March 2014

 

CATARACT

 

Cataract/IOL complications: Moran CPC reports

A case of uveitis-glaucoma-hyphema (UGH) syndrome following cataract surgery


by Scott Cole, MD, MS, Liliana Werner, MD, PhD, and Nick Mamalis, MD

 
 

Scott Cole, MD

Scott Cole, MD, MS

Nick Mamalis, MD

Nick Mamalis, MD

Liliana Werner, MD

Liliana Werner, MD, PhD

 
single-piece hydrophobic acrylic IOL

Figure 1: Clinical photograph showing the temporal haptic of a single-piece hydrophobic acrylic IOL (arrows) in contact with the periphery of the iris, observed through a transillumination defect

Figure 2: Ultrasound biomicroscopy demonstrating the haptic of the single-piece hydrophobic acrylic IOL (in cross section; arrows) apposed to and thinning the peripheral iris

Figure 3: Light photomicrograph showing pigment dispersion on the surface of a single-piece hydrophobic acrylic IOL that was partially in the sulcus Source (all): Michael E. Snyder, MD

The complication described in this article is well established, and it continues to be a detriment to patient outcomes. As single-piece hydrophobic acrylic intraocular lens (IOL) designs are becoming widely used worldwide, surgeons should be aware of the likelihood of this complication going forward.

Case report

Two years prior to presentation a 70-year-old woman had cataract surgery with placement of a posterior chamber IOL in the right eye.1 Since surgery, she had bouts of blurred vision associated with combinations of anterior segment inflammation, anterior chamber red blood cells, and mild vitreous hemorrhage. A few reactive iris vessels were seen, and a peripheral transillumination defect was detected (Figure 1). On consultative examination, the acuity was 20/20 with an undesired myopic correction and the IOP was 15 mm Hg. The anterior segment was quiet and notable for a well-centered SA60AT single-piece hydrophobic acrylic lens (Alcon, Fort Worth, Texas) with the optic in the capsular bag. However, ultrasound biomicroscopy was performed, revealing that the temporal haptic of the lens was in front of the anterior capsule and in direct contact with the posterior iris surface (Figure 2). The temporal haptic extended though a wide capsulorhexis opening and was in contact with the peripheral iris, as seen through the transillumination defect overlying it. In view of the intermittent UGH syndrome, the patient elected to have an IOL exchange. This was performed uneventfully. At the six-month follow-up, the patient maintained 20/20 UCVA in the affected eye and the IOP with no medication was 13 mm Hg. The anterior segment remained without inflammation or evidence of hemorrhage. She reported no incidents of visual changes, ocular redness, or photophobia typical of her previous UGH syndrome episodes.

Laboratorial analyses and results

The specimen (explanted single-piece hydrophobic acrylic IOL) was submitted to our laboratory. Gross examination of the explanted IOL was performed, and gross photographs were taken. The optic was bisected for explantation, and both haptics were intact. No adherent fibrocellular material was seen on the optic or haptics. The lens was then evaluated and photographed under a light microscope. Under light microscopy, the IOL showed the presence of significant amounts of pigmented deposits on its anterior surface (Figure 3).1

Comments

The single-piece hydrophobic acrylic lens has square edges that have been shown to reduce the incidence of PCO. The single-piece lens incorporates these square edges not only on the optic but along both haptics as well. When a single-piece lens is placed in the capsular bag, the square optic and haptic edges are covered by the anterior and posterior capsules, provided that the capsulorhexis is centrally located and smaller than the size of the optic. When placed in the ciliary sulcus, the square edges of the lens may contact the posterior iris and ciliary sulcus uveal tissue. Such was the case of the patient described here. The pigmented deposits were found concentrated on the anterior surface of the haptic that was displaced from the capsular bag and on the corresponding optic-haptic junction.1

Other clinical and pathological reports describe iris pigment epithelial damage following implantation of a single-piece hydrophobic acrylic lens in which a haptic had displaced from the capsular bag into the ciliary sulcus.2-4 The authors hypothesize that the unpolished/textured edges and lateral surface of the displaced haptic may cause pigmentary glaucoma because of pigment epithelial disruption of the iris and ciliary body. They speculate that the haptic may have become displaced because of an excessively wide capsulorhexis. This is similar to the case we describe, in which the proximal portion of the haptic was in the capsular bag, but the distal portion coursed around the capsulorhexis margin, resting in the ciliary sulcus in direct contact with iris pigment epithelium.

Although the thick haptics, squared edges, and unpolished side wall likely contribute to sulcus irritation, the presence of a large Soemmering's ring may also be a contributing factor. The excess cortical material can result in the IOL resting closer to the posterior iris, and pigment dispersion occurs because of the optic margin rubbing against the iris epithelium. One of the interesting characteristics seen in these cases is the pigment dispersion on the anterior surface of the lenses and the haptics located in the ciliary sulcus. Associated with this finding is usually a rise in IOP, indicating pigment dispersion syndrome secondary to the IOL. This syndrome is thought to occur when contact exists between the IOL and the posterior iris, which causes an excess liberation of pigment from the iris epithelium with subsequent obstruction of the trabecular meshwork outflow pathway. Reports of glare phenomena have been associated with implantation of IOLs having square optic edges and manufactured from a hydrophobic acrylic material with a high refractive index. The finishing of the single-piece side walls were modified to give the side walls an unpolished or textured appearance. This unpolished appearance on the flat side wall of the haptics along with haptic thickness may make these lenses more likely to create iris chafing when in the sulcus.

The case described here demonstrates that various postoperative complications may develop from single-piece AcrySof IOLs (and other similar IOL designs) located in the ciliary sulcus. Furthermore, as described in other cases, the highly flexible haptics of the lens make it prone to decentration when placed in the sulcus. Also, because the optic edges can lead to irritation, the capsulorhexis should ideally be small enough to cover any exposed square edges, eliminating the possibility of IOL edge-related pigment dispersion. Single-piece hydrophobic acrylic lenses (and other similar IOL designs) should not be placed in the ciliary sulcus, but should be implanted only in the capsular bag as recommended by the manufacturer.

Differential diagnosis

1. Cell deposits may be observed on the IOL surface after cataract surgery as part of a foreign body reaction, and usually are composed of giant cells, macrophages, and fibroblast-like cells. They usually degenerate and detach from the IOL surface in the postoperative period. If necessary, they can be "dusted off" the IOL surface by using a Nd:YAG laser.

2. Cellular deposits on the IOL surface may be related to previous episodes of uveitis; however, the patient in the case described here had no previous history of uveitis.

3. Iris transillumination defects may be found in pseudoexfoliation cases, but these defects are usually located near the pupillary border and not clearly related to the IOL haptics.

References

1. LeBoyer RM, Werner L, Snyder ME, Mamalis N, Riemann CD, Augsberger JJ. Acute haptic-induced ciliary sulcus irritation associated with single-piece AcrySof intraocular lenses. J Cataract Refract Surg 2005; 31:14211427.

2. Micheli T, Cheung LM, Sarma S, et al. Acute haptic-induced pigmentary glaucoma with an AcrySof intraocular lens. J Cataract Refract Surg 2002; 28:18691872.

3. Chang DF, Masket S, Miller KM, et al, ASCRS Cataract Clinical Committee. Complications of sulcus placement of single-piece acrylic intraocular lenses: recommendations for backup IOL implantation following posterior capsule rupture. J Cataract Refract Surg 2009;35: 1445-58.

4. Kirk KR, Werner L, Jaber R, et al. Pathological assessment of complications with asymmetric or sulcus fixation of square-edged hydrophobic acrylic intraocular lenses. Ophthalmology 2012;119:907-13.

Editors' note: Drs. Cole, Werner, and Mamalis are affiliated with the John A. Moran Eye Center, University of Utah, Salt Lake City. They have no financial interests related to this article.

Contact information

Cole
: scott.cole@hsc.utah.edu
Mamalis: nick.mamalis@hsc.utah.edu
Werner: liliana.werner@hsc.utah.edu

A case of uveitis-glaucoma-hyphema (UGH) syndrome following cataract surgery A case of uveitis-glaucoma-hyphema (UGH) syndrome following cataract surgery
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