Peripheral nerve sheath tumors such as neurofibroma, comprise 5% of all benign soft tissue tumors and usually occur due to an underlying neurofibromatosis. A plexiform neurofibroma, which is a tumor occurring exclusively in neurofibromatosis1, is a rare entity and is an uncommon variant of neurofibroma. We report the clinical and imaging features of plexiform neurofibroma in two young male patients, in whom the imaging diagnosis was confirmed after biopsy. The report not only aims to highlight the characteristic imaging features of plexiform neurofibroma but we also emphasize the ultrasound appearances which are significantly characteristic and can effectively lead to the correct diagnosis at the preliminary stage of investigation. The tumors which originate from nerve sheath, are large, lobulated masses and demonstrate typical imaging features of simultaneous involvement of subcutaneous and cutaneous tissues along with infiltrative invasion of deeper structures. The tumors characteristically display fat and fluid contents and a “target sign’ on evaluation by ultrasound, CT and MRI. Imaging plays an important role in confirming the diagnosis, delineating involved structures, excluding simulating conditions and forewarning a possible malignant transformation.

Tuberculosis is an ancient disease known to have existed even in the Egyptian civilization. It is estimated that a quarter of the world's population is already infected and 1 million will die of the disease, in the current year. Although tuberculosis may occur in any organ, extra- pulmonary tuberculosis accounts for 10%-14% of all cases of tuberculosis. Skeletal involvement comprises only 1 to 5 % of all types of tuberculosis and the most frequently involved site in the skeleton is the vertebral column, amongst the skeletal structures, the sternum is involved very rarely, accounting for just 1-2% of all bone and joint tuberculosis. We report two cases of sternal tuberculosis,and enumerate the imaging appearances seen at ultrasound, CT and MRI and also highlight a relatively underemphasised complication of mediastinal involvement due to a retrosternal abscess. Rapid diagnosis by imaging studies led to early treatment and prevented catastrophic consequences of diffuse mediastinitis. Awareness of tuberculosis and its atypical skeletal manifestations is important not only in developing countries with endemic disease, but also in developed countries, due to its resurgence by the HIV epidemic and also because extensive international travel and transcontinental migration continues to facilitate greater disease transmission.