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J Bomanji

Publications and source records attributed to J Bomanji.

At least 19 recordsLinked to original sources
PubMed2005

Clinical evaluation of 2D versus 3D whole-body PET image quality using a dedicated BGO PET scanner.

PURPOSE: Three-dimensional positron emission tomography (3D PET) results in higher system sensitivity, with an associated increase in the detection of scatter and random coincidences. The objective of this work was to compare, from a clinical perspective, 3D and two-dimensional (2D) acquisitions in terms of whole-body (WB) PET image quality with a dedicated BGO PET system. METHODS: 2D and 3D WB emission acquisitions were carried out in 70 patients. Variable acquisition parameters in terms of time of emission acquisition per axial field of view (aFOV) and slice overlap between sequential aFOVs were used during the 3D acquisitions. 3D and 2D images were reconstructed using FORE+WLS and OSEM respectively. Scatter correction was performed by convolution subtraction and a model-based scatter correction in 2D and 3D respectively. All WB images were attenuation corrected using segmented transmission scans. Images were blindly assessed by three observers for the presence of artefacts, confidence in lesion detection and overall image quality using a scoring system. RESULTS: Statistically significant differences between 2D and 3D image quality were only obtained for 3D emission acquisitions of 3 min. No statistically significant differences were observed for image artefacts or lesion detectability scores. Image quality correlated significantly with patient weight for both modes of operation. Finally, no differences were seen in image artefact scores for the different axial slice overlaps considered, suggesting the use of five slice overlaps in 3D WB acquisitions. CONCLUSION: 3D WB imaging using a dedicated BGO-based PET scanner offers similar image quality to that obtained in 2D considering similar overall times of acquisitions.

Aged↗
PubMed2004

Small cell lung cancer associated with anti-Hu paraneoplastic sensory neuropathy and peripheral nerve microvasculitis: case report and literature review.

A 53-year-old man presented with an 8-week history of upper and lower limb paraesthesia. Neurological examination revealed a glove and stocking distribution of sensory loss. Sural nerve biopsy showed severe axonal neuropathy associated with microvasculitis. Positron-emission tomography and thoracic computed tomography helped in localising the underlying malignancy. A transbronchial biopsy confirmed the diagnosis of small cell lung carcinoma (SCLC). Neuroimmunological studies identified anti-Hu antibodies and confirmed a paraneoplastic aetiology for his neuropathy. Treatment of small cell lung cancer with carboplatin and etoposide resulted in significant improvement of neurological symptoms. We report a case of a patient with SCLC and anti-Hu paraneoplastic sensory neuropathy with microvasculitis, and discuss the literature on prognosis of patients with SCLC with paraneoplastic neurological syndromes compared with patients with SCLC only.

Autoantibodies↗
PubMed2003

Positron emission and computed X-ray tomography: a coming together.

We describe the introduction of positron emission tomography/computed tomography (PET/CT) to the investigation of patients with cancer. The first such unit in the UK and its mode of operation is discussed and initial applications shown. Five hundred and thirty-five patients have been scanned with 2-[18F]fluoro-2-deoxy-D-glucose from mid-January 2002 to the end of August 2002. From this initial experience a clear view of the impact of this technology is emerging. It can now be stated that (1) PET/CT does speed up the throughput of patient studies by at least 25% and hence adds to the comfort of patients scanned; and (2) PET/CT leads to greater accuracy in the interpretation of data. In view of the routine availability of high quality PET and CT fused maps a significant development in radiotherapy planning is on the horizon. We discuss our experience at present and point to further developments in the near future.

Equipment Design↗
PubMed2002

CT-based attenuation correction in the calculation of semi-quantitative indices of [18F]FDG uptake in PET.

The introduction of combined PET/CT systems has a number of advantages, including the utilisation of CT images for PET attenuation correction (AC). The potential advantage compared with existing methodology is less noisy transmission maps within shorter times of acquisition. The objective of our investigation was to assess the accuracy of CT attenuation correction (CTAC) and to study resulting bias and signal to noise ratio (SNR) in image-derived semi-quantitative uptake indices. A combined PET/CT system (GE Discovery LS) was used. Different size phantoms containing variable density components were used to assess the inherent accuracy of a bilinear transformation in the conversion of CT images to 511 keV attenuation maps. This was followed by a phantom study simulating tumour imaging conditions, with a tumour to background ratio of 5:1. An additional variable was the inclusion of contrast agent at different concentration levels. A CT scan was carried out followed by 5 min emission with 1-h and 3-min transmission frames. Clinical data were acquired in 50 patients, who had a CT scan under normal breathing conditions (CTAC(nb)) or under breath-hold with inspiration (CTAC(insp)) or expiration (CTAC(exp)), followed by a PET scan of 5 and 3 min per bed position for the emission and transmission scans respectively. Phantom and patient studies were reconstructed using segmented AC (SAC) and CTAC. In addition, measured AC (MAC) was performed for the phantom study using the 1-h transmission frame. Comparing the attenuation coefficients obtained using the CT- and the rod source-based attenuation maps, differences of 3% and <6% were recorded before and after segmentation of the measured transmission maps. Differences of up to 6% and 8% were found in the average count density (SUV(avg)) between the phantom images reconstructed with MAC and those reconstructed with CTAC and SAC respectively. In the case of CTAC, the difference increased up to 27% with the presence of contrast agent. The presence of metallic implants led to underestimation in the surrounding SUV(avg) and increasing non-uniformity in the proximity of the implant. The patient study revealed no statistically significant differences in the SUV(avg) between either CTAC(nb) or CTAC(exp) and SAC-reconstructed images. The larger differences were recorded in the lung. Both the phantom and the patient studies revealed an average increase of approximately 25% in the SNR for the CTAC-reconstructed emission images compared with the SAC-reconstructed images. In conclusion, CTAC(nb) or CTAC(exp) is a viable alternative to SAC for whole-body studies. With CTAC, careful consideration should be given to interpretation of images and use of SUVs in the presence of oral contrast and in the proximity of metallic implants.

Algorithms↗
PubMed2002

Fluorodeoxyglucose positron emission tomography in clinical oncology: the referrer's perspective.

From January 2000 to April 2002 a prospective audit based on a questionnaire was carried out concerning the attitudes and viewpoints of clinicians referring patients to fluorodeoxyglucose positron emission tomography (FDG PET) scanning. A standard and structured audit form was posted to each referring doctor with the formal clinical report issued by the nuclear medicine consultant. Three hundred and thirty evaluable forms were analysed, a return rate of approximately 22%, from a total of 1500 PET patients studied during this period. FDG PET scanning was deemed by the referring physician to have altered the staging of cancer patients in 39% of all cases. Twenty-five per cent of patients were upstaged with FDG PET and 14% of patients downstaged. Patient management was changed in 39% of cases whilst a change in treatment occurred in 10% of cases. The reported FDG PET study was judged as being helpful in over 75% of all cases. These data further support evidence of the increasing role of FDG studies in the investigation of patients with cancer.

Adolescent↗
PubMed2001

Influence of OSEM and segmented attenuation correction in the calculation of standardised uptake values for [18F]FDG PET.

Standardised Uptake Values (SUVs) are widely used in positron emission tomography (PET) as a semi-quantitative index of fluorine-18 labelled fluorodeoxyglucose uptake. The objective of this study was to investigate any bias introduced in the calculation of SUVs as a result of employing ordered subsets-expectation maximisation (OSEM) image reconstruction and segmented attenuation correction (SAC). Variable emission and transmission time durations were investigated. Both a phantom and a clinical evaluation of the bias were carried out. The software implemented in the GE Advance PET scanner was used. Phantom studies simulating tumour imaging conditions were performed. Since a variable count rate may influence the results obtained using OSEM, similar acquisitions were performed at total count rates of 34 kcps and 12 kcps. Clinical data consisted of 100 patient studies. Emission datasets of 5 and 15 min duration were combined with 15-, 3-, 2- and 1-min transmission datasets for the reconstruction of both phantom and patient studies. Two SUVs were estimated using the average (SUVavg) and the maximum (SUVmax) count density from regions of interest placed well inside structures of interest. The percentage bias of these SUVs compared with the values obtained using a reference image was calculated. The reference image was considered to be the one produced by filtered back-projection (FBP) image reconstruction with measured attenuation correction using the 15-min emission and transmission datasets for each phantom and patient study. A bias of 5%-20% was found for the SUVavg and SUVmax in the case of FBP with SAC using variable transmission times. In the case of OSEM with SAC, the bias increased to 10%-30%. An overall increase of 5%-10% was observed with the use of SUVmax. The 5-min emission dataset led to an increase in the bias of 25%-100%, with the larger increase recorded for the SUVmax. The results suggest that OSEM and SAC with 3 and 2 min transmission may be reliably used to reduce the overall data acquisition time without compromising the accuracy of SUVs.

Fluorodeoxyglucose F18↗
PubMed1998

Technetium-99m human immunoglobulin imaging in patients with subacromial impingement or adhesive capsulitis.

Although recognised as useful in detecting soft-tissue inflammation and infection, technetium-99m human immunoglobulin (Tc-99m HIG) has not been widely studied in evaluating regional inflammatory musculoskeletal conditions. Tc-99m HIG scintigraphy was undertaken for consecutive patients referred to a rheumatology clinic with unilateral shoulder pain, diagnosed with either subacromial impingement (n = 12) or adhesive capsulitis (n = 4) from clinical examination, radiographic, and in some cases arthrographic findings. In all patients there were no differences in Tc-99m HIG images between symptomatic and asymptomatic shoulders. The findings are discussed, with reference to patterns of tissue inflammation which have been associated with each of the two conditions and in the context of patients referred to hospital relatively late after onset of symptoms (4-6 months).

Bursitis↗
PubMed1998

Biodistribution of a radiolabelled monoclonal antibody NY3D11 recognizing the neural cell adhesion molecule in tumour xenografts and patients with small-cell lung cancer.

The neural cell adhesion molecule (NCAM) is highly expressed on the surface of small-cell-lung cancer (SCLC) cells. We have produced a monoclonal antibody, NY3D11, that binds to NCAM to investigate whether this antigen could be used to develop antibody-directed therapy for SCLC. 125I-labelled IgG and F(ab')2 fragments of NY3D11 localized selectively in human SCLC xenografts grown in nude mice. The human biodistribution of 131I-labelled NY3D11 after intravenous administration was investigated by gamma-camera imaging in six patients with SCLC. Three patients received IgG and three received F(ab')2. No evidence of localization to primary tumours or metastases was seen and antibody accumulated rapidly in the liver and bone marrow. The probable explanation for this distribution is that NY3D11 reacted with soluble NCAM or natural killer cells that possess the CD56 (NCAM) antigen.

Adult↗
PubMed1997

Clinical evaluation of technetium-99m infecton for the localisation of bacterial infection.

The aim of the study was to distinguish infection from inflammation in patients with suspected infection using technetium-99m Infecton. Ninety-nine patients (102 studies) referred for infection evaluation underwent imaging with 400 MBq 99mTc-Infecton at 1 and 4 h. Most patients had appropriate microbiological tests and about half (56) had radiolabelled white cell scans as well. No adverse effects were noted in any patient. The clinical efficacy of 99mTc-Infecton depended in part on whether imaging was undertaken during antibiotic therapy for infection or not. In consultation with the microbiologist, 5-14 days of appropriate and successful antibiotic therapy was considered adequate to classify some results as true-negatives. The figures for sensitivity and specificity of 99mTc-Infecton for active or unsuccessfully treated infection were 83% and 91% respectively. It is concluded that 99mTc-Infecton imaging contributed to the differential diagnosis of inflammation. It is being used as the first imaging modality when bacterial infection is suspected.

Adolescent↗
PubMed1997

Technetium-99m-MDP patterns in patients with painful shoulder lesions.

UNLABELLED: There is no consensus on the optimum mode of imaging in patients with painful shoulder lesions. There is a particular paucity of scintigraphic data. As a result, the strengths and weaknesses of scintigraphy cannot be adequately compared to other imaging techniques used in shoulder imaging. This study evaluated whether specific patterns of scintigraphic abnormality could be detected in patients with painful shoulders seen in rheumatological practice using 99mTc-methylene diphosphonate (MDP). METHODS: Scintigraphic abnormalities were recorded in consecutive patients presenting to a rheumatology clinic with unilateral shoulder pain. Patients were subdivided according to patterns of clinical abnormality consistent with a working diagnosis of a lesion located in the subacromial region, adhesive capsulitis (frozen shoulder) or a lesion likely to be located in the glenohumeral joint. Patterns of radiopharmaceutical distribution in different regions of the shoulder were evaluated in the light of clinical data and the results of shoulder radiographs. RESULTS: Technetium-99m-MDP scans were abnormal in 19 of 24 (79%) patients, and radiographs were abnormal in 8 of 24 (33%) patients. Distinct patterns of 99mTc-MDP image abnormality were identified: an increase in 99mTc-MDP uptake in the coracoid, acromion and medial humeral head on anterior planar images, together with an absence of posterior planar image abnormality, frequently occurred in association with a working diagnosis of a lesion located in the subacromial region. Posterior planar 99mTc-MDP image abnormalities always occurred in patients with clinical features consistent with a diagnosis of adhesive capsulitis. There was an 85% agreement between two observers' scores when 99mTc-MDP distribution in specific shoulder regions was graded. CONCLUSION: Distinct patterns of 99mTc-MDP distribution may be associated with clinically-distinct patterns of abnormality in patients with painful shoulder lesions. Further studies to elucidate a role for 99mTc-MDP scintigraphy in this patient group are warranted.

Humans↗
PubMed1996

Comparison of 99mTc infecton imaging with radiolabelled white-cell imaging in the evaluation of bacterial infection.

BACKGROUND: Bacterial infection can pose a substantial diagnostic dilemma. Techniques involving radiolabelled leucocytes can pinpoint the site of inflammation. However, previous radiolabelling techniques have failed to distinguish between bacterial-mediated infection and non-bacterial inflammation. To overcome this difficulty, we have studied a radiopharmaceutical, technetium-99m (99mTc) Infecton, which is based on the antibiotic ciprofloxacin. METHODS: We used this agent to image bacterial infection in 56 patients (one twice) with known or suspected sites of infection. We then compared the imaging results of these patients with those from a radiolabelled leucocyte study. FINDINGS: The concordance rate was 68% (39 out of 57 images). In 18 discordant results 99mTc Infecton was correctly positive in 8 out of 9 positive studies and correctly negative in 4 out of 9 negative studies. 4 out of 5 of the falsely negative studies were in patients who had taken antibiotics for over 7 days. We found that 99mTc Infecton gave better imaging results than radiolabelled leucocytes. Comparison between 99mTc Infecton and leucocyte imaging gave sensitivities of 84% and 81%, and specificities of 96% and 77%, respectively. INTERPRETATION: We believe that the specificity 99mTc Infecton confers for bacterial infection and its ease of administration are the main advantages of this new agent.

Adolescent↗
PubMed1996

Inter-observer agreement in the reporting of 99Tcm-DMSA renal studies.

The early identification of renal cortical scarring secondary to urinary reflux and/or renal infection is important in the management of patients with recurrent disease. Scintigraphic imaging of the renal cortex using 99Tcm-dimercaptosuccinic acid (DMSA) is often considered the standard method for the diagnosis of renal scars in both adults and children. Consistent reporting of 99Tcm-DMSA is nevertheless essential in ensuring that the clinician can act on the data reported. In this study, seven experienced observers were asked to report, independently, 99Tcm-DMSA data sets from 32 patients. The observers were asked to note the presence of a space occupying lesion or of a renal cortical scar(s) and to conclude if the kidney was normal or abnormal. There was marked variation in the number of renal cortical scars reported, the total number of scars seen and whether or not the kidney was normal or abnormal. After peer review of all data, consensus and referenced criteria were arrived at for a reanalysis of data. All scans were reread by the observers. There was some improvement in the concordant reporting of kidneys with renal scars (51 vs 61%) and whether or not the kidney was normal or abnormal (53 vs 63%). However, this was not statistically significant (at a level of P < 0.05). This study demonstrated significant inter-observer variation regarding the reporting of 99Tcm-DMSA studies. A consensus with agreed guidelines for data interpretation did not significantly affect this apparent lack of consistency of reporting.

Adolescent↗
PubMed1996

Gallium-67 imaging of pericardial lymphoma in AIDS.

A 33-yr-old homosexual man with acquired immune deficiency syndrome (AIDS) and Mycobacterium avium intracellulare (MAI) infection presented with fever, sweats, lethargy and dyspnea. A chest radiograph showed cardiomegaly and an echocardiograph revealed a large pericardial effusion. After pericardial aspiration, which confirmed T cell non-Hodgkin's lymphoma, he remained dyspneic. Gallium-67 imaging was performed to determine whether the patient's residual dyspnea was related to pulmonary MAI infection or lymphomatous infiltration of the heart. Planar 67Ga scintigraphy revealed intense tracer uptake in two areas within the mediastinum and surrounding the entire heart shadow but no evidence of pulmonary MAI infection. SPECT 67Ga scintigraphy precisely localized the two mediastinal abnormalities and demonstrated the tracer uptake around the heart to be pericardial rather than myocardial. Gallium-67 scintigraphy suggested that pericardial lymphoma was the likely basis of the patient's dyspnea.

AIDS-Related Opportunistic Infections↗
PubMed1995

Immunoscintigraphy with a 99Tcm-labelled anti-granulocyte monoclonal antibody in patients with human immunodeficiency virus infection and AIDS.

The value of immunoscintigraphy with technetium-99m (99Tcm) labelled anti-granulocyte monoclonal antibody (BW250/183) was studied prospectively in human immunodeficiency virus (HIV-1) antibody-positive patients presenting with fever without localizing symptoms or signs. Twenty-three studies were performed in 23 patients and the results of 99Tcm-anti-granulocyte imaging were compared with the definitive microbiological or cytological diagnosis. Twenty-one patients had an infective cause of pyrexia, one patient had disseminated lymphoma and one Kaposi sarcoma. 99Tcm-anti-granulocyte antibody imaging correctly identified the sites of infection in only five (24%) patients, four of whom had infective colitis (one also had bacterial pneumonia) and one of whom had cellulitis. Sixteen foci of infection were not localized by 99Tcm-anti-granulocyte immunoscintigraphy (false-negative scans). Six of these patients had Pneumocystis carinii pneumonia; other diagnoses in this group included bacterial or fungal pneumonia and bacteraemia secondary to line infections. 99Tcm-anti-granulocyte antibody did not accumulate in the patients with disseminated lymphoma and Kaposi sarcoma (true-negative scans). 99Tcm-anti-granulocyte imaging, therefore, appears useful in identifying extrathoracic infection in HIV-1 positive patients. Its lack of sensitivity for the identification of pulmonary infection means that its role in the investigation of HIV-1 antibody-positive patients with fever without localizing symptoms or signs is limited.

AIDS-Related Opportunistic Infections↗
PubMed1995

Khat chewing delays gastric emptying of a semi-solid meal.

BACKGROUND: The leaves of Khat are chewed for their central stimulant effect, but their use may cause anorexia and constipation. METHODS: Gastric emptying of a radio-labelled semi-solid meal was measured in 12 healthy volunteers on two occasions a week apart. Subjects chewed either Khat leaves (Catha edulis) or lettuce for 2 h before the study. RESULTS: Gastric emptying was significantly (P < 0.02) prolonged after chewing Khat compared with lettuce. CONCLUSION: The sympathomimetic action of cathinone in Khat may cause the observed delay in gastric emptying.

Adult↗
PubMed1994

A prospective study comparing SPET with MRI and CT as prognostic indicators following severe closed head injury.

Ten patients were studied prospectively afer severe closed head injury to determine the relationship between long-term clinical outcome and abnormalities detected by single photon emission tomography (99Tcm-HMPAO SPET), CT and MRI obtained within 60 days of injury. The ability of SPET to detect abnormalities not visualized by CT or MRI after cerebral trauma by the results of this study. Changes detected by SPET [global cerebral blood flow (gCBF) and number of regional cerebral blood flow (rCBF) deficits] soon after trauma were shown to be more closely correlated with long-term outcome than changes detected by MRI or CT. Templates were used to classify lesions by site and a multivariate analysis was undertaken to establish the importance of defect position in predicting clinical outcome. The results suggest that lesions in the temporal lobes, frontal lobes and basal ganglia are related to poor prognosis, and that SPET yields more useful prognostic data than the other methods.

Adult↗