On B-scan ultrasonography, a highly reflective, acoustically dense lesion is noted attached to the optic disc, casting an acoustic shadow. The lesion shows no after-movement. The MOST likely diagnosis is:

• A Optic disc drusen ✓
• B Choroidal melanoma
• C Retinoblastoma with calcification
• D Choroidal osteoma

Explanation

Optic disc drusen appear on B-scan as hyperechoic (highly reflective) calcified deposits at the optic disc that cast posterior acoustic shadowing. They lack after-movement, confirming a solid calcified lesion. Choroidal melanoma shows medium internal reflectivity with choroidal excavation and no calcification. Retinoblastoma with calcification does show high reflectivity and shadowing but is typically an intraocular mass in children. Choroidal osteoma appears as a highly reflective plaque in the posterior pole but is not confined to the disc.

Reference: Khurana Comprehensive Ophthalmology, 7th ed.

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Written and medically reviewed by the StethoPrep medical team.