Fluorescein angiographic identification of optic disc drusen with and without optic disc edema.

BACKGROUND: The fluorescein angiographic criteria for differentiating optic disc drusen (ODD) from optic disc edema have been unclear. We designed a study to identify distinguishing angiographic features of each and to apply them to cases where both drusen and edema were present.
METHODS: A computer search was performed for cases evaluated in a university academic neuro-ophthalmology consultative practice and coded as ODD; all cases were reviewed, and those with fluorescein angiography were selected for further study. Cases were classified as either buried or surface ODD. Ten cases with papilledema were selected for comparison. Eight cases of coexistent drusen and edema were identified. Autofluorescence, early leakage, early blockage, early and late nodular staining, late peripapillary staining, and late leakage were tabulated.
RESULTS: Two hundred sixteen cases of ODD were identified; 62 (116 eyes) had adequate fluorescein angiography for study. Twenty-three eyes were classified as surface ODD; 90% demonstrated early nodular staining of the disc, with late nodular staining in 90% and late circumferential peripapillary staining in 22%; autofluorescence was visible in 93% with preinjection photography. Eighty-three eyes were classified as buried ODD; 25% demonstrated early nodular staining, with late nodular staining in 29% and late circumferential peripapillary staining in 80%; autofluorescence was visible in 12% of those with preinjection photography. In 9 eyes, buried ODD were present with superimposed true edema. In these eyes, early dye leakage, late nodular hyperfluorescence, and late leakage were present.
CONCLUSION: Early and late fluorescein angiographic features reliably distinguish ODD from edema and may be particularly useful when the conditions coexist.