The study demonstrates that LeukoScan locates IBD. However, the sensitivity and specificity preclude its use for the routine detection of this disease. Comparisons with white cell scan images show that LeukoScan is taken up slowly in IBD and also appears in the normal bowel by 4 h.

A positive MIBI scan is highly predictive of the presence of significant residual disease on completion of chemotherapy. However, a negative MIBI scan does not rule out the presence of considerable residual tumour. Whereas ultrasound and clinical assessment may underestimate the response to chemotherapy, MIBI imaging tends to overestimate the response.

Accurate diagnosis is essential for the effective management of suspected bone infection. Current imaging techniques have had limited success and further work is required. Although white cell labelling techniques have been available for many years the radiopharmaceuticals employed have disadvantages, particularly in their availability and suitability for imaging. These problems have been overcome by the use of 99Tcm-HMPAO as an in vitro leukocyte labelling agent. The aims of this study were to assess retrospectively its role and accuracy in imaging orthopaedic infection and to compare the results with three-phase bone imaging. 30 patients with suspected bone infection underwent three-phase methylene diphosphonate (MDP) bone imaging and labelled leukocyte imaging on separate occasions. 16 bone scans were positive for infection, of which 14 were subsequently confirmed, and there were no false negatives. There were no false positive white cell studies and only one infection was not identified. 99Tcm-HMPAO white cell imaging has been shown to be an accurate technique for the diagnosis of bone infection but should be performed only following a positive finding on three-phase bone scanning, since the latter is highly sensitive but significantly less expensive, making it a more appropriate screening procedure.

In this pilot study GCPET has been shown to be feasible in a district general hospital, enabling a limited on-site PET imaging service to be provided. In the cases studied it was more sensitive than mammography or ultrasonography. GCPET may provide additional information that could be important in planning the management of some patients with breast cancer.

BRITISH MEDICAL JOURNAL 3 SEPTEMBER 1977 603 metoprolol, however, a dissociation between its lipolytic and cardiac actions was noted. These results indicate therefore differences in the metabolic effects of metoprolol, acebutolol, and propranolol but give no insight into the mechanisms concerned.Attempts to reduce blood lipid levels in patients with hyperlipaemia with beta-adrenoceptor antagonists have yielded inconsistent results."3'3 Carruthers and Taggart'5 have shown, however, that oxprenolol suppresses the rise in free fatty acid concentrations that occurs in response to stress. Prolonged treatment with beta-adrenoceptor antagonists might therefore serve to control lipid metabolism and minimise its atherogenic potential. To investigate this would require long-term studies and, as yet, none have been performed. The findings of this study therefore suggest that, should such a trial be undertaken, acebutolol and propranolol may show a greater therapeutic effect than metoprolol. Journal, 1977, 2, 603-605 Summary Bone scans using technetium-99m phosphate complexes and a rectilinear scanner were carried out on 192 women with primary operable breast cancer four to six weeks after operation. The lymph node status of all these patients was assessed histologically from triple node biopsy specimens. Only nine patients had positive scans, although 94 patients had histological evidence that the tumour had already spread beyond the confines of the breast.Bone scanning, although accurate as a prognostic guide, is helpful only in a very few cases, and serves mainly to confirm prognostic information obtained more simply and less expensively by histological examination of lymph node biopsy specimens.