Cutaneous melanoma in a ferret (Mustela putorius furo).

A 4-year-old spayed female ferret (Mustela putorius furo) was clinically evaluated for a slightly raised subcutaneous mass in the dorsal lumbar area. The mass was surgically excised and submitted for histopathologic evaluation. Histologically, the mass was composed of closely packeted large, atypical, polygonal to spindle-shaped cells arranged in sheets and short bundles. A few cells contained variable amounts of granular, brown to black intracytoplasmic pigment. Warthin-Starry and Fontana-Masson silver stains demonstrated variable numbers of fine black intracytoplasmic granules in most cells. The atypical cells stained positively for vimentin and S100 protein and negatively for cytokeratin and Melan A. Ultrastructurally, the neoplastic cells contained intracytoplasmic melanosomes in different stages of development. Compound melanosomes were not identified. To our knowledge, this report documents the first case of a spontaneous cutaneous melanoma in the ferret.

Principles and appraisal of combined images in NMR.

The interpretation of NMR images at Aberdeen is most often performed by the individual study of the proton density, difference, inversion recovery and T1 image. This report investigates the usefulness of presenting the information from a pair of images, in this instance the T1 and proton density images, in a single composite image. Information from the two images is combined such that the values from one image are represented by a change in hue (colour), and the values from the other by a change in luminance (intensity). To test the advantages of such combined images, a trial was run using a selection of prediagnosed abnormal brain scans. The information perceived as hue and luminance in the combined images was compared with that from separate conventional monochrome proton density and T1 images. Medical and nonmedical users were told the final diagnosis and were asked whether it was possible to see more, less, or the same information with regard to clinically relevant details in the structure of the abnormality and the image as whole. The results have revealed that for the majority of cases the combined image format can effectively represent the information normally contained in both the monochrome proton density and T1 images--thus speeding up the image viewing process.