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Background: This study seeks to validate a radiological classification system of spontaneous upper urinary tract rupture (sUUTR) and to analyse its relationship with clinical, laboratory and radiological characteristics of sUUTR. Methods: We analysed data from 66 patients with a computerised tomography (CT)-proven sUUTR treated with ureteral or nephrostomy catheter po-sitioning. Comorbidities were scored with the Charlson Comorbidity Index (CCI). All CT scans were reviewed by two experienced radiologists and one urologist, who classified sUUTR in (a) local spread, (b) free fluid and (c) urinoma. Interobserver agreement for radiological score was evaluated with the Intraclass Correlation Coefficient (ICC) and Cohen’s Kappa analyses. Descriptive statistics and logistic regression models verified the association between clinical variables and sUUTR severity. Results: The interobserver agreement for sUUTR classification was high among radiologists and between the radiologists and the urologist (all Kappa > 0.7), with an overall high interrater reliability (ICC 0.82). Local spread, free fluid and urinoma were found in 24 (36.4%), 39 (59.1%) and 3 (4.5%) cases, respectively. Patients with free fluid/urinoma had higher rate of CCI ≥ 1 than those with local spread (40.5% vs. 16.7%, p = 0.04). Intraoperative absence of urine extravasation was more frequently found in patients with local spread than those with free fluid/urinoma (66.7% vs. 28.6%, p < 0.01). Multivariable logistic regression analysis revealed that local spread (OR 4.5, p < 0.01) was associated with absence of contrast medium extravasation during pyelography, after accounting for stone size, fever and CCI. Conclusions: The analysed sUUTR classification score had good inter/intra-reader reliability among radiologists and urologists. Absence of urine extravasation was five times more frequent in patients with local spread, making conservative treatment feasible in these cases.

Background: The aim of this study was to evaluate enoximone echocardiography (EE) for the identification of residual myocardial viability in postinfarction patients. Findings obtained during EE were compared with those acquired by myocardial uptake of fluorine-18 fluorodeoxyglucose (18F-FDG) positron emission tomography (PET) and functional follow-up results. Methods: Twenty-five patients underwent EE and PET 18F-FDG studies. An asynergic segment was considered as having contractile enhancement when the wall motion score decreased by >= 1 grade during EE and was defined as viable if 18F-FDG uptake score was >= 2 grade on PET. Results: Of 293 dysfunctional segments at baseline, 139 (47%) were viable by PET criteria; 117 (40%) had contractile enhancement induced by enoximone (P = 0.07). Agreement between EE and PET was found in 75% of involved segments (K = 0.46, P < 0.001). The majority of discrepancies (65%, P < 0.01) were mainly due to discordant segments in which PET revealed evidence of 18F-FDG uptake but EE showed no change in wall motion. In 179 revascularized segments, negative predictive value for functional recovery of both tests reached the same value (89% for both), whereas positive predictive value was 82% for EE and 68% for PET, respectively (P < 0.05). Sensitivity was 85% for EE and 88% for PET (P = ns); specificity was 87% and 70%, respectively (P < 0.01). Conclusions: EE yields a fair concordance with PET study. Compared with PET, despite a similar negative accuracy, EE shows a greater specificity for prediction of function recovery after revascularization. (Echocardiography 2010;27:544-551). RI Balbarini, Alberto/G-8753-2011

SPECT studies of regional cerebral perfusion with a high-resolution system were compared to PET studies of regional cerebral glucose utilization (rCMRglc) in 21 patients with probable Alzheimer's disease (AD). Ten normal subjects were also evaluated with SPECT and 10 with PET. METHODS: rCMRglc (for PET) and counts (for SPECT) in the associative cortices were normalized to the average rCMRglc, and counts in the calcarine cortex and basal ganglia were considered as a "reference area" to obtain a ratio. The ratio differences between patients and controls were tested with ANOVA performed separately for PET and SPECT. RESULTS: The difference between probable AD patients and controls was significant for both PET (p < 0.00001) and SPECT (p < 0.005); this difference was significant for the frontal, temporal and parietal cortices (p < 0.0001) for PET, and for the temporal (p < 0.005) and parietal (p < 0.001) cortices for SPECT. Temporo-parietal defects were detected in all subjects with PET and in 90% with SPECT. CONCLUSION: PET and SPECT are able to detect characteristic temporo-parietal abnormalities in probable AD. However, the presence of abnormalities in other associative areas is better evaluated with PET.

Prader-Willi syndrome (PWS) is a multi-system disorder characterized clinically by abnormal mental and physical development. PWS patients have a deletion in an imprinted region on paternal chromosome 15 (15q11-13), maternal disomy for this segment, or rarely, a chromosomal imprinting center deletion that gives rise to suppression of the equivalent paternal genes. Within the affected segment of chromosome 15 are genes encoding the alpha(5), beta(3) and gamma(3) subunits of the gamma-aminobutyric acid type-A (GABA(A)) receptor. Therefore, altered neurobehavioral function could arise in PWS due directly to altered GABA(A) receptor composition and expression, or alternatively, from brain developmental and maturational effects of these or other genes in the imprinted region. The aim of the present study was to assess cerebral GABA(A) receptors in PWS with the use of positron emission tomography of the benzodiazepine binding site employing [11C]flumazenil ([11C]FMZ). A reduction in [11C]FMZ binding was found predominantly in the cingulate, frontal and temporal neocortices and insula in six adult PWS patients compared to nine normal subjects. A possible role for the deleted beta(3) subunit gene in PWS is supported in part by the wide cortical distribution of its mRNA expression and the effects of experimental knockouts on benzodiazepine binding described in prior studies. Altered GABA(A) receptor composition or number in these cortical regions may account for neurobehavioral abnormalities in PWS including mild mental retardation, poor impulse control, and impaired responses to somatic pain.

Background. This study retrospectively assessed, with an intention-to-treat analysis, the effect of kidney-pancreas transplantation (KP) on survival and cardiovascular outcome in type 1 diabetic uremic patients. Methods. A total of 351 uremic type 1 diabetic patients were enrolled on a waiting list for KP: 130 underwent KP transplantation, 25 underwent kidney transplantation alone (KA), whereas 196 patients remained on dialysis (WL). The three populations had similar cardiovascular conditions. Actuarial survival rates and causes of death were recorded over a period of seven years. Finally, 23 KP and 13 KA patients underwent left radionuclide ventriculography, during a follow-up of four years. Results. In the entire group of 351 patients the seven-year survival rate was 77.4% for KP, 56.0% for KA and 39.6% for WL (KP vs. WL, P = 0.01). Cardiovascular death rate was 7.6% in KP, 20.0% in KA and 16.1% in WL (KP versus WL, P = 0.03; KP vs. KA, P = 0.16). In the subsample studied with radionuclide ventriculography, left ventricular ejection fraction improved in KP, but did not in KA, with significant differences between groups at two and four years. At four years only the KP patients presented normal values of diastolic parameters, including the peak filling rate, time-to-peak filling rate, and peak filling rate/peak ejection rate ratio. Glycated hemoglobin was negatively associated with the ejection fraction, peak filling rate and peak filling rate/peak ejection rate ratio, and positively associated with the time-to-peak filling rate. Conclusions. Normalization of blood glucose metabolism and improvement of blood pressure control obtained with KP transplant is associated with positive effects on survival, cardiovascular death rate, and left ventricular function

Emission tomography techniques and, in particular, positron emission tomography (PET) enable the in vivo study of several physiological and neurochemical variables in human subjects using methods originally developed for quantitative autoradiography. In particular, PET allows one to evaluate in human subjects: (a) the effect of specific neurochemical challenges on regional brain function at rest or under activation; (b) the activity of neurotransmitters and the regional expression of specific molecular targets during pathology including their modulation by drug treatment; (c) the kinetics of drug disposition and activity directly in the target organ. This is of primary interest in the field of biological psychiatry and in psychoactive drugs development, where it is particularly difficult to reproduce human diseases using animal models in view of the peculiarity of this field and the large heterogeneity of each psychiatric illness also inside the same clinical definition. The aim of this paper is to review the principal strategies and the main results of the use of PET in psychopharmacology.

Introduction: The aim of our study is to analyze the relationship between tumor growth and tumor hypoxia in an orthotopic glioma murine model by using a multimodal procedure, and to compare the features of the different imaging techniques in revealing hypoxia induction. Materials and methods: Engineered U251 cells were gently provided by Dr. Giovanni Melillo, National Cancer Institute, Frederick (MD). These cells express the luciferase reporter gene under control of a constitutive promoter (U251-LUC) or under control of three copies of a Hypoxic Responsive Element (U251-HRE). Cells has been analyzed by means of three different approaches: 1) In vitro evaluation of transcriptional activation of HIF-1? at different times after deferoxamine (DFX) treatment by immunocytochemistry (ICC). 2) In vivo analysis of tumoral progression in orthotopic murine models obtained by stereotaxic injection of 10^5 glioma cells; animals were monitored weekly with BLI (CCD camera), PET ([18F]FDG,[18F]FAZA,[18F]FLT) and MRI to evaluate tumoral progression and hypoxia activation. 3)Ex vivo analysis by H&E staining and hypoxia markers (HIF-1? and CAIX) were performed. Results: In vitro studies showed no differences among the two cell lines as regards to HIF-1? activation kinetic with a peak of activation between 3 and 6h and a decrease at 20h. In vivo, U251-HRE model showed a detectable and progressive luciferase activity induction starting at 18 days from injection demonstrating that luminescence expression is dependent on HRE-mediated activation. On the other hand, in U251-LUC model luciferase activity was detectable immediately after injection and remained proportional to tumor growth. Lesions were highly proliferative ( [18F]FLT) but hypo-metabolic ([18F]FDG). In partial agreement with the results of U251-HRE, a hypoxia dependent [18F]FAZA uptake was observed at later times (30 days). MRI provided morphological characterization and diffusion studies showing hypoxic necrotic areas only at later days. Ex vivo H&E staining and immunohistochemistry (HIF-1? and CAIX) performed after 30 days confirmed in vivo results including the presence of hypoxic regions. Conclusions: This study demonstrates that the U251-HRE orthotopic murine model may be proposed as a predictive and reliable tool to evaluate hypoxia dependent processes of human glioma in preclinical studies by BLI. Differences among the three imaging techniques may be related to methods sensitivity. Further ex vivo post mortem measurements of HIF-1 and CAIX at earlier times will be performed. Additional studies will be conducted to understand the clinical meaning of early or delayed hypoxia identification in terms of response to treatment.

Purpose. We investigated 201T1 myocardial uptake with(out) nonuniform attenuation compensation in ischemic myocardiopathy patients. The segmental patterns of the two types of SPECT images were compared with PET [13N]NH3 studies performed in the same patient. PET images were taken as reference and the diagnostic accuracy of SPECT with(out) attenuation correction was evaluated. Material and methods. During the SPECT study transmission and emission data were simultaneously recorded by a triple head gamma camera equipped with fan beam collimators and a 99mTc transmission line source (740MBq). SPECT and PET images, the former reconstructed with(out) attenuation correction, were corecorded and reoriented along the short axis. The left ventricular wall was divided into 11 segments and segmental activity normalized to maximum in each study. Results. Statistically significant differences were found between PET/(un)corrected SPECT ratios in posterior and septal segments. In these myocardial regions, attenuation correction compensates for attenuation artifacts, by correcting the underestimation of radioactivity concentration caused by radiation absorption. A statistically significant difference was also found in midventricular anterior and apical segments (p

Background. To assess the potential usefulness of F-18-FDG/PET and spiral-CT images concurrent assessment and coregistration in staging mediastinal lymph node involvement in patients with non small cell lung cancer. Methods, 28 patients waiting to undergo surgical treatment underwent spiral-CT and PET examinations on the same day. The results of the two studies were interpreted separately, together (CT&PET) and following their fusion in a single image (CT+PET). Results of spiral-CT, PET, CT&PET and CT+PET were assessed with respect to the histological diagnosis. Results, A correct assessment of mediastinal lymph nodes was achieved by spiral-CT in 21 of the 28 patients, in 22 of the 28 patients by PET, in 24 patients by CT&PET and in 25 patients by CT+PET. Conclusions. CT+PET is more accurate than spiral-CT and PET alone in staging mediastinal lymph node involvement in lung cancer patients, with possible implications for their prognosis and therapy. RI Lucignani, Giovanni/C-6773-2008

An improvement of regional and global left ventricle dysfunction can be achieved in patients with coronary artery disease either by coronary revascularization with percutaneous transluminal coronary angioplasty or coronary artery bypass grafting. Several techniques have been developed to identify dysfunctional but viable myocardium. In the last decade, positron emission tomography (PET) with 18F-fluorodeoxyglucose (18F-FDG) has been used for the detection of hibernating myocardium. It can accurately predict the recovery of abnormal wall motion in hibernating segments prior to surgery. In particular, assessment of viability with 18F-FDG is indicated in high-risk surgical candidates being considered for revascularization or transplantation. Moreover, patient selection criteria and economic consideration are also relevant for cost-effective use of the technique.

Background. The clinical work-out of patients undergoing coronary revascularization includes the assessment of myocardial viability. This approach has to be defined in the different classes of patients. The aim of this study was to evaluate the predictive prognostic value of different techniques on outcome following PTCA in patients with moderate left ventricle dysfunction (left ventricle EF≥40%). Methods. Seventeen patients with EF≥40% and undergoing PTCA were studied by 201Tl rest/redistribution, 18F-FDG and 99mTc-MIBI rest. Regional kinesis was scored by echo, dividing left ventricle in 11 segments. The echo evaluation was repeated at 1 and 6 months after revascularization. Results. Global EF was 52.5±7% and 69 segments had abnormal kinesis. Patients underwent stress/rest 99mTc-MIBI SPET, rest/redistribution 201Tl SPET and rest 18F-FDG PET. Among the 11 segments defined on echo-matched tomographic images, the one with the highest activity at stress was assumed as reference (actiyity=100%). If ≥50% of reference segment, 18F-FDG and 201Tl uptakes were considered significant. After PTCA, the echo-follow-up did not demonstrated significant improvement of left ventricle function at 30 days after PTCA (EF 56±6%) as well as at 6 months (EF 56±9%). The positive predictive value under these conditions resulted: 46.5% with 99mTc-MIBI rest, 47.4% with 201Tl rest-redistribution and 45.7% with 18F-FDG. Conclusions. In summary, in the class of patients with moderately compromised function, considering as reference the improved regional kinesis after PTCA, 99mTc-MIBI at rest, 201Tl rest/redistribution and 18F-FDG do not exhibit a clear predictive value; patient population is then a highly relevant point to establish the accuracy of these diagnostic procedures.

Small-animal positron emission tomography (PET) and single photon emission tomography (SPECT) are invaluable tools in drug discovery and in assessing novel therapeutic agents. In a typical small-animal PET or SPECT imaging session, a radiopharmaceutical is administered and the kinetics of its distribution tracked. Whereas the PET and SPECT protocols for the radiotraceras used in clinical practice are well established, at least for the radiotracers that are used in clinical practice, the acquisition, reconstruction and data analysis procedures applied in small rodents are heterogeneous among centres, often being determined by the scanner characteristics and by the animal models and anaesthesia procedures used in the laboratory. This review, intended to serve as a guide to preclinical PET and SPECT experiments, aims to familiarise the reader with the aspects of PET and SPECT that pertain to in vivo preclinical acquisitions and, in particular, with the technical and methodological know-how that is needed for better application of radionuclide imaging techniques in preclinical cancer research.

This multicenter study examined F-18-FDG PET measures in the differential diagnosis of Alzheimer's disease (AD), frontotemporal dementia (FTD), and dementia with Lewy bodies (DLB) from normal aging and from each other and the relation of disease-specific patterns to mild cognitive impairment (MCI). Methods: We examined the F-18-FDG PET scans of 548 subjects, including 110 healthy elderly individuals ("normals" or NLs), 114 MCI, 199 AD, 98 FTD, and 27 DLB patients, collected at 7 participating centers. Individual PET scans were Z scored using automated voxel-based comparison with generation of disease-specific patterns of cortical and hippocampal F-18-FDG uptake that were then applied to characterize MCI. Results: Standardized disease-specific PET patterns were developed that correctly classified 95% AD, 92% DLB, 94% FTD, and 94% NIL. MCI patients showed primarily posterior cingulate cortex and hippocampal hypometabolism (81%), whereas neocortical abnormalities varied accordi! ng to neuropsychological profiles. An AD PET pattern was observed in 79% MCI with deficits in multiple cognitive domains and 31% amnesic MCI. F-18-FDG PET heterogeneity in MCI with non-memory deficits ranged from absent hypometabolism to FTD and DLB PET patterns. Conclusion: Standardized automated analysis of F-18-FDG PET scans may provide an objective and sensitive support to the clinical diagnosis in early dementia. Key Words: F-18-FDG PET; Alzheimer's disease; frontotemporal dementia; Lewy body dementia; mild cognitive impairment; normal aging; hippocampus.

The differential diagnosis among various types of non-functioning sellar and parasellar rumours is sometimes difficult using currently available methods of morphological imaging. The aim of this study was to define whether assessment of the uptake of [F-18]fluoro-ethyl-spiperone (FESP) with positron emission tomography (PET) could be helpful for the differential diagnosis of pituitary adenomas and other parasellar lesions, and for establishing the appropriate therapeutic approach, The population examined comprised 16 patients with the diagnosis of primary tumour of the sellar/parasellar region who were waiting to undergo surgical treatment. The results demonstrated that PET with [F-18]FESP is a very specific method for differentiating adenomas from craniopharyngiomas and meningiomas. The visual interpretation of images allows such differentiation at approximately 70 min after tracer injection. Semiquantitative analysis of the dynamic PET data confirmed the results of visual interpretation, demonstrating that the uptake of [F-18]FESP was consistently (i.e. throughout the series) at least two-to threefold higher in non-functioning adenomas than in other parasellar rumours as early as 70 min after tracer injection, and that it increased still further thereafter. It is concluded that PET with [F-18]FESP might be of clinical value in those cases in which the differential diagnosis among various histological types of sellar tumour is uncertain with conventional methods.

Estrogen receptors are expressed in several brain areas of various animal species, and steroid hormones exert physiologic and biochemical effects on the central nervous system. The aim of the present study was to evaluate in female adult rats, the suitability of 16 alpha [18F]fluoro-17 beta-estradiol ([18F]FES), a selective estrogen receptor ligand, for the in vivo assessment of brain estrogen receptors. This was considered to be a preliminary step in evaluating the potential usefulness of [18F]FES for studies of cerebral estrogen receptors with positron emission tomography (PET) in nonhuman primates and human subjects. We evaluated (a) the time course of the metabolic degradation of [18F]FES in blood; (b) the time course of distribution of the tracer in discrete cerebral areas; (c) the inhibitory effect of increasing doses of cold estradiol on cerebral [18F]FES uptake; and (d) the possibility of in vivo quantification of estrogen receptor binding parameters using both equilibrium and dynamic kinetic analyses. We quantified [18F]FES binding to estrogen receptors using both equilibrium and dynamic kinetic analyses. The results of this study indicate that [18F]FES is a suitable tracer for the measurement of estrogen receptors in the pituitary and hypothalamus, using either the equilibrium or the kinetic analysis. However, [18F]FES is inadequate for the in vivo investigation of estrogen binding sites in brain areas with low receptor density, such as the hippocampus.

The distribution of 99mTc-methoxy-isobutyl-isonitrile (99mTc-MIBI), assessed by single photon emission computed tomography (SPECT) was compared to the distribution of 2-[18F]-2-deoxy-D-glucose ([18F]FDG) assessed with positron emission tomography (PET) under fasting conditions, in 21 patients with coronary artery disease (CAD) and severe left ventricular dysfunction in order to evaluate the potential usefulness of SPECT/99mTc-MIBI for the identification of viable myocardium. Stress and rest SPECT/99mTc-MIBI studies were scored based on the percent of 99mTc-MIBI uptake defined by semi-quantitative circumferential-profile analyses. PET metabolic studies with [18F]FDG under fasting conditions, were adopted as a standard of viability. The results of the comparison of 99mTc-MIBI and [18F]FDG distribution showed that among the segments with stress hypoperfusion, [18F]FDG uptake was present in 95% of the segments that had > 40% of the peak tracer uptake at the rest SPECT/99mTc-MIBI study. [18F]FDG uptake was also present, however, in 25% of the segments that had < 40% uptake at the rest SPECT/99mTc-MIBI scintigraphy. We conclude that in patients with CAD the pattern of 99mTc-MIBI distribution appears to underestimate the extent of viable myocardium but only in those regions that are very severely hypoperfused.

AIM: Increasing ageing of the population and tumor incidence, along with worldwide rationing of the resources for public health systems, spur the use of economic analyses for the choice of strategies and technologies in the assessment and management of cancer patients. Incidence and clinical managing of tumors vary in different countries even if positron emission tomography (PET) with 2-deoxy-2-[18F]-fluoro-D-glucose (FDG) is becoming a routine clinical method for diagnosis, staging, treatment monitoring and follow-up in a variety of tumors. Available data indicate that PET can be considered a superior alternative or complementary tool to other well-established methods. However, in spite of the above and of the rapidly increasing number of PET centers in Europe, USA and Japan, only a few studies have dealt with some of the economic aspects raised by the clinical use of PET because of differences in values of reimbursements and health costs. The main aim of this study is to propose and discuss an economic model of analysis for PET applications in the field of detection and management of pulmonary tumors. METHODS: In this study 2 assessments were performed by decision tree analysis on the economic impact of the availability of PET on decision-making processes for 2 conditions: solitary pulmonary nodules assessment and non-small-cell lung cancer (NSCLC) staging. In order to define a methodology consistent with the system of reimbursement and the prevalent clinical views of the Italian National Health Service, data on costs, death probability, and life expectancy were gathered from the literature and from the Italian system of reimbursement (ROD-DRGs). RESULTS: The results of the cost minimization analysis demonstrate that the use of PET in the diagnostic path for the workup of patients with SPN reduces the overall diagnostic costs, by approximately 50 Euro per patient, by reducing inappropriate invasive diagnostic investigation and their complications. The results of the cost effectiveness analysis demonstrate that the use of PET in the diagnostic path for the staging of patients with NSCLC reduces the overall diagnostic costs by approximately 108 Euro for added year, by reducing inappropriate surgical interventions and their complications. CONCLUSION: Both analyses are based on standard methods used in the literature, so our conclusions can be compared with results and assessments of similar studies in different countries and health care systems. Also in the Italian case, the use of an economic assessment provides relevant information on the efficacy and effectiveness of PET.

Positron emission tomography (PET) allows the non invasive and quantitative measurement of regional distribution of molecules labeled with positron emitting isotopes such as: nitrogen, oxygen, carbon and fluorine. The aim of the present paper is to review the applications of this methodology for the in vivo study of the kinetics and of the mechanism of action of drugs in humans.

Emission tomography techniques and, in particular, positron emission tomography (PET) enable the in vivo study of several physiological and neurochemical variables in human subjects using methods originally developed for quantitative autoradiography. In particular, PET allows one toevaluate in human subjects: (a) the effect of specific neurochemical challenges on regional brain function at rest or under activation; (b) the activity of neurotransmitters and the regional expression of specific molecular targets during pathology including their modulation by drug treatment; (c) the kinetics of drug disposition and activity directly in the target organ. This is of primary interest in the field of biological psychiatry and in psychoactive drugs development, where it is particularly difficult to reproduce human diseases using animal models in view of the peculiarity of this field and the large heterogeneity of each psychiatric illness also inside the same clinical definition. The aim of this paper is to review the principal strategies and the main results of the use of PET in psychopharmacology.

Local hepatic blood flow was measured by use of the 133Xe clearance technique following the direct injection of the tracer into the right lobe of the liver in twenty-two patients without liver disease. The clearance of the radioactive gas from the organ was monitored by means of a gamma-camera. The analysis of the wash-out curves, in order to measure hepatic blood flow, was performed by two methods based on a monocompartmental and bicompartmental model, respectively. A large variability of the results was observed, possibly explained by inhomogeneous perfusion and inhomogeneity of the liver parenchyma. The complexity of the Xenon kinetics in the liver requires at least a bicompartimental model for the analysis of the clearance curves. The method is of limited usefulness in the assessment of liver function activity.

A procedure for patient repositioning and compensation for misalignment between transmission and emission data in positron emission tomography (PET) heart studies has been developed. Following the transmission scan (TR1), patients are moved from the scanner bed for the administration of the tracer, and repositioned when ready for the emission scan (EM1). A short postinjection transmission scan (TR2) is performed at the end of the EM1 study. TR1 and TR2 images are compared to recognize misalignment between transmission and emission studies. TR1 sinograms are compensated for misalignment to allow for a proper attenuation correction. The procedure has been tested on phantom and [18F]FDG PET heart studies. Misalignments down to 2.5 mm translation and 1 degree rotation in the transaxial plane and 4 mm in the axial direction can be recognized and compensated for. The procedure is suitable for clinical purposes, allowing reduction of patient time on the scanner bed, increased patient comfort and significant increase of patient throughput.