Image J软件不同阈值处理模式在多裂肌脂肪浸润程度定量评估中的应用价值

Application value of Image J software in different threshold processing modes for the quantitative evaluation of fat infiltration of multifidus muscle

目的探讨Image J软件不同阈值处理模式在多裂肌脂肪浸润程度定量评估中的应用价值。方法选取40例中老年人作为研究对象,均进行MRI常规序列及磁共振波谱(MRS)序列扫描检查。由2名脊柱外科医生借助Image J软件的不同阈值处理模式测量L4~5椎间盘中心层面多裂肌脂肪浸润程度,1周后重复测量。采用组内相关系数(ICC)评估两名观察者之间及同一观察者不同时间的测量结果的可重复性。以MRS序列测量结果作为定量评估多裂肌脂肪浸润程度的“金标准”。分析Image J软件不同阈值处理模式所测得的多裂肌脂肪浸润程度与MRS序列所测结果的相关性。结果两名观察者之间及同一观察者不同时间测量的多裂肌脂肪浸润程度的可重复性均较高(均ICC>0.8)。Image J软件的固定阈值(60~140)模式、自动阈值模式、人工阈值模式测量的多裂肌脂肪浸润程度与MRS序列测量的多裂肌脂肪浸润程度均呈正相关(均P<0.05),其中采用固定阈值模式(阈值设置为80)时,Image J软件测量的多裂肌脂肪浸润程度与MRS序列测量的结果相关性最高。结论Image J软件不同阈值处理模式测量多裂肌脂肪浸润程度的可重复性高,采用固定阈值处理模式(阈值设置为80)在MRI常规序列上测量可替代MRS序列测量,作为评估多裂肌脂肪浸润程度的有效方法。

Objective To explore the application value of Image J software in different threshold processing modes for quantitative evaluation of fat infiltration of multifidus muscle.Methods A total of 40 middle-aged and elderly individuals were selected as the research subjects,and all of them completed MRI routine sequencing and magnetic resonance spectroscopy(MRS)sequencing scan examinations.Two spine surgeons measured fat infiltration of multifidus muscle at L4/5intervertebral disc central layer by virtue of Image J software in different threshold processing modes.The measurement was repeated after one week.The repeatability of measurement results between the two observers and between various time points of the same observer was evaluated by using inter class correlation coefficient(ICC).The measurement results of MRS sequencing was taken as the"gold standard"for the quantitative evaluation of fat infiltration of multifidus muscle.The correlation of fat infiltration of multifidus muscle measured by Image J software in different threshold processing modes with the results measured by MRS sequencing was analyzed.Results The repeatability of fat infiltration of multifidus muscle measured bettween the two observers and between various time points of the same observer were relatively high(all ICC>0.8).Fat infiltration of multifidus muscle measured by Image J software in fixed threshold(60~140)mode,automatic threshold mode,and artificial threshold mode positively correlated with fat infiltration of multifidus muscle measured by MRS sequencing(all P<0.05),therein,when the fixed threshold mode was adopted(threshold set at 80),fat infiltration of multifidus muscle measured by Image J software had the highest correlation with the results measured by MRS sequencing.Conclusion Image J software in different threshold processing modes exerts a high repeatability in quantitative evaluation of fat infiltration of multifidus muscle.Employing the fixed threshold processing mode(threshold set at 80)in the measurement of MRI routine sequencing can be replaced MRS sequencing measurement,and can be an effective method for evaluating fat infiltration of multifidus muscle.