25.3

Question 1

What is the major imaging modality for the head and neck?

Answer 1

CT - can image soft tissues/muscle/fat, bones, orbits

Question 2

What is the major disadvantage of CT?

Answer 2

Ionising radiation
Irradiation can cause cataracts
Radiation can induce malignancy in the thyroid because thyroxine absorbs radiation

Question 3

Infections or tumours usually respect ___ planes.

Answer 3

Fascial - so they extend up and down spaces, and not usually across

Question 4

___ fat space between muscles can be helpful in identifying or localising masses if it has been displaced.

Answer 4

Parapharyngeal fat space

Question 5

___ is best for the brain and spinal cord, but poor for bone.

Answer 5

MRI

Question 6

On T2 weighted MRI, CSF appears ___.

Answer 6

Bright

Question 7

On T2 weighted MRI, the grey matter appears ___ and the white matter appears ___. This is opposite in T1 weighted MRI!

Answer 7

T2 - grey matter is bright and white matter is dark

T1 - grey matter is dark and white matter is bright

Question 8

Fibrous dysplasia that affects the mandible is also called ___.

Answer 8

Cherubism

Question 9

The two main types of thyroid cancer are:

Answer 9

Papillary - usually to lymph nodes

Follicular - usually haematogenous, can cause haemorrhagic cerebral metastases

Question 10

How could you differentiate between meningeal arteries and superficial temporal arteries on angiography?

Answer 10

The meningeal arteries are in the meninges/skull so they do not move and are straight.
The superficial temporal arteries are in the skull and mobile, so they are tortuous so they can stretch.