Non-Functioning Tumours and Pituitary Hormone Testing

Question 1

Anterior pituitary lobe: glandular tissue, accounts for ___ % of total weight.

Answer 1

75

Question 2

what does the posterior pituitary contain anatomically

Answer 2

nerve tissue & contains axons that originate in the hypothalamus.

Question 3

what is a Craniopharyngioma
* benign of malignant
* peak ages
* symptoms

Answer 3

Benign tumour - infiltrates surrounding structures
Peak ages: 5 to 14 years; 50 to 74 years
Raised ICP, visual disturbances, growth failure, pituitary hormone deficiency, weight increase

Question 4

Describe Rathke’s Cyst
* what is it derived from
* structure
* symptoms

Answer 4

• Derived from rathkes cyst
• Single layer of epithelial cells with mucoid, cellular, or serous components in cyst fluid
• mostly asymptomatic but presents with headache and amenorrhoea, hypopituitarism and hydrocephalus

Question 5

What is a Meningioma
* what its a complication of
* symptoms

Answer 5

• complication of radiotherapy
• Usually present with loss of visual acuity, endocrine dysfunction and visual field defects

Question 6

what is an example lesion of bitemporal haemiopeia

Answer 6

Compression of optic chiasm by pituitary tumour

Question 7

How would you test non functionoins pituitary tumours

Answer 7

• No specific test but absence of hormone secretion
• Test normal pituitary function
• Trans-sphenoidal surgery if threatening eyesight or progressively increasing in size

Question 8

Argue MRI vs CT for scanning pituitary

Answer 8

MRI
* Preferred imaging study for the pituitary

• ** Better visualization of soft tissues **and vascular structures than CT
• No exposure to **ionizing radiation **
• T1-weighted images produce high–signal intensity images of fat. Structures such as fatty marrow and orbital fat show up as bright images.
• T2-weighted images produce high-intensity signals of structures with high water content, such as cerebrospinal fluid and cystic lesions

CT
* Better at visualizing bony structures and calcifications within soft tissues

• Better at determining diagnosis of tumors with calcification, such as germinomas, craniopharyngiomas, and meningiomas
• May be useful when MRI is contraindicated, such as in patients with** pacemakers or metallic implants** in the brain or eyes
• less optimal soft tissue imaging compared to MRI
• use of intravenous contrast media
• exposure to radiation