Vertebral bone marrow infiltration of acute leukemia: diffusion-weighted imaging study / 中华放射学杂志

ABSTRACT

Objective Using single direction dispersion breathless DWI, to analyze the value of DWI for vertebral bone marrow infiltration in patients with acute leukemia (AL). MethodsForty-two patients with AL and 15 healthy volunteers received vertebral sagittal DWI with single shot spin-echo echoplan imaging (SS-SE-EPI) sequence( b value ＝ 0,650 s/mm2) at a GE Signa Excite 1. 5 T scanner with 8 channels body coil. DWI for all patients were performed from three directions, including from superior to inferior (S/I), from anterior to posterior (A/P) and from right to left (R/L). The apparent diffusion coefficient (ADC) value was measured on ADC map from each direction using GE-Function tool DWI software. Forty two patients consisted of 13 onset with untreated patients and 29 treated patients (7 nonremission,8 complete remission and 14 consolidation therapy). The ADC values among the three diffusion directions were compared. Analysis of variance and t test were used to compare the ADC values in different AL stages, Pearson correlation analysis was used to analyze the correlation between ADC values and the percentage of bone marrow progenitor cells. Results The ADC values from S/I, A/P and R/L of 362 vertebras in the 57 subjects are (0. 758 ±0. 009) × 10-3 mm2/s, (0. 732 ±0. 009) × 10 -3 mm2/s and (0. 758 ±0. 009) × 10 -3 mm2/s, respectively. There is no statistical significance( F ＝ 2. 958, P ＞ 0. 05 ).The ADC values from S/I of 94 vertebras in 15 healthy volunteers is (0. 697 ± 0. 122) × 10 -3 mm2/s, of 85 vertebras in 13 untreated AL patients is (0. 592 ±0. 071 ) × 10-3mm2/s. There is statistical significance between them ( t ＝ 2. 568, P ＜ 0. 05 ) ; The ADC value of 183 vertebras in 29 treated AL patients [ ( 0. 796 ±0. 225 ) × 10-3mm2/s]is higher than that in untreated patients with statistical significance (t ＝ -1. 332,P ＜0. 05). One hundred and forty vertebras in patients with complete remission and consolidation therapy were [ (0. 786 ±0. 184) × 10-3 mm2/s],and 43 vertebras in patients with non-remission(NR) [ (0. 804 ±0. 327 ) × 10 - 3 mm2/s], there was not statistical significance between them ( t ＝ - 0. 160, P ＞ 0. 05 ). The ADC values from S/I direction of untreated patients showed significant negative correlation with the proportion of the blast cell in the bone marrow ( median value 26. 4％. Min 7.9％, Max 48. 2％ ) ( r ＝- 0. 524, P ＜ 0. 05 ). ConclusionsDWI of vertebral bone marrow is isotropy. ADC value is a non-invasive and quantitative index for evaluating the pathogenetic condition of AL.