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Abstract: We studied five patients with mediastinal lymph node enlargement suggestive of malignant lymphoma, lung cancer, or sarcoidosis. Integrated [18F]fluorodeoxyglucose (FDG)-positron emission tomography (PET)/computed tomography (CT) was performed on all patients. Sarcoidosis can be a pitfall in PET/CT imaging, which may lead to false-positive results of malignancy. Increased FDG uptake in mediastinal lymph nodes is often comparable with malignant lymphoma or lymph node metastases. Histological confirmation of the lesions should be mandatory, except for patients in whom sarcoidosis can be accurately confirmed by other diagnostic methods. [Copyright &y& Elsevier]

Objectives: Exploring the modulatory effects of different frequencies of repetitive transcranial magnetic stimulation (rTMS) on the excitability of the motor cortex as measured by the input–output curve technique (I–O curve).Methods: Sixteen healthy subjects participated in this experiment. On two different sessions, conducted 1 week apart, rTMS was applied either at a frequency of 20 or 1 Hz at 90% of individual motor threshold (MT) for a total of 1600 pulses each. Before and after rTMS, the cortical excitability was assessed by measuring MT and the size of motor evoked potentials (MEPs) collected at different intensities of stimulation.Results: The analysis on the whole population showed a significant decrease of cortical excitability after 1 Hz rTMS and an increase after 20 Hz rTMS. A subsequent cluster analysis pointed out the presence of two distinct groups of subjects with opposite responses at the same frequency of stimulation. Significant variations on MT were found for both groups only for the facilitatory effect irrespective of the frequency of stimulation.Conclusions: The results provide further insight into interindividual differences in the effects of rTMS and suggest the existence of subpopulations with specific patterns of response to rTMS. [ABSTRACT FROM AUTHOR]