Objective: To explore the practicability and optimal dosage of polyaspartic acid (PASP)-surface-modified ultra-small superparamagnetic iron oxide (USPIO) (PASP-USPIO) in normal rabbit brain perfusion. Methods: Thirty New Zealand rabbits were randomly divided into groups A1, A2, A3, A4 and C. Animals in groups A1-4 were intravenously injected (i.v.) with 5 μmol/kg, 10 μmol/kg, 20 μmol/kg and 40 μmol/kg PASP-USPIO, while animals in group C were injected (i.v.) with 0.2 mmol/kg gadolinium diethyl triamine-pentoacetic acid (Gd-DTPA), serving as a control group. Each group was subjected to T 2* Gradient Echo-Echo Planar Imaging (T2*GRE- EPI)-sequenced perfusion-weighted imaging to obtain signal intensity-time curves, which were used to calculate the regional cerebral blood volume (rCBV), the maximum signal drop percentage (SRRmax), and Q rCBV-QSRRmaX values. Data were compared within and between groups. Results: The intra-group rCBV value and SRRmax value were significantly different between gray matter and white matter. The inter-group QrCBV and QSRRmax values were also significantly different. ANOVA analysis indicated that the QrCBV and Q SRRmax values in group A4 were significantly different from those in other groups, while there were no significant differences among group A1, A2, A3 and C. Conclusion: PASP-USPIO has colloid stability and can be used in normal rabbit MR brain perfusion. The optimal dosage is 10 μmol/kg. ? 2011 IEEE.
(8.0+极速模式)