MR imaging analysis of posterior pituitary in patients with pituitary adenoma

This study is to investigate posterior pituitary bright spot (PPBS) occurrence, distribution and its influencing factors by analyzing MRI-T1WI images in patients with pituitary adenoma (PA).

A total of 123 cases of PA patients were enrolled in this study. PPBS occurrence, distribution and MR signal characteristics were studied. The relationship of PPBS with PA morphology, tumor size, tumor height and immunohistochemical types were explored.

Among the 123 case of PA patients enrolled in the study, 98 cases were PPBS (+) and 25 cases were PPBS (-). According to tumor morphology, PA was divided into hourglass type (43 cases), barrel type (63 cases) and wedge type (17 cases). Occurrence rate of PPBS (+) in barrel type was less than those in hourglass and wedge types (P < 0.05). Tumor volume and height in PPBS (+) group were less than these in PPBS (-) group (P < 0.05). PPBS signal size in wedge and barrel types were larger than that of hourglass type (P < 0.05).

Sagittal MRI-T1WI images could well show posterior pituitary and PPBS (+) was related to tumor morphology, volume and height but had nothing to do with immunohistochemical types.