ENDOC- Pituitary Flashcards
What are the parts of Anterior pituitatry gland?
Pars tuberalis
pars intermedia
Pars distalis
What are the parts of the posterior pituitary gland?
infundibulum
pars nervosa



Suprasellar
- 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
- ◦
Pituitary Adenomas
Pituitary adenomas being how many times more common than craniopharyngiomas and Rathke’s cleft cysts.
five times
75% of Pituitary adenoma are hormonally active
◦Mostly microadenomas.
Pituitary Adenomas
25% are non-secreting adenomas
◦
◦Mostly macroadenomas.
What is the imaging of choice for pituitary adenoma?
MRI
◦Imaging modality of choice
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
What is the Imaging findings of Macroadenomas?
** Isointense** to gray matter on T1WI

Pituitary Macroadenoma

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.
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
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.
◦“Crank-case oil” appearance
Craniopharyngioma
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
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.”
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
How much is the incidence percent of cystic mass in craniopharyngioma?
Cystic mass 90%
cAlcification less in aduts

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
◦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
Majority of Rathke’s Cleft Cyst Could be __________comprising - 70%
both sellar and suprasellar
Rathke’s Cleft Cyst
_______________ – 20%
Purely intrasellar
Rathke’s Cleft Cyst
What is the finding in CT scan?
CT scan:
◦Hypodense , with possible rim enhancement
What is the finding of Rathke’s cleft in MRI?
MRI:
◦Hyperintense relative to brain in T1WI
◦Variable signal in T2WI
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
Imaging Finding: MRI

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
Imaging Finding: CT Scan

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.

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.
- 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

Empty Sella