Whole brain magnetization transfer histogram analysis of pediatric acute lymphoblastic leukemia patients receiving intrathecal methotrexate therapy.
OBJECTIVE
The purpose of this prospective study was to evaluate the hypothesis that magnetization transfer ratio (MTR) histogram analysis of the whole brain could detect early and subtle brain changes nonapparent on conventional magnetic resonance imaging (MRI) in children with acute lymphoblastic leukemia (ALL) receiving methotrexate (MTX) therapy.


METHODS
Subjects in this prospective study comprised 10 children with ALL (mean age, 6 years; range, 0-16 years). In addition to conventional MRI, magnetization transfer images were obtained before and after intrathecal and intravenous MTX therapy. MTR values were calculated and plotted as a histogram, and peak height and location were calculated. Differences in peak height and location between pre- and post-MTX therapy scans were statistically analyzed. Conventional MRI was evaluated for abnormal signal area in white matter.


RESULTS
MTR peak height was significantly lower on post-MTX therapy scans than on pre-MTX therapy scans (p = 0.002). No significant differences in peak location were identified between pre- and post-chemotherapy imaging. No abnormal signals were noted in white matter on either pre- or post-MTX therapy conventional MRI.


CONCLUSIONS
This study demonstrates that MTR histogram analysis allows better detection of early and subtle brain changes in ALL patients who receive MTX therapy than conventional MRI.
Yamamoto
Akira
A
Department of Diagnostic Imaging and Nuclear Medicine, Graduate School of Medicine, Kyoto University, 54 Kawahara-cho, Shogoin, Sakyo-ku, Kyoto-shi Kyoto 606-8507, Japan. yakira@kuph.kyoto-u.ac.jp
Miki
Yukio
Y
Adachi
Souichi
S
Kanagaki
Mitsunori
M
Fushimi
Yasutaka
Y
Okada
Tsutomu
T
Kobayashi
Michihiro
M
Hiramatsu
Hidefumi
H
Umeda
Katsutsugu
K
Nakahata
Tatsutoshi
T
van Buchem
Mark A
MA
Togashi
Kaori
K
D000293:Adolescent; D000964:Antimetabolites, Antineoplastic / Q000009:adverse effects*; D001921:Brain / Q000187:drug effects* / Q000473:pathology; D001927:Brain Diseases / Q000139:chemically induced / Q000175:diagnosis*; D002648:Child; D002675:Child, Preschool; D005240:Feasibility Studies; D006801:Humans; D007223:Infant; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008727:Methotrexate / Q000009:adverse effects*; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000188:drug therapy* / Q000473:pathology; D011446:Prospective Studies
D000964:Antimetabolites, Antineoplastic; D008727:Methotrexate