|Year : 2013 | Volume
| Issue : 7 | Page : 100-101
Pituitary gland imaging
Departments of Endocrinology, Diabetes and Metabolism, Christian Medical College, Vellore, India
|Date of Web Publication||11-Oct-2013|
Department of Endocrinology, Diabetes and Metabolism, Christian Medical College, Vellore - 632 004, Tamil Nadu
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Rajaratnam S. Pituitary gland imaging. Indian J Endocr Metab 2013;17, Suppl S1:100-1
| The Normal Pituitary Gland|| |
The pituitary gland lies within the sella. It measures approximately 13 mm in width, 10 mm in length, and 5 mm in height. The diaphragma sella covers the superior surface of the sella. On either side is the cavernous sinus containing the II, IV, V1, V2, and VI cranial nerves and the internal carotid artery.
On T1 weighted (T1W) imaging, the anterior pituitary appears isointense to gray matter and the posterior pituitary is seen as a bright spot due to the presence of neurosecretory granules containing antidiuretic hormone (ADH).
| Pituitary Psuedotumors|| |
Symmetrical enlargement of the pituitary gland which regresses with therapy is often associated with primary hypothyroidism.
Classification of pituitary adenomas
- Functioning adenomas/nonfunctioning adenomas
- Microadenomas/macroadenomas/giant adenomas
- Microadenomas < 10 mm in size
- Macroadenomas > 10 mm in size
- Giant adenomas > 4 cm in size 
The following point towards the location of a microadenoma 
- Convex superior surface on the side of the tumor
- Deviation of the pituitary stalk way from the lesion (70%)
- Relatively hypointense on T1
- Delayed enhancement on dynamic magnetic resonance imaging (MRI) [Table 1].
| Supra Sellar Tumors|| |
The epicenter of the mass lies in the suprasellar region. The mass has a cystic and a solid component. Proteinaceous content within the cyst can appear hyperintense on T1. CT scan confirms the presence of calcification.
The MRI scan shows a homogenously enhancing sellar mass with a large suprasellar component. They appear iso- to hypointense on the T2 weighted (T2W) image. T2 coronal images also reveal a dural tail.
Rathke's cleft cyst
Cystic mass with enhancing margins.
Cystic mass hypointense on T1 and hyperintense on T2.
Appears hypointense on T2 (flow void) and T1. The diagnosis is confirmed on magnetic resonance angiography (MRA).
Appears isointense to grey matter in T1W images and they do not show any enhancement with gadolinium.
A heterogeneously enhancing suprasellar mass involving the optic chiasm and normal appearing pituitary.
Well-circumscribed, intensely enhancing suprasellar/pineal lesion. Tumor spreading along the cerebrospinal fluid pathway.
Appears hyperintense on T1 due to their increased fat content. They cause focal erosion of bone.
| Parasellar Tumors|| |
Heterogeneous enhancement with honey comb appearance. Foci of hemorrhage within the tumor.
These include sarcoidosis, histiocytosis, hemochromatosis, tuberculosis, metastatic lesions and lymphomas.
Results from the herniation of the subarachnoid space into the sella. Primary empty sella results from a defect in the diaphragma sella. While secondary empty sella occurs following the destruction of the pituitary gland.
Hemorrhage into the gland appears hyperintense both on the T2W and T1W images. Infarction of the gland can be recognized as restricted diffusion.
The common MRI findings include:
- Absence of the normal hyperintensity of the posterior pituitary.
- Thickening of the pituitary stalk (normal stalk thickness 3.5 mm).
- Underlying hypothalamic/pituitary lesions.
- Associated bone and lung lesions.
| References|| |
|1.||Chacko G, Chacko AG, Lombardero M, Mani S, Seshadri MS, Kovacs K, et al. Clinico pathological correlates of giant pituitary adenomas. J Clin Neurosci 2009;16;660-5. |
|2.||Ouyang T, Rothfus WE, Ng JM, Challinor SM. Imaging of the pituitary. Radiol Clin North Am 2011;49:549-71. |
|3.||Mani SE, Irodi A, Sudhakar SV, Rajaratnam S. Radiology of the Pituitary. In: Bajaj S, editor. ESI Manual of Clinical Endocrinology. Hyderabad: Endocrine Society of India; 2012. p. 417-34. |