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Focal increase in concentration of bone-seeking isotopes occurs in many pathological conditions including healing fractures, infection and metastatic deposits. Osteotomy frequently provokes comparatively little scintigraphically evident reaction, and the scintigraphic appearance commonly reverts to normal within a few months. Following fracture, on the other hand, increased uptake persists for a time which depends on the site, severity of trauma and possibly other undefined factors. Uptake may revert to normal within as little as eight weeks with effective immobilisation of a simple undisplaced fracture. At the other extreme increased uptake has been observed over thirty years after injury (Matin, 1979).

The discovery of a number of phosphate complexes labelled with 99Tcmthat localize in bone has aroused wide-spread interest in bone scanning. The physiological properties of these and other clinically useful bone-seeking radiopharmaceuticals are compared, and their physical properties assessed in relation to the characteristics and limitations of available detector systems. A hypothesis is put forward to explain the behaviour of the technetium-labelled agents.It is concluded that although there are differences in biochemical behaviour between these agents, strontium and fluorine, all three may, under suitable conditions, give similar clinical information. The radiation dose received by the patient is least with the usual dose of 99Tcm, and the blood clearance of the diphosphonate and pyrophosphate preparations is faster than that of strontium, although slower than fluorine. The ?-ray energy of technetium permits a much greater efficiency of detection than that of fluorine.These factors, together with the general availability of 99Tcmand its relatively low cost make the technetium diphosphonate or pyrophosphate preparations the agents of choice for most skeletal radioisotope imaging. However, there are as yet insufficient follow-up studies to be able to assess the incidence of either false-negative or false-positive findings with these agents.

The potential value of indium-labelled bleomycin as a diagnostic scanning agent has been investigated in patients with a variety of malignant neoplasms involving the thorax, abdomen or pelvis. Sixty-five patients were scanned on 72 occasions, the optimum time to perform the examination being 72 hours after the intravenous injection of 2 mCi 111In chelated to 2 mg bleomycin.Tumour uptake was visualized in 53 out of 62 scans in which tumour was present, but the extent of tumour was underestimated in seven cases, and over-estimated in five others. The latter were mostly due to uptake in infective lesions.These results indicate that the situations in which indium bleomycin is most likely to provide clinically relevant information are the distinction between recurrent tumour and post-radiotherapy changes in the thorax and pelvis, the diagnosis of recurrent carcinoma within the pelvis, and the distinction between bony metastases from carcinoma of the prostate and Paget's disease. Further clinical trials are necessary to assess these situations.

The distribution of 111In in the human body was studied after the injection of 111In-bleomycin for tumour localization. Uptake in body organs was measured by quantitative scanning using a dual detector scanner. The estimated absorbed dose from an injection of 1 mCi was 0·3 rad to the whole body, and approximately 1 rad to bone marrow, kidneys, liver and spleen.

Tissue distribution and excretion studies have been performed in rats and mice for up to 1 week after oral administration of 14C xylose and 14C mannose. The effective dose-equivalent is calculated to be 15 µSv/MBq for xylose and 120 µSv/MBq for mannose. Since there was no clearance of mannose during the period of the study, the effective dose-equivalent for mannose is almost entirely dependent upon the assumptions made about expected lifetime exposure.

A good correlation was found between relative uptake of 99Tcmdimercaptosuccinic acid (DMSA) and relative 131I orthoiodohippuric acid clearance in a group of 100 consecutive patients without evidence of renal failure. In the majority, attenuation correction was found to make no significant difference to relative function measurement. Those in whom it did could be readily identified by inspection of the posterior DMSA images at the time of examination. Two hundred patients were reviewed in whom serial studies had been performed over the previous 5 years. Differences in relative function greater than 5% indicated a high probability that a real change in renal function had occurred. We conclude that whilst renography and DMSA scintigraphy yield complementary information, relative function (L/L + R) can be measured equally well by either method, and the results are sufficiently reproducible to be clinically useful.

The prognostic significance of bone scintigraphy was investigated by following 587 consecutive patients with lung cancer, in whom this investigation had been performed, for up to 9 years, or until death. Survival was unrelated to age, sex or cell type. However, pain and abnormal bone scintigraphy were both independently associated with a significantly reduced survival compared with those who were free of pain or who had normal bone scintigraphy. These factors were cumulative. The association remained equally valid for all cell types. Claims that a single metastasis is not prognostically significant are unfounded. It is suggested that the results of some chemotherapy trials must be reconsidered in the light of present findings, because of the lack of adequate control groups; the results could be construed to show a beneficial effect only in patients with bone metastases and a poor prognosis, but little or no effect in patients with normal bone scintigraphy. As judged by clinical and radiological follow-up and post-mortem examination, skeletal scintigraphy in patients with lung cancer had a sensitivity of 0.89, a non-specificity (false positives/true negatives) of 0.00 and an accuracy of 0.78. With existing radiopharmaceuticals there is an irreducible residue of false negatives due to deposits which provoke little or no osteoblastic response. Bone scintigraphy is, thus, indicated in any patient with lung cancer with unexplained symptoms and whenever staging is required, because of the prognostic implications. It should precede other staging investigations because the high detection rate may render other tests unnecessary.

Radioisotope scintigraphy of the kidney and intravenous urography have been compared in 79 children with bacteriologically proven urinary tract infections, followed up over a period of between one and four years. Both techniques were in agreement as to the presence or absence of an abnormality, and the extent of any abnormality present, in 93.5% of the kidneys studied. There was a discrepancy in ten kidneys.Excretion urography has a sensitivity of 0.86 and a specificity of 0.92 in the detection of pyelonephritic scarring in children. Radioisotope scintigraphy has a sensitivity of 0.96 and a specificity of 0.98. It is therefore concluded that radioisotope scintigraphy is the preferred technique.

Indirect voiding radionuclide cystourethrography has been compared with micturating cystourethrography in 57 children with urinary tract infections. A quasi-quantitative technique utilizing a mini-computer to optimize the images from the gamma camera has been shown to be at least as sensitive as conventional radiological techniques but to give these results without catheterization, at a lower radiation dose and at lower cost.

The relatively high cost of nuclear-medicine equipment has produced a situation in which a service is provided centrally, patients being transferred from smaller or outlying hospitals. The disadvantages of inter-hospital transfer of the ill patient, the inability to perform investigations on those too ill to travel, and the man-hours involved escorting patients, prompted this study to assess both the technical feasibility and the possible clinical advantages of providing a transportable nuclear-medicine service. This paper is concerned solely with technical aspects of the project, concentrating on its initial design and the results obtained in the first six months.At the planning stage in 1977 a choice had to be made between transporting a mobile gamma camera which could be off-loaded from a small van and driven into the hospital, or a static gamma camera permanently positioned in a large van, similar to the mass X-ray service or mobile whole-body counter (Boddy, 1967). The former approach was adopted for the following reasons: the quality of images from a mobile gamma camera was as good as that of images from a static camera, the transporting vehicle would be much cheaper, the driver would not require an HGV licence and finally the patients would not have to be brought outside the hospital.

A 7-year-old girl presented in August 1983 with a 4-month history of diffuse limb pains, loss of weight and general malaise. The pain had commenced in the neck and progressed to involve the right shoulder, both legs and spine. Examination revealed two firm right-sided cervical lymph nodes, 1 cm in diameter, and some smaller, firm nodes palpable over the occiput and in the inguinal regions. There was diffuse abdominal tenderness in the left upper quadrant but no other abnormal findings.Initial investigation showed a haemoglobin level of 7.9 g/dl (normochromic film), white cell count 5.9 x 109/1, ESR 90 mm in 1 h. Twenty-four-hour assay of 4-hydroxy-3-methoxymandolate was increased above 30 µmol/24 h (normal laboratory range < 30 µmol). Metadrenalin assay was 3.7/µmol/24h (normal laboratory range up to 7 µmol). Cystathionine was not detected in the urine. Chest radiography showed an enlarged left hilum associated with extensive paravertebral widening, and abdominal radiography showed calcification in the right suprarenal region. Skeletal survey identified multiple lytic areas involving mainly the metaphyses of the long bones and skull vault. There was a calcified area anterior to the pole of the right kidney on ultrasonography and also a left paravertebral mass indenting the pelvis of the left kidney. Bone marrow aspiration confirmed marrow involvement with tumour cells occupying some 40% of the nucleated cells. Metastatic neuroblastoma was diagnosed from cervical node biopsy. The primary was presumed to be within the right adrenal gland.

The report of distribution and dosimetry of 67Ga by Saunders, Taylor and Trott (1973) was based on uptake measurements estimated from biopsy samples. Estimates of liver weight are notoriously difficult to make, and in each patient samples could be obtained on one occasion only.

This is the second edition of volume six in this well-known series, many of the other volumes of which are associated with the name of Dr. Lucy Squire. It is eleven years since the first edition, and little if anything of the original remains beyond the format—a synoptic introduction to each chapter, followed by a number of examples based on true cases. Each case is illustrated where appropriate by selected radiographs and ultrasound scans in addition to scintigrams.

This neat little book, written by a neuroradiologist, a general radiologist and a physicist, sets out with the intention of providing an introduction to radioisotope imaging for candidates for the D.M.R. and F.R.C.R. examinations. Between them the authors have a good deal of personal experience both of radioisotope imaging and of teaching candidates for these examinations, and their joint experience has been put to good use. It is well written and well produced, with concise, clear chapters and restricted but pertinent illustrations.

In the preface to this monograph the authors declare that it is meant to reflect the role of the spleen in the various disorders discussed, without any attempt at a complete consideration of other aspects of the diseases.Most common non-infectious conditions in which the spleen may be involved are mentioned, although in many cases the descriptions would be barely adequate for a medical student reading for finals, and of no interest to any post-graduate.

A well-cultivated museum should provide the student or visitor with a distillation of the accumulated experience of the department housing it. An atlas may be regarded as a condensation of a museum, with more stringent limitations of space and available to a much larger, unselected audience.

This, the latest edition of a well known annual, maintains the high standards set by the earlier editions and will enhance the high reputation obtained by them. The editors have clearly given each of the writers a precisely defined and well considered brief and all have been effectively executed. The field has been widened to include one paper on magnetic resonance imaging of the heart, and there is one on single photon emission tomography, a topic which, although it has been of interest for some years, is only now beginning to reveal its true clinical potential.

We are pleased to find that Meller et al.(1980) are in broad agreement with us with regard to the usefulness and indications for IVRC, and to hear of their comparative study of eight refluxing ureters, but would like to make a few comments.