammation. Be sure to watch for unusual inflammatory problems in the immediate postoperative period.

A discussion of the challenges in removing softer nuclei has been underserved to some degree. Many of us just assume that we've been doing cataract surgery so long that we don't need to learn how to remove a nucleus. But because these nuclei have a different character to them, I think it takes a different technique. Though most ophthalmologists spend more time discussing really dense nuclei, we need to remember that, in their own way, softer lenses can sometimes be as challenging as mature ones. 

R. Bruce Wallace, III, MD, is Clinical Professor of Ophthalmology, LSU Medical School; Assistant Clinical Professor of Ophthalmology, Tulane School of Medicine; and Medical Director—Wallace Eye Surgery, Alexandria, La. Contact him at (318) 448-4488; or at rbw123@aol.com.