A washout study in carbon ion therapy using a OpenPET prototype

2014 Fiscal Year Final Research Report

• Project/Area Number: 24700514
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Medical systems
• Research Institution: Gunma University (2014); National Institute of Radiological Sciences (2012-2013)
• Principal Investigator: HIRANO Yoshiyuki 群馬大学, 医学(系)研究科(研究院), 助教 (00423129)
• Project Period (FY): 2012-04-01 – 2015-03-31
• Keywords: In-beam PET / 重粒子線治療 / コンパートメントモデル / 洗い出し

Outline of Final Research Achievements

Positron emission tomography (PET) provide a promising tool for in situ noninvasive confirmation of the treatment delivery in ion beam therapy. We developed an in-beam PET dubbed OpenPET, , and successfully imaged C-11 distribution in a phantom irradiation. However, images of living objects are blurred due to washout by physiological effects. To compensate the washout effects, to obtained absolute washout rate and understanding the mechanism is important. The present study provided values of washout rates, k2m=0.54 min-1 and k2s=0.011 min-1 with a model (two washout model) for rat brain irradiations. The faster value was found to be close to cerebral blood flow. Also we compared washout rates with and without administration of acetazolamide which is vasodilator. Slower washout rates were observed for the stressed group. This may be explained by implanted C-11 turned into CO2 because acetazolamide is inhibitor carbonic anhydrase.

Free Research Field

医学物理