MRI findings and endocrinological dysfunction in hemorrhagic pituitary adenoma

: Magnetic resonance image (MRI) findings, intraoperative macroscopic findings and endocrinological functions were reported in 13 cases of hemorrhagic pituitary adenoma (HPA) according to clinical severity. The cases were divided into 3 groups: (1) classical pituitary apoplexy (PA) (n = 2), (2) subacute PA (n = 4), (3) asymptomatic HPA (n = 7). Based on MRI intensity and intraoperative findings, there were 7 cases with hemorrhagic PA and 5 with necrotic cyst formation. MRI intensities predicted the cyst contents, either hemorrhagic or xanthochromic, more accurately than CT findings. In addition, two classical cases of the PA group disclosed niveau formation on MRI, but MRI intensity in the first case differed from that in the second case. Classical PA of the first case occurred during the pregnancy. MRI intensity in the case 7 months after the onset disclosed high intensity of the upper part and normointensity of the lower part. T1 weighted image and proton image showed homogeneous intensity. On the contrast, PA of the second case showed water-like intensity on the upper part and methemoglobin-like intensity on the lower part. These different MRI intensities suggest different etiologies of niveau formation. MRI findings in the first case may indicate the chronic stage of massive intratumoral hemorrhage but the mechanism may be the same in both cases. From MRI intensity and clinical course, the cause of niveau formation in the second case is similar to that found in the literature. That is, hemorrhage was thought to have occurred in the pre-existing cyst cavity.(ABSTRACT TRUNCATED AT 250 WORDS)