ENDOC- Pituitary Flashcards Preview

Diagnostic Imaging > ENDOC- Pituitary > Flashcards

Flashcards in ENDOC- Pituitary Deck (33):
1

What are the parts of Anterior pituitatry gland?

Pars tuberalis

pars intermedia

Pars distalis

2

What are the parts of the posterior pituitary gland?

infundibulum

pars nervosa

3

Q image thumb

4

Q image thumb

5

Q image thumb

Suprasellar

6

 

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

  •  

Pituitary Adenomas

7

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

  five times

8



 75% of Pituitary adenoma are hormonally active

 

◦Mostly microadenomas.

9

Pituitary Adenomas

 

 25% are non-secreting adenomas



 

◦Mostly macroadenomas.

10

What is the imaging of choice for pituitary adenoma?

 MRI
◦Imaging modality of choice

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.
 

Macroadenomas 

12

What is the Imaging findings of Macroadenomas?

 

 Isointense to gray matter on T1WI

13

Q image thumb

Pituitary Macroadenoma

14

Q image thumb

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.

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

 Craniopharyngiomas

16

What is the peak of age of craniopharyngioma?

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

 

17

◦“Crank-case oil” appearance

Craniopharyngioma

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.”

 both intrasellar and suprasellar compartments 

19

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

 

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.”

20

What is the Imaging Finding in MRI?


 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
 

21

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

Cystic mass 90%

cAlcification less in aduts

22

Q image thumb

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

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.
 
 

Rathke’s Cleft Cyst

24

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


 

both sellar and suprasellar

25

 Rathke’s Cleft Cyst

_______________ – 20%

 

 Purely intrasellar

26

 Rathke’s Cleft Cyst

What is the finding in CT scan?
 

CT scan:
◦Hypodense , with possible rim enhancement
 

27

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

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

 

28

Differentiate the MRI  finding of T1 vs T2

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

29

Imaging Finding: MRI

Q image thumb

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

30

Imaging Finding: CT Scan

Q image thumb

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.

31

Q image thumb

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.

32

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

Empty Sella

33

Q image thumb

Empty Sella