Diagnostic and functional imaging of thymic and mediastinal involvement in lymphoproliferative disorders

Diffusion‐weighted quantitative MRI of pleural abnormalities: Intra‐ and interobserver variability in the apparent diffusion coefficient measurements

“…However, none of the studies on DW‐MRI of pleural disease evaluated the measurement variability of the ADC between different readings or readers . Whenever quantitative data obtained from functional imaging are used for characterization or stratification of disease, it is mandatory to assess the intra‐ and interobserver variability of the manual or semiautomated method of measurement in order to determine the limits of error in obtaining quantitative data . This issue should be highly stressed when applied to the complex morphology and unique growth pattern of diffuse pleural disease (e.g., MPM, diffuse pleural implants in thymic epithelial tumors), which often grows as a rind around the pleural surface .…”

“…imaging are used for characterization or stratification of disease, it is mandatory to assess the intra-and interobserver variability of the manual or semiautomated method of measurement in order to determine the limits of error in obtaining quantitative data. 2,3,[35][36][37] This issue should be highly stressed when applied to the complex morphology and unique growth pattern of diffuse pleural disease (e.g., MPM, diffuse pleural implants in thymic epithelial tumors), which often grows as a rind around the pleural surface. 29,30 Our study demonstrates that, in pleural abnormalities, repeatability of ADC measurements is higher in protocols that include the entire tumor on one or more slices compared to methods that include portions of tumor selected on the basis of visual assessment on ADC maps.…”

Diffusion-weighted magnetic resonance imaging of thymoma: ability of the Apparent Diffusion Coefficient in predicting the World Health Organization (WHO) classification and the Masaoka-Koga staging system and its prognostic significance on disease-free survival

“…Blood flow may determine significant signal attenuation over the low b-value range (from 0 to 100 s/mm 2 ), which artificially inflates diffusion estimates and thus may be mistakenly attributed to diffusion. 13,[25][26][27][28] In contrast with Abdel Razek, that distinguished Masaoka-Koga stage I disease (non-invasive THY) from higher stages (II-IV, invasive THY), we assessed whether DW-MRI could distinguish stage I-II (non-advanced THY, no neo-adjuvant therapy before surgery required), from stage III-IV (advanced THY, neo-adjuvant treatments needed). 11 Although we found a significantly higher mean ADC in non-advanced THY compared to advanced THY, this finding may have been influenced by the higher percentage of type B3 THY in advanced THY subgroup (56% versus 7% of nonadvanced THY subgroup).…”

Chemical-Shift and Diffusion-Weighted Magnetic Resonance Imaging of Thymus in Myasthenia Gravis

“…Blood flow may determine significant signal attenuation over the low b value range (0-100 s/mm 2 ), which artificially inflates diffusion estimates and thus may be mistakenly attributed to diffusion. 13,[25][26][27][28] In contrast with the study of Abdel Razek et al 11 that distinguished Masaoka-Koga stage I disease (noninvasive THY) from higher stages (II-IV, invasive THY), we assessed whether DW-MRI could distinguish stages I and II (nonadvanced THY, no required neoadjuvant therapy before surgery) from stages III and IV (advanced THY, neoadjuvant treatments needed). Although we found a significantly higher mean ADC in nonadvanced THY compared with advanced THY, this finding may have been influenced by the higher percentage of type B3 THY in the advanced THY subgroup (56% vs 7% of the nonadvanced THY subgroup).…”