KEY FACTS Terminology Definition: Malignant primary retinal neoplasm Trilateral/quadrilateral retinoblastoma (RB): Bilateral ocular RB + pineal ± suprasellar tumors You’re Reading a Preview Become a Clinical Tree membership for Full access and enjoy Unlimited articles Become membership If you are a member. Log in here
KEY FACTS Terminology Optic nerve sheath meningioma a.k.a. perioptic meningioma Benign, slow-growing tumor of optic nerve sheath Distinct entity from intracranial (sphenoorbital) meningioma that extends through orbital apex You’re Reading a Preview Become a Clinical Tree membership for Full access and enjoy Unlimited articles Become membership If you are a member. Log in here
KEY FACTS You’re Reading a Preview Become a Clinical Tree membership for Full access and enjoy Unlimited articles Become membership If you are a member. Log in here
KEY FACTS Imaging MR findings Focal or segmental T2 hyperintensity of optic nerve Central or diffuse optic nerve enhancement Optic nerve diffusely & mildly enlarged Increased diffusivity (diffusion restriction) on DWI sequence due to disruption of myelinated axons You’re Reading a Preview Become a Clinical Tree membership for Full access and enjoy Unlimited articles Become membership If you are a member. Log in here
KEY FACTS Terminology Synonyms: Graves ophthalmopathy, thyroid eye disease Definition: Autoimmune orbital inflammation associated with autoimmune thyroid dysfunction You’re Reading a Preview Become a Clinical Tree membership for Full access and enjoy Unlimited articles Become membership If you are a member. Log in here
KEY FACTS Terminology Nonspecific orbital inflammation, not due to any known etiology or systemic illness You’re Reading a Preview Become a Clinical Tree membership for Full access and enjoy Unlimited articles Become membership If you are a member. Log in here
KEY FACTS Terminology Preseptal cellulitis Infection limited to superficial periorbita Intraorbital (postseptal) cellulitis Infection posterior to orbital septum Orbital septum Connective tissue plane that acts as diaphragm You’re Reading a Preview Become a Clinical Tree membership for Full access and enjoy Unlimited articles Become membership If you are a member. Log in here
KEY FACTS Terminology Definition: Purulent accumulation between bony orbital wall & orbital periosteum You’re Reading a Preview Become a Clinical Tree membership for Full access and enjoy Unlimited articles Become membership If you are a member. Log in here
KEY FACTS Terminology Venous vascular malformation of orbit characterized by endothelial-lined cavernous spaces Pseudoencapsulated morphology distinguishes orbital cavernous venous malformation from venous malformations elsewhere in head & neck Synonymous with cavernous "hemangioma" (misnomer) You’re Reading a Preview Become a Clinical Tree membership for Full access and enjoy Unlimited articles Become membership If you are a member. Log in here
KEY FACTS Terminology Definition: Congenital vascular malformation with variable lymphatic and venous vascular elements You’re Reading a Preview Become a Clinical Tree membership for Full access and enjoy Unlimited articles Become membership If you are a member. Log in here
KEY FACTS Terminology Congenital orbital ectodermal inclusion lesion resulting in choristomatous cyst Dermoid : Includes dermal appendages Epidermoid : Dermal adnexal structures absent You’re Reading a Preview Become a Clinical Tree membership for Full access and enjoy Unlimited articles Become membership If you are a member. Log in here
KEY FACTS Terminology Coloboma = gap or defect of ocular tissue May involve any or all structures of embryonic cleft Types of posterior coloboma Optic disc coloboma Choroidoretinal coloboma Related but distinct anomalies Morning glory disc anomaly Peripapillary staphyloma You’re Reading a Preview Become a Clinical Tree membership for Full access and enjoy Unlimited articles Become membership If you are a member. Log in here
Imaging Approach and Indications Imaging of the orbit encompasses 2 clinically distinct areas of ophthalmology. Eye (or globe) Bony orbit, soft tissues, and periorbita Lesions in these 2 areas result in specific clinical profiles. When a patient is referred for imaging, it is usually clear to the clinician whether the problem involves the globe vs. some other structure of the orbit. The term "orbital" refers to…
KEY FACTS Imaging Arises from maxilla, nasal septum, and skull base Nasal septum location: Posterosuperior vomer Bone CT: Chondroid matrix calcification and narrow bony transition zone 50% with chondroid matrix MR: Increased (high) signal on T2 images and heterogeneous enhancement You’re Reading a Preview Become a Clinical Tree membership for Full access and enjoy Unlimited articles Become membership If you are a member. Log in here
KEY FACTS Terminology Malignant salivary type of adenocarcinoma You’re Reading a Preview Become a Clinical Tree membership for Full access and enjoy Unlimited articles Become membership If you are a member. Log in here
KEY FACTS Terminology Rare, aggressive, sinonasal nonsquamous cell epithelial or nonepithelial malignant neoplasm of varying histogenesis You’re Reading a Preview Become a Clinical Tree membership for Full access and enjoy Unlimited articles Become membership If you are a member. Log in here
KEY FACTS Terminology Sinonasal non-Hodgkin lymphoma: Extranodal lymphoproliferative malignancy You’re Reading a Preview Become a Clinical Tree membership for Full access and enjoy Unlimited articles Become membership If you are a member. Log in here
KEY FACTS You’re Reading a Preview Become a Clinical Tree membership for Full access and enjoy Unlimited articles Become membership If you are a member. Log in here
KEY FACTS Terminology Malignant neoplasm with glandular differentiation arising from surface epithelium or minor salivary rests You’re Reading a Preview Become a Clinical Tree membership for Full access and enjoy Unlimited articles Become membership If you are a member. Log in here
KEY FACTS Terminology Malignant neuroectodermal tumor arising from olfactory neuroepithelium in superior nasal cavity You’re Reading a Preview Become a Clinical Tree membership for Full access and enjoy Unlimited articles Become membership If you are a member. Log in here