Figure 1. Pseudoexfoliation in a 44-year-old Sri Lankan male
Associate Professor Peter G Swann
BSc(Hons) MAppSc FBCO FAAO
School of Optometry and Vision Science, Queensland University of Technology
A 44-year-old Sri Lankan male presented to the Optometry Clinic at QUT. He was an accountant and was struggling to see at near. It was his first eye examination.
Visual acuity was R 6/6 L 6/6 with a small hyperopic refraction and R N5 L N5 with an appropriate reading addition. There were no relative afferent pupil defects and intraocular pressures (IOP) were R 15 L 25 mmHg at 10 am. Slitlamp examination revealed a normal right anterior segment; the left showed a slightly distorted left pupil together with white pseudoexfoliation material on the left anterior lens capsule (Figure 1).
The right fundus was normal and the left optic disc was markedly cupped. Visual fields, examined with the Humphrey Field Analyzer, revealed a normal right field and advanced glaucomatous field loss in the left eye (Figure 2).
Figure 2. The left visual field showing advanced glaucomatous field loss
The patient was lost to follow-up before a management plan could be initiated.
This patient’s case was interesting because of his age at diagnosis. Pseudoexfoliation material, which appears to be systemically synthesised and is similar to amyloid, is usually seen deposited on structures in the anterior segment and in many organs of the body. It is typically diagnosed in older patients, predominantly women, and rarely under the age of 50 years.
Most races of the world can be affected but the condition is more common in Scandinavia for reasons that are not well understood. Pseudoexfoliation is a term originally coined to distinguish it from true exfoliation of the lens capsule, a rare condition seen in people exposed to infrared radiation and intense heat sources such as glassblowers.
White flaky deposits are seen on the anterior lens capsule and frequently the pupil border (Figure 3). There is usually a central disc of material (Figure 4); a clear zone where deposits have been removed by rubbing from iris movement; and a peripheral band, the anterior edge of which frequently appears serrated (Figure 5).
Figure 3. Pseudoexfoliation material on the anterior capsule and the pupil border
Figure 4. Central disc of deposits on the anterior capsule
Figure 5. Peripheral band of material
Pigment dispersion is often a feature in these patients. Gonioscopy may reveal trabecular hyperpigmentation (Figures 6 and 7). Pigment and pseudoexfoliation material can impede aqueous outflow and lead to secondary open angle glaucoma. A weakening of the lenticular zonules and capsule is a potential issue when cataract surgery is contemplated. The condition is best observed through a dilated pupil although these patients tend to dilate poorly.
Figure 6. Gonioscopic view of the left inferior angle of an 80-year-old white male with pseudoexfoliation in the other eye
Figure 7. A gonioscopic view of the patient’s right inferior angle; pigment dispersion was also present and the angle was more pigmented
It is important to examine the anterior segment again when the pupil is dilated as pseudoexfoliation can be subtle and effectively hidden by the iris. Repeated IOP measurements after dilatation are also important as pressure spikes can occur.
If glaucoma develops in these patients, medical therapy is the same as for primary open-angle glaucoma; however, this alone may not be enough to control IOP. Argon laser trabeculoplasty may be required and is usually initially successful although its effects can wane with time. Selective laser trabeculoplasty may be preferred as it is repeatable. Surgical intervention in the form of a trabeculectomy may be considered if IOP is still not at a desired level.
These patients must be most carefully followed. If they do not have glaucoma, a thorough review should be undertaken at least every 12 months.
The author thanks optometrist Wesley Robertson for his permission to use Figure 4.
Bruce A, Loughnan M. Anterior Eye Disease and Therapeutics A-Z. 2nd ed 2011; Elsevier, Sydney, pp 260.
Bruce AS, O’Day J, McKay D, Swann PG. Posterior Eye Disease and Glaucoma A-Z. 2008; Elsevier, Sydney, pp 222.