Evidence supports cataract surgery for IOP control in exfoliation syndrome

Take-home message: Cataract surgery lowers IOP in eyes with exfoliation syndrome (XFS) or exfoliation glaucoma (XFG), and it might even change the natural history of glaucoma in eyes with XFS. However, it may also be appropriate to combine phacoemulsification with glaucoma surgery in certain patients with XFG.

By Cheryl Guttman Krader; Reviewed by Karim F. Damji, MD, and Lisa Heckler, MD

Edmonton, Alberta, Canada-Cataract surgery can be beneficial for lowering IOP in eyes with exfoliation syndrome (XFS), although it may need to be augmented with glaucoma surgery in some patients, according to Karim F. Damji, MD, and Lisa Heckler, MD.

Though there is evidence that cataract surgery can help with IOP control for a period of at least 2 to 5 years, decisions on whether to perform phacoemulsification alone or combined with glaucoma surgery, and with which glaucoma procedure, depends on where patients lie on the spectrum of glaucoma and the mechanism of their disease, Dr. Damji said.

“Our surgical approach in eyes with XFS is to do phaco alone if they have no or early glaucoma,” said Dr. Damji, professor and chairman, Department of Ophthalmology and Visual Sciences, University of Alberta, Edmonton. “However, close follow-up is important because IOP can rise in the immediate postoperative period and unpredictably over time after a ‘honeymoon period’ with good IOP lowering.

“Adding a glaucoma procedure is suggested in patients with XFS and cataract who have moderate to advanced glaucoma with uncontrolled IOP on medications, although the jury is still out on what is the best procedure for that group,” he added.

Choosing a glaucoma procedure

XFS is one of the most common identifiable causes of open-angle glaucoma (OAG), if not the most common cause. However, XFS can also lead to closed-angle glaucoma or the two mechanisms may co-exist, and that is an important consideration when choosing a glaucoma procedure, Dr. Damji noted.

Microinvasive glaucoma surgery (MIGS) is considered an option for eyes with XFS, cataract, and moderate stage OAG or even early OAG, especially if IOP is not well controlled. However, trabeculectomy with an antimetabolite is recommended if the glaucoma is advanced and/or IOP is very poorly controlled.

“If the cataract is not very significant and elevated IOP and glaucoma are the significant issues, surgeons can opt to do a glaucoma procedure alone, realizing that the cataract may get worse over time,” Dr. Damji added.

If the patient has angle-closure glaucoma alone or in combination with a trabecular dysfunction, phacoemulsification is performed with goniosynechialysis of peripheral anterior synechiae. MIGS or trabeculectomy is often added as well, with the choice between the two types of glaucoma surgery based on the stage of glaucoma, level of IOP control, and the surgeon’s own preference.

Other issues are also factored into the surgical decisions, including ocular and patient-related features.

“If we are adding a glaucoma procedure, the choice may be influenced by whether the patient has a thin conjunctiva, a cloudy cornea, zonular status, and any use of anticoagulant medications,” Dr. Damji said. “Of course, involvement of the patient and the patient’s care partner(s) is also critical.”

IOP-lowering effect

Discussing the IOP-lowering effect of cataract surgery in eyes with XFS, Dr. Damji presented a prospective, multicenter trial he participated in while on faculty at the University of Ottawa. The Lindberg Society encouraged the project because-while there were a number of studies reporting that cataract surgery was associated with IOP lowering in eyes with XFS-all of the research was retrospective, he explained.

To explore the hypothesis that patients with XFS would have a greater drop in IOP after cataract surgery than eyes without XFS, the trial followed 71 patients with XFS and 112 patients without XFS for 2 years after cataract surgery [Damji KF, et al. Br J Ophthalmol. 2006;90:1014-1018].

The results showed mean IOP reduction from baseline was significantly greater in the eyes with XFS than those without XFS (–1.85 versus –0.62 mm Hg).

In addition, analyses of intraoperative parameters showed the amount of irrigation fluid used during the procedure was higher in subgroups of eyes with XFS, whether or not they had glaucoma, than in controls without XFS.

Further, a multivariate analysis showed a correlation between volume of irrigation fluid used during surgery and the magnitude of IOP lowering in eyes with XFS such that IOP lowering increased as the volume of irrigation fluid increased. No such correlation was seen in eyes without XFS.

“The results must be considered carefully because our study groups were small and multiple surgeons were involved,” Dr. Damji said. “However, one hypothesis is that prolonged irrigation along with aspiration might be beneficial for washing exfoliation material out of the anterior segment.”

Altering the risk of glaucoma

Dr. Damji also raised the idea that early cataract surgery may change the natural history of glaucoma in eyes with XFS. Further study is needed to investigate that possibility, he said.

However, results from a retrospective study including 882 patients with XFS operated on by a single surgeon (Bradford J. Shingleton, MD) showed that less than 3% of those eyes progressed to needing glaucoma medication during follow-up extending to 10 years [Shingleton BJ, et al. J Cataract Refract Surg. 2008;34:1834-1841].

Interesting as well, results of a study from the LV Prasad Eye Institute in India including 62 patients with XFS showed flattening of the diurnal IOP curve after cataract surgery [Rao A. Semin Ophthalmol. 2012;27:1-5].

Karim F. Damji, MD

E: kdamji@ualberta.ca

This article was adapted from Dr. Damji’s presentation during Glaucoma Subspecialty Day at the 2014 meeting of the American Academy of Ophthalmology.

Lisa Heckler, MD

E: lisa.heckler@gmail.com

Dr. Heckler, who co-authored the presentation with Dr. Damji, is clinical assistant professor of ophthalmology, University of Montréal, Québec. Dr. Damji and Dr. Heckler have no relevant financial interests to disclose.