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Background: In the current clinical practice, radiometabolic therapy of Graves' disease is based on the administration of an amount of 131I-iodide defined according to two different modalities: administration of a fixed activity (up to a maximum of 555 MBq allowed by many national legislations on an outpatient basis) or an 131I-iodide activity individually defined so as to reach the certain fixed values of target thyroid-absorbed dose. The aim of this study was to prove the effectiveness of a personalized approach to cure Graves' disease based on the administration of a 131I activity defined according to the desired "optimal final thyroid mass." According to this model, one can predict the thyroid-absorbed dose following the administration of an activity as a function of the desired reduction of the baseline, pre-treatment mass of the gland. Methods: A total of 217 patients with Graves' disease were included in this study. They were randomly divided into five groups, of which four groups were divided based on fixed thyroid-absorbed dose value of 100 (Group A, n = 29), 200 (Group B, n = 25), 300 (Group C, n = 51), and 400 (Group D, n = 25), respectively, whereas patients of the final thyroid mass (mf) (Group V, n = 87) received a 131I activity calculated based on the desired "optimal" final thyroid mass according to the so-called "volume algorithm" approach. Results: At the 1-year follow-up, therapeutic success (i.e., a state of either hypothyroidism or euthyroidism) was achieved in 48% of patients in Group A (100 Gy), 64% in Group B (200 Gy), 78% in Group C (300 Gy), 96% in Group D (400 Gy), and 92% in Group V (mf). A significantly higher proportion of patients were was cured in Groups D and V (mf) than in Groups A, B, and C (P < 0.01). There was no statistical difference in cure rates between Groups D and V (mf). The median thyroid-absorbed dose was 407 Gy for Group D (400 Gy), significantly higher than 296 Gy for Group V (mf) (P < 0.001) and also significantly greater than the administered 131I activity (494 vs. 345 MBq, P < 0.001). Conclusions: This study indicates that the most effective thyroid-absorbed dose to be delivered for the radiometabolic therapy of patients with Graves' disease should not be based on a fixed dose but rather should be personalized. The new method based on thyroid mass reduction allows the optimization of 131I-iodide therapy for Graves' disease on an individual basis, achieving a high therapeutic efficacy while at the same time avoiding the administration of unjustified greater activities of 131I. [ABSTRACT FROM AUTHOR]

Purpose: Diffusion tensor imaging (DTI) is highly sensitive to noise and improvement of radiofrequency coil technology represents a straightforward way for augmenting signal-to-noise ratio (SNR) performance in magnetic resonance imaging (MRI) scanners. The aim of this study was to characterize the dependence of DTI measurements of fractional anisotropy (FA) and mean diffusivity (MD) on the choice of head coil, comparing two head coils with different functional designs and sensitivities., Methods: Fourteen healthy subjects underwent DTI acquisitions at 1.5 T. Every subject was scanned twice, using a standard quadrature birdcage head coil (coil-A) and an eight-channel array head coil (coil-B). FA and MD maps, estimated using both the linear least squares (LLS) and nonlinear least squares (NLLS) methods, were nonlinearly normalized into a standard space. Then, volumetric regions of interest encompassing typical white and gray matter structures [splenium of the corpus callosum (SCC), internal capsule (IC), cerebral peduncles (CP), middle cerebellar peduncles (MCP), globus pallidus (GP), thalamus (TH), caudate (CA), and putamen (PU)] were analyzed. Significant differences and trends of variation in DTI measurements were assessed by the Wilcoxon test for paired samples with and without Bonferroni correction for multiple comparisons, respectively., Results: The overall SNR of coil-B was 30% higher than that of coil-A. When comparing DTI measurements (coil-B versus coil-A), mean FA values (SCC, IC, and TH), mean MD values (IC, CP, GP, and TH), FA standard deviation (CP, MCP, GP, and CA), and MD standard deviation (IC, CP, TH, and PU) resulted decreased (significant difference, p(cor) < 0.05, or trend of variation, P(uncor) < 0.05) in several gray and white matter regions of the human brain. With the exception of CP, the results in terms of revealed significant difference or trend of variation were independent of the method (LLS and NLLS) used for estimating the diffusion tensor., Conclusions: In various gray and white matter structures, the eight-channel array head coil yielded more precise and accurate measurements of DTI derived indices compared to the standard quadrature birdcage head coil.

Objective: To determine plasma levels of homocysteine, folate, and vitamin B12 in patients with laryngeal cancer and a control group., Design: Analysis of homocysteine, folate, and vitamin B12 levels in 25 consecutive untreated patients with laryngeal carcinoma and 80 healthy control participants. The study and control groups were subdivided into smokers, ex-smokers, and nonsmokers, as well as drinkers and nondrinkers., Intervention: The AxSYM system was used to measure total homocysteine levels, and the ARCHITECT system (both Abbott-Diagnostics Division) was used to measure folate and vitamin B12 levels., Main Outcome Measures: Homocysteine, folate, and vitamin B12 levels., Results: The mean (SD) level of total homocysteine in patients with laryngeal carcinoma was 2.84 (1.62) mg/L vs 0.99 (0.24) mg/L in the control group (P <.001). The mean (SD) folate plasma level was 4.3 (2.2) ng/mL vs 7.9 (2.4) ng/mL (P <.001)., Conclusions: Metabolic alterations in homocysteine, folate, and vitamin B12 levels, especially hypofolatemia, could be associated with laryngeal cancer. Lengthier follow-up studies and larger groups of patients will help determine the real role of these metabolic alterations.