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[Degenerative cerebellar diseases and differential diagnoses].
Reith, W, Roumia, S, Dietrich, P
Der Radiologe. 2016;(11):976-982
Abstract
CLINICAL/METHODICAL ISSUE Cerebellar syndromes result in distinct clinical symptoms, such as ataxia, dysarthria, dysmetria, intention tremor and eye movement disorders. STANDARD RADIOLOGICAL METHODS In addition to the medical history and clinical examination, imaging is particularly important to differentiate other diseases, such as hydrocephalus and multi-infarct dementia from degenerative cerebellar diseases. Degenerative diseases with cerebellar involvement include Parkinson's disease, multiple system atrophy as well as other diseases including spinocerebellar ataxia. ACHIEVEMENTS In addition to magnetic resonance imaging (MRI), nuclear medicine imaging investigations are also helpful for the differentiation. PRACTICAL RECOMMENDATIONS Axial fluid-attenuated inversion recovery (FLAIR) and T2-weighted sequences can sometimes show a signal increase in the pons as a sign of degeneration of pontine neurons and transverse fibers in the basilar part of the pons. The imaging is particularly necessary to exclude other diseases, such as normal pressure hydrocephalus (NPH), multi-infarct dementia and cerebellar lesions.
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2.
Role of isotope scan, including positron emission tomography/computed tomography, in nodular goitre.
Giovanella, L, Ceriani, L, Treglia, G
Best practice & research. Clinical endocrinology & metabolism. 2014;(4):507-18
Abstract
Nuclear medicine techniques were first used in clinical practice for diagnosing and treating thyroid diseases in the 1950s, and are still an integral part of thyroid nodules work-up. Thyroid imaging with iodine or iodine-analogue isotopes is the only examination able to prove the presence of autonomously functioning thyroid tissue, which excludes malignancy with a high probability. In addition, a thyroid scan with technetium-99m-methoxyisobutylisonitrile is able to avoid unnecessary surgical procedures for cytologically inconclusive thyroid nodules, as confirmed by meta-analysis and cost-effectiveness studies. Finally, positron emission tomography alone, and positron emission tomography combined with computed tomography scans with (18)F-fluoro-2-deoxy-d-glucose are also promising for diagnosing thyroid diseases, but further studies are needed before introducing them to clinical practice.
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3.
Iodine-131 SPET/CT and 18F-FDG PET/CT for the identification and localization of mediastinal lymph node metastases from differentiated thyroid carcinoma.
Xu, YH, Shen, CT, Xue, YL, Qiu, ZL, Luo, QY
Hellenic journal of nuclear medicine. 2013;(3):199-203
Abstract
Mediastinal lymph node metastases (MLNM) from differentiated thyroid carcinoma (DTC) are considered difficult to diagnose. The aim of this study was to assess the value of iodine-131 (131I) single photon emission tomography/computed tomography (SPET/CT) and of 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) for the diagnosis of MLNM from DTC. Five hundred and eleven consecutive patients operated for DTC and treated with 131I for ablation of the remnant thyroid and/or for treatment of metastases were enrolled in the study and underwent an 131I whole body scan (131I-WBS). Thirty seven sites of increased 131I uptake, on the 131I-WBS that could be an indication for MLNM were re-evaluated by a 131I-SPET/CT scan. Thirty four other patients with negative 131I-WBS but having elevated serum thyroglobulin (Tg), were examined by 18F-FDG PET/CT to possibly diagnose MLNM. A total of 44 DTC patients with MLNM were identified, among the above 37 and 34 cases: 25/37 (67.6%) cases were examined and identified by 131I-SPET/CT and 19/34 (55.9%) cases by 18F-FDG PET/CT. A total of 25 and 19 cases were identified. The male-to-female ratio and the average age in patients with 18F-FDG-avid MLNM were significantly higher than in patients with 131I-avid MLNM. Among the above 44 patients, 40 patients had superior mediastinal nodal metastases, 9 had aortic nodal metastases and only 1 inferior mediastinal nodal metastases. A patient could have metastases in more than one site. In conclusion, our study suggests that in 511 operated DTC patients, treated for remnant ablation and/or for metastases and examined by 131I-WBS, there were 37 cases doubtful of having MLNM in the 131I-WBS and 34 cases doubtful, because of negative 131I-WBS and elevated Tg. The 131I-SPET/CT scan was sensitive for detecting MLNM in 25 of the 37 cases and the 18F-FDG PET/CT in 19 of the 34 cases. These hybrid imaging modalities, when applied as above, were suitable for detecting more MLNM and thus, better supporting treatment planning in these DTC patients.
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4.
Glucagon-like peptide-1 receptor imaging for the localisation of insulinomas: a prospective multicentre imaging study.
Christ, E, Wild, D, Ederer, S, Béhé, M, Nicolas, G, Caplin, ME, Brändle, M, Clerici, T, Fischli, S, Stettler, C, et al
The lancet. Diabetes & endocrinology. 2013;(2):115-22
Abstract
BACKGROUND Small benign insulinomas are hard to localise, leading to difficulties in planning of surgical interventions. We aimed to prospectively assess the insulinoma detection rate of single-photon emission CT in combination with CT (SPECT/CT) with a glucagon-like peptide-1 receptor avid radiotracer, and compare detection rates with conventional CT/MRI techniques. METHODS In our prospective imaging study, we enrolled adults aged 25-81 years at centres in Germany, Switzerland, and the UK. Eligible patients had proven clinical and biochemical endogenous hyperinsulinaemic hypoglycaemia and no evidence for metastatic disease on conventional imaging. CT/MRI imaging was done at referring centres according to standard protocols. At three tertiary nuclear medicine centres, we used whole body planar images and SPECT/CT of the abdomen up to 168 h after injection of (111)In-[Lys40(Ahx-DTPA-(111)In)NH2]-exendin-4 ((111)In-DTPA-exendin-4) to identify insulinomas. Consenting patients underwent surgery and imaging findings were confirmed histologically. FINDINGS Between Oct 1, 2008, and Dec 31, 2011, we recruited 30 patients. All patients underwent (111)In-DTPA-exendin-4 imaging, 25 patients underwent surgery (with histological analysis), and 27 patients were assessed with CT/MRI. (111)In-DTPA-exendin-4 SPECT/CT correctly detected 19 insulinomas and four additional positive lesions (two islet-cell hyperplasia and two uncharacterised lesions) resulting in a positive predictive value of 83% (95% CI 62-94). One true negative (islet-cell hyperplasia) and one false negative (malignant insulinoma) result was identified in separate patients by (111)In-DTPA-exendin-4 SPECT/CT. Seven patients (23%) were referred to surgery on the basis of (111)In-DTPA-exendin-4 imaging alone. For 23 assessable patients, (111)In-DTPA-exendin-4 SPECT/CT had a higher sensitivity (95% [95% CI 74-100]) than did CT/MRI (47% [27-68]; p=0.011). INTERPRETATION (111)In-DTPA-exendin-4 SPECT/CT could provide a good second-line imaging strategy for patients with negative results on initial imaging with CT/MRI. FUNDING Oncosuisse, the Swiss National Science Foundation, and UK Department of Health.
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5.
Analysis of bone formation on porous and calcium phosphate-coated acetabular cups: a randomised clinical [18F]fluoride PET study.
Ullmark, G, Sörensen, J, Nilsson, O
Hip international : the journal of clinical and experimental research on hip pathology and therapy. 2012;(2):172-8
Abstract
We present a study using Fluoride-Positron Emission Tomography (F-PET/CT) to analyse new bone formation in periacetabular bone adjacent to press fit cups following THA. In 16 THA (8 patients) with bilateral hip osteoarthritis simultaneous bilateral total hip arthroplasty (THA) was performed, employing electrochemically applied calcium phosphate coated (HA) cups or porous-coated (PC) cups allocated at random to compare the two sides. A reference group of 13 individuals with a normal healthy hip was used to determine 'normal' bone metabolism. [18F]fluoride -PET/CT was used to analyze bone formation adjacent to the cups 1 week, 4 months and 12 months after surgery. Clinical and radiographic evaluation was performed preoperatively, postoperatively and at 2 years. Bone forming activity had a mean of 5.71, 4.69 and 3.47 SUV around the HA- and 5.04, 4.80 and 3.50 SUV around the PC-cups at 1 week, 4 months and 12 months respectively. Normal bone metabolism was 3.68 SUV. After 1 year activity had declined to normal levels for both groups. The clinical results were good in all cases. HA coating resulted in higher uptake indicating higher bone forming activity after 1 week. F-PET/CT is a valuable tool to analyse bone formation and secondary stabilisation of an acetabular cup.
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6.
PET/CT imaging in systemic lupus erythematosus.
Curiel, R, Akin, EA, Beaulieu, G, DePalma, L, Hashefi, M
Annals of the New York Academy of Sciences. 2011;:71-80
Abstract
Systemic lupus erythematosus (SLE) is the classical immune-complex disease. Involvement of vital organs, particularly the kidneys and brain, accounts for significant morbidity and mortality. A number of imaging tools are currently available for evaluation of inflammatory conditions. By targeting the increased glucose uptake of infiltrating granulocytes and tissue macrophages, positron emission tomography with fluorine-18 fluorodeoxyglucose ([(18) F]FDG PET/CT) has been shown to delineate inflammation with high sensitivity. Because activated lymphocytes have increased glucose metabolism, [(18) F]FDG PET has been successfully used to visualize large concentrations of these cells in lymphoid organs where antigen presentation and lymphocyte activation occur. Widespread increased FDG uptake in lymph nodes of patients with active SLE, as well as increased thymic uptake, has been described. The most prevalent and dramatic PET/CT finding in neuropsychiatric SLE (NP-SLE) patients is parieto-occipital hypometabolism. In conclusion, PET/CT has become an excellent ancillary tool to assess disease activity and prognosis in SLE patients.
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7.
Molecular imaging in thyroid cancer.
Heston, TF, Wahl, RL
Cancer imaging : the official publication of the International Cancer Imaging Society. 2010;(1):1-7
Abstract
Molecular imaging plays an important role in the evaluation and management of thyroid cancer. The routine use of thyroid scanning in all thyroid nodules is no longer recommended by many authorities. In the initial work-up of a thyroid nodule, radioiodine imaging can be particularly helpful when the thyroid stimulating hormone level is low and an autonomously functioning nodule is suspected. Radioiodine imaging can also be helpful in the 10-15% of cases for which fine-needle aspiration biopsy is indeterminate. Therapy of confirmed thyroid cancer frequently involves administration of iodine-131 after surgery to ablate remnant tissue. In the follow-up of thyroid cancer patients, increased thyroglobulin levels will often prompt the empiric administration of 131I followed by whole body radioiodine imaging in the search for recurrent or metastatic disease. 131I imaging of the whole body and blood pharmacokinetics can be used to determine if higher doses of 131I can be given in thyroid cancer. The utility of [18F]fluorodeoxyglucose (FDG) positron emission tomography (PET) is steadily increasing. FDG is primarily taken up by dedifferentiated thyroid cancer cells, which are poorly iodine avid. Thus, it is particularly helpful in the patient with an increased thyroglobulin but negative radioiodine scan. FDG PET is also useful in the patient with a neck mass but unknown primary, in patients with aggressive (dedifferentiated) thyroid cancer, and in patients with differentiated cancer where histologic transformation to dedifferentiation is suspected. In rarer types of thyroid cancer, such as medullary thyroid cancer, FDG and other tracers such as 99mTc sestamibi, [11C]methionine, [111In]octreotide, and [68Ga]somatostatin receptor binding reagents have been utilized. 124I is not widely available, but has been used for PET imaging of thyroid cancer and will likely see broader applicability due to the advantages of PET methodology.
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8.
Role of 18F-DOPA PET/CT imaging in congenital hyperinsulinism.
Ismail, D, Hussain, K
Reviews in endocrine & metabolic disorders. 2010;(3):165-9
Abstract
Congenital hyperinsulinism is a leading cause of severe hypoglycaemia in the newborn period. There are two (diffuse and focal) histological subtypes of congenital hyperinsulinism. The diffuse form affects the entire pancreas and if medically unresponsive will require a near total (95%-98%) pancreatectomy. The focal form affects only a small region of the pancreas (with the rest of the pancreas being normal in endocrine and exocrine function) and only requires a limited pancreatectomy. This limited section of the focal lesion has the potential for curing the patient. Thus the pre-operative differentiation of these two subgroups is extremely important. Recent advances in Fluorine-18-L-dihydroxyphenylalanine positron emission tomography ((18)F-DOPA PET/CT) have radically changed the clinical approach to patient with congenital hyperinsulinism. In most patients this novel imaging technique is able to offer precise pre-operative localisation of the focal lesion, thus guiding the extent of surgical resection.
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9.
Prognosis and reevaluation of lung cancer by positron emission tomography imaging.
Erasmus, JJ, Rohren, E, Swisher, SG
Proceedings of the American Thoracic Society. 2009;(2):171-9
Abstract
Positron emission tomography (PET) imaging using (18)F-2-deoxy-D-glucose, a D-glucose analog labeled with fluorine-18 (FDG-PET), is being evaluated in the assessment of prognosis and therapeutic response in patients with non-small cell lung cancer. FDG-PET imaging has the potential to allow more appropriate selection of patients for surgical resection and for neoadjuvant and aduvant chemotherapy as well as chemoradiation. Currently, the absence of standardization in how FDG-PET images are obtained and interpreted limits its widespread clinical utility. Although prospective multi-institutional trials and standardization of FDG-PET imaging protocols are required for the true utility to be determined, the evolving experience with FDG-PET imaging indicates a greater and integral role in treatment decisions. This article will discuss the assessment of prognosis and treatment response in patients with non-small cell lung cancer using FDG-PET, and will emphasize potential advantages and limitations in clinical management.
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10.
Imaging of gynecologic malignancies with FDG PET-CT: case examples, physiologic activity, and pitfalls.
De Gaetano, AM, Calcagni, ML, Rufini, V, Valentini, AL, Gui, B, Giordano, A, Bonomo, L
Abdominal imaging. 2009;(6):696-711
Abstract
The utilization of 2-[fluorine 18] fluoro-2-deoxy-D-glucose (FDG) positron emission tomography (PET) in combination with computed tomography (CT) in the assessment of gynecologic malignancies has been rapidly growing in recent years; however, its role in clinical practice has yet to be established. A number of pitfalls are commonly encountered, including normal physiologic activity in bowel loops and blood vessels, or focal retained activity in ureters and urinary bladder. Increased uptake has also been reported in many benign pelvic processes and in premenopausal patients; endometrial activity changes cyclically, whereas increased ovarian uptake may be functional. FDG PET-CT has an emerging role in staging nodal disease and in the evaluation of local recurrence or peritoneal spread of gynecologic malignancies and is also useful in monitoring response to therapy and in long-term follow-up. FDG PET-CT is most suitable in patients with high tumor markers and negative or uncertain conventional imaging data. Patient preparation, proper scanning protocol, combined assessment of PET and CT data, and the evaluation of conventional imaging findings are essential to define disease and to avoid diagnostic pitfalls.