Insidious Extension of Pituitary Prolactinoma: Two Can't-Miss Findings Depicted on a 3.0-T MR System

BACKGROUND In this article, we present two can't-miss findings on preoperative magnetic resonance imaging (MRI) using a 3.0-T MR system resulting in a better surgical option in prolactinoma treatment after emergent of dopamine agonists. METHODS We reviewed six cases of pituitary prolactinoma; each had vague or occult bulk of adenoma on 1.5-T MR imaging, which were finally confirmed by surgery. Four cases were preoperatively examined with a 3.0-T MR imaging system. With the 3.0-T MR system, 3-dimension-anisotropy-contrast (3DAC) MR imaging and 3-dimension fast spoiled gradient recalled acquisition in the steady state (3D-FSPGR) imaging were used for depiction of the adenoma. RESULTS 3DAC imaging revealed cavernous sinus (CS) pathology in three cases, and multiplanar reconstruction of 3D-FSPGR imaging revealed normal pituitary gland and invasive adenoma into the CS in three cases and creeping extension up to the contralateral side of the CS invasion in four cases. CONCLUSIONS Two can't-miss findings: (1) intrasellar creeping extension up to the opposite side of the adenoma main body and (2) intracavernous-localized adenoma with indistinct intrasellar mass should be carefully considered when neurosurgeons perform adenomectomy for patients with prolactinoma, even in cases of microprolactinoma.