Background Striatal dopamine deficiency and metabolic changes are well-known phenomena in dementia with Lewy bodies and can be quantified in vivo by I-123-Ioflupane brain single-photon emission computed tomography of dopamine transporter and F-18-fluorodesoxyglucose PET. However, the linkage between both biomarkers is ill-understood. Objective We used the hitherto largest study cohort of combined imaging from the European consortium to elucidate the role of both biomarkers in the pathophysiological course of dementia with Lewy bodies. Methods We compared striatal dopamine deficiency and glucose metabolism of 84 dementia with Lewy body patients and comparable healthy controls. After normalization of data, we tested their correlation by region-of-interest-based and voxel-based methods, controlled for study center, age, sex, education, and current cognitive impairment. Metabolic connectivity was analyzed by inter-region coefficients stratified by dopamine deficiency and compared to healthy controls. Results There was an inverse relationship between striatal dopamine availability and relative glucose hypermetabolism, pronounced in the basal ganglia and in limbic regions. With increasing dopamine deficiency, metabolic connectivity showed strong deteriorations in distinct brain regions implicated in disease symptoms, with greatest disruptions in the basal ganglia and limbic system, coincident with the pattern of relative hypermetabolism. Conclusions Relative glucose hypermetabolism and disturbed metabolic connectivity of limbic and basal ganglia circuits are metabolic correlates of dopamine deficiency in dementia with Lewy bodies. Identification of specific metabolic network alterations in patients with early dopamine deficiency may serve as an additional supporting biomarker for timely diagnosis of dementia with Lewy bodies. (c) 2019 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.

Vulnerability to stress-induced inflammation has been linked to a dysfunctional hypothalamus–pituitary–adrenal (HPA) axis. In the present study, patients with known or suspected coronary artery disease (CAD) were assessed with respect to inflammatory and HPA axis response to acute physical exercise. An exercise stress test was combined with SPECT myocardial perfusion imaging. Plasma and saliva samples were collected before and 30 min after exercise. Interleukin (IL)-6 and adrenocorticotropic hormone (ACTH) were measured in plasma, while cortisol was measured in both plasma and saliva. In total, 124 patients were included of whom 29% had a prior history of CAD and/or a myocardial perfusion deficit. The levels of exercise intensity and duration were comparable in CAD and non-CAD patients. However, in CAD patients, IL-6 increased after exercise (p = 0.019) while no differences were seen in HPA axis variables. Conversely, patients without CAD exhibited increased levels of ACTH (p = 0.003) and cortisol (p = 0.004 in plasma, p = 0.006 in saliva), but no change in IL-6. We conclude that the IL-6 response to acute physical exercise is exaggerated in CAD patients and may be out of balance due to HPA axis hypoactivity. It remains to be further investigated whether this imbalance is a potential diagnostic and therapeutic target in CAD.

INTRODUCTION: We investigated if image- and diagnostic quality in SPECT MPI could be maintained despite a reduced acquisition time adding Depth Dependent Resolution Recovery (DDRR) for image reconstruction. Images were compared with filtered back projection (FBP) and iterative reconstruction using Ordered Subsets Expectation Maximization with (IRAC) and without (IRNC) attenuation correction (AC).

MATERIALS AND METHODS: Stress- and rest imaging for 15 min was performed on 21 subjects with a dual head gamma camera (Infinia Hawkeye; GE Healthcare), ECG-gating with 8 frames/cardiac cycle and a low-dose CT-scan. A 9 min acquisition was generated using five instead of eight gated frames and was reconstructed with DDRR, with (IRACRR) and without AC (IRNCRR) as well as with FBP. Three experienced nuclear medicine specialists visually assessed anonymized images according to eight criteria on a four point scale, three related to image quality and five to diagnostic confidence. Statistical analysis was performed using Visual Grading Regression (VGR).

RESULTS: Observer confidence in statements on image quality was highest for the images that were reconstructed using DDRR (P<0·01 compared to FBP). Iterative reconstruction without DDRR was not superior to FBP. Interobserver variability was significant for statements on image quality (P<0·05) but lower in the diagnostic statements on ischemia and scar. The confidence in assessing ischemia and scar was not different between the reconstruction techniques (P = n.s.).

CONCLUSION: SPECT MPI collected in 9 min, reconstructed with DDRR and AC, produced better image quality than the standard procedure. The observers expressed the highest diagnostic confidence in the DDRR reconstruction.

The aim of the study was to compare the efficacy of olfactory testing and presynaptic dopamine imaging in diagnosing Parkinsons disease (PD) and atypical parkinsonian syndromes (APS); to evaluate if the combination of these two diagnostic tools can improve their diagnostic value. A prospective investigation of 24 PD patients, 16 APS patients and 15 patients with non-parkinsonian syndromes was performed during an 18-month period. Single photon emission computed tomography with the presynaptic radioligand I-123-FP-CIT (DaTSCAN (R)) and olfactory testing with the Brief 12-item Smell Identification Test (B-SIT) were performed in all patients. DaTSCAN was analysed semi-quantitatively, by calculating two different striatal uptake ratios, and visually according to a predefined ranking scale. B-SIT score was significantly lower for PD patients, but not significantly different between APS and non-parkinsonism. The visual assessment of DaTSCAN had higher sensitivity, specificity and diagnostic accuracy compared to olfactory testing. Most PD patients (75 %) had visually predominant dopamine depletion in putamen, while most APS patients (56 %) had visually severe dopamine depletion both in putamen and in caudate nucleus. The combination of DaTSCAN and B-SIT led to a higher rate of correctly classified patients. Olfactory testing can distinguish PD from non-parkinsonism, but not PD from APS or APS from non-parkinsonism. DaTSCAN is more efficient than olfactory testing and can be valuable in differentiating PD from APS. However, combining olfactory testing and DaTSCAN imaging has a higher predictive value than these two methods separately.

Background: Parkinson's disease (PD) is a degenerative disorder characterized by the progressive degeneration of dopamine-containing cells in substantia nigra, and it is the second most common neurodegenerative disorder worldwide. It can be difficult to differentiate between idiopathic PD and Atypical Parkinsonian syndromes (APS). In a high percentage of APS patients, the right diagnosis is not established even during late stages of the disease. Currently there is no specific test to verify PD, especially in the early stages of the disease.

The aim was to verify if 123I-FP-CIT, DaTSCAN ® can differentiate early stages of Parkinson's disease as well as patients with Atypical Parkinsonian syndromes from manifest Parkinson's disease.

Materials and methods: 121 consecutive patients were investigated with 123I-FP-CIT SPECT, during a four year period. All patients were diagnosed according to the established consensus criteria for diagnosis of Parkinson's disease (PD), (n=53), Atypical Parkinsonian syndromes (APS) (n=18). Remaining patients were grouped early PD (before onset the of L-dopa medication), (n=20), and non-PD syndromes (n=30). SPECT images were analysed visually according to a predefined ranking scale of dopaminergic degeneration, distinguishing a posterior-anterior degeneration pattern (egg shape) to a more global and severe degeneration pattern (burst striatum). Striatum ratios were quantitatively analysed with the 3D software, EXINI.

Results: In the group of APS patients the burst striatum pattern was most frequent and found in 61% (11/18 patients). In PD patients the egg shape pattern was dominating, especially in early PD where it was present in 95% (19/20 patients). The sensitivity of burst striatum degeneration pattern was 61% (95%-CI 36-83%), specificity 90% (95%-CI 81-96%). The sensitivity of egg shape pattern was 74% (95%-CI 62-84%), specificity 90% (95%-CI 47-90%). The uptake ratios were reduced in both PD and APS patients and closely related to the image pattern. The lowest putamen/caudate ratio was found in early PD.

Conclusion: In this study we found that in more than half of the patients it was possible to differentiate between PD and APS by visual interpretation only. Similar results were obtained using semi-quantitative uptake ratios, but combining visual assessment with uptake ratios did not add to the discriminating power of DATSCAN ® SPECT in this material

References: Kahraman D, Eggers C, Schicha H, Timmermann L, Schmidt M. Visual assessment of dopaminergic degeneration pattern in 123I-FP-CIT SPECT differentiates patients with atypical parkinsonian syndromes and idiopathic Parkinson's disease. J Neurol. 2012;259:251-60

Objective To verify if I-123-FP-CIT, DaTSCAN (R) can differentiate early stages of Parkinsons disease (PD) as well as patients with Atypical Parkinsonian syndromes (APS) from manifest Parkinsons disease. Methods 128 consecutive patients were investigated with I-123-FP-CIT SPECT during a 4-year period. All patients were diagnosed according to the established consensus criteria for diagnosis of PD (n = 53) and APS (n = 19). Remaining patients were grouped early PD (before onset of L-DOPA medication), (n = 20), vascular PD (n = 6), and non-PD syndromes (n = 30) and SWEDD (n = 1). SPECT images were analyzed visually according to a predefined ranking scale of dopaminergic nerve cell degeneration, distinguishing a posterior-anterior degeneration pattern (egg shape) from a more global and severe degeneration pattern (burst striatum). Striatum uptake ratios were quantitatively analyzed with the 3D software, EXINI. Results In the group of APS patients, the burst striatum pattern was most frequent and found in 61 % (11/18 patients). In PD patients, the egg shape pattern was dominating, especially in early PD where it was present in 95 % (19/20 patients). The positive predictive value for the egg shape pattern to diagnose PD was 92 % in this material (APS and all PD patients) and the specificity 90 % for the burst striatum pattern to exclude APS. The uptake ratios were reduced in both PD and APS patients and closely related to the image ranking. Conclusion In this study, we found that in more than half of the patients it was possible to differentiate between PD and APS by visual interpretation only. Similar results were obtained using semi-quantitative uptake ratios. Combining visual assessment with uptake ratios did not add to the discriminating power of DaTSCAN (R) SPECT in this material.