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J R Buscombe

Publications and source records attributed to J R Buscombe.

67 records · Page 4Linked to original sources
PubMed1993

Reporting ventilation-perfusion lung scintigraphy: impact on subsequent use of anticoagulation therapy.

Ventilation and perfusion lung scintigraphy is an established and safe noninvasive technique which has been used for nearly 30 years to establish the diagnosis of pulmonary embolism. Recently, in common with other diagnostic tests, there has arisen the need to reassess the effectiveness of this test in the clinical setting. A retrospective analysis of 244 patients undergoing ventilation-perfusion lung scintigraphy was performed. A total of 203 case notes were available. It was found that the majority of reports (68.5%) were described as either high probability for the presence of pulmonary embolism or normal or low probability. A result of 'high probability' changed the clinical management of the patient in 28/46 (61%) of reported cases but in only 5/91 (5.5%) of patients reported as 'normal' or 'low probability'. During the study there were six deaths, five from other causes and one from pulmonary embolism; this patient died despite anticoagulation following a 'high probability' ventilation-perfusion lung scintigraphy. Ventilation-perfusion lung scintigraphy is a safe and effective noninvasive method to diagnose the presence of pulmonary embolism and a test which has a significant effect on patient management.

Adolescent↗
PubMed1993

Clinical high resolution skeletal single photon emission tomography using a triple-headed gamma camera.

Planar skeletal scintigraphy has become established as a standard diagnostic test performed within the nuclear medicine department. Since the 1970s good quality images have been produced using an Anger gamma camera and 99Tcm-labelled diphosphonates. Single photon emission tomography (SPET) has improved the sensitivity of detection and the ability to localize bony pathology, particularly benign bone disease in the spine. Recently multi-detector gamma cameras dedicated to SPET have become available. One such system, the Toshiba GCA-9300A, has been used to perform routine clinical skeletal SPET in 81 patients. Good quality images have been obtained using an 8 min acquisition in the axial skeleton and a 16 min acquisition protocol in the peripheral skeleton. Multiple sites can be tomographed in the same patient during the same examination using two or more 8 min acquisitions. Such a multi-detector gamma camera offers advantages over the standard single-headed rotating camera for skeletal SPET in terms of both imaging time and image quality. A cost analysis was performed which demonstrated that the additional cost of purchasing such a multidector gamma camera was less than 30.00 pounds per SPET study.

Bone Neoplasms↗
PubMed1993

Indium-111-labeled polyclonal human immunoglobulin: identifying focal infection in patients positive for human immunodeficiency virus.

Pooled human immunoglobulin labeled with indium-111 (111In-HIgG) was used to identify the presence and extent of infection in patients positive for human immunodeficiency virus (HIV), presenting with either symptoms and/or signs of acute chest infection or with pyrexia without localizing signs or symptoms. Fifty-five studies were performed in 51 patients with suspected chest infection or pyrexia without localizing signs. Of these, 111In-HIgG identified intrapulmonary accumulation in 17 patients with Pneumocystis carinii pneumonia, eight with bacterial pneumonia, five with cytomegalovirus pneumonia, three with pulmonary Mycobacterium avium intracellulare infection and one with a fungal pneumonia. There was no intrapulmonary accumulation of 111In-HIgG in five patients with bronchopulmonary Kaposi's sarcoma and in three patients with intrathoracic lymphoma. Quantification of lung/heart activity was significantly increased (p < 0.05) in patients with active chest infection compared with those with intrapulmonary tumor or no active lung pathology. Indium-111-HIgG scintigraphy also localized at 14 sites of extrapulmonary infection, including six patients with colitis. There were no false-negative studies but false-positive uptake was seen in four studies. These results confirm that 111In-HIgG correctly identifies the presence and extent of infection in patients positive for HIV antibody.

AIDS-Related Opportunistic Infections↗
PubMed1992

The use of thallium-201 lung/heart ratios.

This survey gives an overview of the methodology of thallium-201 lung/heart uptake ratios often used as an independent factor in the assessment of patients with coronary artery disease undergoing myocardial perfusion scintigraphy. Different techniques have been used in the past. The most sensitive method is one which calculates a lung/heart ratio from scintigraphy obtained immediately after cessation of exercise. If single photon emission tomography (SPET) is routinely performed the anterior projection of the data set obtained during tomographic acquisition should be used in preference to a separate planar anterior static images recorded before or after the SPET procedure. The lung/heart ratio is useful as a prognostic indicator of outcome as it accurately mimics the degree of left ventricular dysfunction. With the increasing popularity of pharmacological stress testing there is evidence that this ratio still offer valid information. Additional work in this field is nevertheless required to further confirm this observation. In routine clinical practice, the lung/heart ratio should help and enable physicians to prioritise patients for urgent intervention.

Coronary Disease↗
PubMed1992

Hepatobiliary scintigraphy in the diagnosis of AIDS-related sclerosing cholangitis.

Twenty human immunodeficiency virus (HIV)-positive patients were studied who presented with right upper quadrant abdominal pain, with or without abnormal biochemical liver function tests, in whom AIDS-related sclerosing cholangitis (ASC) was suspected. The results obtained from hepatobiliary scintigraphy using 99Tcm-IODIDA were compared with data from endoscopic retrograde cholangiopancreatography (ERCP), ultrasound and histological data from liver biopsy or post mortem. 99Tcm-IODIDA was abnormal in 14 patients. Liver biopsy, ERCP or post mortem confirmed ASC in 11 patients of whom 10 had an abnormal 99Tcm-IODIDA study. Ultrasound was performed in eight of the patients with confirmed ASC but was abnormal in only five of these. One patient with mild ASC on ERCP and Kaposi's sarcoma had a normal 99Tcm-IODIDA. In HIV-positive patients with right upper quadrant pain, imaging with 99Tcm-IODIDA provides a non-invasive screening test which may help to determine those patients who should be referred for ERCP.

Acquired Immunodeficiency Syndrome↗
PubMed1992

Assessment of myocardial viability with 201Tl SPET and reinjection technique: a quantitative approach.

The definition of viable myocardium after an acute myocardial infarction (MI) is important as it will determine which therapeutic option will be best for the patient. In 201Tl scintigraphy it has been shown that late redistribution (8-24 h) or reinjection may help to identify viable myocardium which does not appear to reperfuse on the 4 h redistribution image. In a prospective study 20 patients with a persistent defect seen on both stress and redistribution images were imaged after reinjection of 201Tl. On visual analysis a total of 180 segments were studied, 85 were normal, 18 reperfused at redistribution and a further nine (in six patients) after reinjection. Bull's-eye analysis at stress demonstrated a mean defect size of 279 pixels, S.D. +/- 74. After redistribution, there was no significant change in mean defect size (227 +/- 96 pixels). At reinjection, there was a significant reduction in mean defect size (189 +/- 107 pixels) (P < 0.05, paired 't'-test). Quantification shows a significant reduction in defect size between stress and reinjection. The use of the 201Tl reinjection technique in patients with a fixed perfusion deficit on stress and redistribution images improves the detection of viable myocardium and is to be preferred to a method of redistribution analysis alone.

Adult↗
PubMed1991

Combined 67Ga citrate and 99Tcm-human immunoglobulin imaging in human immunodeficiency virus-positive patients with fever of undetermined origin.

Patients infected with the human immunodeficiency virus (HIV) suffer from serious and life-threatening infections. These patients often present with pyrexia but without localizing signs. Despite its high sensitivity in identifying focal infection 67Ga citrate scintigraphy lacks specificity; lymphoma and solid tumours may also be imaged. This presents particular problems in HIV-positive patients with pyrexia where the differential diagnosis is often between infection and lymphoma. In an attempt to improve the specificity of radionuclide imaging in these patients a combination of 67Ga citrate and the new agent 99Tcm-labelled human immunoglobulin (99Tcm-HIG) was used in 25 patients who were sequentially imaged with the two agents. Fourteen patients had 29 sites of microbiologically confirmed infection; 67Ga citrate identified 27 sites and 99Tcm-HIG identified 16 sites. Seven of the nine sites visualized with 99Tcm-HIG, but positive with 67Ga citrate, were intrathoracic. Abnormal concentration of 67Ga citrate, not due to infection, occurred at eight sites; five lymphoma, one gout, one recent fracture and one patient with prominent bone marrow islands. 99Tcm-HIG showed increased concentration of tracer in only one of the patients with lymphoma. A combination of 67Ga citrate and 99Tcm-HIG imaging in HIV-positive patients with pyrexia of unknown origin enables a differentiation between infection and lymphoma to be made more readily. The poor sensitivity of 99Tcm-HIG in the chest will limit its sole use in this patient group.

Adult↗
PubMed1990

99mTc-human immunoglobulin (HIG)--first results of a new agent for the localization of infection and inflammation.

Technetium (99mTc) labelled, polyclonal human immunoglobulin (HIG) is a new agent that detects focal infection and inflammation. This new agent was compared in 40 patients with the accepted standard, namely 111In-oxine-labelled leucocytes. This comparison resulted in a sensitivity of 94% and a specificity of 96% for 99mTc-HIG when 111In-oxine leucocytes were defined as giving the true result. The new agent was shown to localize both sepsis and active inflammatory bowel disease (IBD). There was 100% concordance in the 16 patients with IBD who were imaged with both 99mTc-HIG and 111In-oxine leucocytes. Discordant results were obtained in one case of suspected osteomyelitis, which was false-positive on the 99mTc-HIG scan, and one case of pyrexia of unknown origin when the 99mTc-HIG was false-negative and the 111In-oxine leucocyte scan demonstrated accumulation of tracer in the caecum at 24 h post-injection. Normal distribution for 99mTc-HIG demonstrated activity in the kidneys and bladder and that 50% of the tracer is cleared through the kidneys during the first 24 h post-injection. There were no major or minor side-effects.

Bacterial Infections↗
PubMedDate not supplied

Correlation between uptake of Tc-99m sestaMIBI and prognostic factors of breast cancer.

UNLABELLED: The purpose of this retrospective study was assessment of correlation between Tc-99m sestaMIBI uptake and some prognostic factors of breast cancer. The following prognostic factors have been included in this study: size of the tumour, age of the patients, axilla node involvement, oestrogen and progesterone receptor (ER, PR) status, grading system of Bloom-Richardson and Ki-67 antigen expression. METHODS: 79 patients were enrolled in this study, with 85 lesions confirmed as primary breast cancers. Mean age of patients was 53 years. Scintimammography (SMM) was performed after intravenous injection of 740MBq. At 5-10 min after injection standard planar images were obtained in prone lateral and anterior supine views. Assessment of correlation between known prognostic factors of breast cancer and uptake of MIBI (evaluated as a tumour to background ratio-TBR) was performed used non-parametric (Kendall-tau correlation) statistical analysis. RESULTS: There were 85 breast cancers (73 invasive ductal carcinomas, 11 DCIS (ductal carcinoma in situ) and 1 lobular carcinoma. There was positive correlation between TBR Tc-99m MIBI uptake and size of the tumour (t = 0.19, p = 0.01), presence of axilla node involvement (t = 0.2, p = 0.006) and also grade of the IDC tumours evaluated using Bloom-Richardson's criteria (t = 0.18, 0.03). There were negative correlation between TBR and presence of PR (t = -0.16, p = 0.02) and borderline negative correlation between TBR and age of patients (t = -0.137, p = 0.06) and also TBR and ER status (t = -0.135, p = 0.065). Patients who are younger and/or have PR or ER negative cancers have higher Tc-99m MIBI uptake. Patients who presented with high grade of malignancy (B-R) also have higher uptake of radiotracer. Also those with higher uptake of radiotracer often had axillary node involvement. This would suggest that more aggressive tumours have higher uptake of Tc-99m MIBI. Finally this study suggest correlation between in vivo uptake of MIBI and some of the known prognostic factors of breast cancer.

Breast Neoplasms↗
PubMedDate not supplied

Uptake of Tc-99m MIBI related to tumour size and type.

The accuracy of Tc-99m MIBI scintimammography depends on the uptake in cancer cells being greater than surrounding normal tissue. The aim of this study was to determine which were the dominant factors affecting uptake of Tc-99m MIBI in breast cancer cells in vivo. The tumour to background ratio (TBR) was measured in 74 focal breast lumps occurring in 70 women, of whom 53 had breast cancer. In patients with breast cancer the TBR was compared in those under and over 45, those with tumours over and under 20 mm, those who had auxiliary disease, the histological type of the tumour and whether ductal on the Bloom Richardson scale. The only factor which appeared to have an influence on uptake of Tc-99m MIBI was the histological type of the tumour. Ductal carcinomas had a mean TBR of 2.07, significantly greater than either other types of breast cancer (TBR = 1.31) and benign tumours (TBR = 1.46). The histological type of tumour appears to be the dominant factor affecting uptake of Tc99m MIBI in vivo.

Adult↗