Varied microcirculation of pituitary adenomas at rapid, dynamic, contrast-enhanced MR imaging.

Abstract

The technique reveals the microcirculatory dynamics associated with pituitary adenomas and suggests a dominant arterial blood supply for macroadenomas. It can supplement routine spin-echo imaging for determination of cavernous sinus invasion. Limitations related to section positioning, resolution, and signal-to-noise ratio exist.

In Vivo Manganese MR Imaging of Calcium Influx in Spontaneous Rat Pituitary Adenoma

“…In the use of these agents such as gadolinium, differences in the dynamic release of the contrast agent from the vasculature to the interstitial space was examined to differentiate normal pituitary gland from adenoma. [24][25][26][27] These studies found that factors such as surrounding microvasculature, arterial blood supply, size of adenoma, and tumor type (fibrous versus soft) affected the variability in clinical diagnoses. 26 Although we have yet to perform such rigorous investigation on this newly proposed imaging method, the fact that Mn 2ϩ enters into cells by a means that is directly related to the activity of a cell suggests the potential for improved clinical pituitary tumor assessment.…”

Usefulness of the dynamic gadolinium-enhanced magnetic resonance imaging with simultaneous acquisition of coronal and sagittal planes for detection of pituitary microadenomas

“…In the dynamic gadolinium-enhanced MR imaging of pituitary glands, contrast enhancement has been estimated to occur in the following order described in previouslypublished papers: posterior lobe, stalk, anterior lobe, because a normal posterior pituitary lobe receives direct arterial blood supply from the inferior hypophyseal arteries; the stalk is supplied from the superior hypophyseal arteries; and the anterior lobe is supplied from the superior hypophyseal arteries indirectly through the pituitary portal system [1][2][3][4][5].…”

“…Most (65.4%) microadenomas were reported to show peak enhancement later than the adjacent pituitary anterior lobe [6], therefore, the early phase of dynamic contrast-enhanced MR imaging makes the distinction of a normal pituitary structure from an adenoma easier [1,2,[5][6][7][8].…”

“…Dynamic contrast-enhanced MR images for pituitary adenomas have usually been performed in coronal planes rather than in sagittal ones [1,2,7,9]. Therefore, small lesions between slices, or the lesions located at the far anterior or the far posterior aspect of the pituitary glands, might be overlooked on MR images using only the coronal direction.…”

“…Because pituitary adenomas gradually or rapidly enhance compared with normal anterior pituitary glands, they are detected more clearly in the early phase after injection of contrast material on dynamic contrast-enhanced MR imaging [1][2][3][4][5][6]. However, in the case of microadenomas that are small or located in the far anterior or the far posterior portions of glands, the lesions might be overlooked on MR images using only coronal imaging [7].…”