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T Nunan

Publications and source records attributed to T Nunan.

14 recordsLinked to original sources
PubMed2005

Prognostic value of interim FDG-PET after two or three cycles of chemotherapy in Hodgkin lymphoma.

BACKGROUND: Long-term survival from Hodgkin lymphoma (HL) is 80-90%, but the treatment has serious late adverse effects. Modern risk-adapted treatment requires accurate assessment of the patient's prognosis. This investigation assessed the value of positron emission tomography (PET) with 2-[18F]fluoro-2-deoxy-D-glucose (FDG-PET) after two or three cycles of chemotherapy for prediction of progression-free survival (PFS) and overall survival (OS). PATIENTS AND METHODS: A total of 85 patients with HL underwent FDG-PET after two or three cycles of chemotherapy. Median follow-up was 3.3 years. FDG-PET results were related to PFS and OS using Kaplan-Meier analysis. Regression analyses were employed to test for independence of established pretreatment prognostic factors. RESULTS: After two or three cycles of chemotherapy, 63 patients had negative FDG-PET scans, nine patients had minimal residual uptake (MRU) and 13 patients had positive scans. Three PET-negative patients and one patient from the MRU group relapsed. In the PET-positive group, nine patients progressed and two died. Survival analyses showed highly significant associations between early interim FDG-PET and PFS (P <0.0001) and OS (P <0.03). All advanced-stage patients with positive interim FDG-PET relapsed within 2 years. CONCLUSION: Early interim FDG-PET is an accurate and independent predictor of PFS and OS in HL. A positive interim FDG-PET is highly predictive of relapse in advanced-stage disease.

Adolescent↗
PubMed2005

Misinterpretation of radioisotope imaging in pelvic kidneys.

We report the case of a gentleman referred with apparent worsening function in a hydronephrotic left-sided pelvic kidney. Imaging with Tc-99m-Mercaptoacetyltriglycine (MAG 3) in 1999, showed that the left kidney contributed 46% of renal function with no evidence of obstruction. Three years later, repeat scanning showed ectopic kidney function had decreased to 20% and with worsening pain, nephrectomy had been suggested. Review of the second MAG 3 scan revealed that only posterior images had been obtained. With pelvic kidneys, the pelvis forms a barrier between the radioactively labelled tracer and the gamma camera, thus, reducing the amount of radiation detected and underestimating function. A subsequent Dimercaptosuccinic acid scan (DMSA) was carried out with posterior and anterior images, the latter showing split renal function was identical to that seen on the initial scan. In patients with pelvic kidneys, anterior views must be obtained during radionuclide scanning if unnecessary nephrectomy is to be avoided.

False Positive Reactions↗
PubMed2003

Nuclear medicine and radionuclide imaging: a survey of recruitment issues in the United Kingdom.

This wide ranging survey has highlighted difficulties in recruiting trained and committed individuals into nuclear medicine and radionuclide radiology. Several key factors have been recognised that reduce the attractiveness of the training. Recommendations include the rotation of medical senior house officers through nuclear medicine, reconsideration of dual accreditation in nuclear medicine and medicine, an increase in the number of consultant posts in nuclear medicine, parity of remuneration for nuclear medicine trainees and finally, an appropriate sessional provision for those providing radionuclide radiology services.

Education↗
PubMed2002

Value of isotope lymphography in the diagnosis of lymphoedema of the leg.

BACKGROUND: Isotope lymphography has largely replaced contrast lymphography in the diagnosis of lymphoedema. Its accuracy has only been assessed in small studies and it is not known if it can identify patients with a proximal lymphatic obstruction who may be suitable for lymphatic bypass surgery. METHODS: Three hundred and ninety-five patients suspected to have lymphoedema were investigated by isotope lymphography between 1985 and 1995. Contrast lymphography was also carried out in 29 of these patients because the isotope results were thought to be misleading, or because lymphatic bypass surgery was being considered. RESULTS: In the 29 patients who had both investigations isotope lymphography detected 20 of 24 abnormal lymphatic systems. Four legs with obstructed groin lymphatics were reported as normal. Two legs with normal contrast lymphograms were erroneously diagnosed as having lymphoedema in the isotope study. Detectable groin nodes on the scintigrams were indicative of either normal lymphatics or proximal lymphatic obstruction. An increase in isotope uptake over 30-60 min of less than 50 per cent, or a total absence of isotope within groin nodes, was a sensitive indicator that patients were unsuitable for lymphatic bypass surgery. CONCLUSION: Isotope lymphography is a moderately sensitive test for lymphoedema, which will mistakenly classify some normal legs as lymphoedematous. It will usually correctly identify patients who are suitable for lymphatic bypass surgery.

Contrast Media↗
PubMed2001

Comparison of positron emission tomography scanning and sentinel node biopsy in the detection of micrometastases of primary cutaneous malignant melanoma.

PURPOSE: Sentinel node biopsy (SNB) is a surgical technique for detecting micrometastatic disease in the regional draining nodes. 2-fluorine-18-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) scanning is an imaging technique that can detect clinically undetectable metastases. This prospective study was undertaken to compare the sensitivity of FDG-PET scanning with SNB in the detection of micromatastatic malignant melanoma. PATIENTS AND METHODS: Fifty consecutive patients (23 women, 27 men; mean age, 53 years) with primary melanoma >1 mm thick or lymphatic invasion were recruited (mean, 2.41 mm). Primary lesions had been narrowly excised (<1 cm). Patients underwent PET scanning followed by SNB, using a dual technique. Preoperative lymphoscintigraphy was used to identify the draining basin. Lymph nodes were examined histologically and immunostained for S100 and HMB 45. RESULTS: The sentinel node (SN) was identified in all patients. Fourteen patients (28%) had positive SNBs, including eight patients with melanoma <1.5 mm thick. In none of these 14 patients did PET scans identify metastatic disease in the SN or draining basin. In seven patients, the PET scans were positive in other locations, and in four cases, this was suspicious of metastatic disease. However, no patient has developed recurrent melanoma (mean follow-up, 15 months). All patients with positive SNBs underwent therapeutic lymph node dissection. Further lymph node involvement was found in two patients (primary lesions, 1.3 mm and 3.5 mm thick). CONCLUSION: This study demonstrates the limitations of FDG-PET scanning in staging patients with primary melanoma. SNB is the only reliable method for identifying micrometastatic disease in the regional draining node.

Adult↗
PubMed2001

Chromium-51 ethylenediamine tetraacetic acid glomerular filtration rate: a better predictor than glomerular filtration rate calculated by the Cockcroft-Gault formula for renal involvement in systemic lupus erythematosus patients.

OBJECTIVE: To investigate whether the ethylenediamine tetraacetic acid (EDTA) glomerular filtration rate (GFR) is a better indicator of the degree of renal involvement than serum creatinine concentration or creatinine clearance calculated by the Cockroft-Gault formula. METHODS: We studied prospectively all systemic lupus erythematosus (SLE) patients with normal or borderline serum creatinine concentration (<110 micromol/l) and urinary sediment abnormalities and/or proteinuria in the last 2 yr. EDTA-GFR, serum creatinine concentration, calculated creatinine clearance (Cockroft-Gault formula) and 24-h urine protein were determined at the same time. Renal biopsies were performed in patients with low values of EDTA-GFR or significant proteinuria. RESULTS: Twenty-three patients were identified, of whom 22 were females. The average age of the patients was 31.6+/-8.2 yr. Biopsies were assigned to WHO classes as follows: class II, 1 patient; class III, 6 patients; class IV, 10 patients; class V, 6 patients. The average serum creatinine concentration, EDTA-GFR and calculated creatinine clearance were 79.8+/-mol/l, 74.5 ml/min and 97 ml/min respectively. EDTA-GFR showed abnormal values (<80 ml/min) in 15 of the 23 patients (65.2%) while calculated creatinine clearance was abnormal (<80 ml/min) in three of the 23 patients (13%) (P<0.001). Using the Pearson correlation test, we did not find any correlation between EDTA-GFR or creatinine clearance values and the sum of activity and chronicity indices. CONCLUSION: GFR performed by EDTA-GFR correctly predicted renal involvement in SLE patients, whereas GFR calculated by the Cockcroft-Gault formula may have underestimated renal function. Significant numbers of patients with WHO class III, IV or V lupus nephritis may be missed if biochemical creatinine clearance or serum creatinine concentration alone is used to assess renal disease.

Adolescent↗
PubMed1997

The development of regional nuclear medicine audit in south Thames.

A programme of audit, including clinical audit, organizational audit and patient/clinician satisfaction surveys, has been implemented in nuclear medicine departments throughout the South Thames Regional Health Authority (RHA). The clinical topics which have been audited include. ventilation-perfusion lung imaging, bone imaging, liver imaging, thyroid imaging and renal static DMSA imaging. Guidelines have been set for nuclear medicine practice in each of these areas against which further audit can be performed. Organizational audits have been performed in 10 nuclear medicine departments in the South Thames RHA and a confidential report supplied to the head of each department, consisting of findings and recommendations. A programme of re-audit has also commenced. The main findings have been a lack of facilities and space. Patient satisfaction surveys have been implemented in nine departments and a high level of patient satisfaction has been demonstrated. A clinical satisfaction survey has been implemented in 13 departments. It is hoped to continue this successful programme of audit to improve nuclear medicine practice by closing audit loops.

England↗
PubMed1996

The use of low-dose intravenous insulin in clinical myocardial F-18 FDG PET scanning.

The effectiveness of low-dose intravenous insulin boluses to improve study quality in F-18 FDG myocardial scans is investigated. Seventeen patients were imaged using a protocol in which only diabetic patients with fasting blood glucose levels > 8 mmol/l were given insulin. Fifty-three patients were imaged using a protocol in which all patients were given 1-3 IU intravenously of insulin immediately before F-18 FDG injection, based on fasting blood glucose levels. Scan quality was rated as poor, good, or excellent. Using the conventional protocol, 29% of the scans were poor quality (uniterpretable), 47% were good, and 23% were excellent. Using the low-dose intravenous insulin boluses protocol; 2% were poor, 53% were good, and 45% were excellent (P = 0.01). There were no significant differences in the proportion of diabetic patients, age, or fasting blood glucose levels. Low-dose intravenous insulin bolus is an easy and safe method of improving myocardial F-18 FDG scan quality in nondiabetic and diabetic patients.

Deoxyglucose↗
PubMed1994

Whole-body 18F-fluorodeoxyglucose positron emission tomography in preoperative evaluation of lung cancer.

Despite use of computed tomography, some lung cancer patients are found to have unresectable disease at surgery, or they present early with metastases. We studied whether whole-body positron emission tomography (PET) with 18F-fluorodeoxyglucose (18FDG) would improve the preoperative detection of metastases. We retrospectively analysed 34 patients with "operable" non-small-cell lung cancer who underwent 18FDG PET after routine assessment. Management changes produced by the PET scan and confirmatory tests were reviewed. PET identified unsuspected malignant lesions in 10 (29%) patients. Management changes occurred in 14 (41%), including 6 (18%) patients who were changed to non-surgical therapy. These data suggest that whole-body 18FDG PET improves preoperative assessment of lung cancer patients.

Aged↗
PubMed1991

Why clinical PET?

Explore the source record for details and available documents.

Brain Diseases↗
PubMed1990

Haemophilia, AIDS and lung epithelial permeability.

Lung 99mTc DTPA transfer was measured in HIV antibody-positive haemophiliacs (11 smokers, 26 nonsmokers, 5 patients with Pneumocystis carinii pneumonia (PCP]. Lung 99mTc DTPA transfer as a marker of lung epithelial permeability was measured as the half time of transfer (from airspace into blood). This half time was faster in smokers compared to nonsmokers and the transfer curve was monoexponential. In nonsmokers no difference was observed between asymptomatic HIV-positive haemophiliacs and normal subjects, with the exception of the lung bases. At the lung bases in HIV-positive haemophiliac nonsmokers the transfer was faster than in normal individuals, implying increased alveolar permeability. Pneumocystis carinii pneumonia resulted in a rapid transfer of 99mTc DTPA (mean T50 of 2 minutes) and the transfer curve was biphasic, confirming previous observations in homosexual HIV antibody-positive patients with PCP. These changes returned to a monoexponential profile by 6 weeks following successful treatment. The DTPA lung transfer study may enable clinicians to instigate therapy for PCP without the need for initial bronchoscopy and provide a noninvasive method for the reassessment of patients should further respiratory signs or symptoms develop. This method is considered to be highly cost-effective in that it obviates the use of factor VIII concentrates required to cover bronchoscopic procedures and, with its early application and ease of use as a follow-up investigation, permits the evaluation of patients on an outpatient basis, thus reducing hospital costs.

Acquired Immunodeficiency Syndrome↗
PubMed1990

Pulmonary deposition of nebulised pentamidine isethionate: effect of nebuliser type, dose, and volume of fill.

An estimate of the absolute pulmonary deposition of nebulised pentamidine isethionate was obtained in nine patients with AIDS. Two nebuliser systems were compared, System 22 Mizer (Medic-Aid) and Respirgard II (Marquest), with 50 and 150 mg doses of pentamidine in a 3 ml solution driven by an air flow of 6 l/min with the patient in the sitting position. The 50 mg pentamidine dose was repeated with a 6 ml fill with both devices. The nebuliser cloud was labelled with technetium-99m human serum albumin (Ventocol) and lung deposition was measured with a gamma camera. Of the two nebulisers studied, System 22 Mizer delivered more drug to the lungs as a whole and to each individual lung region, including the peripheral and upper zones. For the 50 mg dose the mean (SEM) total pulmonary deposition with the 3 and the 6 ml fill respectively was 2.63 (0.34) and 3.71 (0.41) mg for the System 22 Mizer and 1.37 (0.26) and 1.45 (0.18) mg for the Respirgard II. For the 150 mg dose the System 22 Mizer delivered 7.16 (1.02) mg and the Respirgard II 4.34 (0.57) mg. Increasing the volume of fill from 3 to 6 ml increased pulmonary deposition with System 22 Mizer, and this was related to an increase in nebuliser output. Neither pulmonary deposition nor nebuliser output was increased by using a 6 ml solution in the Respirgard II. Increasing the volume of fill prolonged the time required for nebulisation with both nebulisers. The System 22 Mizer produced more nonpulmonary (gastric and oropharyngeal) deposition of drug, more frequent local adverse effects (cough, burning in the throat, and a metallic taste), and small reductions in lung function, particularly with the 150 mg pentamidine dose. Thus nebuliser type, volume of fill, and nebuliser dose affect the pulmonary deposition of pentamidine. A 300 mg dose of pentamidine via a Respirgard II is generally recommended as providing effective prophylaxis; our results suggest that similar pulmonary deposition can be produced with System 22 Mizer and 150 mg pentamidine. A clinical trial would be needed to show whether this regimen provides similar prophylactic benefit.

Acquired Immunodeficiency Syndrome↗
PubMed1990

Endocytosis of cationized horseradish peroxidase by glomerular epithelial cells is reduced in puromycin glomerulopathy.

Rats were treated with a single intravenous injection of aminonucleoside of puromycin and were sacrificed between 1 and 21 days after injection. The conjugate of horseradish peroxidase with a poly-L-lysine (HRP.PL) was used to reveal endocytotic activity in glomerular epithelial cells (GEC). This conjugate was injected intravenously 2 h before each sacrifice. Renal tissue was taken and treated cytochemically with a conventional DAB technique and observed by light and electron microscopy. The assessment of endocytosis by glomerular epithelial cells was performed on 1-micron sections by counting HRP.PL grains in the GEC and expressing this in terms of the area of glomerulus examined. The results were compared to those found in normal rats. Our results show that GEC endocytotic function was reduced during the whole period of the experiment. It fell quickly from 1 day after puromycin injection and reached the most marked reduction on the 4th day, preceding the peak of proteinuria which was between 7 and 12 days. From the 5th day onward the endocytotic function gradually recovered, but was still abnormal at the end of the experiment.

Animals↗