Role of respiratory-triggered diffusion-weighted MRI in the assessment of pleural disease

The British Journal of Radiology 2016 June 15 [Epub ahead of print] [Link]

Revelli M, Chiesa F, Del Prato A, Tagliafico A, Rosenberg I, Canessa PA, Pinelli V, Villa A.


to evaluate the correlation between apparent diffusion coefficient (ADC) values and histopathological features in a cohort of patients with suspected malignant pleural disease.
we evaluated 56 consecutive patients undergoing a chest MRI examination for clinical suspicion of malignant pleural disease; all patients underwent thoracoscopic biopsy for histological assessment. All MRI exams were performed with a 1.5T scanner using a dedicated protocol, including a respiratory-triggered diffusion-weighted sequence with 3 b values (0, 100, 750). ADC values were calculated and a statistical analysis was performed.
Average ADC value in non-neoplastic pleural disease (NNPD) resulted of 1.84 ± 0.37 × 10-3 mm2/s, while we obtained an average value of 0.96 ± 0.19 × 10-3 mm2/s in epitheliod, of 0.76 ± 0.33 × 10-3 mm2/s in biphasic and of 0.67 ± 0.2 × 10-3 mm2/s in sarcomatoid pleural mesotheliomas. Histology revealed the presence of malignant pleural mesothelioma (MPM) in 44 patients, chronic pleuritis in 8 patients and atypical mesothelial hyperplasia in 4 patients. Statistical analysis showed a significant difference between NNPD and MPM (p < 0.001) and between epithelioid and sarcomatoid MPM subtypes (p = 0.0004), while biphasic MPMs showed a wide range of overlapping with the other groups. CONCLUSIONS: we observed a statistically significant difference between NNPD, epitheliod and sarcomatoid subtypes of MPM regarding ADC values. ADVANCES IN KNOWLEDGE: our study confirmed previous data regarding distribution of ADC values in pleural disease using a respiratory-triggered diffusion-weighted technique that allowed us to minimize motion artifacts and to reduct acquisition time.