In our NB population (18)F-dopa PET/CT displayed higher overall accuracy than (123)I-MIBG scintigraphy. Consequently, we suggest (18)F-dopa PET/CT as a new opportunity for NB assessment.

Our results confirm the good agreement between (18)F-DOPA PET/CT and (123)I-MIBG scan in patients affected by NB relapse. In time-to-event analyses, (123)I-MIBG scan and (18)F-DOPA PET/CT scores were independently and significantly associated with disease progression.

The discordant topography between atrophy and hypometabolism reported in AD is already present at the aMCI stage. Posterior cingulate-precuneus hypometabolism seemed to be an early sign of memory deficit, whereas hypometabolism in the left temporal cortex marked the conversion to AD.

Incomplete response to therapy may compromise the outcome of children with advanced neuroblastoma. In an attempt to improve tumour response we incorporated 131 I-metaiodobenzylguanidine ( 131 I-MIBG) in the treatment regimens of selected stage 3 and stage 4 patients. Between 1986 and 1997, 43 neuroblastoma patients older than 1 year at diagnosis, 13 with stage 3 (group A) and 30 with stage 4 disease (group B) who had completed the first-line protocol without achieving complete response entered in this study. 131 I-MIBG dose/course ranged from 2.5 to 5.5 Gbq (median, 3.7). The number of courses ranged from 1 to 5 (median 3) depending on the tumour response and toxicity. The most common acute side-effect was thrombocytopenia. Later side-effects included severe interstitial pneumonia in one patient, acute myeloid leukaemia in two, reduced thyroid reserve in 21. Complete response was documented in one stage 4 patient, partial response in 12 (two stage 3, 10 stage 4), mixed or no response in 25 (ten stage 3, 15 stage 4) and disease progression in five (one stage 3, four stage 4) Twenty-four patients (12/13 stage 3, 12/30 stage 4) are alive at 22–153 months (median, 59) from diagnosis. 131 I-MIBG therapy may increase the cure rate of stage 3 and improve the response of stage 4 neuroblastoma patients with residual disease after first-line therapy. A larger number of patients should be treated to confirm these results but logistic problems hamper prospective and coordinated studies. Long-term toxicity can be severe. © 1999 Cancer Research Campaign

Giant cell arteritis (GCA) is the most common vasculitis affecting medium and large vessels. It shows a close clinical association with polymyalgia rheumatica (PMR), a musculoskeletal inflammatory disorder, which is clinically characterized by girdles pain and stiffness. 18F-Fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) is an effective tool for the diagnosis, grading, and follow-up of patients affected by GCA involving the aorta and its proximal branches, but the lack of a standardized method for the assessment of vascular inflammation remains a critical issue, potentially leading to misclassification. In our systematic review, including 19 original articles for a total of 442 GCA patients (with or without PMR symptoms) and 535 healthy controls, we described the different qualitative, semiquantitative and combined methods that have been proposed throughout the literature for assessing the presence and grading the severity of GCA-related vascular inflammation on 18F-FDG PET scans, focusing on the diagnostic performance and examining their respective advantages and limitations. The majority of the included studies adopted qualitative methods of PET image analysis, which are less sensitive but more specific than semiquantitative ones. Among the semiquantitative approaches, the aortic-to-blood pool uptake ratio of the aortic arch seems to be the most accurate method.

A novel approach is presented for the solution of production planning problems for multiproduct processes. A mixed‐integer programming (MIP) scheduling model is analyzed off‐line to obtain a convex approximation of feasible production levels and a convex underestimation of total production cost as a function of production levels. The two approximating functions are expressed via linear inequalities that involve only planning variables yet provide all the relevant scheduling information necessary to solve the planning problem with high quality. A rolling horizon algorithm is also presented for generation (if necessary) of detailed schedules. © 2007 American Institute of Chemical Engineers AIChE J, 2007

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Several studies have highlighted the role of vascular 18 F-NaF uptake as a marker of ongoing calcium deposition. However, accumulation of 18 F-NaF is often inconsistent with localization of arterial plaque. Calcification activity and thus 18 F-NaF uptake might prevail in the earlier plaque stages. To test this hypothesis, we evaluated 18 F-NaF uptake in plaque of 3 different densities, using density as a marker of calcification progression. We also tested whether attenuationweighted image reconstruction affects 18 F-NaF uptake in the different plaque stages. Methods: Sixty-four oncologic patients (14 men and 50 women; mean age, 65.3 ± 8.2 y; range, 26-81 y) underwent 18 F-NaF PET/CT. A volume of interest was drawn on each plaque within the infrarenal aorta to assess mean standardized uptake value and attenuation (in Hounsfield units [HU]). Plaque was then categorized as light (,210 HU), medium (211-510 HU), or heavy (.510 HU). Standardized uptake value was normalized for blood 18 F-NaF activity to obtain the plaque target-to-background ratio (TBR). During this process, several focal, noncalcified areas of 18 F-NaF were identified (hot spots). The TBR of the hot spots was computed after isocontour thresholding. The TBR of a noncalcified control region was also calculated. In 35 patients, the TBR of nonattenuation-corrected images was calculated. Results: The average TBR was highest in light plaque (2.21 ± 0.88), significantly lower in medium plaque (1.59 ± 0.63, P , 0.001), and lower still in heavy plaque (1.14 ± 0.37, P , 0.0001 with respect to both light and medium plaque). The TBR of the control region was not significantly different from that of heavy plaque but was significantly lower than that of light and medium plaque (P , 0.01). Hot spots had the highest absolute TBR (3.89 ± 1.87, P , 0.0001 vs. light plaque). TBRs originating from non-attenuation-corrected images did not significantly differ from those originating from attenuation-corrected images. Conclusion: Our results support the concept that 18 FNaF is a feasible option in imaging molecular calcium deposition in the early stages of plaque formation, when active uptake mechanisms are the main determinants of calcium presence, but that retention of 18 F-NaF progressively decreases with increasing calcium deposition in the arterial wall. Our data suggest that nonattenuation-corrected reconstruction does not significantly affect evaluation of plaque of any thickness.