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M R I - Division

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Axial T1   Axial T2
 
Coronal T1   Coronal T2
 
Sgittal T1   Sagittal T2

 

 

Complaint : 40Y, Female c/o Headache from 3 months & visual disturbance from 1 week.

Investigation:

          MRI Brain T1 & T2 Wt. Images of Axial, Coronal & Sagittal sections.


FINDINGS:

MRI :  3.0 cm well defined smooth marginated iso intense lesion on T1 and slightly hyper intense lesion with

           fluid fluid levels which are hyper intense on T1    and mixed intense on T2 noted in the  sella and supra sellar

           regions. Lesion is figure of  eight in the coronal sections & displacing abutting the optic  chiasm Sell is widened.


DIAGNOSIS:  Pituitary macro adenoma with hemorrhage and abutting the optic chiasm

Differential Diagnosis :

    Pituitary hyperplasia

  • 25-50% of females 18-35 years have upwardly convex pituitary

    Usually <10 mm unless pregnant, lactating

    Homogenous enhancement

    Normal pituitary function

  • Can occur with end-organ failure (e.g. ovarian, thyroid)
  • If prepubescent female or young male has "adenoma-looking" pituitary, do endocrine workup.

   Aneurysm

  • Usually eccentric, not directly suprasellar
  • Pituitary gland visible, identified separate from mass
  • "Flow void" common on MR
  • Ca++ more common (rare in adenoma)

   Meningioma (diaphragma sellae)

  • Pituitary gland visible, can be identified separate from mass
  • Diaphragma sellae identifiable as thin, dark line between mass (above) and pituitary gland (below)
  • Dural thickening more extensive than with adenoma

   Metastasis

  • Diffuse skull  base invasion by adenoma may mimic more ominous disease
  • Occasionally can see systemic metastases to stalk, pituitary gland.

   Lymphocytic hypophysitis

  • Can mimic adenoma clinically, on imaging studies
  • Most common in peripartum female

   Craniopharyngioma

  • Ca++, cysts more common
  • Children > adults
  • Rim/nodular > solid enhancement

TIPS

  • Aggressive adenomas extend inferiorly, invade sphenoid, may destroy upper clivus
  • Giant adenoma => 4 cm in diameter. Prolactin levels are  often > 1000 ng/ml
  • No matter how aggressive/invasive adenoma looks, Pituitary tumors are almost never malignant

 

REFERENCE : Osborn,  Diagnostic Imaging, Brain 1st edition, 2004.

SUBMITTED BY:  Academic division, 'MA' Advanced Diagnostic & Research Centre, Guntur, AP. INDIA.

                              DR. M.ADINARAYANA RAO. MD.

                              DR. G.GOWRI SEKHAR . DNB.,DMRD.

                              DR. D. PRASAD REDDY. DMRD.

                              DR. Ch.SIVARAMA KRISHNA. DM(Neurology)

 


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