Eyeworld

EW CORNEA 40 October 2011 What to consider pre-op C ataract surgery is one of the safest, most efficient procedures around and typically yields outstand- ing refractive results for patients. But occasionally, a patient has an underlying condition such as Fuchs' dystrophy that makes cataract extraction, and achieving stellar vision post-op, more complex than normal. A proper pre-op exam is a physician's first line of defense for a successful surgery and meeting the patient's expectations. Fuchs' dystrophy is a slowly pro- gressing disease characterized by the thickening of Descemet's membrane, accumulation of guttae on the corneal endothelium, endothelial cell loss, and even subepithelial scar- ring in late stages. "There are some things you should do differently when doing cataract surgery on a patient with Fuchs' dystrophy," said W. Barry Lee, M.D., Eye Consultants of Atlanta. "There are a couple of extra things you need to think about." First and foremost, it's crucial the disease is discovered during the pre-op exam. "The most critical step is seeing the guttae on the cornea," said Dr. Lee. "Believe it or not, that's missed a lot by cataract surgeons because they focus on the cataract itself and don't look at the cornea." Mild cases of Fuchs' can be over- looked during the pre-op exam, es- pecially by busy surgeons focused on getting through a long patient list. "It takes some time to look at the back of the cornea," said Dr. Lee. "Sometimes physicians just miss it. Slow down, be mindful, use high magnification, and really look at the back of the cornea." Also, listen to patient com- plaints carefully. For example, if a patient experiences fuzzy vision in the morning that gradually clears as the day progresses, that's usually a symptom of corneal edema and needs to be taken seriously. If Fuchs' is discovered, the physician has some decisions to make. Does the patient need cataract surgery alone or a combined procedure? What in- traocular lens is the best for this situ- ation? To determine which type of pro- cedure is appropriate, Dr. Lee recom- mended a central pachymetry test. If the value is high, he advocates a combined cataract and DSEK proce- dure. "I usually use 640 microns as my cutoff," he said. "If the value is more than 640 microns, I know my chances of the cornea clearing after cataract surgery are pretty poor." Douglas Koch, M.D., Allen, Mosbacher, and Law Chair in Oph- thalmology, Cullen Eye Institute, Baylor College of Medicine, Hous- ton, uses 630 microns as his cut-off point. If the cornea is thicker than 630 microns, he recommended doing a DSEK followed by a later cataract surgery or combining both procedures into one. Dr. Koch pointed out that some- times the guttae are so significant that their presence alone can cause a drop in vision post-op. "In that situation, one might consider a DSEK even if the cornea doesn't have frank edema," he said. "I think it depends on the patient's expectations and overall level of vi- sion. If vision is generally quite good and you can pinpoint the cataract as the major cause, then you [remove] the cataract. If you sense the vision is 20/60 but half of it is the cornea, then you have to have a discussion with the patient about how he or she would like to proceed." Dr. Koch has found that most patients in that situation will leave the cornea. They'll be satisfied with a 50-60% improvement in vision and find it acceptable for their lifestyle. When choosing an IOL for these patients, Dr. Koch advised surgeons to stay away from multifocal lens implants and proceed with caution when considering a toric lens. "The reason I'm hesitant is be- cause if I put in a toric lens and the patient needs a DSEK, it could change his astigmatism. It could change anything," he said. "Then I've wasted the patient's money and might actually have put him in a worse optical situation." However, if the Fuchs' is rela- tively mild and the patient will never need a DSEK, a toric lens is a reasonable choice for those with a diopter or more of astigmatism. Finally, pre-op counseling is ex- tremely important for Fuchs' cataract patients. Patients may never get back to 20/20 vision even after the cataract is removed, and it's im- perative they have realistic expecta- tions of their visual acuity post-op. "Patients need to be aware that their vision may not be perfect when they're done," said Dr. Lee. "They may not be 20/20, and they may feel like their vision is still a lit- tle blurry. Unfortunately, some cases never clear and patients end up needing DSEK. It might be soon after cataract surgery, or it might be years down the road. But be aware by Faith A. Hayden EyeWorld Staff Writer Cataract surgery and the Fuchs' dystrophy patient C ataract surgeons have several decisions to make when con- fronted with a patient with a cataract and simultaneous corneal pathology. One of the most common corneal conditions that cataract surgeons need to manage is the patient with Fuchs' dystrophy. The surgeon needs to evaluate how much of the visual loss is due to the cataract and how signifi- cant the corneal disease is. Prior to DSEK many surgeons would defer cataract sur- gery for fear of the risk of corneal decom- pensation and the need for a penetrating keratoplasty (PK). The patient who would require a PK faces a long visual recovery and numerous clinic visits. With DSEK now being the procedure of choice for corneal edema and the out- standing outcomes that result from DSEK, the cataract surgeon can now be more ag- gressive with recommending cataract sur- gery in a patient with Fuchs' dystrophy. If the cornea decompensates post-opera- tively, the patient can undergo DSEK and achieve a rapid visual recovery. With every patient with Fuchs' and cataract, the surgeon needs to make the decision on what procedure to recom- mend: cataract surgery alone, DSEK alone, or a combined procedure. I have asked two talented cornea and cataract surgeons, Douglas Koch, M.D., and Barry Lee, M.D., to give us their approach to the Fuchs' dystrophy patient with cataract. Edward J. Holland, M.D., cornea editor Guttae in Fuchs' dystrophy Source: W. Barry Lee, M.D. Guttae and amyloid deposits Source: W. Barry Lee, M.D. Corneal edema in Fuchs' dystrophy Source: W. Barry Lee, M.D. continued on page 41 Cornea editor's corner of the world 40-45 Cornea_EW October 2011-dl2_Layout 1 9/29/11 3:43 PM Page 40

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