Globe and Orbital pathology

Question 1

Orbital pathology

Relevance of DWI and enhancement

Answer 1

Measure the ADC

Question 2

Orbital cellulitis

Differentiating infectious vs inflammatory on imaging

Answer 2

Posterior scleritis seen more likely in inflammatory cause.
- usually no fever, sinusitis

Usually not present on infectious cellulitis

Otherwise will look the same

Question 3

Imaging protocol for GLOBE

Answer 3

Question 4

Imaging features of scleritis?

Answer 4

If choroid pushed forwards - a sign that mass/inflammation in sclera

Mets and inflammation can cause

Question 5

Uveal melanoma

How to differentiate retinal detachment vs melanoma??

Answer 5

Most common mass of uvea in adults

• Measure ADC
• Mushroom

Differentiating detachment?

Retinal detachment wont enhance and wont cause DWI

Question 6

Thickened enhancing choroid/uvea

Differential?

Answer 6

Lymphoma vs uveitis

DWI in lymphoma

Question 7

Optic neuritis DDx

Answer 7

Main differential is ischaemic

Neuritis causes
- MS, NMO

Optic perineutisi can be seen in inflammatory conditions e.g. sarcoid

Question 8

Extraconal mass of orbit

What to think of?

Answer 8

Question 9

Intraconal fat DDx masses

Answer 9

Question 10

Lacrimal gland tumours

DDx

Answer 10

Other unilateral lesions

-pseudotumour
pleomorphic adenoma
-adenoid cystic and look for PNS

Bilateral

Lymphoma (lower ADC) vs inflammatory (sjogrens, sarcoid, IgG4)

Question 11

Orbital sarcoidosis

What are two key features?

Answer 11

Question 12

Orbital IgG4 disease

What are features?

Is it painful?

Answer 12

Also don’t forget Wegners with orbital involvement. Can be bilateral. Look for nasal septum destruction.

Question 13

DDx

Periscleritis
Perineuritis optic nerve
Orbital myositis

Answer 13

Graves disease is the main cause of orbital myositis

Question 14

IBD related orbital disorders

What are 3?

Answer 14

Orbital myositis
Dacroadenitis
Posterior scleritis

Question 15

IgG4 disease

Second most common in H&N

Where are most cases in H&N?

Answer 15

Combined diagnostic criteria: clinical features, serum IgG4 levels (over 40% ratio to IgG+ plasma cells)

Diagnostic imaging is not part of criteria - appearances are non specific

Most common places in H&N

• Submandibular gland (most commonly involved salivary gland)
• Can be multi salvary gland involvement)
• Orbit (lacrimal - most common involved in orbit, and extraocular muscles)
• Paranasal sinuses and nose

DDx

Lacrimal gland enlargement and inflammation with low ADC - lymphoma

Low ADC in both IgG4 and Lymphoma