Key points Definition: Orbital lipomas (OL) are very rare tumors that are usually benign, accounting for less than 1% of orbital tumors. Classic clue: The patient presents with a well-circumscribed homogeneous orbital mass with low attenuation approximating orbital fat, having…
Key points Definition: Dermoids originate from totipotential germ cells. Present at birth, these differentiate abnormally, developing characteristics of mature dermal cells. Synonym: Orbital dermoids, retrobulbar orbital dermoids, or deep dermoids. Classic clue: Well-circumscribed encapsulated mass with low Hounsfield numbers, filled…
Key points Definition: Optic nerve meningioma (ONM) is a rare, benign tumor arising from arachnoid cap cells in meninges covering the optic nerve (ON). Synonym: Optic nerve sheath meningioma (ONSM). Classic Clue: Appears as an enhancing mass surrounding the nonenhancing…
Key points Definition: Optic nerve glioma (ONG) is a type of juvenile pilocytic astrocytoma (grade 1 astrocytoma) that occurs more commonly in children and young adults. Synonym: Optic pathway glioma (OPG). Classic clue: Sausage-shaped diffuse fusiform enlargement and “kinking” of…
Key points Definition: Orbital cavernous hemangioma is a benign, slow-growing, vascular lesion manifesting as painless, progressive proptosis. Synonyms: Ocular cavernous hemangioma, orbital cavernous malformation, orbital cavmal. Classic clue: Well-circumscribed, enhancing intraconal mass in adult patients. Usual imaging appearance Computed tomography…
Key points Definition: Retinal detachment (RD) is a condition in which the inner retinal layer peels away from the middle choroidal layer of the globe permitting fluid to accumulate in what was previously only a “potential space.” It is a…
Key points Definition: An ocular prosthesis (OP) is a device that replaces the native eye after enucleation, evisceration, or exenteration. Also known as: glass eye, artificial eye. Classic clue: The patient usually visits the radiology department for neuro computed tomography…
Key points Definition: Phthisis bulbi (PB) is a generic descriptive term for the ocular globe’s “end-stage” appearance after wasting away, becoming anatomically disfigured, and shrunken as a result of a range of possible prior insults. Also known as: end-stage eye,…
Key points Definition: Ruptured globe (RG) occurs when the integrity of the eye is breeched by blunt or penetrating trauma causing full-thickness corneal or scleral breech. This is an ophthalmologic emergency. Synonym: Shattered globe. Classic clue: A man in his…
Key points Definition: Ocular lens displacement (OLD) refers to the malposition of the lens relative to its normal location as a result of disruption of the zonular fibers, which normally connect the lens to the ciliary body. Synonyms: Lens luxation,…