Exfoliation syndrome in Nordic countries:: a comparative histopathological study of Danish and Finnish eyes with absolute glaucoma and uveal melanoma

Purpose: To compare the frequency of exfoliation syndrome (EXS) in Denmark and Finland in eyes enucleated for absolute glaucoma and uveal melanoma and to correlate these results to reported clinical prevalence rates. Methods: The material consisted of 304 and 39 eyes consecutively removed because of absolute glaucoma and of 240 and 149 eyes enucleated because of uveal melanoma in Denmark and Finland, respectively. Histological sections of all eyes were stained with haematoxylin-eosin and periodic acid-Schiff and examined under a light microscope for EXS. Diagnosis of EXS was made by the consensus of the investigators. Results: In absolute glaucoma eyes, EXS was observed in 12 out of 304 eyes (3.9%, 95% CI 2.1-6.8) in Denmark, and in 16 out of 39 eyes (41%, 95% CI 26-58) in Finland (p < 0.0001). In the melanoma eyes, EXS was noted in two out of 240 eyes (0.8%, 95% CI 0.1-3.0) in Denmark and in nine out of 149 eyes (6.0%, 95% CI 2.8-11) (p < 0.0037) in Finland. Conclusion: The frequency of EXS was significantly higher in eyes removed for absolute glaucoma and malignant melanoma in Finland than in Denmark. This supports the clinical impression that EXS is rare in Denmark compared to other Nordic countries.