PubMed Health⌕ Search

Biomedical subjects

W Tindale

Publications and source records attributed to W Tindale.

11 recordsLinked to original sources

Procedure guidelines for radionuclide myocardial perfusion imaging.

Radionuclide myocardial perfusion imaging (MPI) is an established and non-invasive imaging technique with diagnostic and prognostic efficacy in the investigation of coronary artery disease. It is the only widely available test for assessing myocardial perfusion directly but there are variations in the way it is performed in different centres. Harmonization of practice, at least at a national level, is therefore essential, and clinical governance now makes it mandatory for practice to be based upon evidence whenever possible [ 1]. This is best achieved by expert analysis of the evidence and to this end the British Nuclear Cardiology Society (BNCS) in association with the British Cardiac Society (BCS) and the British Nuclear Medicine Society (BNMS) have developed procedure guidelines for tomographic myocardial perfusion imaging. A systematic literature search was performed and every effort was made to conform with the AGREE recommendations [ 2]. All recommendations are therefore based on either evidence from clinical studies, previous published guidelines or expert consensus of the writing and advisory groups. The guidelines cover the clinical indications of MPI, the methods used for stress testing, the radiopharmaceuticals and the injected activities and also issues related to acquisition, processing and interpretation of images. They do not cover the benefits or drawbacks of the technique in specific circumstances; neither do they address its cost effectiveness in clinical diagnosis and management nor its potential impact on clinical outcomes. The guidelines aim to assist medical practitioners and other health care professionals in recommending, performing, interpreting and reporting single photon emission computed tomography (SPECT) of myocardial perfusion.

Coronary Artery Disease↗

Radioiodine therapy: care of the helpless patient and handling of the radioactive corpse.

Nurses caring for a helpless patient following a nominal 800 MBq administration of radioiodine were concerned about their radiation dose. Using published data, a nurse could receive an estimated 650 microSv per shift. A regime to restrict their dose was planned using a 500 microSv dose constraint. Thermoluminescent dosimeters indicated a maximum whole-body effective dose of 250 microSv. Three days post 131I administration the patient died (estimated activity in the body 400 MBq). A minimum delay of two weeks was advised prior to a post-mortem. Special precautions were issued to minimise contamination. Dose rates (microSv h(-1)), measured one day after the patient died, at the level of the thyroid, chest and bladder at 0.01 m from the corpse were 1800, 290 and 73 respectively. At 1.0 m the dose rate was 26 microSv h(-1) at all levels. The pathologist was estimated to have received a maximum whole-body dose of 400 microSv during the post-mortem. Contamination measurements (Bq cm(-2)) made following the post-mortem were as follows: pathologist's hands 5, clothes 0, towels 1.8, saw 5, instruments 0.5, plastic sheet 0.8, scales 0.4 and floors/walls 1.1. These data indicate that with appropriate radiation protection guidelines, staff can be reassured that their doses in these circumstances are very low.

Cadaver↗

Quantitative bone scintigraphy in reflex sympathetic dystrophy.

We have investigated the appearances of the technetium-99m labelled methylene diphosphonate bone scan in 29 scans performed in 16 patients with post-fracture reflex sympathetic dystrophy (RSD) of the hand. There was a close correlation between increased uptake in the metacarpophalangeal joints and the metacarpal bones, suggesting that the increased uptake in RSD is not confined to the periarticular areas as has been previously reported but occurs throughout the affected region. In seven cases examined 3 months after fracture, RSD was associated with a significant increase in uptake at all sites in the hand on the delayed scan which was not seen in matched post-fracture controls, confirming that increased uptake on delayed bone scintography is a sensitive test for the presence of RSD even in the presence of a fracture of the wrist. The early increased uptake gradually returned to normal. Local tenderness assessed by dolorimetry was correlated with increased uptake, suggesting that the bone scan is not only useful as a diagnostic tool but also provides a quantitative indication of the severity of the condition which may be useful in planning and assessing treatments.

Bone and Bones↗

Effects of five daily 1 h infusions of alendronate in Paget's disease of bone.

We report a randomized placebo-controlled double-blind study of amino-hydroxybutylidene bisphosphonate (alendronate), infused over 1 h, in 15 patients with Paget's disease of bone. Alendronate, 10 mg/day for 5 days, suppressed urinary hydroxyproline to 44.9 +/- 4.8% and serum alkaline phosphatase to 74.6 +/- 5.4% of their pretreatment values within 1 month of the start of treatment. Within 5 months of the start of treatment serum alkaline phosphatase fell to 47.9 +/- 6.3% of pretreatment values. These effects were associated with a decrease in serum calcium and phosphate and in urinary calcium excretion and with a rise in serum iPTH values. A transient fever was observed in 3 of 10 patients who received alendronate during the course of the infusions, and this was associated with a decrease in the total and differential white cell count. No adverse effects were noted on renal function as judged by glomerular filtration rate and indices of proximal and distal tubular function. This regimen may simplify the management of patients with Paget's disease of bone.

Aged↗

Broadband ultrasound attenuation in the os calcis: relationship to bone mineral at other skeletal sites.

1. We have examined the relationship between broadband ultrasound attenuation in the os calcis and measurements of bone mineral in the distal forearm and lumbar spine of normal and postmenopausal osteoporotic women. 2. Values of broadband ultrasound attenuation in postmenopausal women with vertebral osteoporotic fractures were significantly lower (35%) than in normal pre- and peri-menopausal women (55.4 +/- 3.8 and 79.6 +/- 0.8 dB/MHz, respectively). 3. Broadband ultrasound attenuation correlated significantly with bone mineral content measured in the distal forearm by single-photon absorptiometry (r = 0.77, P less than 0.0001) and with bone mineral content (r = 0.66, P less than 0.0001) and bone mineral density (r = 0.72, P less than 0.0001) measured in the lumbar spine by dual-photon absorptiometry. 4. Although significant, these correlations are not sufficiently close to be predictive. However, the accuracy of broadband ultrasound attenuation in discriminating between normal subjects and patients with vertebral fracture compared very favourably with direct measurements in the spine by dual-photon absorptiometry. 5. Broadband ultrasound attenuation, but not the other measurements, correlated significantly with age in the osteoporotic patients (r = 0.50, P less than 0.05). 6. These findings may reflect the partial dependence of broadband ultrasound attenuation on the intrinsic trabecular architecture of cancellous bone, the disruption of which contributes to an increase in fracture risk.

Absorptiometry, Photon↗

A new porcine bioprosthesis: in vitro and in vivo evaluation.

The Wessex porcine bioprosthesis exhibits satisfactory hydrodynamic performance and durability comparable to other clinical porcine valves. In vivo performance and pathological studies of explanted valves confirm adequate biodurability and haemodynamic performance. Early clinical results are satisfactory and encourage further study.

Angiography↗