Certified Ophthalmic Technician (COT) Practice Test 2026 - Free COT Practice Questions and Study Guide

The type of stromal corneal dystrophy that presents with a dense gray central opacity originating from Bowman's layer is macular dystrophy. This condition is characterized by the accumulation of mucopolysaccharides in the stroma, leading to a grayish, cloudy appearance of the cornea that often begins in the area of Bowman's layer.

In the case of granular dystrophy, the opacities appear as discrete gray-white granules in the corneal stroma and do not primarily start in Bowman's layer; rather, they are more typically seen in the corneal stroma itself. Lattice dystrophy is distinguished by its characteristic lattice-like lines within the corneal stroma and is also different in terms of its presentation, which typically does not start in Bowman's layer. Fuchs' dystrophy primarily affects the corneal endothelium and typically results in edema and guttata formation rather than an opacity beginning in the central area of Bowman's layer.

Thus, the defining feature of macular dystrophy being associated with dense gray opacities starting in Bowman's layer makes it the correct answer in this scenario.