Tip of the Month
Publishing date: October 2010
Tip Editors: Ann Hoste, John Salmon and John Thygesen
Tip reviewer: Roger Hitchings
The Science behind the Tip
Although the diagnosis of pseudo-exfoliation syndrome (PEX) with a fully dilated pupil in an elderly patient should pose no difficulty, it is still too often missed. One of the more important advantages of knowing that the patient has PEX is that in case of cataract, the surgeon can be informed about it.
He/she will thus be better prepared for a challenging surgical procedure. He may want to allot more time for the operation, for example by scheduling the patient as the last on his operation list, for dealing with the possible difficulties encountered during the surgery and associated with PEX.
Inadequate dilation may require advanced small-pupil techniques. Further, fragility of the lens capsule and zonules predisposes for capsular rupture and vitreous loss. If the surgeon is given the opportunity to examine the patient before surgery, critical modifications in the surgery technique (such as use of a capsular tension ring (1)) can be planned to avoid complications.
Iridodonesis and visibility of the lens equator during eccentric gaze are subtle signs of zonular damage. In a later stage, shallow anterior chamber points to lens dislocation. Absence of these signs however by no means guarantees an uneventful operation and much may depend on the situation encountered intraoperatively.
There is an increased incidence of cataract in eyes with PEX (2). Further, chances are higher that in these elderly patients with possible age-related co-morbidity and with an aggressive form of glaucoma, the eye needing cataract surgery is the only functional one.
Contributor: Ann Hoste, Antwerp
1. Bayraktar S, Altan T, Küçüksümer Y, Yilmaz OF. Capsular tension ring implantation after capsulorhexis in
phacoemulsification of cataracts associated with pseudoexfoliation syndrome. Intraoperative complications
and early postoperative findings. J Cataract Refract Surg. 2001;27:1620-8.
2. Roth M, Epstein DL. Exfoliation syndrome. Am J Ophthalmol. 1980;89:477-81.