title: T2 corrected quantification method of L-p-boronophenylalanine using proton magnetic resonance spectroscopy for boron neutron capture therapy.
abstract: In the present study, we aimed to evaluate a T2 corrected quantification method of l-p-boronophenylalanine (BPA) concentration using proton magnetic resonance spectroscopy (MRS). We used five phantoms containing BPA (1.5, 3.0, 5.0, 7.5, and 10 mmol/kg=15, 30, 50, 75, and 100 microg(10)B/g), N-acetyl-aspartic acid (NAA: 3.0 mmol/kg), creatine (Cr: 5.0 mmol/kg), and choline (Cho: 3.0 mmol/kg). The signal intensities of BPA and internal water were corrected by T2 relaxation time. The absolute concentrations of BPA were calculated by proton MRS using an internal water signal as a standard. The major BPA peaks were detected between 7.1 and 7.6 ppm. Mean T2 relaxation time was 314.3+/-10.8 ms in BPA, 885.1+/-39.7 ms in internal water. The calculated BPA concentrations were almost same as the actual concentration of BPA and the correlation coefficient was 0.99. Our BPA quantification method was very simple and non-invasive, also it had high accuracy. Therefore, our results indicate that proton MRS can be potentially useful technique for in vivo BPA quantification in boron neutron capture therapy (BNCT).
authors.affiliation: Department of Neurosurgery, Institute of Clinical Medicine, Graduated School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba, Ibaraki, Japan.
authors.forename: Yohei
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: Tomonori
authors.initials: T
authors.lastname: Isobe
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Yamamoto
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Shibata
authors.forename: Izumi
authors.initials: I
authors.lastname: Anno
authors.forename: Kei
authors.initials: K
authors.lastname: Nakai
authors.forename: Makoto
authors.initials: M
authors.lastname: Shirakawa
authors.forename: Akira
authors.initials: A
authors.lastname: Matsushita
authors.forename: Eisuke
authors.initials: E
authors.lastname: Sato
authors.forename: Akira
authors.initials: A
authors.lastname: Matsumura
mesh_terms: D001896:Boron Compounds / Q000032:analysis* / Q000627:therapeutic use*; D016754:Boron Neutron Capture Therapy / Q000379:methods* / Q000706:statistics & numerical data; D006801:Humans; D007554:Isotopes / Q000032:analysis / Q000627:therapeutic use; D009682:Magnetic Resonance Spectroscopy / Q000295:instrumentation / Q000379:methods* / Q000706:statistics & numerical data; D019047:Phantoms, Imaging; D010649:Phenylalanine / Q000031:analogs & derivatives* / Q000032:analysis / Q000627:therapeutic use; D011522:Protons; D011838:Radiation-Sensitizing Agents / Q000032:analysis* / Q000627:therapeutic use*
chemical_list: D001896:Boron Compounds; D007554:Isotopes; D011522:Protons; D011838:Radiation-Sensitizing Agents; D010649:Phenylalanine; C033685:4-boronophenylalanine