Optimal strategy for measuring intraventricular temperature using acceleration motion compensation diffusion-weighted imaging.

DWI thermometry is affected by CSF pulsation. To achieve more accurate determination of intraventricular temperature, we compared conventional DWI (c-DWI), acceleration motion compensation DWI (aMC-DWI), and motion compensation DWI (MC-DWI) when using two different b values (commonly used b value [1000 s/mm2] and theoretically optimized b value according to the diffusion coefficient of the CSF [400 s/mm2]). Eight healthy volunteers were scanned using a 3.0-T magnetic resonance (MR) system. The temperature map was created using the diffusion coefficient from DWI with b = 1000 and 400 s/mm2, respectively. The intraventricular temperatures in the lateral ventricles (LV) with less CSF pulsation, and the third ventricle (TV), which has more CSF pulsation, were compared between three techniques using the Friedman test. We measured the body temperature in the axilla to compare it with the intraventricular temperature. With b = 1000 s/mm2, the intraventricular temperatures in TV for c-DWI were significantly higher (43.12 ± 2.86 °C) than those for the aMC-DWI (37.68 ± 1.66 °C; P < 0.05), whereas those in LV were not significantly different (P = 0.093). With b = 400 s/mm2, the intraventricular temperatures in TV for c-DWI (75.07 ± 5.48 °C) were significantly higher than those for the aMC-DWI (38.63 ± 0.92 °C; P < 0.05), whereas those in LV were not significantly different (P = 0.093). aMC-DWI provided an intraventricular temperature that was close to or slightly higher than the body temperature in either condition. However, c-DWI- and MC-DWI-measured temperatures were higher than the body temperature, particularly in the TV. Thus, aMC-DWI can accurately determine the intraventricular temperature.