Pseudoexfoliation syndrome presents many potential risks of intraoperative and postoperative complications in cataract surgery. These include lens/IOL dislocation, glaucoma, endothelial cell decompensation, and increased blood-aqueous barrier (BAB) disruption. Therefore, surgery should be performed carefully. The soft-shell technique using viscoelastic material is mandatory to limit damage to corneal endothelial cells. The viscoelastic material should be completely removed to avoid a postoperative IOP rise. To reduce BAB disruption, nonsteroidal antiinflammatory eyedrops and steroids should be given preoperatively and intraoperatively.
The most difficult problem in pseudoexfoliation is intraoperative and postoperative zonular dehiscence resulting from weak zonules caused by progressive zonular digestion. The dehiscence can lead to intraoperative and postoperative dislocation of the crystalline lens or IOL. I proposed the following to avoid this condition.
In a relatively young, healthy individual with pseudoexfoliation syndrome, I would attempt to create a larger capsulorhexis, but one that is completely apposed on the IOL optic. A silicone IOL, although it has sharp edges, should not be used because it causes strong anterior capsule fibrosis followed by shrinkage. I would implant a hydrophobic 3-piece IOL such as the AcrySof or Sensar OptiEdge because they are effective in preventing PCO and may better resist the capsule shrinkage that can occur with other IOLs including the single-piece AcrySof. It is important to prevent PCO because Nd:YAG laser capsulotomy can cause a shock wave that can weaken zonules. All these surgical measures are to avoid further weakening of the zonules.
The most difficult decision may be whether to use a CTR with or without suturing to prevent possible late dislocation. Jehan and coauthors1 describe 8 cases of late intracapsular IOL dislocation in pseudoexfoliation patients. If zonular dehiscence is found preoperatively or intraoperatively, a CTR should be used to facilitate, achieve, and complete phacoemulsification. When an anterior chamber IOL is used, late dislocation will not occur. However, I would avoid using an anterior chamber lens in pseudoexfoliation patients because it can damage corneal endothelial cells, further disrupt the BAB, and induce glaucoma. The question is whether the CTR should be sutured.
According to many clinical reports, the CTR does not effectively prevent shrinking of the capsule opening, indicating that the ring cannot prevent the shrinkage caused by capsule fibrosis. Moreover, I recently had 2 cases (in 22 eyes receiving a CTR over 3 years) of late dislocation of the originally subluxated lens that were managed inraoperatively by inserting a CTR 2 years after surgery, although the patients did not have pseudoexfoliation. Thus, unless it is sutured, the CTR does not prevent dislocation. Therefore, I fixate the CTR by suturing it to the sclera in cases of pseudoexfoliation with zonular dehiscence. Thus, if a CTR is used in cases of pseudoexfoliation, it should be sutured to avoid late dislocation.
If no zonular dehiscence is seen under the operating microscope in relatively young patients, the decision may be difficult. I would rather not implant a CTR because it does not effectively reduce shrinkage of the capsule opening. It might postpone late dislocation, but it does not completely prevent posterior dislocation unless it is sutured. Moreover, once the IOL and CTR in the capsular bag dislocate on the fundus, it is difficult to remove the ring or suture it in the ciliary sulcus. Suturing it in the sulcus is also associated with surgical risks such as retinal detachment and vitreous bleeding, and this approach might not be warranted as opposed to that used in eyes with zonular dehiscence. Therefore, in of the absence of signs of zonular dehiscence, I would not use the ring. Rather, I will wait until the pathogenesis of ocular exfoliation syndrome is clarified and more exact figures on late dislocation are verified and published.
1. Jehan FS, Mamalis N, Crandall AS. Spontaneous late dislocation of intraocular lens within the capsular bag in pseudoexfoliation patients. Ophthalmology 2001; 108:1727-1731