Case 261: Thymoma Embedded in Thymus with Pleural Implant in Myasthenia Gravis Lambert-Eaton Overlap Syndrome.

History A 29-year-old woman presented with a 6-month history of progressive general fatigue, fluctuating limb weakness, and difficulty climbing stairs. She initially experienced occasional episodes of transient diplopia that developed while reading in the evening. She subsequently started to experience dry eyes and mouth, difficulty chewing, and mild dysphagia that worsened throughout the day.

Case 261.

History A 29-year-old woman presented with a 6-month history of progressive general fatigue, fluctuating limb weakness, and difficulty climbing stairs. She initially experienced occasional episodes of transient diplopia that developed while reading in the evening. She subsequently started to experience dry eyes and mouth, difficulty chewing, and mild dysphagia that worsened throughout the day.

Nonsuppressing normal thymus on chemical-shift MR imaging and anterior mediastinal lymphoma: differentiation with diffusion-weighted MR imaging by using the apparent diffusion coefficient.

Objectives: To prospectively evaluate usefulness of the apparent diffusion coefficient (ADC) in differentiating anterior mediastinal lymphoma from nonsuppressing normal thymus on chemical-shift MR, and to look at the relationship between patient age and ADC.

Methods: Seventy-three young subjects (25 men, 48 women; age range, 9-29 years), who underwent chemical-shift MR and diffusion-weighted MR were divided into a normal thymus group (group A, 40 subjects), and a lymphoma group (group B, 33 patients). For group A, all subjects had normal thymus with no suppression on opposed-phase chemical-shift MR.

Dual-Energy X-ray Absorptiometry Predictors of Vertebral Deformities in Beta-Thalassemia Major.

Vertebral fractures in beta-thalassemia major are increasingly found because of the longer life expectancy of patients, with a major negative impact on their quality of life. We performed a retrospective cross-sectional study to investigate the prevalence of vertebral deformities in thalassemic patients and to identify their best dual-energy X-ray absorptiometry (DXA) predictor among trabecular bone score (TBS), bone mineral density (BMD), and Z-score. Eighty-two outpatients with beta-thalassemia major on regular conventional treatment were studied at a single academic center.

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

Purpose: To assess intra- and interobserver variability in the apparent diffusion coefficient (ADC) measurements of pleural abnormalities.

Materials And Methods: Diffusion-weighted magnetic resonance imaging was performed in 34 patients to characterize pleural abnormalities, with a 1.5T unit at b values of 0/150/500/800 sec/mm .

Radiological contribution to the diagnosis of early postoperative complications after lung resection for primary tumor: a revisional study.

In the post-operative course of the interventions of lung resection for primary tumor, complications of different nature and severity can arise, recognizing different pathogenetic mechanisms and differing according to the type of resection performed and to the time elapsed after surgery. The low diagnostic accuracy of chest radiography requires a thorough knowledge of the radiologist about all radiographic findings, both normal and pathological, which can be found in the immediate post-operative period (within 30 days after surgery). This article aims to describe the incidence, the clinical features and the radiological aspects of immediate complications following pulmonary resections, with specific reference to those in which the diagnostic imaging provides a fundamental contribution.

Apparent diffusion coefficient measurements in diffusion-weighted magnetic resonance imaging of the anterior mediastinum: inter-observer reproducibility of five different methods of region-of-interest positioning.

Objectives: To investigate inter-reader reproducibility of five different region-of-interest (ROI) protocols for apparent diffusion coefficient (ADC) measurements in the anterior mediastinum.

Methods: In eighty-one subjects, on ADC mapping, two readers measured the ADC using five methods of ROI positioning that encompassed the entire tissue (whole tissue volume [WTV], three slices observer-defined [TSOD], single-slice [SS]) or the more restricted areas (one small round ROI [OSR]), multiple small round ROI [MSR]). Inter-observer variability was assessed with interclass correlation coefficient (ICC), coefficient of variation (CoV), and Bland-Altman analysis.

Diffusion-weighted quantitative MRI to diagnose benign conditions from malignancies of the anterior mediastinum: Improvement of diagnostic accuracy by comparing perfusion-free to perfusion-sensitive measurements of the apparent diffusion coefficient.

Purpose: To compare perfusion-free to perfusion-sensitive measurements of the apparent diffusion coefficient (ADC) to diagnose benign conditions from malignancies of the anterior mediastinum.

Materials And Methods: Seventy-six subjects were divided into a "benign conditions" group (A, n = 44) and a "malignancies" group (B, n = 32), based on histological findings. diffusion-weighted magnetic resonance imaging (DW-MRI) was performed at b of 0/150/800 sec/mm(2) .

Chemical shift and diffusion-weighted magnetic resonance imaging of the anterior mediastinum in oncology: Current clinical applications in qualitative and quantitative assessment.

Recently, the use of magnetic resonance (MR) in clinical practice for the evaluation of the anterior mediastinum has considerably increased due to technological improvements and standardization of thoracic protocols. Currently, MR imaging is increasingly seen as a useful problem-solving modality, especially in equivocal cases at computed tomography, with the advantage of a higher contrast resolution and no radiation exposure. Chemical shift and diffusion-weighted MR are helpful in tissue characterization and present advantages over conventional MR imaging, first in providing quantitative data, without the need for the administration of contrast medium.

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.

Objectives: To evaluate the usefulness of diffusion-weighted magnetic resonance for distinguishing thymomas according to WHO and Masaoka-Koga classifications and in predicting disease-free survival (DFS) by using the apparent diffusion coefficient (ADC).

Methods: Forty-one patients were grouped based on WHO (low-risk vs. high-risk) and Masaoka-Koga (early vs.