Combined exfoliation and pigment dispersion: An overlap syndrome

Purpose: To describe a series of patients with combined pigment dispersion syndrome (PDS) and exfoliation syndrome (XFS) and to introduce a concept, the overlap syndrome, to aid in assessing multiple risk factors for glaucomatous damage. Methods: A retrospective review of the records of all patients on our data-base who carried a diagnosis of both PDS/pigmentary glaucoma (PG) and XFS/exfoliative glaucoma (XFG). Results: We identified 26 patients as having both XFS/XFG and PDS/PG. The average age was 64.3 ± 9.8 years and 19 of 26 were men. All patients had bilateral PDS/PG. Bilateral XFS/XFG was present in 9 of 26 patients, and of the 17 patients with unilateral involvement, the left eye was affected in 13. Conclusion: Both XFS and PDS are common. Middle-aged patients with known PDS/PG should be suspected of having the onset of XFS if 1 eye escapes intraocular pressure control. Patients presenting with unilateral XFG may also have signs of PDS/PG, often remitted. We define an overlap syndrome as the appearance of a new co-morbidity for glaucomatous damage in a patient with a pre-existing risk factor, which then changes the course, and prognosis of the disease. This concept should be particularly useful in dealing with secondary and normal-tension glaucoma.