Diagnostic Value of Conventional MRI and DWI for Atypical Primary Central Nervous System Lymphoma(PCNSL)

Objective: To apply conventional Magnetic Resonance Imaging (MRI) and Diffusion-Weighted Imaging (DWI) to patients with atypical Primary Central Nervous System Lymphoma (PCNSL), and analyze its diagnostic value. Method: We selected 18 patients with atypical PCNSL who had been treated in our hospital from January 2018 to December 2019. All patients underwent conventional MRI and DWI, and we analyzed their MRI and DWI performance. Results: There were 24 lesions among the 18 patients in this group. MRI showed that the lesions were mostly in low signal on T1WI (83.33%), high signal on T2WI (83.33%), some with clear boundaries (62.5%), and some involved the midline structure or ventricles (62.5%). The single lesions were mostly nodular or mass-like enhancements (41.67%), and the multiple lesions were mostly ring-shaped enhancements (29.17%). DWI showed tumor epithelial high signal (54.17%) or slightly high signal (33.33%). The ADC value and rADC of tumor epithelial area, proximal and distal edema area around the tumor were significantly different (P<0.05). Conclusion: Conventional MRI and DWI showed obvious imaging characteristics of atypical PCNSL, with high diagnostic value.