The clinical utility of radionuclide emission tomography of the kidney in comparison with conventional gamma-camera imaging has been assessed from scans of 60 patients suspected of having space-occupying lesions of the kidney. Nineteen patients had renal tumour, 17 had cysts and seven had renal pseudotumours; the remainder had no lesion. Objective trials using four observers showed only a slight, statistically insignificant advantage from the addition of tomographic sections to conventional images. However, in several individual cases tomography had aided diagnosis, particularly in obese patients, when an alternative non-invasive investigation (ultrasonography) was inconclusive. In seven patients a positive diagnosis of renal pseudotumour was made possible by tomography; definite identification of ectopic functioning cortical tissue at the location of a mass suspected after urography was considered to be a distinct diagnostic advantage gained from emission tomography of the kidney.

No abstract

A new technique has been developed for presenting myocardial tomograms that allows the observer to perceive the shape of the thallium-201 distribution directly. The surface of the myocardium was found by applying an interactive thresholding technique to a set of conventional transverse slices. Computer graphics techniques were used to display a shaded image of that surface on a television screen, showing the three dimensional shape of the myocardial surface from any chosen aspect. A set of normal preserved coronary arteries was digitised, and using scaling and transformation techniques these arteries were mapped on to the myocardial tomograms and a shaded surface image produced with superimposed coronary arteries. This provided a familiar anatomical framework for locating perfusion defects. Its value in identifying various diseased vessels was confirmed by a comparison of the tomographic findings with the angiographic findings in five individual cases.

No abstract

A case of recurrent osteoblastoma of the hamate is reported. Curettage and bone grafting is usually followed by recurrence. Wide excision of the tumor is the treatment of choice if anatomically feasible.