Neurohypophysis in Bulgarian females – 3T MR morphometry in relation to physiology
I-V. Malla Houech, D. Zlatareva, V. Hadjidekov
The pituitary gland is one of the smallest endocrinе glands and it is a well-known fact that its dimensions vary in both sexes. Magnetic resonance imaging (MR) allows the differentiation of the hypophyseal structures. The characteristic T1 hyperintensity of the neurohypophysis is recognized on the T1 sequences. Its visualization is of great importance in distinguishing physiological from pathological conditions. An interesting matter of discussion are the correlation between the dimensions of the posterior lobe with the physiological conditions in females. The purpose is to obtain mean sizes of the neurohypophysis in the given population and to find a correlation between the dimensions and the physiological process. We retrospectively reviewed 168 MR examinations of the pituitary gland performed in women. The patients were referred to the imaging department due to different endocrinological pathologies. We excluded from the study the females with diagnosed central diabetes insipidus. The examination was obtained using a standard pituitary gland MR protocol, sequences performed in 2 mm thickness of the slice. We assessed the pituitary bright spot on the T1 sagittal images, this being able to measure the dimensions of the posterior lobe. The largest dimensions of the length and height were 6,25 mm and 7,87 mm respectively, whilst the lowest were 0,94 mm and 0.83 mm respectively. No significant correlation was found between the dimensions of the posterior lobe and the age, stature and weight. No such correlation was found neither with the reproductive state in females and the number of pregnancies. MR is the gold standard when imaging the pituitary gland. The hyperintensity of the neurohypophysis on the T1 sequences is an indicator of the function of the posterior lobe and allows assessing its proper morphometry.
Keywords: MR. NEUROHYPOPHYSIS. DIMENSION