Board Certified Ophthalmologist Oculoplastics and Orbital Disease 1 — Questions and Answers
Question 1: Which of the following is the most common primary malignant orbital tumor in adults?
- Lymphoma (Correct answer)
- Rhabdomyosarcoma
- Capillary hemangioma
- Optic nerve glioma
Correct answer: Lymphoma
Orbital lymphoma (most often B-cell non-Hodgkin) is the most common primary malignant orbital tumor in adults.
Question 2: A child presents with proptosis, erythema, and restricted ocular motility following a sinus infection. CT shows subperiosteal abscess. What is the most appropriate next step?
- IV antibiotics and surgical drainage (Correct answer)
- Oral antibiotics alone
- Topical steroids
- Observation for 48 hours
Correct answer: IV antibiotics and surgical drainage
A subperiosteal abscess (Chandler stage IV orbital cellulitis) requires prompt IV antibiotics and surgical drainage to prevent vision loss and intracranial spread.
Question 3: Which muscle is most commonly entrapped in a blowout fracture of the orbital floor?
- Inferior rectus (Correct answer)
- Medial rectus
- Superior oblique
- Inferior oblique
Correct answer: Inferior rectus
The inferior rectus muscle and its surrounding connective tissue are most commonly entrapped in orbital floor blowout fractures, causing restricted upgaze.
Question 4: What is the hallmark finding on CT that distinguishes thyroid eye disease (Graves' orbitopathy) from orbital lymphoma?
- Fusiform enlargement of extraocular muscles sparing the tendons (Correct answer)
- Irregular soft tissue mass with bone destruction
- Enhancement of the lacrimal gland
- Diffuse orbital fat stranding
Correct answer: Fusiform enlargement of extraocular muscles sparing the tendons
Thyroid eye disease characteristically causes fusiform enlargement of extraocular muscle bellies while sparing the tendons, unlike most other orbital masses.
Question 5: A patient presents with a painless, slowly progressive unilateral proptosis. MRI shows a well-circumscribed intraconal mass with homogeneous enhancement. What is the most likely diagnosis?
- Cavernous hemangioma (cavernous venous malformation) (Correct answer)
- Orbital varix
- Optic nerve sheath meningioma
- Metastatic lesion
Correct answer: Cavernous hemangioma (cavernous venous malformation)
Cavernous hemangioma (cavernous venous malformation) is the most common benign orbital tumor in adults and presents as a well-circumscribed intraconal mass with homogeneous enhancement.
Question 6: Which eyelid position abnormality is characterized by the upper eyelid margin resting at or below the superior pupillary border with normal levator function?
- Blepharoptosis (Correct answer)
- Dermatochalasis
- Blepharospasm
- Lagophthalmos
Correct answer: Blepharoptosis
Blepharoptosis is defined as drooping of the upper eyelid margin to or below the superior pupil, and can occur with normal levator function in aponeurotic defects.
Board Certified Ophthalmologist Oculoplastics and Orbital Disease 1
Which of the following is the most common primary malignant orbital tumor in adults?