Background: The pathogenesis of polypoidal choroidal vasculopathy (PCV), and even its clinical features, are controversial. Previous histopathological studies have identified different features; either dilated choroidal vessels or intra-Bruch's neovascularization. These differences might be partly attributable to the influence of the disease stage. We therefore evaluated the clinical features of early and late stage PCV.
Methods: The medical records of 110 eyes of 97 PCV patients were retrospectively reviewed. The time between the subjective onset of visual abnormality and examination at our clinic and the greatest linear dimension of the total lesion at the first examination were investigated. The period of disturbed vision and lesion size data were placed in ascending order to determine the first quartile point. Eyes with both values at or below the first quartile point were classified as 'small-short' (early stage). Eyes with both values equal to at least the third quartile point were classified as 'large-long' (late stage). Fundus photography, indocyanine green and fluorescein angiography, visual acuity, and clinical course were compared.
Results: Twelve eyes from 12 patients were small-short cases (period of disturbed vision of 1 month or less, lesion size 2.0 disc diameters or less). Eleven eyes from ten patients were large-long cases (period of disturbed vision 36 months or more, lesion size at least 5.0 disc diameters). The large-long eyes were characterized by occult choroidal neovascular membrane or scar tissue secondary to exudative age-related macular degeneration. Noticeable in the small-short eyes were atrophic changes in the retinal pigment epithelium, choroidal vessel hyperpermeability and pulsation. The visual prognosis and clinical course were different between the groups.
Conclusions: The difference of clinical features between the groups might reflect different disease stages, although not all of the features observed in the small-short group appeared to represent the early stages of those recorded in the large-long group. Thus, the variation in histopathologic features among previous reports might be partly attributable to differences in disease stage.