Introduction
Seen ~20-30 years and often in females. It has an unknown aetiology. It is classically unilateral.
Differentials include:
- Intraocular tumours + calcification
- Amelanotic choroidal melanoma/naevus
- Melastatic choroidal carcinoma
- Circumscribed choroidal haemangioma
- Disciform macular degeneration
- Posterior scleritis
- Retinoblastoma
Dead Giveaways
Some features:
Diffuse mottled appearance with RPE degeneration over yellowish lesion
Has well defined scalloped margins
Mostly posterior pole or peripapillary
Gradual vision loss if macular involved and VF changes
May lead to secondary choroidal neovascularisation.
Irregular bone spicules surrounded by areolar stroma and large vascular channels
Fundus Red Separation:
2 = Red separated. 3 = Green separated. Indicates the presence of the osteoma in the choroid
OCT:
Appears as hyper-reflective material in the choroid, blocking transmission, and slightly elevating the retina
Note the matter in the choroid, pushing upwards
Ultrasound:
Will display a hyper-reflective region indicating where the osteoma is, however, will block the transmission of ultrasound, leaving a shadow
diagnostic features
Requires monitoring.
Has ossifying tissue which replaces the choroid
