Role of MRI Diffusion in Assessment of Mediastinal Lymphadenopathy, YOUSSRIAH Y. SABRI, MARIAN FAYEK, MOUSTAFA KHAIRY, MARWA MOAWAD and HEBA KHAFAGY
Abstract
Background: Diffusion MR imaging is a non-invasive functional imaging technique that can be incorporated into routine morphological MR examination to provide functional assessments of mediastinal lymphadenopathy. It can be used in differentiating benign from malignant lymph nodes as well as differentiating lymphoma from sarcoidosis.
Patients and Methods: This study included 23 patients; 15 males and 8 females in the period from June 2013 to July 2014. The mean age was 46.1±16.1 (range: 22-76 years). Cases were referred from the Chest and Oncology Departments to Radiology Department in Kasr El Aini Hospital for MRI assessment. The complaints varied between dyspnea, chest pain, cough, hemoptysis, fatigue and loss of weight. A super-conducting 1.5 T MRI machine with a four-channel body phased-array coil was used for the examination. Biopsy and histopathological assessment was done after that.
Results: MRI examination with diffusion weighted imaging was able to detect metastatic mediastinal lymph nodes that showed restricted diffusion with mean ADC value measuring (1.067±0.33) x 10-3 mm2/s. MRI diffusion weighted imaging can differentiate lymphoma from sarcoidosis in the setting of mediastinal/hilar lymphadenopathy. The mean ADC for lym-phoma was (1.22±0.23) x 10–3 mm2/s and for sarcoidosis was (1.9±0.28) x 10–3 mm2/s. The ADC value in the lymphoma group was lower than in the sarcoidosis group, and the differ-ence was statistically significant (p-value <0.001).
Conclusion: MRI with diffusion weighted images can detect malignant mediastinal lymph nodes, detect metastatic lymph nodes and differentiate lymphoma from sarcoidosis.