The quarterly journal of nuclear medicine : official publication of the Italian Association of Nuclear Medicine (AIMN) [and] the International Association of Radiopharmacology (IAR)
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(99m)Tc-MIBI radio-guided surgery results, obtained in a group of 141 patients with primary hyperparathyroidism (HPT), are reported. ⋯ It can be concluded that: (a) in primary HPT patients with high scan/ultrasound probability of solitary parathyroid adenoma and normal thyroid gland, the gamma probe appears to be an effective, rapid and safe technique to perform minimally invasive radio-guided surgery; b) a (99m)Tc-MIBI dose as low as 37 MBq appears to be adequate to successfully perform radio-guided surgery; c) the measurement of quick PTH is recommended during minimally invasive radio-guided surgery; d) minimally invasive radio-guided surgery can be performed also in HPT patients with previous parathyroid/thyroid surgery thus limiting surgical trauma; e) with the possible exception of parathyroid adenoma located in ectopic sites or deep in the neck, the gamma probe technique does not seem recommendable in HPT patients with concomitant nodular goiter.
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The diagnostic strategy for pulmonary embolism, based on the mismatch of the ventilation/perfusion scan, was developed some 30 years ago on the following assumption: since the disorder involves the pulmonary vessels, it was surmised that in the embolized regions lung alveoli are unperfused or poorly perfused but well ventilated. Hence, it was inferred that this disorder was characterized, unlike parenchymal disease, by ventilation/perfusion mismatch in the affected lung zones and by an obvious increase of wasted ventilation, i.e., dead space. As matter of fact, experimental evidence on the redistribution of ventilation away from the vascular occluded lung had been already obtained in the early 60s of the last century. ⋯ This may occur by different mechanisms in the various stages of APE: bronchoconstriction mediated by local hypocapnia, atelectasis (occasionally hemorrhagic) related to alteration of surfactant production, bronchiolar obstruction and pulmonary infarction ascribed to degenerative and/or necrotic changes secondary to insufficient blood flow. In dogs and humans alike, the dead space measured by MIGET does not increase and that obtained from CO2 increases far less than the amount of unperfused lung in APE thus confirming a substantial redistribution of ventilation away from the embolized lung zones. Taken together, all these observations provide the pathophysiological explanation of the unacceptedly low level of sensitivity for the diagnostic strategy of APE based on the mismatch of the ventilation/perfusion scan.
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Clinical assessment is a cornerstone of the recently validated diagnostic strategies for pulmonary embolism (PE). Although the diagnostic yield of individual symptoms, signs, and common laboratory tests is limited, the combination of these variables, either by empirical assessment or by a prediction rule, can be used to express a clinical probability of PE. The latter may serve as pretest probability to predict the probability of PE after further objective testing (posterior or post-test probability). ⋯ These results underscore the importance of incorporating the standardized reading of the electrocardiogram and of the chest radiograph into the clinical evaluation of patients with suspected PE. The interpretation of these laboratory data, however, requires experience. Future research is needed to develop standardized models, of varying degree of complexity, which may find application in different clinical settings to predict the probability of PE.
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Review Comparative Study
Evaluation of treatment response in patients with lymphoma using [18F]FDG-PET: differences between non-Hodgkin's lymphoma and Hodgkin's disease.
Fluorine-18fluorodeoxyglucose positron emission tomography ([18F]FDG-PET) has become a very useful technique for the therapy monitoring of patients with lymphoma. It provides unique information about the metabolic behavior of the disease independent of morphological criteria. In recent years, [18F]FDG-PET has proven to be a technique with high sensitivity for the detection of residual tumor. ⋯ However, most recent published studies included both HD and NHL, although [18F]FDG-PET scan results in Hodgkin's disease (HD) has a different impact than in Non Hodgkin's Lymphoma (NHL). In this paper, we summarize our findings on the role of [18F]FDG-PET in the therapy evaluation of lymphoma patients in a large group of patients and highlight the differences between the interpretations of the results of HD and NHL patients. Finally, a strategy for the implementation of [18F]FDG-PET in the management of lymphoma patients is proposed.
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The high level expression of somatostatin receptors (SSTR) on various tumor cells has provided the molecular basis for successful use of radiolabeled octreotide/lanreotide analogs as tumor tracers in nuclear medicine. The vast majority of human tumors seem to overexpress the one or the other of five distinct hSSTR sub-type receptors. Whereas neuroendocrine tumors frequently overexpress hSSTR2, intestinal adenocarcinomas seem to over-express more often hSSTR3 or hSSTR4, or both of these hSSTR. ⋯ In conclusion, several radioligands have been implemented on the basis of peptide receptor recognition throughout the last decade. A plentitude of preclinical data and clinical studies confirm "proof-of-principle" for their use in diagnosis as well as therapy of cancer patients. However, an optimal radiopeptide formulation does not yet exist for receptor-targeted radionuclide therapy.