Key points Definition: Esthesioneuroblastoma (ENB) is a rare neuroendocrine malignancy of neural crest origin arising from olfactory epithelium near the cribriform plate and the nearby nasal cavity. ENB may invade the orbit, causing ophthalmic signs and symptoms. Synonym: Olfactory neuroblastoma.…
Key points Definition: Isolated metastasis to the optic nerve is rare and is often overlooked or misdiagnosed initially. Classic clue: Typically, a middle-aged female presents with “a little blurred vision,” further inquiry identifies pain, proptosis, reduced visual acuity, and bitemporal…
Key points Definition: Leukemia presenting as an orbital mass portends a more serious prognosis as these patients continue to show significantly lower survival rates than other leukemia patients. Synonym: A subset of orbital leukemia includes: granulocytic sarcoma, chloroma, or myeloid…
Key points Definition: Retinoblastoma (RB) is a rapidly developing intraocular cancer arising from immature retinal cells. Classic clue: A calcified posterior globe mass in an infant or young child is an RB until proved otherwise. RB is the most common…
Key points Definition : Ocular melanoma is the most common intraocular malignancy in adults. Synonyms : Orbital melanoma, uveal melanoma, choroidal melanoma. Classic clue: A “collar button” enhancing intraocular mass in adults. Computed tomography (CT) shows: Ocular melanoma is hyperdense.…
Key points Definition: Ocular adnexal lymphoma (OAL) is one of the most common orbital tumors in adults, accounting for 50% of orbital malignancies. Synonym: Orbital lymphoma (OL). Classic clue: An older patient presenting with an orbital mass causing progressive exophthalmos,…
Key points Definition: Usually found in middle-aged adults, orbital schwannomas (OS) are well-defined, encapsulated, slowly growing benign tumors arising from peripheral nerve Schwann cells, and comprise 1% to 2% of orbital tumors. Classic clue: Middle-aged patient presenting with optic neuropathy,…
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…