European journal of radiology
-
High grade gliomas (HGGs) are infiltrative in nature. Differentiation between vasogenic edema and non-contrast enhancing tumor is difficult as both appear hyperintense in T2-W/FLAIR images. Most studies involving differentiation between vasogenic edema and non-enhancing tumor consider radiologist-based tumor delineation as the ground truth. However, analysis by a radiologist can be subjective and there remain both inter- and intra-rater differences. The objective of the current study is to develop a methodology for differentiation between non-enhancing tumor and vasogenic edema in HGG patients based on T1 perfusion MRI parameters, using a ground truth which is independent of a radiologist's manual delineation of the tumor. ⋯ The current study proposes a semiautomatic method for segmentation between non-enhancing tumor and vasogenic edema in HGG patients, based on an SVM classifier trained on an alternative ground truth to a radiologist's manual delineation of a tumor. The proposed methodology may prove to be a useful tool for pre- and post-operative evaluation of glioma patients.
-
To evaluate MRI accuracy in assessing placental adhesion disorders (PAD) in patients with placenta previa correlating imaging results with histological findings. ⋯ MRI is a useful imaging technique to assess PAD in patients with placenta previa; in particular, the presence of at least two among all the abnormal MRI signs represents the most accurate criterion (Method B) to identify PAD. Although intraplacental dark bands and focal interruption of myometrial border showed the highest correlation with histological proof of PAD as well as this association was the most frequent in PAD, the combination of these latter MRI signs along with other abnormal signs should be considered diagnostic for PAD.
-
We previously reported the Screening with tomosynthesis or standard mammography-2 (STORM-2) trial, showing that tomosynthesis (3D-mammography) screening detected more cancers than 2D-mammography in double-reading practice. In this study, we report reader-specific detection measures for radiologists who performed the screen-reading in this trial. ⋯ There was variability in the magnitude of effect from integrating 3D-mammography (relative to screen-reading with acquired or synthesised 2D-mammography alone) on individual radiologist's TP and FP detection, although there was an overall pattern of increasing cancer detection and also increasing FP recall for most readers.
-
Accurate prediction of pathological N2 metastasis is crucial for choosing the best therapeutic strategy for non-small cell lung cancer (NSCLC) patients. The aim of this study is to evaluate the usefulness of metabolic heterogeneity assessed by the positron emission tomography combined with computed tomography (PET/CT) using F-18 fluorodeoxyglucose (FDG) in primary NSCLC with clinically suspected N2 metastasis in predicting pathological mediastinal lymph node metastasis. ⋯ Among the 50 patients with clinically suspected N2, 23 patients were pathologically confirmed as positive mediastinal lymph node metastasis and 27 patients were negative. Pathologically confirmed positive mediastinal lymph node metastasis group presented higher COV than the negative metastasis group (p < 0.001). An optimal cut-off value of 41.9 was proposed for discriminating metastasis from non-metastasis group. The sensitivity and specificity were 65.2% and 88.9%, respectively (AUC: 0.84; p < 0.0001). In addition, compared with other metabolic parameters, metabolic heterogeneity defined as COV showed the superior predictability of the mediastinal metastasis. (p = 0.001) CONCLUSION: Metabolic heterogeneity which was defined as COV of primary tumor could predict pathological mediastinal lymph node metastasis in NSCLC patients with clinically suspected N2. Therefore, COV of primary tumor may play a complementary role to conventional imaging in providing nodal information before taking biopsy.
-
To evaluate the value of intravoxel incoherent motion (IVIM) histogram analysis based on whole tumor volume in predicting microvascular invasion (MVI) of single hepatocellular carcinoma (HCC). ⋯ Histogram analysis of IVIM based on whole tumor volume can be useful for predicting MVI. The 5th percentile of D was most useful value to predict MVI of HCC.