Nuclear Medicine Physicians (nuclear + medicine_physician)

Distribution by Scientific Domains


Selected Abstracts


Accuracy and definitive interpretation of preoperative technetium 99m sestamibi imaging based on the discipline of the reader,

HEAD & NECK: JOURNAL FOR THE SCIENCES & SPECIALTIES OF THE HEAD AND NECK, Issue 5 2009
Ayesha N. Khalid MD
Abstract Background. Technetium 99m sestamibi scans have become a principal means of localizing parathyroid adenomas. Its accuracy and reliability has allowed for the proliferation of minimal access parathyroidectomy. Localizing interpretation of these scans often drives referral of hyperparathyroid patients for surgery. Interpretation of these scans may differ between nuclear medicine physicians and surgeons. Methods. We reviewed patients (N = 65) with digital images from an academic medical center with the diagnosis of primary hyperparathyroidism. We assessed the willingness to define an adenoma's location, the interrater reliability, and the accuracy of technetium (Tc-99m) sestamibi read by a surgeon and a nuclear medicine physician. Results. There was poor correlation between both readers for assessment of quality of images (k = 0.54, 0.07) but very good correlation for adenoma location (k = 0.81). Conclusion. Both readers had good accuracy in predicting the location of the parathyroid adenoma. The surgeon was more likely to call a scan positive. © 2008 Wiley Periodicals, Inc. Head Neck, 2009 [source]


Lessons from a review of thyroglobulin assays in the management of thyroid cancer

INTERNAL MEDICINE JOURNAL, Issue 6a 2008
J. Wong
Abstract Thyroglobulin (Tg) measurement has become increasingly an important and integral part of the follow up and management of patients with differentiated thyroid cancer. Clinicians predominantly rely on Tg for decision-making for surveillance of patients with differentiated thyroid cancer, but despite this new reliance, issues regarding Tg measurement have not been appropriately addressed especially within a local context. In the process of developing an institutional protocol we have identified that there are significant clinical and technical issues regarding Tg measurement, and surprisingly Tg assessment is currently not part of an external quality control programme. We conducted a small pilot study to specifically emphasize some of the assay issues. We aim to inform endocrinologists, pathologists and nuclear medicine physicians, the need and urgency for these issues to be addressed to improve the ongoing surveillance of differentiated thyroid cancer. [source]


Sentinel lymph node biopsy in patients with melanoma and breast cancer

INTERNAL MEDICINE JOURNAL, Issue 9 2001
R. F. Uren
Abstract Sentinel lymph node biopsy (SNLB) is a new method for staging regional node fields in patients with cancers that have a propensity to metastasise to lymph nodes. The majority of early experience has been obtained in patients with melanoma and breast cancer. The technique requires the close cooperation of nuclear medicine physicians, surgical oncologists and histopathologists to achieve the desired accuracy. It involves: (i) identification of all lymph nodes that directly drain a primary tumour site (the sentinel nodes) by the use of pre-operative lymphoscintigraphy, (ii) selective excision of these nodes by the surgeon, guided by pre-operative blue dye injection and a gamma detecting probe intra-operatively and (iii) careful histological examination of the sentinel nodes by the histopathologist using serial sections and immunohistochemical stains. If the nodes are normal it can be inferred with a high degree of accuracy that all nodes in the node field are normal. This means that radical dissections of draining node fields can be avoided in patients with normal lymph nodes. A further advantage of lyamphatic mapping is that drainage to sentinel nodes in unusual locations is identified, leading to more accurate nodal staging than could be achieved with routine dissection of the closest node field. (Intern Med J 2001; 31: 547,553) [source]


Development of a parathyroid database in Melbourne and review of the last 50 cases

ANZ JOURNAL OF SURGERY, Issue 9 2004
Meei J. Yeung
Background: Minimally invasive parathyroidectomy (MIP) is only possible if preoperative localization studies accurately identify the abnormal parathyroid tissue. The aim of the present paper was to evaluate the accuracy of these studies in our geographical region and the consequences on MIP. Methods: A Filemaker Pro database was designed and a retrospective analysis was carried out on the last 50 parathyroidectomies. Results: There were a total of 49 patients who underwent parathyroidectomy; with one patient having two operations. Forty-nine preoperative ultrasound localization studies were performed. Ultrasound sensitivity of correct localization of abnormal parathyroids was 41% with a false positive rate of 25%. Twenty-two sestamibi scans identified 14 abnormal parathyroids. Sestamibi scanning had a sensitivity of 32% for correct localization and a false positive rate of 32%. There were 16 different radiologists or nuclear medicine physicians involved with the nuclear medicine scans, and 22 different radiologists involved in the preoperative ultrasound scans. Forty-seven patients were cured of hyperparathyroidism after a primary operation, with a total of 48 patients in all being cured following re-exploration. One patient was lost to follow up. The success of primary exploration was therefore 96% and following re-exploration this increased to 98%. Conclusion: We found preoperative localization studies to have low sensitivities and high false positive rates. To move successfully towards MIP, we need to identify a radiologist with a special interest in localization studies to achieve greater accuracy. [source]


Is 18F-fluorodeoxyglucose positron emission tomography scanning a reliable way to assess disease activity in takayasu arteritis?

ARTHRITIS & RHEUMATISM, Issue 4 2009
Laurent Arnaud
Objective 18F-fluorodeoxyglucose,positron emission tomography (FDG-PET) scanning has been proposed as a new way of assessing disease activity in Takayasu arteritis (TA), but previous studies have used the nonvalidated National Institutes of Health (NIH) global activity criteria, and thus might be biased. This study was undertaken to determine the value of PET scanning for assessment of disease activity in TA, by comparing PET scan data with clinical, biologic, and magnetic resonance imaging (MRI) data assessed separately. Methods Twenty-eight patients with TA (according to the American College of Rheumatology criteria) underwent a total of 40 PET scans. Images were reviewed by 2 pairs of independent nuclear medicine physicians and assessed for pattern and intensity of vascular uptake. TA activity data were obtained within 15 days of the PET scans. Results PET scanning revealed abnormal vascular uptake in 47% of the 40 examinations. The uptake intensity grade was 0 in 7 scans, grade 1 in 7 scans, grade 2 in 13 scans, and grade 3 in 13 scans. Morphologic analysis was conducted by grading the pattern of the vascular uptake as diffuse (73%), segmental (20%), or focal (13%). There was a trend toward an association between clinically active disease and the semiquantitative assessment of FDG uptake (P = 0.08). We found no statistical association between levels of acute-phase reactants and intensity of uptake. There was no significant association between the semiquantitative assessment of FDG uptake and the presence of vascular wall thickening (P = 0.23), gadolinium uptake (P = 0.73), or the presence of vascular wall edema (P = 0.56). Conclusion Our findings indicate that there is no association between FDG vascular uptake intensity and clinical, biologic, or MRI assessment of disease activity. Previous studies using the nonvalidated NIH global activity criteria are likely biased. [source]


Variability of the administered radioiodine doses for the treatment of hyperthyroidism in Belgium

CLINICAL ENDOCRINOLOGY, Issue 2 2006
Marianne Tondeur
Summary Objective,, When using radioiodine for hyperthyroidism there is no consensus regarding the administration of fixed or calculated doses. Guidelines do not specify the preferable approach or the parameters to use to calculate the dose. Therefore, the dose might be quite different with regard to the chosen procedure. This study was undertaken to evaluate the variability of the amount of radioiodine administered in Belgium in various cases of hyperthyroidism. Design and patients, Twenty-one Belgian nuclear medicine physicians received summarized clinical files from 10 patients suffering from overt hyperthyroidism (n = 7) or subclinical hyperthyroidism (n = 3). Five patients had homogeneous goiters, one had multinodular goiter, and four had hot nodule. Participants had to determine the radioiodine dose (millicuries, mCi) they would give in each case. Results,, Proposed doses varied between 2 mCi and 25 mCi. Mean proposed dose for nodular disease was 10·71 mCi; it was 6·79 mCi for homogeneous goiter. For individual cases, a difference between the lowest and the highest dose of more than 17 mCi was observed in more than 50% of the cases. Conclusions,, We believe that more precise guidelines are mandatory, underlying uncertainties, controversies but recommending however, as minimal and maximal doses to administer, as well as clinical and biological parameters, if any, to be taken into account in order to modulate these doses. [source]