MRI texture analysis in differential diagnosis of orbital lymphoma and inflammatory pseudotumor / 中国医学影像技术

ABSTRACT

Objective To discuss the application value of texture analysis of conventional MRI in differential diagnosis of orbital lymphoma from inflammatory pseudotumor.Methods The conventional MRI data of 15 patients with lymphoma and 17 patients with inflammatory pseudotumor proven by pathology or clinical follow-up were retrospectively reviewed.The texture features of lesions based on axial T1WI,fat-saturated T2WI and contrast enhanced fat-saturated T1WI were extracted by manually drawn ROIs with software MaZda.The subsets of optimized texture parameters were chosen by four different methods:Fisher coefficient,probability of classification error and average correlation coefficient (POE+ ACC),mutual information measure (MI) and the combination of the above three methods (FPM),respectively.Linear discriminant analysis (LDA) and nonlinear discriminant analysis (NDA) were performed for texture classification.The texture features from the sequence with the best classification result of orbital lymphoma and inflammatory pseudotumor were compared.Results The optimal texture parameters were mainly derived from co occurrence matrix and run-length matrix on T1WI and T2WI.The optimal texture parameters were mainly derived from co-occurrence matrix and histogram on contrast enhanced T1WI.The best classification of MRI texture was obtained within T2WI with lowest classification error of 1.56％ achieved by FPM in combination with NDA.Comparing the texture parameters of orbital lymphoma and inflammatory pseudotumor on T2WI,the angular second moment and long length emphasis were significantly higher in orbital lymphoma (both P＜0.005),while the entropy and short length emphasis were significantly lower in orbital lymphoma (both P＜0.005).Conclusion It is feasible to use texture analysis on conventional MRI for the differentiation of orbital lymphoma and inflammatory pseudotumor.