The pineal volume: a three-dimensional volumetric study in healthy young adults using 3.0 T MR data.

It is usually difficult to distinguish small pineal tumors via routine or enhanced magnetic resonance (MR) scan. The knowledge of normal pineal size is helpful to detect small pineal lesions, while very few true volumetric data of pineal glands have been reported. Therefore, we obtained the accurate reference range of normal pineal volumes in 112 individuals aged 20-30 years recruited randomly from a healthy community sample. Transverse and sagittal 3.0T magnetic resonance data were obtained using three-dimensional (3D) T1-weighted FSPGR and T2-weighted SE sequences. True pineal volumes were measured from T1-weighted images, while estimated volumes were calculated using pineal length, width and height. All the glands were divided into three types according to the maximum inner diameter of pineal cysts. The prevalence of asymptomatic pineal cyst is 25.00%, with a slight female predominance. In the whole sample, we found no gender differences of pineal volume, but a significant gender difference of pineal volume index. A significant correlation between pineal volume and asymptomatic cyst was found. After excluding cases with big pineal cysts, there were significant correlations between pineal volume and head circumference, body height and body weight, respectively. This study suggests that asymptomatic pineal cysts may exert an important influence on pineal volume.