Evaluation of gravity effect on liver and spleen volumes using multiposture MRI.

Liver and spleen volume measurements are important for early detection and monitoring of liver disease. However, alterations in liver and spleen volumes with postural changes, i.e., the different effects of gravity, remain unclear. This study aims to evaluate the effects of posture on the liver and spleen in the supine and upright positions with an original magnetic resonance imaging (MRI) system capable of imaging in any posture (multiposture MRI). The liver and spleen volumes were assessed in ten healthy volunteers (age range: 20-24 years) in the supine and upright positions with multiposture MRI (0.4 T) and compared between postures. The liver and spleen volumes were significantly smaller in the upright position than in the supine position (P < 0.05 for both). Multiposture MRI offers more detailed information on liver and spleen volumes.