This article is more than 5 years old. Information may no longer be current.
Successful cataract surgery for patients with pseudoexfoliation
Click Here to Manage Email Alerts
Pseudoexfoliation is a condition in which an amyloid type membrane is deposited on the surface of the lens, usually in a classic pattern. Roughening around the pupillary border may be observed. Pseudoexfoliation increases the incidence of developing cataracts, weakens the zonules and capsules and leads to more serious complications during cataract surgery.1
 Alan S. Crandall |
Pseudoexfoliation glaucoma, a form of chronic open angle glaucoma, develops in a small percentage of patients with pseudoexfoliation. Pseudoexfoliation is not only ocular, it is also systemic, and patients with pseudoexfoliation have an increased risk for stroke at a younger age.
Pseudoexfoliation is common in patients from Scandinavia and eastern Europe, and has been observed in almost every population worldwide, although prevalence depends on location. American states, such as Utah, Minnesota and Iowa, have a high number of descendants from Russia and northern European countries, such as Sweden, Denmark and Norway. In my experience in Salt Lake City, Utah, I perform five to 10 cataract surgeries per week on patients with pseudoexfoliation, whereas a surgeon in Philadelphia, which has a different patient demographic, may perform one case every other week.
Increased risk for glaucoma and complications
"Pseudoexfoliation increases the incidence of developing cataracts, weakens the zonules and capsules and leads to more serious complications during cataract surgery."
— Alan S. Crandall, MD
Most patients with pseudoexfoliation experience no symptoms; much like patients who have glaucoma, they often are unaware that they have the condition. Slit lamp examination can reveal material deposits on the lens surface and the chamber deepening asymmetrically, which may suggest zonular instability.
Patients with pseudoexfoliation present with glaucoma at a higher rate than other patients, so they should be examined every 1 to 2 years. They also have more pigment than the average person but a similar amount of pigment as patients with pigmentary dispersion glaucoma. The mechanism of pigmentary dispersion glaucoma is likely related to the deposition of material in the angle from pseudoexfoliation over time. Before dilating pupils for cataract surgery, the surgeon should determine the amount of pigment present because it correlates with the potential for postoperative pressure spikes.
Although most patients with pseudoexfoliation do not experience any significant complications during cataract surgery, surgeons should inform these patients that they have an increased risk for complications. Pupils may not dilate well, zonules may be loose, and capsular bags are more fragile in patients with pseudoexfoliation.
Tools and instruments
It is important for surgeons to be prepared with a full set of microinstruments for every cataract surgery, but it is especially vital when performing surgery on patients with pseudoexfoliation.
Viscoelastic devices, such as DisCoVisc (4% sodium chondroitin sulfate, 1.65% sodium hyaluronate, Alcon Laboratories, Inc.) and Healon 5 (2.3% sodium hyaluronate, Abbott Medical Optics), can enlarge the pupils and help maintain space. Malyugin rings (Microsurgical Technology) also assist in pupil dilation, and the Ahmed Capsular Tension Segment (Morcher GmbH), which was recently approved in the United States, aids with zonule support.
Newer phacoemulsification platforms, such as the OZil torsional system on the Infiniti Vision System (Alcon Laboratories, Inc.), the Ellips transversal ultrasound on the WhiteStar Signature System (Abbott Medical Optics) and the Stellaris Vision Enhancement System (Bausch & Lomb), are efficient for cataract surgery in patients with dense cataracts, reducing the amount of energy delivered to the eye. I use all three platforms, but for the majority of my cases, I use the Infiniti system.
Most data suggest that complication rates for the new generation of acrylic and silicone IOLs are similar. Therefore, surgeons can implant the lens they are most comfortable using, although an acrylic lens may be better suited for a patient with retinopathy.
Surgical technique
Surgeons must be meticulous when performing cataract surgery on patients with pseudoexfoliation and aim to decrease zonular stress. If it is known that a patient has zonular weakness, the surgeon can stain the capsule with trypan blue to easily view the capsulorrhexis during surgery (Figure 1). Using a mini capsulorrhexis forceps, I create a standard capsulorrhexis that is sufficiently large, such as 5.5 mm, so that the capsule does not contract, because capsule phimosis may be a risk factor for late subluxation. Slight wrinkling in the capsule just in front of the capsulorrhexis is a sign of generalized zonulopathy. If wrinkling is observed, then the surgeon should maneuver slowly, ensuring that all vector forces are perfect.
 Figure 1. The surgeon can stain the capsule with trypan blue to easily view the capsulorrhexis during surgery. |
 Figure 2. The surgeon should ensure that the nucleus is free before attempting pre-chop. |
To decrease zonular stress, little torque should be used. Also, the surgeon should ensure that the nucleus is free before attempting pre-chop (Figure 2). I find that vertical chopping is the most zonular friendly method to debulk the nucleus. The OZil handpiece provides control and holds the nucleus so that chopping is made easy (Figure 3). The handpiece gently controls the flow, and material remains at the tip (Figure 4). I remove cortex either bimanually, with a silicon-sleeved irrigation and aspiration (I&A) tip, or with a Barrett I&A tip (Microsurgical Technology), and insert an IOL with an injector that is soft during entry and zonular friendly. A 2.2-mm incision provides control during the procedure, and an IOL can be injected easily and safely, and unfolded gently in the capsular bag.
 Figure 3. The phaco handpiece holds the nucleus so that chopping is made easy. |
 Figure 4. The phaco handpiece controls the flow while material remains at the tip. |
Because patients with pseudoexfoliation often have glaucoma, many are at risk for high postoperative IOP spikes. To avoid pressure spikes, I recommend that surgeons remove all viscoelastic and monitor patients 3 to 6 hours after surgery and 1 day postoperatively. My postoperative regimen includes drops such as moxifloxacin (Vigamox, Alcon Laboratories, Inc.), gatifloxacin (Zymar, Allergan) or prednisolone acetate 1% (Pred Forte, Allergan), and if manipulation during surgery was significant, I prescribe a 2- or 3-day course of acetazolamide (Diamox, Duramed Pharmaceuticals) and topical antibiotic drops.
Spontaneous IOL dislocation
My colleagues and I performed a retrospective observational study on eight eyes in seven patients with clinically diagnosed pseudoexfoliation who experienced spontaneous IOL dislocation.2 Mean time for dislocation was 85 months (7 years and 1 month; range, 57 to 115 months) after IOL implantation. Furthermore, in our 10-year clinical experience with 400 IOL subluxations, we found that spontaneous dislocation occurred about 8.5 years after uncomplicated cataract surgery. Although we could not definitively determine any risk factors for late IOL dislocation, presence of pseudoexfoliation is a factor in these cases. Therefore, I recommend that surgeons closely monitor patients with pseudoexfoliation after cataract surgery.
Managing IOL dislocation
Almost all subluxations require surgical management because the lens has moved in the eye and may have dropped onto the macula and hit the retina. Surgical intervention may not be necessary for slight phacodonesis, but close observation is important to prevent a total dislocation. During the procedure, the surgeon must first retrieve the lens, which is often in the capsular bag. If the lens is in the bag and appears intact, I either suture the lens to the sclera or fixate it to the iris. In some patients, the surgeon must explant the subluxed lens and implant a new IOL.
Although patients with pseudoexfoliation have an increased risk for complications, most experience routine cataract surgery. To minimize risk for complications, surgeons should determine zonular stability preoperatively, have all necessary instruments available during surgery and monitor patients for pressure spikes postoperatively.
References
- Shingleton BJ, Crandall AS, Ahmed II. Pseudoexfoliation and the cataract surgeon: preoperative, intraoperative, and postoperative issues related to intraocular pressure, cataract, and intraocular lenses. J Cataract Refract Surg. 2009;35(6):1101-1120.
- Jehan FS, Mamalis N, Crandall AS. Spontaneous late dislocation of intraocular lens within the capsular bag in pseudoexfoliation patients. Ophthalmology. 2001;108(10):1727-1731.
Dr. Crandall is clinical professor and senior vice chairman of ophthalmology and visual sciences, director of Glaucoma and Cataract at the Moran Eye Center, University of Utah School of Medicine.
Surgical Videos
