PMC

HN: normal pituitary; ACTH: ACTH-secreting pituitary tumor; GH: GH-secreting pituitary tumor; NS: non-secreting pituitary tumor.

Imaging manifestations of hyperintense signal in posterior pituitary in different sellar diseases. Figures (A–I) show an MRI sagittal T₁WI non-enhanced scan of different lesions in the sellar region. (A) A 30-year-old female, pituitary macroadenoma, ectopic hyperintense signal in the posterior pituitary, which is located at the posterior upper edge of the tumor (arrowhead). (B) A 64-year-old male, meningioma, normal hyperintense signal in the posterior pituitary, which is located behind the intrasellar adenohypophysis. (C) A 39-year-old male, craniopharyngioma, hyperintense signal in the posterior pituitary disappears. (D) A 54-year-old female, Rathke cleft cyst, hyperintense signal in the posterior pituitary disappears. (E) A 35-year-old female, germ cell tumor, hyperintense signal in the posterior pituitary disappears. (F) A 60-year-old male, metastatic tumor, hyperintense signal in the posterior pituitary disappears. (G) A 14-year-old female, glioma, hyperintense signal in the posterior pituitary disappears. (H) A 56-year-old female, cryptococcal granuloma of pituitary, hyperintense signal in the posterior pituitary disappears. (I) A 40-year-old female, abscess of the pituitary, hyperintense signal in the posterior pituitary disappears.

Magnetic resonance imaging (MRI) scan of the pituitary in our patients. Patient 1: The sagittal image showed that no pituitary was found in the pituitary fossa, the pituitary stalk was not seen, and the hyperintense signal disappeared in the posterior pituitary. Patient 2: The sagittal image showed that the anterior pituitary was slightly lower, the pituitary stalk could not be seen clearly, and posterior pituitary ectopia as well as bilateral lateral ventricle widening. Patient 3: The sagittal image showed that the anterior pituitary was slightly lower, the pituitary stalk was not seen, and the hyperintense signal disappeared in the posterior pituitary.

Photograph showing the inferior view of the pituitary gland (A). Dural fold of diaphragm is visible. The single layer representing the meningeal dural layer comes from the diaphragm and wraps around the pituitary gland. Photomicrograph showing the coronal section of the pituitary gland and stalk (B). Pituitary capsule which is composed of thin fibrotic capsule, encircles and tightly adhesive to the pituitary gland. It is continuous with the superior lateral margin of pituitary gland. The lateral surface of pituitary capsule is bordered by a thin dural layer, so called meningeal dural layer, which is continuous with the dural fold of diaphragma sellac superiorly and encircles undersurface of the pituitary gland inferiorly. DS : diaphragma sellae, MDL : meningeal dural layer, PC : pituitary capsule, PG : pituitary gland, PS : pituitary stalk.