---
title: "Intrasellar Lesion"
docid: "391834ff-565f-401b-bfbd-0bc40f6b83bf"
authors:
- key: "e0282a62-994d-4550-a127-1eb773b1e920"
value: "Blair A. Winegar, MD"
- 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: "Intrasellar Lesion"
slug: "intrasellar-lesion"
treeNodeId: null
category: "Brain"
documentVersionId: "216cd491-5de9-461c-8fdd-c0c0580f06de"
imageCount: 21
lastUpdated: "03/15/23"
pageDescription: "Intrasellar Lesion"
pageKeywords: "Brain, Differential Diagnosis, Sella/Juxtasellar, Pineal Region, Anatomically Based Differentials, Intrasellar Lesion"
pageTitle: "Intrasellar Lesion | STATdx"
enhancedTitle: "Intrasellar Lesion"
type: "DDX"
references: true
breadcrumbs:
- "Brain"
- "Differential Diagnosis"
- "Sella/Juxtasellar, Pineal Region"
- "Anatomically Based Differentials"
- "Intrasellar Lesion"
---
# ESSENTIAL INFORMATION
- ## Key Differential Diagnosis Issues
- Not all "enlarged" pituitary glands are abnormal
- Size/height varies with sex, age
- Pituitary incidentaloma (cyst, nonfunctioning adenoma) in 15-20% of normal MRs
- If it does not enhance, cyst is more likely etiology than microadenoma
- ## Helpful Clues for Common Diagnoses
- **Pituitary Hyperplasia**
- Physiologic (e.g., young menstruating or postpartum female patients)
- Pathologic (end-organ failure, neuroendocrine tumors)
- Hypothyroidism is most common etiology
- **Pituitary Microadenoma**
- < 10 mm in diameter, may enlarge gland
- 70-90% hypointense, enhance more slowly than normal pituitary
- **Empty Sella**
- Intrasellar CSF collection → pituitary gland flattened against sellar floor
- 5-10% prevalence on MR
- May be associated with idiopathic intracranial hypertension
- ## Helpful Clues for Less Common Diagnoses
- **Rathke Cleft Cyst**
- T1WI: 50% hypointense, 50% hyperintense
- T2WI: 70% hyperintense, 30% isointense/hypointense
- Look for intracystic nodule (40-75%)
- **Craniopharyngioma**
- Completely intrasellar craniopharyngioma uncommon
- 90% rule: 90% calcify, 90% cystic, 90% enhance
- **Neurosarcoid**
- Affects hypothalamic-pituitary axis in ~ 50%
- Enhancement along infundibulum ± pituitary gland
- ## Helpful Clues for Rare Diagnoses
- **Lymphocytic Hypophysitis**
- Autoimmune inflammatory disorder, often pregnant or postpartum females
- Enhancing pituitary gland ± stalk
- May mimic macroadenoma
- **Intracranial Hypotension**
- Pituitary enlarged above sella in 50%
- Diffuse dural enhancement, slumping brainstem, cerebellar tonsillar ectopia, venous congestion
- **Saccular Aneurysm**
- Flow void or pulsation artifact may be seen ± lamellated clot
- **Lymphoma, Primary CNS**
- Often infiltrate adjacent structures
- ↓ T2 signal, ↓ ADC value
- **CNS Siderosis**
- "Black" pituitary gland on T2*
- Found with iron overload states > > subarachnoid hemorrhage (thalassemia, hemochromatosis)
## References
# Selected References
1. [Lubomirsky B et al: Sellar, suprasellar, and parasellar masses: imaging features and neurosurgical approaches. Neuroradiol J. 35(3):269-83, 2022](http://www.ncbi.nlm.nih.gov/pubmed/?term=34856828%5Bpmid%5D)
1. [Pascual JM et al: Duct-like recess in the infundibular portion of third ventricle craniopharyngiomas: an MRI sign identifying the papillary type. AJNR Am J Neuroradiol. 43(9):1333-40, 2022](http://www.ncbi.nlm.nih.gov/pubmed/?term=35953277%5Bpmid%5D)
1. [Yan S et al: Sellar region lesions and intracranial aneurysms in the era of endoscopic endonasal approach. Front Endocrinol (Lausanne). 12:802426, 2021](http://www.ncbi.nlm.nih.gov/pubmed/?term=35058885%5Bpmid%5D)
1. [Bond KM et al: Spontaneous intracranial hypotension: atypical radiologic appearances, imaging mimickers, and clinical look-alikes. AJNR Am J Neuroradiol. 41(8):1339-47, 2020](http://www.ncbi.nlm.nih.gov/pubmed/?term=32646948%5Bpmid%5D)
1. [Sahm F et al: WHO 2016 classification: changes and advancements in the diagnosis of miscellaneous primary CNS tumours. Neuropathol Appl Neurobiol. 44(2):163-71, 2018](http://www.ncbi.nlm.nih.gov/pubmed/?term=28295484%5Bpmid%5D)
1. [Go JL et al: Imaging of the sella and parasellar region. Radiol Clin North Am. 55(1):83-101, 2017](http://www.ncbi.nlm.nih.gov/pubmed/?term=27890190%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. [Kocova M et al: Diagnostic approach in children with unusual symptoms of acquired hypothyroidism. When to look for pituitary hyperplasia? J Pediatr Endocrinol Metab. 29(3):297-303, 2016](http://www.ncbi.nlm.nih.gov/pubmed/?term=26587741%5Bpmid%5D)
## Images
### Selected Images
without focal mass in this 18-year-old woman with hypothyroidism. Pituitary hyperplasia may be physiologic in menstruating, pregnant, or postpartum patients or pathologic, related to end-organ failure.](images/app.statdx.com_image_thumbnail_8c00b705-f73c-45f2-9bf2-ba5d6ee6318c_annotated_true_size_900_quality_90_e860c8be.jpg)
**Pituitary Hyperplasia**
*Coronal T1 C+ MR shows marked enlargement of the pituitary gland without focal mass in this 18-year-old woman with hypothyroidism. Pituitary hyperplasia may be physiologic in menstruating, pregnant, or postpartum patients or pathologic, related to end-organ failure.*
**Pituitary Hyperplasia**
*Coronal T1 C+ MR shows marked enlargement of the pituitary gland without focal mass in this 18-year-old woman with hypothyroidism. Pituitary hyperplasia may be physiologic in menstruating, pregnant, or postpartum patients or pathologic, related to end-organ failure.*
**Pituitary Microadenoma**
*Coronal T1 C+ MR shows a hypoenhancing nodule in the pituitary gland related to a growth hormone secreting microadenoma in this patient with acromegaly. Prolactinomas are the most common secreting pituitary adenoma.*
**Empty Sella**
*Sagittal T1 MR shows an expanded and empty sella in this patient with idiopathic intracranial hypertension. There is flattening of the pituitary gland along the sella floor.*
. Macroadenomas are > 10 mm and most commonly extend through the diaphragma sella into the suprasellar cistern. Displacement of the infundibulum is common.](images/app.statdx.com_image_thumbnail_96d514d5-434a-439a-90f8-9e8f48a0fe6e_annotated_true_size_900_quality_90_8e0fea9e.jpg)
**Pituitary Microadenoma**
*Coronal T1 C+ MR in a 43-year-old woman with elevated prolactin shows a hemorrhagic intrasellar macroadenoma . Macroadenomas are > 10 mm and most commonly extend through the diaphragma sella into the suprasellar cistern. Displacement of the infundibulum is common.*
within the pituitary gland between the adenohypophysis anteriorly and the neurohypophysis posteriorly related to a proteinaceous Rathke cleft cyst. An intracystic nodule may be seen in these benign cystic lesions.](images/app.statdx.com_image_thumbnail_6b03d972-0451-457c-bb06-645d3e01cc5d_annotated_true_size_900_quality_90_7b548833.jpg)
**Rathke Cleft Cyst**
*Sagittal T1 MR shows an intrinsic hyperintense lesion within the pituitary gland between the adenohypophysis anteriorly and the neurohypophysis posteriorly related to a proteinaceous Rathke cleft cyst. An intracystic nodule may be seen in these benign cystic lesions.*
is draped over the mass. Sarcoid was diagnosed at resection. Imaging mimics a macroadenoma.](a643be29-7404-46e0-bb98-16b3bd0eb3a6)
**Neurosarcoid**
*Coronal T1 C+ FS MR shows a sellar and suprasellar mass in this 32-year-old with mild prolactin elevation. Note the optic chiasm is draped over the mass. Sarcoid was diagnosed at resection. Imaging mimics a macroadenoma.*
, consistent with intracranial hypotension.](21e90ad0-8d2d-4dc9-869f-f1fbce133572)
**Intracranial Hypotension**
*Sagittal T2 FS MR shows a prominent pituitary gland , brainstem slumping , and cerebellar ectopia , consistent with intracranial hypotension.*
**Lymphoma, Primary CNS**
*Coronal T1 C+ MR shows a mass lesion diffusely infiltrating and expanding the pituitary gland . Note extension into the left cavernous sinus , suggesting more aggressive pathology. B-cell lymphoma was diagnosed at biopsy. Lymphoma typically has associated diffusion restriction which can help with an accurate preoperative diagnosis.*
### Additional Images
in this 28-year-old woman with seizures. Note the thinned pituitary gland along the sellar floor. The empty sella was incidental in this case but may be associated with idiopathic intracranial hypertension.](images/app.statdx.com_image_thumbnail_3c262b17-8739-4b67-a474-874cfb0607a6_annotated_true_size_900_quality_90_4b713379.jpg)
**Empty Sella**
*Sagittal T1 MR shows a partially empty sella in this 28-year-old woman with seizures. Note the thinned pituitary gland along the sellar floor. The empty sella was incidental in this case but may be associated with idiopathic intracranial hypertension.*
**Rathke Cleft Cyst**
*Coronal T2 MR shows an intrasellar Rathke cleft cyst with a small intracystic nodule . Visualization of an intracystic nodule helps to make an accurate preoperative diagnosis of Rathke cleft cyst. Imaging may mimic a cystic adenoma or a craniopharyngioma, though craniopharyngiomas typically have calcification.*
**Pituitary Hyperplasia**
*Coronal T1 C+ MR shows an enlarged pituitary gland in this asymptomatic 28-year-woman. Follow-up scan 1 year later was normal.*
. The lesion was hypointense on T2 MR. Rathke cleft cyst with inspissated contents was found at surgery.](1f614654-db0e-406a-a315-52bdb5646700)
**Rathke Cleft Cyst**
*Sagittal T1 MR shows a very hyperintense intrasellar mass . The lesion was hypointense on T2 MR. Rathke cleft cyst with inspissated contents was found at surgery.*
**Rathke Cleft Cyst**
*Coronal T2 MR shows a hyperintense cystic intrasellar mass found incidentally on MR. This is probably a Rathke cleft cyst or pars intermedia cyst.*
**Craniopharyngioma**
*Sagittal T1 MR shows a hyperintense intra-/suprasellar mass that displaces the pituitary gland . Totally intrasellar craniopharyngioma without suprasellar extension is rare.*
**Neurosarcoid**
*Coronal T1 C+ MR shows a slightly enlarged pituitary gland with a thickened infundibulum above in a patient with proven neurosarcoidosis.*
**Intracranial Hypotension**
*Sagittal T1 MR shows the classic "slumping midbrain" with draping of the optic chiasm over an enlarged pituitary gland .*
**"Kissing" Carotid Arteries**
*Coronal T2 FS MR shows "kissing" (paramedian) cavernous internal carotid arteries projecting medially into the sella turcica. Cavernous internal carotid arteries normally lie laterally within carotid sulcus of sphenoid bone.*
**Metastasis to Gland/Stalk**
*Sagittal T1 C+ MR shows a slightly enlarged, inhomogeneously enhancing pituitary gland and thickened infundibular stalk .*
**Pituitary Microadenoma**
*Coronal T2 MR shows a hyperintense intrasellar mass . Preoperative diagnosis was Rathke cleft cyst. An almost entirely cystic microadenoma was found at surgery.*
**"Kissing" Carotid Arteries**
*Coronal CT angiogram shows medialized course of the bilateral cavernous internal carotid arteries compressing the pituitary gland , compatible with "kissing" carotid arteries.*
**CNS Siderosis**
*Coronal T2* MR in a 9-year-old with long-standing thalassemia major shows a profoundly hypointense pituitary gland caused by iron overload syndrome. A hemorrhagic adenoma could have a similar appearance.*