ABSTRACT
PURPOSE: The purpose of this study was to investigate the possibilities for serial in vivo localized proton magnetic resonance spectroscopy (MRS) examination of bone marrow in patients with acute le,ukemia. MATERIALS AND METHODS: Selective measurements of the relaxation times Tl and T2 for the water and fat resonance in the bone marrow spectra were performed (1.5 Tesla whole body magnetic resonance scanner). Six patients with acute leukemia were examined at diagnosis. Follow-up examinations of four patients with acute leukemia in complete remission were also examined. Six normal control subjects were examined with identical methods for comparison. RESULTS: Significant differences could be detected in the spectral patterns from lumbar spine in patients with leukemia at diagnosis compared to healthy normal controls. The relative water content was increased in leukemic patients compared to normal subjects, which indicate an increase in the amount of hemopoietic tissue and a corresponding decrease in marrow fat content. A significant correlation was found between cellularity assessments derived from conventional bone marrow core biopsies and relative water content of proton MRS data. The Tl relaxation time of the water resonance in leukemic patients were significantly prolonged at diagnosis compared to normal controls. After chemotherapeutic induction of remission, the spectra from the bone marrow of lumbar spine resembled normal subjects. CONCLUSIONS: This method provide the possibility for serial measurements of bone marrow in patients with leukemia, and may provide information from regions inaccessible to bone marrow biopsy. This therefore appears to be a promising application of proton MRS that can be performed on a routine basis in a clinical setting.