Basal linear deposit and large drusen are specific for early age-related maculopathy

Objective: To determine the distributions of basal laminar and basal linear deposits in Bruch membrane (BM) with respect to age and early age-related maculopathy (ARM). Methods: The foveas of 41 human eyes (<60 years [n = 9]; greater than or equal to 60 years [n = 32]), preserved no later than 3.5 hours post mortem, were examined using light and electron microscopy. Ten eyes met histopathologic criteria of the Alabama Age-related Macular Degeneration Grading System for early ARM. We calculated the specificity, sensitivity, and odds ratios for the association of basal laminar and basal linear deposits with early ARM. Results: Both deposits occurred only in eyes older than 60 years. The highest specificities and sensitivities for early ARM were attained for eyes that had basal linear deposits or large (>125 mu m) drusen, followed by eyes with any quantity of basal laminar deposits that also contained membranous debris. Eyes with ARM were 24 times more likely than age-matched control eyes to have basal linear deposits or large drusen (P=.002). Conclusions: Basal linear deposits and large drusen with membranous contents constitute different morphologic forms of the same ARM-associated lesion and may be significant for progression to late ARM.