Oculoplastic & Orbit Flashcards

Which extraocular muscle is most commonly enlarged in thyroid eye disease?

Answer: Inferior rectus

The inferior rectus is most frequently involved, followed by the medial, superior, and lateral recti.

On orbital CT, enlargement of an extraocular muscle that includes the tendon insertion is most characteristic of which condition?

Answer: Idiopathic orbital myositis

Orbital myositis typically involves the tendon, whereas thyroid eye disease classically spares it.

What is the most common benign orbital mass in adults?

Answer: Cavernous venous malformation (cavernous hemangioma)

Cavernous venous malformation is the most common benign orbital lesion in adults, typically a well-circumscribed intraconal mass in middle-aged women.

A 7-year-old presents with rapidly progressive unilateral proptosis and superior orbital mass over 2 weeks. What is the most likely primary orbital malignancy?

Answer: Rhabdomyosarcoma

Rhabdomyosarcoma is the most common primary orbital malignancy of childhood and often presents with rapid proptosis, frequently superonasally.

What is the current first-line systemic treatment for a periocular infantile hemangioma causing amblyopia risk?

Answer: Oral propranolol

Oral propranolol has replaced corticosteroids as first-line systemic therapy for vision-threatening infantile hemangiomas.

An S-shaped upper eyelid deformity with a 'bag of worms' palpable texture is most characteristic of which lesion?

Answer: Plexiform neurofibroma

Plexiform neurofibroma, pathognomonic of neurofibromatosis type 1, produces an S-shaped lid and a 'bag of worms' feel.

A 'tram-track' pattern of calcification along the optic nerve on CT is most suggestive of which diagnosis?

Answer: Optic nerve sheath meningioma

Optic nerve sheath meningioma shows tubular enhancement or calcification of the sheath around a spared nerve, producing the tram-track sign.