Penoscrotal lymphedema associated with metastatic renal cell carcinoma.

A 64-year-old male presented with lower back pain, radiating in a sciatic-type distribution, swelling in his lower abdomen and right leg, and edema of the scrotum and penile shaft. A sonogram and CT imaging indicated an enhancing mass in the right kidney and a spinal metastasis. The right lower extremity and penoscrotal lymphedema was caused by lymphatic obstruction due to a sacral metastasis of renal cell carcinoma. He was treated with cytoreductive nephrectomy, radiation and a systemic tyrosine kinase inhibitor. Pelvic imaging is suggested to determine whether malignant lymphatic obstruction is present when presented with idiopathic penoscrotal edema.

Terahertz pulse imaging: a pilot study of potential applications in dentistry.

The improvement in the detection of caries offers the possibility for dramatic improvement in dental healthcare. Current caries detection rates suggest that there may be scope for improvement. This paper describes a preliminary study to examine applications of terahertz pulse imaging (TPI) to caries detection. We present results for the detection of early stage caries in the occlusal enamel layer of a range of human tooth cross sections using TPI. Higher attenuation of terahertz radiation was observed in carious enamel as compared with healthy enamel. Hypomineralised enamel had different absorption spectra and contrast compared to carious enamel in TPI images. These results have important implications for extending TPI to other medical imaging applications where both early diagnosis and safety issues are important.

Three-dimensional terahertz pulse imaging of dental tissue.

There are unresolved clinical problems that require the provision of accurate 3-D images of tissue structures such as teeth. In particular, measurements of dental enamel thickness are necessary to quantify problems associated with enamel erosion, yet currently there is no nondestructive method to obtain this information. We present a method that relies on the use of pulsed terahertz radiation to gain 3-D information from dental tissues. We discuss results from 14 samples and demonstrate that we can reliably and accurately quantify enamel thickness. We show that in a series of 22 surfaces, we can image pertinent subsurface features 91% of the time. Example images are shown where structures in teeth at depth are rendered accurate to within 10 microm. We discuss issues that arise using this imaging method and propose ways in which it could be used in clinical practice.