PURPOSE: To evaluate the changes in splenic volume during hypovolemic shock and after recovery by use of multidetector computed tomography (MDCT). MATERIALS AND METHODS: We investigated 22 cases who underwent MDCT during hypovolemic shock up to 3 h after presentation, compared the splenic volume with that after recovery, and evaluated the volume difference. We compared the volume ratio (recovery/shock) for two age groups: under 60 years (n = 10) and 60 years and over (n = 12). For cases (n = 10) undergoing CT examination twice after treatment, we compared the volume ratios by using the initial recovery CT and the second CT images. RESULTS: The average spleen volume in shock was 63 cm(3); under normal conditions it was 132 cm(3) (P < 0.001). The average volume ratio for groups under 60 years old was 2.34; for groups 60 years and over it was 2.05 (P = 0.051). The average volume ratio obtained by use of the initial post-recovery CT was 2.11; the ratio obtained by use of the second post-recovery CT was 2.16 (P = 0.386). CONCLUSIONS: Our results revealed that splenic volume was reduced during hypovolemic shock and rapidly increased after recovery. Splenic contraction is an important CT finding in shock.