Functional Imaging In Patients Research Articles

Lipid-Lowering Medication and Outcomes After Anatomical and Functional Imaging in Suspected Coronary Artery Disease.

Anatomical and functional imaging identify different phenotypes of coronary artery disease (CAD) that may have implications for lipid-lowering medication (LLM). The aim of this study was to assess the associations between LLM and long-term outcomes after combined anatomical and functional imaging in patients with suspected obstructive CAD. Consecutive patients (n=1,973; 41% men; median age: 63 years) underwent coronary computed tomography angiography (CTA) because of suspected CAD. Patients in whom obstructive CAD was not ruled out by CTA underwent ischemia testing by positron emission tomography. Data on LLM purchases were collected until 2 years, and the combined endpoints of death, myocardial infarction, and unstable angina pectoris were assessed at a median of 6.7 years. After imaging, LLM was used by 24% of patients with no CAD, 51% of patients with nonobstructive CAD, 72% of patients with obstructive CAD on CTA without myocardial ischemia, and 91% of patients with myocardial ischemia. The use of LLM decreased during follow-up, with 77% of patients with myocardial ischemia using LLM for 2 years. The use ofLLM was associated with a lower annual rate of adverse events in patients with myocardial ischemia (6.1% vs 2.8%; P= 0.032) or obstructive CAD without myocardial ischemia (2.9% vs 1.4%; P = 0.004) but not in patients with nonobstructive CAD (1.5% vs 1.4%; P = 0.89) or no CAD (0.3% vs 0.3%; P = 0.68). The CAD phenotype defined by anatomical and functional imaging guides the use of LLM. The presence of myocardial ischemia and anatomical obstructive coronary lesions were associated with a long-term outcome benefit from LLM.

Down-modulation of functional ventral striatum activation for emotional face stimuli in patients with insula damage.

Insula damage results in substantial impairments in facial emotion recognition. In particular, left hemispheric damage appears to be associated with poorer recognition of aversively rated facial expressions. Functional imaging can provide information on differences in the processing of these stimuli in patients with insula lesions when compared to healthy matched controls (HCs). We therefore investigated 17 patients with insula lesions in the chronic stage following stroke and 13 HCs using a passive-viewing task with pictures of facial expressions testing the blood oxygenation dependent (BOLD) effect in predefined regions of interest (ROIs). We expected a decrease in functional activation in an area modulating emotional response (left ventral striatum) but not in the facial recognition areas in the left inferior fusiform gyrus. Quantification of BOLD-response in ROIs but also voxel-based statistics confirmed this hypothesis. The voxel-based analysis demonstrated that the decrease in BOLD in the left ventral striatum was driven by left hemispheric damaged patients (n = 10). In our patient group, insula activation was strongly associated with the intensity rating of facial expressions. In conclusion, the combination of performance testing and functional imaging in patients following circumscribed brain damage is a challenging method for understanding emotion processing in the human brain.

Imaging Evaluation of Kawasaki Disease.

This review provides the summary of the appropriate use of these modalities when caring for patients with Kawasaki disease at diagnosis and for long-term management. Kawasaki disease is an inflammatory syndrome of unknown etiology that can result in coronary artery dilations or aneurysms if left untreated in 25% of the patients and 3-5% in treated patients. In addition to coronary artery aneurysms, patients can have ventricular dysfunction, valvular regurgitation, aortic root dilation, and pericardial effusion due to inflammation of the myocardium. Noninvasive imaging modalities are important to these assessments. Echocardiography is the first-line noninvasive evaluation of coronaries and function. Cardiac magnetic resonance imaging is useful for functional assessment in long-term follow-up. Distal coronaries, thromboses, and stenoses are best evaluated by cardiac computed tomography. Future research should demonstrate the effectiveness of advanced functional imaging in patients with Kawasaki disease and decreased radiation from cardiac computed tomography.

Incremental prognostic value of vasodilator stress cardiovascular magnetic resonance over coronary computed tomography angiography in symptomatic patients

Abstract Funding Acknowledgements Type of funding sources: None. BACKGROUND Current guidelines recommend to perform noninvasive functional imaging in patients with obstructive coronary artery disease (CAD) on coronary computed tomography angiography (CCTA). However, the prognostic value of stress cardiovascular magnetic resonance (CMR) over traditional risk factors and CCTA is not known. PURPOSE To assess the incremental prognostic value of stress CMR beyond traditional risk factors and CCTA in patients with obstructive CAD on CCTA. METHODS Between 2008 and 2020, consecutive symptomatic patients without known CAD referred for CCTA were screened. Among those, patients with obstructive CAD (at least 1 ≥50% stenosis on CCTA) and referred for functional stress CMR were included and followed for the occurrence of major adverse cardiovascular events (MACE), defined by cardiovascular death or nonfatal myocardial infarction. Univariable and multivariable Cox regressions were performed to determine the prognostic value of CCTA and CMR findings. RESULTS Of 2,210 patients who completed the CMR protocol, 2,038 patients (46.5% male, mean age 69.8 ± 12.2 years) completed the follow-up (median 6.8 [IQR 5.9-9.2] years); 281 experienced a MACE (13.8%). Stress CMR was well tolerated without severe adverse events. Using Kaplan-Meier analysis, inducible ischemia and late gadolinium enhancement (LGE) were significantly associated with the occurrence of MACE (hazard ratio, HR: 4.51, [95%CI: 3.55-5.74]; and HR: 3.32, [95%CI: 2.55-4.32], respectively; both p < 0.001). In multivariable Cox regression, the presence of inducible ischemia and LGE were independent predictors of a higher incidence of MACE (HR: 3.97, [95%CI: 3.43-5.13]; HR: 2.30, [95%CI: 1.52-3.33]; respectively, both p < 0.001). After adjustment, stress CMR findings showed the best improvement in model discrimination and reclassification above traditional risk factors and CCTA findings (C statistic improvement: 0.08; NRI = 0.421; IDI = 0.047). CONCLUSIONS In symptomatic patients with obstructive CAD of unknown significance on CCTA, stress CMR has an incremental prognostic value to predict MACE over traditional risk factors and CCTA findings. Abstract Figure. Kaplan-Meier curves for MACE Abstract Figure. Competitive risk analysis

Vesicular monoamine transporters expression in pheochromocytomas and paragangliomas according to scintigraphy and positron emission tomography behavior.

The expression of vesicular catecholamine transporters (VMAT1 and 2) in pheochromocytomas (PHEOs) and paragangliomas (PGLs) and the possible relationships with [18F]FDOPA PET/CT and [123I]MIBG scintigraphy uptake are unknown. Our purpose was to investigate possible correlations of either VMAT1 and VMAT2 expression with the functional imaging in patients with PHEOs and PGLs. An observational 3-year time study was performed by enrolling 31 consecutive patients with PHEO (N.=17) or PGL (N.=14). They underwent the same diagnostic work-up; moreover, [123I]MIBG SPECT/CT (N.=20) and [18F]FDOPA PET/CT (N.=14) were performed in a subset of patients. After surgery, routine histology and semiquantitative analysis of VMAT1/VMAT2 immunoreactivity were carried out in all cases. VMAT1 immunoreactivity was found in all tumors, but two PHEOs. VMAT1 immunoreactivity was higher in PGLs than in PHEOs, though at not significant extent. Elevated VMAT2 immunoreactivity score was present in all but two negative tumors. Normal [123I]-MIBG uptake was independent from VMAT1/2 immunoreactivity. Patients undergoing [18F]FDOPA PET/CT showed a high score level of both VMATs and were detected by the technique in all cases. VMAT1 and VMAT2 are highly expressed in most tumors, though VMAT1 immunoreactivity is apparently prevalent in PGLs as compared to PHEOs. Presence and expression of VMAT1 and VMAT2 are not limiting factors for MIBG uptake. The status of VMAT expression might help to understand why the more frequently used radiotracers do not always have the expected diagnostic performance. Finally, the present study points out the importance of developing new radiotracers with higher sensitivity, specificity and accuracy consequently reducing healthcare costs.

Incremental prognostic value of vasodilator stress cardiovascular magnetic resonance over coronary computed tomography angiography in symptomatic patients

Current guidelines recommend to perform noninvasive functional imaging in patients with obstructive coronary artery disease (CAD) on coronary computed tomography angiography (CCTA). However, the prognostic value of stress cardiovascular magnetic resonance (CMR) over traditional risk factors and CCTA is not known. To assess the incremental prognostic value of stress CMR beyond traditional risk factors and CCTA in patients with obstructive CAD on CCTA. Between 2008 and 2020, consecutive symptomatic patients without known CAD referred for CCTA were screened. Among those, patients with obstructive CAD (at least 1 ≥ 50% stenosis on CCTA) and referred for stress CMR were included and followed for the occurrence of MACE, defined by cardiovascular death or nonfatal myocardial infarction. Of 2210 patients who completed the CMR protocol, 2038 patients (46.5% male, mean age 69.8 ± 12.2 years) completed the follow-up (median 6.8 [IQR 5.9–9.2] years); 281 experienced a MACE (13.8%). Stress CMR was well tolerated without severe adverse events. Using Kaplan-Meier analysis, inducible ischemia and late gadolinium enhancement (LGE) were significantly associated with the occurrence of MACE (hazard ratio [HR]: 4.51, [95% CI: 3.55–5.74]; and HR: 3.32, [95% CI: 2.55–4.32], respectively; both P < 0.001). In multivariable Cox regression, the presence of inducible ischemia and LGE were independent predictors of a higher incidence of MACE (HR: 3.97, [95% CI: 3.43–5.13]; HR: 2.30, [95% CI: 1.52–3.33]; respectively, both P < 0.001). After adjustment, stress CMR findings showed the best improvement in model discrimination and reclassification above traditional risk factors and CCTA findings (C statistic improvement: 0.08; NRI = 0.421; IDI = 0.047) ( Fig. 1 ). In symptomatic patients with obstructive CAD of unknown significance on CCTA, stress CMR has an incremental prognostic value to predict MACE over traditional risk factors and CCTA findings.

The Insula Is a Hub for Functional Brain Network in Patients With Anti-N-Methyl-D-Aspartate Receptor Encephalitis.

BackgroundIn recent years, imaging technologies have been rapidly evolving, with an emphasis on the characterization of brain structure changes and functional imaging in patients with autoimmune encephalitis. However, the neural basis of anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis and its linked cognitive decline is unclear. Our research aimed to assess changes in the functional brain network in patients with anti-NMDAR encephalitis and whether these changes lead to cognitive impairment.MethodsTwenty-one anti-NMDAR encephalitis patients and 22 age-, gender-, and education status-matched healthy controls were assessed using resting functional magnetic resonance imaging (fMRI) scanning and neuropsychological tests, including the Hamilton Depression Scale (HAMD24), the Montreal Cognitive Assessment (MoCA), and the Hamilton Anxiety Scale (HAMA). A functional brain network was constructed using fMRI, and the topology of the network parameters was analyzed using graph theory. Next, we extracted the aberrant topological parameters of the functional network as seeds and compared causal connectivity with the whole brain. Lastly, we explored the correlation of aberrant topological structures with deficits in cognitive performance.ResultsRelative to healthy controls, anti-NMDAR encephalitis patients exhibited decreased MoCA scores and increased HAMA and HAMD24 scores (p < 0.05). The nodal clustering coefficient and nodal local efficiency of the left insula (Insula_L) were significantly decreased in anti-NMDAR encephalitis patients (p < 0.05 following Bonferroni correction). Moreover, anti-NMDAR encephalitis patients showed a weakened causal connectivity from the left insula to the left inferior parietal lobe (Parietal_Inf_L) compared to healthy controls. Conversely, the left superior parietal lobe (Parietal_sup_L) exhibited an enhanced causal connectivity to the left insula in anti-NMDAR encephalitis patients compared to controls. Unexpectedly, these alterations were not correlated with any neuropsychological test scores.ConclusionThis research describes topological abnormalities in the functional brain network in anti-NMDAR encephalitis. These results will be conducive to understand the structure and function of the brain network of patients with anti-NMDAR encephalitis and further explore the neuropathophysiological mechanisms.

P2243CTCA alone demonstrates superior diagnostic accuracy, prognostic utility and is less expensive than CTCA combined with subsequent multi-modality functional imaging in patients with ischaemic symptoms

Abstract Background The evaluation of suspected ischaemic symptoms incorporates multi-modality anatomical and functional imaging tests. The 2016 update to the UK's NICE guidelines recommends CT coronary angiogram (CTCA) first line in patients without known coronary artery disease. Additive multi-modality functional imaging may provide synergistic diagnostic and prognostic information. Purpose To investigate the diagnostic accuracy, prognostic utility and cost of CTCA combined with subsequent multi-modality functional testing versus (vs) CTCA alone. Methods 772 consecutive patients were referred to a single UK tertiary centre with symptoms suggestive of ischaemia. 657 individuals (“CTCA group”) underwent CTCA alone, and 115 individuals (“Combined group”) underwent CTCA and then either perfusion cardiac MRI (n=25), stress echocardiogram (n=16), or myocardial perfusion scintigraphy (n=74). Patients underwent invasive angiography (n=79) +/− revascularisation at the discretion of the referring clinician. All readers and operators were aware of previous imaging findings. Revascularised patients (n=52) were excluded from long term follow-up. The remaining patients were followed-up for a mean of 38.1±17.4 months and the incidence of major adverse cardiovascular events (MACE) recorded. Costs were derived from the NICE guidelines. Results Baseline characteristics were similar between groups. The Combined group underwent significantly more invasive angiograms than the CTCA group (29.6% vs 6.8%, p=0.0001) with no significant difference in the rate of revascularisation (73% vs 67%, p=0.72). Mean time from CTCA to angiogram was significantly longer in the Combined group (81.2 vs 38.1 days, p=0.0001). Both sensitivity and specificity were lower in the Combined group than in the CTCA group (sensitivity: 70% vs 93%, specificity: 75% vs 100%). The rate of long term MACE was significantly higher in the Combined group (8.7% vs 2.6%, p=0.0026). Multivariate analysis of CTCA and functional imaging findings found that CTCA-derived four vessel aggregate stenosis score (0–12) was the strongest predictor of MACE for the whole cohort (OR 4.4, p&lt;0.0001), and also for those with negative functional tests (OR 3.9, p&lt;0.0001). Per patient, a combined strategy was more expensive than CTCA alone (£1551 vs £368, p=0.0001). CTCA and functional data vs outcomes Conclusions Combining multi-modality functional testing with CTCA increased costs but did not improve diagnostic accuracy or long term outcomes. Further reductions in both MACE and unnecessary invasive angiography are desirable; CT-derived functional data such as FFRCT may be implicated.

Comprehensive anatomical and functional imaging in patients with type I neurofibromatosis using simultaneous FDG-PET/MRI.

To demonstrate the clinical use of FDG-PET/MRI for monitoring enlargement and metabolism of plexiform neurofibromas (PNF) in patients with neurofibromatosis type 1 (NF1), in whom the development of a malignant peripheral nerve sheath tumor (MPNST) is often a life limiting event. NF1 patients who underwent a simultaneous FDG-PET/MRI examination in our institution from September 2012 to February 2018 were included. Indication was suspicion of malignant transformation of a PNF to MPNST. A maximum of six peripheral nerve lesions per patient were defined as targets. Standardized uptake values (SUV) and apparent diffusion coefficients (ADC) were measured. The presence of target sign and contrast-medium enhancement was visually recorded. Growth rates were estimated comparing prior or follow-up examinations and correlated with FDG uptake and ADC values. The presence of CNS lesions in cerebral T2 weighted images was recorded. In 28 NF1 patients a total number of 83 peripheral nerve tumors, 75 benign PNFs and eight MPNSTs, were selected as target lesions. The SUVs of MPNSTs were significantly higher than the SUVs of PNF (3.84 ± 3.98 [SUVmean MPNSTs] vs. 1.85 ± 1.03 [SUVmean PNF], P < .01). Similarly, lesion SUVmean-to-liver SUVmean ratios significantly differed between MPNSTs and PNF (3.20 ± 2.70 [MPNSTs] vs. 1.23 ± 0.61 [PNF]; P < .01). For differentiation between still benign PNF and MPNSTs, we defined SUVmax ≥ 2.78 as a significant cut-off value. Growth rate of PNF correlated significantly positively with SUVmean (rs = .41; P = .003). MRI parameters like ADCmean (1.87 ± 0.24 × 10-3 mm2/s [PNF] vs. 1.76 ± 0.11 × 10-3 mm2/s [MPNSTs]; P > .05], contrast medium enhancement (P = .50) and target sign (P = .86) did not differ between groups. Simultaneous FDG-PET/MRI is a comprehensive imaging modality for monitoring PNF in NF1 patients. The combined acquisition of both morphologic information in MRI and metabolic information in PET enables the correlation of lesion growth rates with metabolic activity and to define SUV thresholds of significance to identify malignant transformation, which is of utmost clinical significance.

P279Underuse of non-invasive functional imaging in patients at intermediate risk of coronary artery disease. A decision support system in the clinical practice. The ARTICA database

P279Underuse of non-invasive functional imaging in patients at intermediate risk of coronary artery disease. A decision support system in the clinical practice. The ARTICA database

Migraine and Autonomic Dysfunction: Which Is the Horse and Which Is the Jockey?

Symptoms of autonomic dysfunction are common in patients with migraine, both during and between migraine attacks. Studies evaluating objective autonomic testing in patients have found significant, though somewhat conflicting results. The purposes of this review are to summarize and interpret the key findings of these studies, including those evaluating heart rate variability, autonomic reflex testing, and functional imaging in patients with migraine. The neuroanatomy of the central autonomic network as it relates to migraine is also reviewed. Several studies have evaluated autonomic balance in migraineurs, with conflicting results on the magnitude of sympathetic versus parasympathetic dysfunction. Most studies demonstrate sympathetic impairment, with a lesser degree of parasympathetic impairment. Three trends have emerged: (1) migraine with aura tends to produce more significant autonomic dysfunction than migraine without aura, (2) sympathetic impairment is more common than parasympathetic impairment, and (3) sympathetic impairment is common in the interictal period, with increased sympathetic responsiveness during the ictal period, suggesting adrenoreceptor hypersensitivity.

Memory Deficits After Aneurysmal Subarachnoid Hemorrhage: A Functional Magnetic Resonance Imaging Study.

Patients who have sustained aneurysmal subarachnoid hemorrhage (aSAH) are thought to have cognitive impairment. However, little is known about the characteristics of functional imaging in patients with aSAH. In this study, we explored whole brain activity patterns in patients with aSAH using amplitude of low-frequency fluctuation (ALFF) and functional connectivity (FC). Fifty patients with aSAH and 30 healthy controls were recruited and subjected to a resting-state functional magnetic resonance imaging scan and cognitive tasks. Abnormalities of ALFF and FC in patients with aSAH and the correlations with cognitive tasks were assessed. The aSAH group exhibited increased ALFF mainly in the left parahippocampal gyrus (PHG), left inferior temporal gyrus (ITG), and left thalamus (THAL). FC and regression analysis showed positive correlations between functional connectivity strength (FCS) and memory performance in several connections in the aSAH group. These included (1) decreased FC between the left PHG and left inferior parietal lobe; (2) decreased FC between the left ITG and bilateral inferior frontal gyrus orbital part (ORBinf), right middle frontal gyrus; and (3) increased FC between the left THAL and right inferior frontal gyrus orbital part (ORBinf), and right inferior frontal gyrus opercular part. Our findings not only demonstrate the unique abnormal cerebral functional topology of patients with aSAH on both local and network levels, but also confirm the correlation between specific FCS and memory function in these patients. In addition, we have identified several potential imaging biomarkers for predicting cognitive outcomes in patients with aSAH.

A review of the predictive role of functional imaging in patients with mucosal primary head and neck cancer treated with radiation therapy.

Advanced radiotherapy techniques, such as intensity-modulated radiotherapy, have been reported to reduce toxicities by improving the dose conformity in mucosal primary head and neck cancer (MPHNC). However, to further optimize the therapeutic ratio, details on individual patient and disease characteristics may be necessary to tailor treatments. This is likely to include identifying poor responders for treatment intensification and good responders for de-escalation strategies. Non-invasive, repeatable imaging biomarkers are attractive modalities in both pre-treatment and intra-treatment response prediction with a view to individualized treatment options. This review has assessed the current literature on the prognostic/predictive role of widely available functional imaging (FI) studies such as fMRI(functional magnetic resonance imaging), functional computed tomography (fCT) and positron-emission-tomography(PET). A literature search was carried out using Medline, Embase and PubMed. Studies were included if imaging was undertaken pre and/or during radiotherapy (with or without the addition of chemotherapy and/or surgery). A total of 99 relevant studies were identified: 14 fMRI, 10 fCT, 59 FDG-PET and 16 non-FDG-PET studies. These articles were reviewed to identify imaging parameters demonstrating a correlation with patient outcome or a factor considered to impact on patient outcome and thus likely to be of potential predictive value in MPHNC and associated future radiotherapy treatment directions. Several studies have demonstrated that both pre-treatment and mid-treatment FDG-PET is predictive of outcomes. However, further studies are required to confirm the role of other imaging studies including fMRI and PET using other tracers. There is large heterogeneity within and between published studies, including tumour sites, treatment options, outcome endpoints and parameters assessed. We propose a minimum set of factors that should be reported and make recommendations for studies evaluating the predictive utility in MPHNC.

CT imaging of myocardial perfusion: Possibilities and perspectives

Functional imaging in patients with suspected or known coronary artery disease (CAD) is crucial for the identification of patients who could benefit from coronary revascularization. Several studies demonstrated the high diagnostic accuracy of Single-photon-emission computed tomography myocardial perfusion imaging, stress perfusion magnetic resonance imaging, and of invasive FFR measurements for the detection of hemodynamic relevant stenosis. Cardiac computed tomography (CT) used to be limited to coronary angiography (CTA); current guidelines recommend CTA only for the exclusion of CAD. Technological advances now offer the possibility to assess myocardial perfusion by computed tomography (CT-MPI). Though different acquisition protocols and post-processing algorithms still have to be evaluated, initial clinical studies could already show a diagnostic accuracy comparable to the established imaging modalities. Thus, cardiac CT may offer a combined approach of anatomical and functional imaging. Beside the need for further studies, especially on the prognostic value of CT-MPI to stratify future cardiovascular events, the comparatively high radiation exposure and additional administration of contrast agent has to be taken in account.

Neural correlates of recovery from Foix–Chavany–Marie syndrome

Cerebral reorganization during recovery after stroke has been investigated using functional imaging in patients with subcortical motor stroke. The functional correlates of recovery from anarthria, however, are yet unknown. A 48-year-old male patient recovering from complete anarthria after unilateral right-sided subcortical hemorrhagic stroke is described. The main outcome measures included clinical and neuroimaging data at three different time points (at the onset of symptoms, after 6 weeks and after 6 months). At 6 weeks, increased activations in the right and left frontal operculum were found and were followed by a trend towards normalization of the activation pattern at 6 months. These results suggest a role of anterior opercular regions in recovery from anarthria after subcortical stroke. Moreover, complete recovery is possible after such lesions.

WE-E-BRA-03: MR Functional Imaging to Guide Radiotherapy: Opportunities and Challenges in the Clinic.

1. Discuss the clinical use of MR functional imaging in patients receiving radiotherapy and the challenges to wide-spread clinical utilization. 2. Discuss the value of MR functional imaging as a predictor of clinical outcome in patients receiving radiotherapy, and a means of monitoring biologic response over a course of fractionated treatment. 3. Understand the role of MR functional imaging in the evaluation of new treatment strategies comprised of radiotherapy and drugs that specifically target the tumor vasculature.

Performances de la TEP-TDM à la 6-Fluoro-[18F]-L-Dihydroxyphénylalanine (FDOPA) et de l’imagerie radiologique conventionnelle dans la prise en charge des patients avec maladie tumorale endocrine dont le primitif est inconnu

IntroductionDespite the extensive diagnostic work-up performed by conventional morphologic and functional imaging in patients with endocrine metastatic malignancies, the primary tumor remains often unknown. Knowledge of the primary tumor improves patients’ management in case of metastatic disease, and allows curative surgical debulking. At present, few studies have focused on the detection of the primary lesion. AimsTo retrospectively assess the FDOPA PET/CT accuracy in the detection of primary endocrine tumors and to evaluate the incremental value of FDOPA PET/CT over conventional imaging. Patients and methodsFourteen patients with biopsy-proven or clinically and biologically suspected endocrine tumors underwent FDOPA PET/CT. Results were compared with conventional imaging, and related to a pathologic or follow-up gold standard. ResultsFDOPA PET/CT detected the primary tumor in four out of 14 patients. Conventional imaging detected the primary tumor in three out of 14 patients. The association of FDOPA PET/CT and morphologic imaging allowed the identification of five out of 14 primary tumors. On an organ-based analysis, FDOPA PET/CT detected more metastasis than morphologic imaging (respective sensitivities of 92% and 58%). ConclusionIn our study, FDOPA PET/CT seemed more sensitive than conventional imaging for the detection of primary endocrine tumors and metastatic spread assessment. Physiological pancreatic uptake hampers FDOPA PET/CT accuracy for the detection of islet cell primary malignancies. Moreover, some pathologic characteristics of the endocrine phenotype, such as cellular differentiation, may influence FDOPA tumoral uptake.

Periaqueductal Grey Stimulation Induced Panic-Like Behaviour Is Accompanied by Deactivation of the Deep Cerebellar Nuclei

Until recently, the cerebellum was primarily considered to be a structure involved in motor behaviour. New anatomical and clinical evidence has shown that the cerebellum is also involved in higher cognitive functions and non-motor behavioural changes. Functional imaging in patients with anxiety disorders and in cholecystokinin tetrapeptide-induced panic-attacks shows activation changes in the cerebellum. Deep brain stimulation of the dorsolateral periaqueductal grey (dlPAG) and the ventromedial hypothalamus (VMH) in rats has been shown to induce escape behaviour, which mimics a panic attack in humans. We used this animal model to study the neuronal activation in the deep cerebellar nuclei (DCbN) using c-Fos immunohistochemistry. c-Fos expression in the DCbN decreased significantly after inducing escape behaviour by stimulation of the dlPAG and the VMH, indicating that the DCbN were deactivated. This study demonstrates that the DCbN are directly or indirectly involved in panic attacks. We suggest that the cerebellum plays a role in the selection of relevant information, and that deactivation of the cerebellar nuclei is required to allow inappropriate behaviour to occur, such as panic attacks.

Neural correlates of efficacy of voice therapy in Parkinson's disease identified by performance–correlation analysis

LSVT LOUD (Lee Silverman Voice Treatment) is efficacious in the treatment of speech disorders in idiopathic Parkinson's disease (IPD), particularly hypophonia. Functional imaging in patients with IPD has shown abnormalities in several speech regions and changes in these areas immediately following treatment. This study serves to extend the analysis by correlating changes of regional neural activity with the main behavioral change following treatment, namely, increased vocal intensity. Ten IPD participants with hypophonia were studied before and after LSVT LOUD. Cerebral blood flow during rest and reading conditions were measured by H(2)(15)O-positron emission tomography. Z-score images were generated by contrasting reading with rest conditions for pre- and post-LSVT LOUD sessions. Neuronal activity during reading in the pre- versus post-LSVT LOUD contrast was correlated with corresponding change in vocal intensity to generate correlation images. Behaviorally, vocal intensity for speech tasks increased significantly after LSVT LOUD. The contrast and correlation analyses indicate a treatment-dependent shift to the right hemisphere with modification in the speech motor regions as well as in prefrontal and temporal areas. We interpret the modification of activity in these regions to be a top-down effect of LSVT LOUD. The absence of an effect of LSVT LOUD on the basal ganglion supports this argument. Our findings indicate that the therapeutic effect of LSVT LOUD in IPD hypophonia results from a shift in cortical activity to the right hemisphere. These findings demonstrate that the short-term changes in the speech motor and multimodal integration areas can occur in a top-down manner.

Hemichorea associated with gabapentin therapy with hypoperfusion in contralateral basal ganglion - a case of a paraplegic patient with neuropathic pain

Functional imaging in patients with movement disorders has suggested abnormalities of regional cerebral blood flow (rCBF). We describe a patient with thoracic cord lesion with subsequent severe neuropathic pain. Right hemichorea developed and was related to adjunctive therapy with gabapentin. The patient's hemichorea decreased gradually after cessation of gabapentin. The study of rCBF revealed hypoperfusion in the contralateral basal ganglia compared with the previous study of rCBF. Our patient is the first patient with neuropathic pain, treated with gabapentin who developed hemichorea, in the absence of brain lesions. Imaging studies of rCBF showed a perfusion defect in the contralateral basal ganglion.