Diagnostic Imaging Pathways - Pituitary Fossa Mass

Image Gallery

Pituitary Microadenoma

Image 1a (T1 weighted), 1b and 1c (T2 weighted) (Magnetic Resonance Imaging): There is a lesion seen within the pituitary gland centred to the right of the midline which is of high signal intensity on the T2 weighted imaging and shows slightly reduced signal intensity compared with adjacent pituitary on the T1 weighted imaging. Overall, the lesion measures up to 6mm. The lateral aspect of the lesion is abutting the medial aspect of the cavernous segment of the right internal carotid artery. The superior aspect of the pituitary is directly adjacent to the inferior aspect of the optic chiasm. The appearances are consistent with a pituitary microadenoma.

Pituitary Macroadenoma (Cushing's Disease)

Image 2a and 2b (Magnetic Resonance Imaging): There is a 13mm right sided pituitary adenoma (arrows) causing deviation of the stalk to the left. Slight suprasellar extension is noted without impingement of the chiasm or optic nerves.

Pituitary Macroadenoma

Image 3a and 3b: Post-mortem specimens showing a circumcribed nodular tumour arising from the anterior pituitary consistent with a macroadenoma.

Image 3c (H&E, x2.5) and 3d & 3e (H&E, x20): Histological sections demonstrating a circumscribed lesion composed of sheets of uniform polygonal cells with centrally placed nuclei and amphophilic cytoplasm. The features are consistent with a pituitary adenoma.