---
title: "Cystic Intrasellar Mass"
docid: "e5a24511-dd27-495c-b20a-c56534351a06"
authors:
- key: "8d5254e9-8dda-478b-8f08-bdee97a32c79"
value: "Karen L. Salzman, MD, FACR"
- key: "5cff4116-3654-4b3a-bb75-5ebe0b8c9850"
value: "Anne G. Osborn, MD, FACR"
breadcrumbs:
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name: "Brain"
slug: "brain"
treeNodeId: "6d8829f1-14d7-45af-8675-255189aa526a"
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name: "Differential Diagnosis"
slug: "differential-diagnosis"
treeNodeId: "a7fdd139-664e-4bb8-8d18-400e4733ff60"
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name: "Sella/Juxtasellar, Pineal Region"
slug: "sellajuxtasellar-pineal-region"
treeNodeId: "5e38b9c1-3137-47e3-aa83-1fc82cb4099a"
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name: "Anatomically Based Differentials"
slug: "anatomically-based-differentials"
treeNodeId: "7a51b2ca-8fee-4c16-aff3-b7189f68ea60"
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name: "Cystic Intrasellar Mass"
slug: "cystic-intrasellar-mass"
treeNodeId: null
category: "Brain"
documentVersionId: "853dca59-915a-4a45-8c80-d20bbbfd9733"
imageCount: 23
lastUpdated: "01/24/23"
pageDescription: "Cystic Intrasellar Mass"
pageKeywords: "Brain, Differential Diagnosis, Sella/Juxtasellar, Pineal Region, Anatomically Based Differentials, Cystic Intrasellar Mass"
pageTitle: "Cystic Intrasellar Mass | STATdx"
enhancedTitle: "Cystic Intrasellar Mass"
type: "DDX"
references: true
breadcrumbs:
- "Brain"
- "Differential Diagnosis"
- "Sella/Juxtasellar, Pineal Region"
- "Anatomically Based Differentials"
- "Cystic Intrasellar Mass"
---
# ESSENTIAL INFORMATION
- ## Key Differential Diagnosis Issues
- Cystic mass originating **within** sella turcica vs. intrasellar extension from suprasellar lesion
- Intrasellar extension of suprasellar lesion > intrasellar mass
- ## Helpful Clues for Common Diagnoses
- **Empty Sella**
- Small crescent of compressed pituitary gland lines bottom of sella turcica
- Primary empty sella considered normal variant
- Secondary = surgery, pituitary infarction
- **Intracranial****H****ypertension, Idiopathic**
- Pseudotumor cerebri: F > > M
- Empty sella ± dilated optic nerve sheaths, small ventricles, transverse sinus/sigmoid sinus junction stenosis
- Obese female with headaches
- **Cystic Pituitary Adenoma**
- May be functional, often prolactinoma, or null cell
- Small (≤ 10 mm), enhances < gland
- ## Helpful Clues for Less Common Diagnoses
- **Rathke Cleft Cyst**
- Usually < 1 cm; may be giant, erode sella
- 40-75% have intracystic nodule
- ± claw sign (enhancing rim of pituitary around nonenhancing cyst)
- **Craniopharyngioma**
- Truly intrasellar craniopharyngioma rare
- If no Ca⁺⁺, difficult to distinguish from Rathke cleft cyst
- 90% rule (adamantinomatous): 90% calcify, 90% cystic, 90% enhance
- ## Helpful Clues for Rare Diagnoses
- **Pituitary****A****poplexy**
- Can be life threatening (secondary to pituitary insufficiency)
- Acutely may present as necrotic, rim-enhancing mass
- Typically sellar and suprasellar
- **Arachnoid Cyst**
- Truly intrasellar arachnoid cyst (AC) rare
- Usually extension from suprasellar AC
- **Neurocysticercosis Cyst**
- Suprasellar cysts → intrasellar
- May have racemose cysts in basal cisterns
- **Epidermoid Cyst**
- Suprasellar < off-midline location
- T2 hyperintense, DWI hyperintense
- **Saccular Aneurysm****(Thrombosed)**
- Medially projecting from cavernous ICA
- If thrombosed, may appear low signal intensity on T1 C+ scans
- **Par Intermedia Cyst**
- Benign cyst in between adenohypophysis and neurohypophysis
- **Obstructive Hydrocephalus (Mimic)**
- Anterior recesses of 3rd ventricle enlarge
- Herniate inferiorly into sella
- If chronic may expand, erode bony sella
## References
# Selected References
1. [Kuzan BN et al: Accuracy and reliability of magnetic resonance imaging in the diagnosis of idiopathic intracranial hypertension. Eur J Radiol. 155:110491, 2022](http://www.ncbi.nlm.nih.gov/pubmed/?term=36007323%5Bpmid%5D)
1. [Azuma M et al: Added value of contrast-enhanced 3D-FLAIR MR imaging for differentiating cystic pituitary adenoma from Rathke's cleft cyst. Magn Reson Med Sci. 20(4):404-9, 2021](http://www.ncbi.nlm.nih.gov/pubmed/?term=33487606%5Bpmid%5D)
1. [Belachew NF et al: Evolution of MRI findings in patients with idiopathic intracranial hypertension after venous sinus stenting. AJNR Am J Neuroradiol. 42(11):1993-2000, 2021](http://www.ncbi.nlm.nih.gov/pubmed/?term=34620591%5Bpmid%5D)
1. [Azuma M et al: Usefulness of contrast-enhanced 3D-FLAIR MR imaging for differentiating Rathke cleft cyst from cystic craniopharyngioma. AJNR Am J Neuroradiol. 41(1):106-10, 2020](http://www.ncbi.nlm.nih.gov/pubmed/?term=31857323%5Bpmid%5D)
1. [Kuan EC et al: Treatment outcomes of Rathke's cleft cysts managed with marsupialization. J Neurol Surg B Skull Base. 78(2):112-5, 2017](http://www.ncbi.nlm.nih.gov/pubmed/?term=28321372%5Bpmid%5D)
1. [Morris PP et al: Transverse sinus stenosis is the most sensitive MR imaging correlate of idiopathic intracranial hypertension. AJNR Am J Neuroradiol. 38(3):471-7, 2017](http://www.ncbi.nlm.nih.gov/pubmed/?term=28104635%5Bpmid%5D)
1. [Sasagawa Y et al: Clinical characteristics of acromegalic patients with empty sella and their outcomes following transsphenoidal surgery. Pituitary. 20(4):403-8, 2017](http://www.ncbi.nlm.nih.gov/pubmed/?term=28233140%5Bpmid%5D)
1. [Sivaraju L et al: Giant multi-compartmental suprasellar Rathke's cleft cyst with restriction on diffusion weighted images. Neuroradiol J. 1971400916682512, 2017](http://www.ncbi.nlm.nih.gov/pubmed/?term=28059626%5Bpmid%5D)
1. [Zhang X et al: Sellar cysticercosis and septum pellucidum cyst: a case report and review of the literature. Southeast Asian J Trop Med Public Health. 45(3):584-7, 2014](http://www.ncbi.nlm.nih.gov/pubmed/?term=24974642%5Bpmid%5D)
1. [Saindane AM et al: Factors determining the clinical significance of an "empty" sella turcica. AJR Am J Roentgenol. 200(5):1125-31, 2013](http://www.ncbi.nlm.nih.gov/pubmed/?term=23617499%5Bpmid%5D)
1. [Arriada-Mendicoa N et al: Imaging features of sellar cysticercosis. AJNR Am J Neuroradiol. 24(7):1386-9, 2003](http://www.ncbi.nlm.nih.gov/pubmed/?term=12917134%5Bpmid%5D)
## Images
### Selected Images

**Empty Sella**
*Sagittal T1WI MR shows empty sella with herniation of CSF through the diaphragma sellae
, flattening the pituitary gland inferiorly against the sellar floor
. Empty sella may be asymptomatic or may be associated with idiopathic intracranial hypertension.*

**Empty Sella**
*Sagittal T1WI MR shows empty sella with herniation of CSF through the diaphragma sellae
, flattening the pituitary gland inferiorly against the sellar floor
. Empty sella may be asymptomatic or may be associated with idiopathic intracranial hypertension.*

**Intracranial Hypertension, Idiopathic**
*Axial T2WI FS MR in a young female with headaches shows classic features of idiopathic intracranial hypertension with an empty sella
, dilatation of the optic nerve sheaths
, and prominent optic nerve heads
, related to papilledema.*

**Cystic Pituitary Adenoma**
*Coronal T2WI MR shows a cystic microadenoma
in the right pituitary gland. Microadenomas may be asymptomatic or may present with abnormal endocrine values, commonly elevated prolactin. When cystic, microadenomas mimic benign cysts, such as Rathke cleft cysts.*

**Rathke Cleft Cyst**
*Sagittal T1WI C+ MR shows an intrasellar Rathke cleft cyst
as a CSF-like mass that displaces the normal pituitary gland anteriorly
, forming a claw sign. Often, a nonenhancing, intracystic nodule may be seen.*

**Craniopharyngioma**
*Sagittal T2WI MR shows a cystic sellar and suprasellar mass
.Calcification and enhancement help differentiate craniopharyngioma from Rathke cleft cyst. Only 5% of craniopharyngiomas are purely intrasellar.*

**Pituitary Apoplexy**
*Coronal T2WI MR shows a cystic sellar and suprasellar mass
in a 40-year-old male patient with acute onset of headache and cranial neuropathy. Pituitary apoplexy may result from hemorrhage or infarction of a macroadenoma, as in this patient.*

**Arachnoid Cyst**
*Coronal T1WI C+ MR shows a sellar and suprasellar arachnoid cyst
with leftward displacement of the pituitary infundibulum
. Note the pituitary gland
is flattened beneath the cyst. Arachnoid cysts follow CSF signal intensity on all sequences.*

**Obstructive Hydrocephalus (Mimic)**
*Sagittal T2WI SPACE MR shows obstructive hydrocephalus related to a cystic lesion at the anterior cerebral aqueduct
. Note mild enlargement of bony sella
and suprasellar herniation of the anterior 3rd ventricle
.*
### Additional Images

**Arachnoid Cyst**
*Sagittal T1WI MR shows a sellar and suprasellar arachnoid cyst
. Note the pituitary gland
is stretched anteriorly around the cyst. Arachnoid cysts follow CSF signal intensity on all sequences.*

**Epidermoid Cyst**
*Axial T2WI MR shows a large epidermoid cyst extending into the sella and suprasellar subarachnoid space
. Epidermoids are congenital lesions that classically show DWI hyperintensity. They are most commonly found in the cerebellopontine angle.*

**Craniopharyngioma**
*Coronal T2WI MR shows a CSF-like intrasellar mass
. Surgery disclosed intrasellar craniopharyngioma with only a small suprasellar component. Calcification and enhancement help differentiate craniopharyngioma from a Rathke cleft cyst. Only 5% of craniopharyngiomas are purely intrasellar.*

**Obstructive Hydrocephalus (Mimic)**
*Sagittal T2WI MR shows aqueductal stenosis
with severe obstructive hydrocephalus. Note marked enlargement of bony sella
and intrasellar herniation of the inferior 3rd ventricle
.*

**Pituitary Apoplexy**
*Coronal T1WI C+ MR shows rim
and nodular
enhancement around necrotic macroadenoma in a patient with sudden onset of visual problems and pituitary insufficiency.*

**Pituitary Apoplexy**
*Sagittal T1WI MR in a patient with a remote history of pituitary apoplexy caused by Sheehan syndrome shows secondary empty sella
.*

**Saccular Aneurysm (Thrombosed)**
*Axial T1WI C+ FS MR shows pituitary apoplexy mimic. A nonenhancing, cystic-appearing intrasellar mass
was diagnosed as pituitary apoplexy. Thrombosed ICA aneurysm was found at surgery.*

**Empty Sella**
*Sagittal T1WI MR shows empty sella with herniation of CSF through the diaphragma sellae
, flattening the pituitary gland inferiorly against the sellar floor
.*

**Intracranial Hypertension, Idiopathic**
*Axial T2WI MR shows idiopathic intracranial hypertension (pseudotumor cerebri) with empty sella
and dilated optic nerve sheaths
.*

**Rathke Cleft Cyst**
*Coronal T1WI MR shows an intrasellar Rathke cleft cyst
, seen here as a CSF-like mass that displaces the pituitary gland inferiorly and laterally around it.*

**Neurocysticercosis Cyst**
*Sagittal T1WI C+ MR shows suprasellar racemose neurocysticercosis (NCC) cysts
extending into sella turcica
, flattening pituitary gland against sellar floor
.*

**Neurocysticercosis Cyst**
*Axial T2WI MR shows racemose (multilobulated, grape-like) NCC cysts extending into the suprasellar cistern
and the cerebellopontine angles
. Racemose NCC typically involves the basal cisterns and lacks a typical scolex.*

**Craniopharyngioma**
*Coronal T2WI MR shows a CSF-like intrasellar mass
. Surgery disclosed intrasellar craniopharyngioma with only a small suprasellar component. The vast majority of craniopharyngiomas are sellar and suprasellar. Only 5% of craniopharyngiomas are intrasellar.*

**Arachnoid Cyst**
*Sagittal T1WI MR shows an intra- and suprasellar arachnoid cyst
. The lesion did not restrict on DWI, differentiating it from epidermoid cyst.*

**Epidermoid Cyst**
*Axial T2WI MR shows a large epidermoid cyst extending into the sella and suprasellar subarachnoid space
from the quadrigeminal and ambient cisterns
.*