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Purpose: The different stages in idiopathic retroperitoneal fibrosis (IRF) are generally assessed by assay of inflammatory markers and analysis of contrast-enhanced CT images of the retroperitoneal mass. We investigated the potential role of F-FDG PET/CT in this clinical setting. Methods: F-FDG uptake was assessed visually and semiquantitatively (using maximum standardized uptake values, SUVmax) in images of the abdominal mass in 22 patients prospectively enrolled from June 2008 to December 2010 who underwent a total of 33 PET/CT studies. The accuracy in discriminating active from inactive disease was calculated assuming as reference a biochemical instrumental evaluation of patients with IRF mostly based on the level of inflammatory indices and contrast enhancement (CE) of the mass at the time of each PET study. In particular, the relationship between SUVmax and CE, the latter calculated from the change in radiodensity (Hounsfield units) between the basal and postcontrast venous portal phases, was evaluated on a three-point scale (0 <20 HU, 1 20-30 HU, 2 ≥30 HU). SUVmax and CE scores were correlated with the erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) levels. The value of PET/CT in assessing the variation of disease activity over time was also investigated by analysing the changes in metabolic volume (MV) of the retroperitoneal lesion between repeat patient studies. Results: PET/CT accurately discriminated (93.9 %) active from inactive disease. Significant agreement ( p < 0.01) was observed between visual and semiquantitative analysis of F-FDG uptake, and CE score. A significant correlation ( p < 0.01) was found among SUVmax, CRP levels (rho = 0.54) and ESR (rho = 0.55). Corresponding variations in MV and CE score were observed in patients with multiple studies ( p < 0.01; rho = 0.68). Conclusion: F-FDG PET/CT may be considered an alternative imaging method for the assessment of different stages of IRF. [ABSTRACT FROM AUTHOR]

Abstract: Radiofrequency thermal ablation (RFTA) is a local tumor-destructing technique that can potentially modulate the host immune response through mechanisms that are not clearly defined. We assessed whether RFTA could affect multiple systemic inflammatory and immunological parameters, including CD25+Foxp3+ cells, in patients with primary or metastatic lung tumors. Three days after RFTA, a moderate and temporary systemic inflammatory response developed, as demonstrated by the increase in peripheral neutrophils and monocytes and in plasma levels of proinflammatory chemokines (MIP-1α, MIP-1β, eotaxin, and interleukin[IL]-8) and acute phase reactants (complement C3 and C4, serum amyloid, α1 antichymotrypsin, and C-reactive protein). Moreover, we found a concomitant release of the anti-inflammatory factor IL-10. Thirty days after RFTA, a significant reduction in CD25+Foxp3+ counts with an increase in CD4+ T-cell proliferation and number of interferon-γ-secreting cells was observed. The reduction in CD25+Foxp3+ cells lasted up to 90 days after treatment. The use of RFTA in lung cancer patients has an immunomodulatory activity: it induces a self-limiting systemic inflammation early and later a reduction of circulating CD25+Foxp3+ Tregs. In addition to tumor ablation, downmodulation of this regulatory subset might be an important mechanism involved in the long-term clinical efficacy of RFTA. [Copyright &y& Elsevier]

Background and Aim of the Study: Aortic valve-sparing (AVS) procedures have been introduced to treat ascending aorta dilatation and aortic valve insufficiency in the presence of preserved native aortic valve leaflets. Although the surgical technique has been standardized, the choice of best type and size of Dacron graft to be used remains a matter of debate. Herein are presented preliminary results based on a patient-specific finite element model aimed at optimizing the Dacron prosthesis size and shape. Previously, finite element analysis (FEA) has been applied to investigate medical problems and, in particular, to better evaluate the pathophysiology of the aortic root. To date, however, such methodology has not been applied to the patient-specific evaluation of AVS postoperative results., Methods: The framework of the FEA study included four steps: (i) the creation of a mathematic model of the patient's aortic root; (ii) the creation of a model for two different Dacron grafts (the standard straight graft and a Valsalva graft), with sizes of each type ranging from 24 to 30 mm; (iii) a virtual computer-based simulation of the AVS procedure, using each graft; and (iv) a virtual computer-based simulation of the diastolic closure of the repaired valve and an evaluation of post-implant physiology, based on three parameters: the height of coaptation ratio (H(C)R); the length of coaptation ratio (L(C)R); and the distance between the central point of coaptation and the ideal geometrical centre (D(C))., Results: The simulation results of post-implant performance of the aortic valve revealed that both H(C)R and L(C)R were decreased as the graft size was increased, but no significant differences were identified between two types of graft. In contrast, the Valsalva graft, when compared to the standard straight graft, led to a significant reduction in D(C). The results in terms of H(C)R, L(C)R and D(C) recommended unequivocally, for the specific case under investigation, that a 30 mm straight graft and a 28 mm Valsalva graft would ensure the most physiological valve behavior for the patient under investigation., Conclusion: In evaluating the potential of a preoperative prediction of the optimal graft size, using FEA, the virtual simulation of the AVS procedure proved to be feasible and useful in predicting the postoperative physiology of the aortic root. In particular, this finite element model might have a clinical impact as may be used to optimize the surgeon's choice of prosthesis size.

In this paper we reported a novel method to detect and quantify dural ectasia in Marfan syndrome. Firstly, the dural sacs of 8 Marfan patients were segmented by applying an unsupervised Fuzzy C-Means method on T2-weighed magnetic resonance images. Then, for each patient a tubular model of the dural sac was extracted by detecting and removing the existent pathological extrusions. The segmented images together with the resulting tube were then rendered using a marching cubes algorithm. The proposed algorithm represents a first attempt to quantify and to morphologically characterize the pathological ectasia that usually accompanies the Marfan disorder. The generated 3D reconstruction and the opportunity to overlap them with a physiological model provides the clinician with a tool for a panoramic view of the structures and a means for a more accurate inspection of ectasia. In addition the extracted parameters furnish quantitative and reproducible measures that could be useful as discriminative indexes for an automatic and more objective diagnosis.

Multidetector computed tomography (MDCT) and magnetic resonance imaging (MRI) have a leading role in the diagnosis and evaluation of pulmonary arterial hypertension. Technical aspects, advantages, limitations and potential contraindications will be considered. MDCT has many advantages: 1) fast examination, 2) good identification of central and peripheral vessels, 3) good characterization of parenchymal findings, and 4) good evaluation of the heart and mediastinal structures. Limitations are: 1) the use of iodinated contrast material, and 2) radiation exposure. MRI allows: 1) cardiac morphological and functional studies, and 2) identification of central pulmonary arteries. Limitations are: 1) long scanning time, 2) poor definition of peripheral arteries, and 3) impossibility of pulmonary evaluation. MDCT and MRI findings allow: 1) quick diagnosis of pulmonary arterial hypertension, 2) differential diagnosis between primary and secondary forms, 3) evaluation of cardiac manifestations, and 4) morphological and functional follow-up studies in surgically treated and untreated patients.

Acute intramural aortic hematoma may result from ruptured vasa vasorum without intimal disruption (IMH hereafter) but can also be found in association with processes in which an intimal lesion is present, such as aortic dissections (AD), where the hematoma represents the acute thrombosis of the false lumen, or in penetrating atherosclerotic ulcers (PAU), where blood collects beyond the disrupted internal elastic lamina. As the clinical presentation of these conditions is very similar, imaging techniques should aim both to diagnose the hematoma and to characterize the underlying pathology. This review critically analyzes the diagnostic potential of several imaging methods based on personal experience and literature reports. Although intramural hematoma can be easily diagnosed unrespective of the tomographic imaging modality, it is usually difficult to distinguish between IMH and hematomas associated either to AD or to PAU. Indeed, only PAU related hematomas can be consistently diagnosed due to the high probability of unveiling the causative wall ulceration; conversely, the differential diagnosis between IMH and AD - associated hematomas is still matter of controversy. According to the literature, the two conditions cannot be differentiated by transesophageal echocardiography, though some reports state that a distinction might be made by MR imaging. As regards CT, only a small percentage of AD - associated hematomas exhibit clear evidence of a typical intimal flap, allowing for a safe diagnosis to be made: often, unfortunately, the intimal lesion subsequently found at surgery cannot be detected, yielding a picture of IMH. Therefore, the radiological report should give the same diagnostic probability to both conditions.