ENDOC- Pituitary

Question 1

What are the parts of Anterior pituitatry gland?

Answer 1

Pars tuberalis

pars intermedia

Pars distalis

Question 2

What are the parts of the posterior pituitary gland?

Answer 2

infundibulum

pars nervosa

Question 3

Question 4

Question 5

Answer 5

Suprasellar

Question 6

• 10% to 15% of all intracranial tumors
• Most common sellar masses.
• Microadenomas (<10 mm)
• ** Macro**adenomas (>10 mm)
• 75% are hormonally active
  
  • ◦Mostly microadenomas.
• 25% are non-secreting adenomas
  
  • ◦Mostly macroadenomas.
• MRI
  
  • ◦Imaging modality of choice
• ◦

Answer 6

Pituitary Adenomas

Question 7

Pituitary adenomas being how many times more common than craniopharyngiomas and Rathke’s cleft cysts.

Answer 7

five times

Question 8

75% of Pituitary adenoma are hormonally active

Answer 8

◦Mostly microadenomas.

Question 9

Pituitary Adenomas

25% are non-secreting adenomas

◦

Answer 9

◦Mostly macroadenomas.

Question 10

What is the imaging of choice for pituitary adenoma?

Answer 10

MRI
◦Imaging modality of choice

Question 11

Easily visualized on MRI.

• • >10 mm**
• • Most commonly manifest** because of optic chiasm or nerve compression, hydrocephalus, cranial nerve palsies, or anterior pituitary dysfunction.

Answer 11

Macroadenomas

Question 12

What is the Imaging findings of Macroadenomas?

Answer 12

** Isointense** to gray matter on T1WI

Question 13

Answer 13

Pituitary Macroadenoma

Question 14

Answer 14

Precontrast (A) and postcontrast (B) coronal T1WI show enhancing mass (arrows) extending (arrowheads) beyond lateral margin of cavernous sinus and flow voids of left internal carotid artery.

Question 15

Arise from **squamous epithelial remnants of the anterior lobe of the pituitary gland **

◦Derived from the pars tuberalis
◦Usually symptomatic
◦Most common suprasellar mass in the pediatric population
◦

Answer 15

Craniopharyngiomas

Question 16

What is the peak of age of craniopharyngioma?

Answer 16

peak incidence between 5 and 10 years of age, with a second peak seen between the ages of 50 and 60 years.

Question 17

◦“Crank-case oil” appearance

Answer 17

Craniopharyngioma

Question 18

Craniopharyngioma is Cranio symptomtic because of a larger size

Most craniopharyngiomas involve_____________(70%),

Solid and cystic components are typical with the fluid of the cyst often containing cholesterol crystals and grossly having the appearance of “crank-case oil.”

Answer 18

both intrasellar and suprasellar compartments

Question 19

What are the typical components of the fluid of the cyst of craniopharyngioma?

Answer 19

Solid and cystic components are typical with the fluid of the cyst often containing cholesterol crystals and grossly having the appearance of “crank-case oil.”

Question 20

What is the Imaging Finding in MRI?

Answer 20

Cystic mass with mural node
** Calcification (children)**
Enhancement of the solid rim, but not of the cystic part
Obstruction of the Foramen of Monroe
◦Hydrocephalus

Question 21

How much is the incidence percent of cystic mass in craniopharyngioma?

Answer 21

Cystic mass 90%

cAlcification less in aduts

Question 22

Answer 22

Craniopharyngioma

• Fig.5.42a: Typical craniopharyngioma at frontal and lateral MRI scan. The yellow arrows point to the cyst, the red to the solid part of the tumor and the blue to a dilated lateral ventricle (hydrocephalus).

Cystic mass with mural node

Calcification (children)

Enhancement of the solid rim, but not of the cystic part

Obstruction of the Foramen of Monroe

Hydrocephalus

Question 23

◦Arises from the embryologic remnant of Rathke’s pouch.

• *◦Rathke’s pouch**: rostral outpouching during the 4th week of embryogenesis; precursor of anterior lobe and pars intermedia of pituitary gland.
• *◦Arising from the pars intermedia.**

Answer 23

Rathke’s Cleft Cyst

Question 24

Majority of Rathke’s Cleft Cyst Could be __________comprising - 70%

Answer 24

both sellar and suprasellar

Question 25

Rathke’s Cleft Cyst \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_ – 20%

Answer 25

Purely intrasellar

Question 26

Rathke’s Cleft Cyst What is the finding in CT scan?

Answer 26

CT scan: **◦Hypodense** , with **possible rim enhancement**

Question 27

What is the finding of Rathke's cleft in MRI?

Answer 27

MRI: **◦Hyperintense relative to brain in T1WI ◦Variable signal in T2WI**

Question 28

Differentiate the MRI finding of T1 vs T2 The signal characteristics vary according to the cyst composition which may be **mucoid or serous. **

Answer 28

**T1** * 50% are hyperintense (high protein content) * 50% are hypointense **T2** * 70% are **hyperintense** * 30% are iso or hypointense

Question 29

Imaging Finding: MRI

Answer 29

MRI The signal characteristics vary according to the cyst composition which may be mucoid or serous. T1 * 50% are hyperintense (high protein content) * 50% are hypointense T2 * 70% are hyperintense * 30% are iso or hypointense

Question 30

Imaging Finding: CT Scan

Answer 30

Midline cyst within the sella **Non contrast**: it is **typically non-calcified** and of **homogenous low** attenuation. **Uncommonly it may be of mixed iso- and low-attenuation,** or contain small curvilinear calcifications in the wall (seen in 10-15% of cases). **Post contrast:** typically **non enhancing although the cyst wall may enhance in some cases 8.**

Question 31

Answer 31

Midline cyst within the sella Non contrast: it is typically non-calcified and of homogenous low attenuation. Uncommonly it may be of mixed iso- and low-attenuation, or contain small curvilinear calcifications in the wall (seen in 10-15% of cases). Post contrast: typically non enhancing although the cyst wall may enhance in some cases 8.

Question 32

* * Defect in the **sella diaphragm** wit**h extension of CSF into the sella** * Common anatomic variant * **10% in adults** * ** Incidental finding** * ** Asymptomatic** * NO clinical significance

Answer 32

Empty Sella

Question 33

Answer 33

Empty Sella