Optos color RG imaging shows a yellowish, well-circumscribed amelanotic lesion centered in the inferonasal macula. On OCT, the lesion has an internal lamellar, sponge-like architecture, characterized by horizontal hyporeflective lines corresponding to intralesional vascular channels and bony trabeculae. The overlying RPE and retina appear fairly normal. The lesion is markedly hyperreflective on B-scan ultrasonography with posterior acoustic shadowing.
Learning Points:
Choroidal osteoma is a rare, benign ossifying choroidal tumor that typically affects young women, often in the peripapillary or macular region. Typical features include a clinical yellowish-orange lesion, a hyperreflective choroidal mass with a lamellar or trabecular internal architecture on OCT, and, most importantly, marked posterior acoustic shadowing on B-scan ultrasonography due to calcification. These imaging characteristics are distinct from those of other choroidal lesions, such as melanoma or hemangioma, which lack dense calcification and exhibit different reflectivity patterns.
Although benign, choroidal osteoma may cause vision loss from macular neovascularization (MNV), subretinal fluid, and progressive decalcification with atrophy of the retinal pigment epithelium and outer retinal layers. MNV can be successfully treated with anti-VEGF therapy (see Seong et al, Graefe’s 2022;250:1713-1721).
