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  • 1.
    af Bjerkén, Sara
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB). Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Neurovetenskaper.
    Axelsson, Jan
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Larsson, Anne
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Flygare, Carolina
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Remes, Jussi
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Strandberg, Sara
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Eriksson, Linda
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Neurovetenskaper.
    Bäckström, David C.
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Neurovetenskaper.
    Jakobson Mo, Susanna
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Reliability and validity of visual analysis of [18F]FE-PE2I PET/CT in early Parkinsonian disease2023Ingår i: Nuclear medicine communications, ISSN 0143-3636, E-ISSN 1473-5628, Vol. 44, nr 5, s. 397-406Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Objective: [18F]FE-PE2I (FE-PE2I) is a new radiotracer for dopamine transporter (DAT) imaging with PET. The aim of this study was to evaluate the visual interpretation of FE-PE2I images for the diagnosis of idiopathic Parkinsonian syndrome (IPS). The inter-rater variability, sensitivity, specificity, and diagnostic accuracy for visual interpretation of striatal FE-PE2I compared to [123I]FP-CIT (FP-CIT) single-photon emission computed tomography (SPECT) was evaluated.

    Methods: Thirty patients with newly onset parkinsonism and 32 healthy controls with both an FE-PE2I and FP-CIT were included in the study. Four patients had normal DAT imaging, of which three did not fulfil the IPS criteria at the clinical reassessment after 2 years. Six raters evaluated the DAT images blinded to the clinical diagnosis, interpreting the image as being ‘normal’ or ‘pathological’, and assessed the degree of DAT-reduction in the caudate and putamen. The inter-rater agreement was assessed with intra-class correlation and Cronbach’s α. For calculation of sensitivity and specificity, DAT images were defined as correctly classified if categorized as normal or pathological by ≥4/6 raters.

    Results: The overall agreement in visual evaluation of the FE-PE2I- and FP-CIT images was high for the IPS patients (α = 0.960 and 0.898, respectively), but lower in healthy controls (FE-PE2I: α = 0.693, FP-CIT: α = 0.657). Visual interpretation gave high sensitivity (both 0.96) but lower specificity (FE-PE2I: 0.86, FP-CIT: 0.63) with an accuracy of 90% for FE-PE2I and 77% for FP-CIT.

    Conclusion: Visual evaluation of FE-PE2I PET imaging demonstrates high reliability and diagnostic accuracy for IPS.

  • 2.
    Bäckström, David C
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Neurovetenskaper. DeDepartment of Neurology, Yale University, New Haven, CT, USA.
    Granåsen, Gabriel
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Epidemiologi och global hälsa.
    Jakobson Mo, Susanna
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Riklund, Katrine
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Trupp, Miles
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Neurovetenskaper.
    Zetterberg, Henrik
    Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden; Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden; Department of Neurodegenerative Disease and UCL Queen Square Institute of Neurology, London, UK; UK Dementia Research Institute at UCL, London, UK.
    Blennow, Kaj
    Department of Psychiatry and Neurochemistry, Institute of Neuroscience and Physiology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden; Clinical Neurochemistry Laboratory, Sahlgrenska University Hospital, Mölndal, Sweden.
    Forsgren, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Neurovetenskaper.
    Eriksson Domellöf, Magdalena
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Prediction and early biomarkers of cognitive decline in Parkinson disease and atypical parkinsonism: a population-based study2022Ingår i: Brain Communications, E-ISSN 2632-1297, Vol. 4, nr 2Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The progression of cognitive decline is heterogeneous in the three most common idiopathic parkinsonian diseases: Parkinson disease, multiple system atrophy and progressive supranuclear palsy. The causes for this heterogeneity are not fully understood, and there are no validated biomarkers that can accurately identify patients who will develop dementia and when. In this population-based, prospective study, comprehensive neuropsychological testing was performed repeatedly in new-onset, idiopathic parkinsonism. Dementia was diagnosed until 10 years and participants (N = 210) were deeply phenotyped by multimodal clinical, biochemical, genetic and brain imaging measures. At baseline, before the start of dopaminergic treatment, mild cognitive impairment was prevalent in 43.4% of the patients with Parkinson disease, 23.1% of the patients with multiple system atrophy and 77.8% of the patients with progressive supranuclear palsy. Longitudinally, all three diseases had a higher incidence of cognitive decline compared with healthy controls, but the types and severity of cognitive dysfunctions differed. In Parkinson disease, psychomotor speed and attention showed signs of improvement after dopaminergic treatment, while no such improvement was seen in other diseases. The 10-year cumulative probability of dementia was 54% in Parkinson disease and 71% in progressive supranuclear palsy, while there were no cases of dementia in multiple system atrophy. An easy-to-use, multivariable model that predicts the risk of dementia in Parkinson disease within 10 years with high accuracy (area under the curve: 0.86, P < 0.001) was developed. The optimized model adds CSF biomarkers to four easily measurable clinical features at baseline (mild cognitive impairment, olfactory function, motor disease severity and age). The model demonstrates a highly variable but predictable risk of dementia in Parkinson disease, e.g. a 9% risk within 10 years in a patient with normal cognition and CSF amyloid-β42 in the highest tertile, compared with an 85% risk in a patient with mild cognitive impairment and CSF amyloid-β42 in the lowest tertile. Only small or no associations with cognitive decline were found for factors that could be easily modifiable (such as thyroid dysfunction). Risk factors for cognitive decline in multiple system atrophy and progressive supranuclear palsy included signs of systemic inflammation and eye movement abnormalities. The predictive model has high accuracy in Parkinson disease and might be used for the selection of patients into clinical trials or as an aid to improve the prevention of dementia. 

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  • 3.
    Bäckström, David C
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Linder, Jan
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Jakobson Mo, Susanna
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Riklund, Katrine
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Zetterberg, Henrik
    Blennow, Kaj
    Forsgren, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Lenfeldt, Niklas
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Neurofilament concentration in CSF correlates with disease severity, survival and imaging measures of neurodegeneration in incident Parkinson diseaseManuskript (preprint) (Övrigt vetenskapligt)
  • 4.
    Bäckström, David C
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Neurovetenskaper.
    Linder, Jan
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Neurovetenskaper.
    Jakobson Mo, Susanna
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Riklund, Katrine
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Zetterberg, Henrik
    Blennow, Kaj
    Forsgren, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Neurovetenskaper.
    Lenfeldt, Niklas
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Neurovetenskaper.
    NfL as a biomarker for neurodegeneration and survival in Parkinson disease2020Ingår i: Neurology, ISSN 0028-3878, E-ISSN 1526-632X, Vol. 95, nr 7, s. e827-e838Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    OBJECTIVE: To determine whether neurofilament light chain protein in CSF (cNfL), a sensitive biomarker of neuroaxonal damage, reflects disease severity or can predict survival in Parkinson disease (PD).

    METHODS: We investigated whether disease severity, phenotype, or survival in patients with new-onset PD correlates with cNfL concentrations around the time of diagnosis in the population-based New Parkinsonism in Umeå (NYPUM) study cohort (n = 99). A second, larger new-onset PD cohort (n = 194) was used for independent validation. Association of brain pathology with the cNfL concentration was examined with striatal dopamine transporter imaging and repeated diffusion tensor imaging at baseline and 1 and 3 years.

    RESULTS: Higher cNfL in the early phase of PD was associated with greater severity of all cardinal motor symptoms except tremor in both cohorts and with shorter survival and impaired olfaction. cNfL concentrations above the median of 903 ng/L conferred an overall 5.8 times increased hazard of death during follow-up. After adjustment for age and sex, higher cNfL correlated with striatal dopamine transporter uptake deficits and lower fractional anisotropy in diffusion tensor imaging of several axonal tracts.

    CONCLUSIONS: cNfL shows usefulness as a biomarker of disease severity and to predict survival in PD. The present results indicate that the cNfL concentration reflects the intensity of the neurodegenerative process, which could be important in future clinical trials.

    CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that in patients with PD, cNfL concentrations are associated with more severe disease and shorter survival.

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  • 5.
    Bäckström, David
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Eriksson Domellöf, Magdalena
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Granåsen, Gabriel
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Epidemiologi och global hälsa.
    Linder, Jan
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Mayans, Sofia
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk mikrobiologi.
    Elgh, Eva
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi.
    Jakobson Mo, Susanna
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Forsgren, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    PITX3 genotype and risk of dementia in Parkinson's disease: A population-based study2017Ingår i: Journal of the Neurological Sciences, ISSN 0022-510X, E-ISSN 1878-5883, Vol. 381, s. 278-284Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Dementia is a devastating manifestation of Parkinson's disease (PD). This study investigates whether a common polymorphism in the PITX3 gene (rs2281983), which is of importance for the function of dopaminergic neurons, affects the risk of developing dementia in PD and whether it affects dopamine transporter (DAT) uptake. We PITX3 genotyped 133 patients with new-onset, idiopathic PD, participating in a population-based study in Sweden. Patients were followed prospectively during 6-11 years with extensive investigations, including neuropsychology and DAT-imaging with I-123 FP-CIT. The primary outcome was the incidence of PD dementia (PDD), diagnosed according to published criteria, studied by the Kaplan-Meier method and Cox proportional hazards. Performance in individual cognitive domains, the incidence of visual hallucinations, disease progression and striatal DAT uptake on imaging was also investigated. PD patients carrying the PITX3 C allele had an increased risk of developing PDD (hazard ratio: 2.87, 95% CI: 1.42-5.81, p = 0.003), compared to the PD patients homozygous for the T-allele. Furthermore, the PITX3 C allele carriers with PD had a poorer cognitive performance in the visuospatial domain (p < 0.001) and a higher incidence of visual hallucinations. A trend towards a lower striatal DAT uptake in the PITX3 C allele carriers was suggested, but could not be confirmed. Our results show that a common polymorphism in the PITX3 gene affects the risk of developing PDD and visuospatial dysfunction in idiopathic PD. If validated, these findings can provide new insights into the neurobiology and genetics of non-motor symptoms in PD.

  • 6.
    Bäckström, David
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Granåsen, Gabriel
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Epidemiologi och global hälsa.
    Eriksson Domellöf, Magdalenax
    Umeå universitet, Samhällsvetenskapliga fakulteten, Institutionen för psykologi. Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Linder, Jan
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Jakobson Mo, Susanna
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Riklund, Katrine
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Zetterberg, Henrik
    Blennow, Kaj
    Forsgren, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Early predictors of mortality in parkinsonism and Parkinson disease: A population-based study2018Ingår i: Neurology, ISSN 0028-3878, E-ISSN 1526-632X, Vol. 91, nr 22, s. E2045-E2056Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Objective To examine mortality and associated risk factors, including possible effects of mild cognitive impairment, imaging, and CSF abnormalities, in a community-based population with incident parkinsonism and Parkinson disease. Methods One hundred eighty-two patients with new-onset, idiopathic parkinsonism were diagnosed from January 2004 through April 2009, in a catchment area of 142,000 inhabitants in Sweden. Patients were comprehensively investigated according to a multimodal research protocol and followed prospectively for up to 13.5 years. A total of 109 patients died. Mortality rates in the general Swedish population were used to calculate standardized mortality ratio and expected survival, and Cox proportional hazard models were used to investigate independent predictors of mortality. Results The standardized mortality ratio for all patients was 1.84 (95% confidence interval 1.50-2.22, p < 0.001). Patients with atypical parkinsonism (multiple system atrophy or progressive supranuclear palsy) had the highest mortality. In early Parkinson disease, a mild cognitive impairment diagnosis, freezing of gait, hyposmia, reduced dopamine transporter activity in the caudate, and elevated leukocytes in the CSF were significantly associated with shorter survival. Conclusion Although patients presenting with idiopathic parkinsonism have reduced survival, the survival is highly dependent on the type and characteristics of the parkinsonian disorder. Patients with Parkinson disease presenting with normal cognitive function seem to have a largely normal life expectancy. The finding of a subtle CSF leukocytosis in patients with Parkinson disease with short survival may have clinical implications.

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  • 7.
    Ekman, Urban
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB), Fysiologi. Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI). Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Eriksson, Johan
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB), Fysiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Forsgren, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Jakobson Mo, Susanna
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Riklund, Katrine
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Nyberg, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB), Fysiologi. Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Functional brain activity and presynaptic dopamine uptake in patients with Parkinson's disease and mild cognitive impairment: a cross-sectional study2012Ingår i: Lancet Neurology, ISSN 1474-4422, E-ISSN 1474-4465, Vol. 11, nr 8, s. 679-687Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Many patients with Parkinson's disease have mild cognitive impairment (MCI). Deficits in executive functions and working memory suggest dysfunctional frontostriatal brain circuitry. We aimed to assess brain responses during a working memory task in a cohort of newly diagnosed drug-naive patients with Parkinson's disease with and without MCI.

    Methods: Participants were recruited within a prospective cohort study of incident patients with idiopathic parkinsonism, including Parkinson's disease. Between Jan 1, 2004, and April 30, 2009, all physicians in the Umea catchment area were requested to refer all individuals with suspected parkinsonism to the Department of Neurology at lima University. Included patients fulfilled the UK Parkinson's Disease Society Brain Bank clinical diagnostic criteria for Parkinson's disease. Control individuals were matched on the basis of age and sex with the first 50 patients included in the study. Participants who scored 1.5 SDs or more below the population mean on at least two cognitive measures were diagnosed with MCI. The primary outcome measures were functional MRI blood-oxygen-level-dependent signal and SPECT presynaptic uptake. Functional MRI was done during a verbal two-back working memory task. Presynaptic dopamine SPECT was done to assess presynaptic striatal dopaminergic system integrity. Event-related transient analyses of functional MRI data were done for the whole brain and for frontostriatal regions of interest, and semi-quantitative SPECT analyses were done for striatal regions of interest.

    Findings: Compared with controls (n=24), patients with Parkinson's disease (n=77) had under-recruitment in an extensive brain network including bilateral striatal and frontal regions (p<0.001). Within the Parkinson's disease group, patients with Parkinson's disease and MCI (n=30) had additional under-recruitment in the right dorsal caudate nucleus (p=0.005) and the bilateral anterior cingulate cortex (p<0.001) compared with patients with Parkinson's disease without MCI (n=26). In patients with Parkinson's disease and MCI, SPECT uptake in the right caudate was lower than in patients with Parkinson's disease without MCI (p=0.008) and correlated with striatal functional MRI blood-oxygen-level-dependent signal (r=0.32, p=0.031).

    Interpretation: These altered brain responses in patients with Parkinson's disease and MCI suggest that cognitive impairment is linked to frontostriatal dysfunction.

  • 8.
    Flygare, Lennart
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Al-Ubaedi, Amal
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Öhman, Wilhelm
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Department of Surgery, Skellefteå Hospital, Skellefteå, Sweden.
    Jakobson Mo, Susanna
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Distant metastases and synchronous malignancies on FDG-PET/CT in patients with head and neck cancer: a retrospective study2020Ingår i: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 61, nr 9, s. 1196-1204Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) has been proven to be a good method to detect distant spread of head and neck cancer (HNC). However, most prior studies are based on Asian populations and may not be directly transferable to western populations.

    Purpose: To investigate the frequency and distribution of distant metastases and synchronous malignancies detected by PET/CT in HNC in a northern Swedish population.

    Material and Methods: All primary whole-body FDG-PET/CT examinations performed on the suspicion of HNC (n = 524 patients) between 1 January 2013 and 31 December 2016 at Umeå University Hospital in Sweden were retrospectively reviewed . After the exclusion of 189 examinations without evidence of primary HNC, 335 examinations were analyzed.

    Results: Distant metastases were detected in 10 (3%) patients, all with advanced primary tumors corresponding to TNM stage 3–4, most frequently in salivary gland adenocarcinoma, where 50% of patients had distant spread. Four patients had metastases below the diaphragm, representing 20% of the salivary gland malignancies. In the remaining six patients, metastases were supraphrenic, of which all but one were identified by CT alone. Synchronous malignancies were discovered in 14 (4.2%) patients, of which five were below the diaphragm.

    Conclusion: The overall frequency of distant spread and synchronous malignancy in primary HNC was generally low. However, the risk for distant metastases below the diaphragm was relatively higher in salivary gland adenocarcinoma, supporting whole-body FDG-PET/CT in the primary diagnostic work-up in these patients.

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  • 9.
    Jakobson Mo, Susanna
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Nuclear medicine methods in idiopathic Parkinsonism: pre- and postsynaptic dopamine SPECT2013Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Background: Single photon emission computed tomography (SPECT) with dopamine transporter (DAT) and dopamine D2 receptor (D2R) ligands can visualise the integrity of the nigrostriatal dopamine system. Parkinson’s disease (PD) and the atypical parkinsonian diseases (APD), progressive supranuclear palsy (PSP) and multiple system atrophy (MSA), have similar symptoms and dopamine depletion, but differ in pharmacological response and prognosis. Clinical differentiation between PD and APD is often difficult in the early stages. The aims of the thesis were to evaluate the differential diagnostic and prognostic value of SPECT in early PD, MSA and PSP, to map the pattern of progression with dopamine SPECT, and map the pattern of dopamine SPECT in non-affected elderly volunteers with a prospective approach. Also, we evaluated the methodological aspects of dopamine SPECT with respect to image evaluation tools, reconstruction parameters and gamma cameras.

    Methods: 172 patients, included in an on-going clinical prospective study on idiopathic parkinsonism, participated in the SPECT study. Also, 31 age-matched healthy controls (HC) were followed within this study. SPECT was done with 123I-FP-Cit (DAT SPECT) and 123I-IBZM (D2R SPECT). Regions of interest (ROI) were used as a standard method for semi-quantitative image analysis.

    Results: SPECT uptake ratios from different gamma cameras could be equalised through correction equations derived from images of a brain-like phantom, provided that attenuation correction was applied. The ROI method had high reproducibility. SPECT uptake  in HC, measured with the ROI method and a volume based (VOI) method rendered similar trends, but gender and age differences in SPECT uptake were more marked with the VOI method, and less pronounced in DAT SPECT compared to D2R SPECT with both methods. The DAT SPECT uptake was significantly reduced in very early disease stage of PD and APD compared to HC. DATSPECT uptake was more reduced in PD with postural and gait disturbance (PIGD) compared to tremor-dominant PD. Decline in DAT SPECT uptake during the first year was more pronounced in PD and PSP compared to HC. D2R SPECT uptake overlapped between untreated PD and APD. After initiated treatment, the D2R SPECT uptake was significantly higher in MSA patients compared to PD, PSP and HC. Decline in D2R SPECT uptake during the first year was not significantly different between patients or compared to HC.

    Conclusions: 123I-FP-Cit SPECT is a valuable and sensitive method to detect early stage idiopathic parkinsonism. A different level of uptake between PIGD-PD compared to TD-PD indicates a prognostic potential. It is not possible to differ between PD, MSA and PSP in early stage with 123I-FP-Cit SPECT and no differential diagnostic value was found using 123I-IBZM SPECT in the early, untreated stage of PD, MSA and PSP. A different pattern of uptake of this ligand in MSA compared to PD and PSP during the first years of L-dopa treatment may, however, indicate a diagnostic value during the follow-up period.

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  • 10.
    Jakobson Mo, Susanna
    et al.
    Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI). Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Axelsson, Jan
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    J. Stiernman, Lars
    Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI). Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB).
    Larsson, Anne
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    af Bjerkén, Sara
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB). Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Neurovetenskaper.
    Bäckström, David C.
    Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Neurovetenskaper.
    Gabrielsson Kellgren, Therese
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Avdelningen för medicin.
    Varrone, Andrea
    Department of Clinical Neuroscience, Centre for Psychiatry Research, Karolinska Institutet and Stockholm Health Care Services, Stockholm, Sweden.
    Riklund, Katrine
    Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI). Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    VNTR polymorphism in the SLC6A3 gene does not influence dopamine transporter availability measured by [18F]FE-PE2I PET or [123I]FP-Cit SPECT2022Ingår i: Nuclear medicine communications, ISSN 0143-3636, E-ISSN 1473-5628, Vol. 43, nr 3, s. 247-255Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    OBJECTIVE: To investigate the potential impact of polymorphism in the 3'-untranslated region (3'UTR) of the SLC6A3 gene (DAT1) on normal variation in dopamine transporter (DAT) imaging with [18F]FE-PE2I PET and [123I]FP-Cit SPECT.

    METHODS: Thirty-six individuals (mean age 70.4±5.4 years) with normal [18F]FE-PE2I PET and [123I]FP-Cit SPECT were genotyped for variable number of tandem repeats (VNTR) in the 3′UTR of the DAT1 gene. The DAT-availability in the caudate and putamen as measured with [18F]FE-PE2I PET and [123I]FP-Cit SPECT, as well as in the substantia nigra with [18F]FE-PE2I PET were compared between the participants carrying one or two 9-repeat alleles (i.e. 9R+10R or 9R+9R; 47%) and the participants without a 9R allele (i.e. 10R+10R or 10R+11R; 53%). Nonparametric tests, linear regression analysis and mixed model analysis were used to assess any statistical difference in measured DAT availability between the two allele groups.

    RESULTS: The measured DAT-availability in PET- and SPECT-imaging tended to be slightly higher in the 9R-group; however, the difference did not reach statistical significance in either the caudate or the putamen or the substantia nigra. Instead, age did have a significant effect on the DAT level (P < 0.05) notwithstanding the genotype.

    CONCLUSION: No significant effect of DAT1-genotype was detectable in imaging with [18F]FE-PE2I PET or [123I]FP-Cit, instead, age accounted for the normal variation in DAT-PET and DAT-SPECT.

  • 11.
    Jakobson Mo, Susanna
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI). Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Axelsson, Jan
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Jonasson, Lars
    Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI). Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB).
    Larsson, Anne
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Ögren, Mattias J.
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Ögren, Margareta
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Varrone, Andrea
    Eriksson, Linda
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Bäckström, David
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    af Bjerkén, Sara
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB). Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Linder, Jan
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Riklund, Katrine
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Dopamine transporter imaging with [18F]FE-PE2I PET and [123I]FP-CIT SPECT – a clinical comparison2018Ingår i: EJNMMI Research, E-ISSN 2191-219X, Vol. 8, artikel-id 100Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Dopamine transporter (DAT) imaging may be of diagnostic value in patients with clinically suspected parkinsonian disease. The purpose of this study was to compare the diagnostic performance of DAT imaging with positron emission computed tomography (PET), using the recently developed, highly DAT-selective radiopharmaceutical [18F]FE-PE2I (FE-PE2I), to the commercially available and frequently used method with [123I]FP-CIT (FP-CIT) single-photon emission computed tomography (SPECT) in early-stage idiopathic parkinsonian syndrome (PS).

    Methods: Twenty-two patients with a clinical de novo diagnosis of PS and 28 healthy controls (HC) participating in an on-going clinical trial of FE-PE2I were analyzed in this study. Within the trial protocol, participants are clinically reassessed 2 years after inclusion. A commercially available software was used for automatic calculation of FP-CIT-specific uptake ratio (SUR). MRI-based volumes of interest combined with threshold PET segmentation were used for FE-PE2I binding potential relative to non-displaceable binding (BPND) quantification and specific uptake value ratios (SUVR).

    Results: PET with FE-PE2I revealed significant differences between patients with a clinical de novo diagnosis of PS and healthy controls in striatal DAT availability (p < 0.001), with excellent accuracy of predicting dopaminergic deficit in early-stage PS. The effect sizes were calculated for FE-PE2I BPND (Glass’s Δ = 2.95), FE-PE2I SUVR (Glass’s Δ = 2.57), and FP-CIT SUR (Glass’s Δ = 2.29). The intraclass correlation (ICC) between FE-PE2I BPND FP-CIT SUR was high in the caudate (ICC = 0.923), putamen (ICC = 0.922), and striatum (ICC = 0.946), p < 0.001. Five of the 22 patients displayed preserved striatal DAT availability in the striatum with both methods. At follow-up, a non-PS clinical diagnosis was confirmed in three of these, while one was clinically diagnosed with corticobasal syndrome. In these patients, FE-PE2I binding was also normal in the substantia nigra (SN), while significantly reduced in the remaining patients. FE-PE2I measurement of the mean DAT availability in the putamen was strongly correlated with BPND in the SN (R = 0.816, p < 0.001). Olfaction and mean putamen DAT availability was correlated using both FE-PE2I BPND and FP-CIT SUR (R ≥ 0.616, p < 0.001).

    Conclusion: DAT imaging with FE-PE2I PET yields excellent basic diagnostic differentiation in early-stage PS, at least as good as FP-CIT SPECT.

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  • 12.
    Jakobson Mo, Susanna
    et al.
    Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI). Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Axelsson, Jan
    Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI). Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Jonasson, Lars S.
    Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI). Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB).
    Riklund, Katrine
    Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI). Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Validation of dynamic [18F]FE-PE2I PET for estimation of relative regional cerebral blood flow: a comparison with [15O]H2O PET2022Ingår i: EJNMMI Research, E-ISSN 2191-219X, Vol. 12, nr 1, artikel-id 72Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Dopamine transporter (DAT) imaging is used in the diagnostic work-up in suspected parkinsonian syndromes and dementia with Lewy bodies but cannot differentiate between these syndromes, and an extra brain imaging examination of the regional cerebral blood flow (rCBF) or glucose metabolism is often needed for differential diagnosis. The requirement of two different imaging examinations is resource-consuming and inconvenient for the patients. Therefore, imaging of both cortical blood flow and DAT imaging with the same radiotracer would be more convenient and cost-effective. The aim of this study was to test whether relative regional cerebral blood flow (rCBFR) can be measured with the DAT-specific positron emission tomography (PET) tracer [18F]FE-PE2I (FE-PE2I), by validation with cerebral perfusion measured with [15O]H2O PET (H2O).

    Methods: The rCBFR was quantified by kinetic modeling for FE-PE2I (R1) and H2O (F). The R1 was calculated using the simplified reference tissue model, and F was calculated with a modified Koopman double-integration method. The linear relationship and intraclass correlation (ICC) between R1 and F were tested in image data derived from 29 patients with recent onset parkinsonism and 30 healthy controls.

    Results: There was a strong linear correlation across all subjects between R1 and F in the frontal, parietal, temporal, cingulate and occipital cortex as well as in the striatum (r ≥ 0.731–0.905, p < 0.001) with a good-to-excellent ICC, ranging from 0.727 to 0.943 (p < 0.001).

    Conclusions: Our results suggest that FE-PE2I may be used as a proxy for cerebral perfusion, thus potentially serving as a radiotracer for assessment of both DAT availability and rCBFR in one single dynamic scan. This could be valuable in the differential diagnosis of parkinsonian syndromes.

    Trial registration: EUDRA-CT 2015-003045-26. Registered 23 October 2015 https://www.clinicaltrialsregister.eu/ctr-search/search?query=2015-003045-26

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  • 13.
    Jakobson Mo, Susanna
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Larsson, Anne
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Johansson, Lennart
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Stenlund, Hans
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Epidemiologi och global hälsa.
    Forsgren, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Riklund, Katrine
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Cross-camera comparison of ROI-based semi-quantitative 123I-IBZM SPECT data in healthy volunteers using an anthropomorphic phantom for calibration2013Ingår i: Acta Radiologica, ISSN 0284-1851, E-ISSN 1600-0455, Vol. 54, nr 5, s. 549-556Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background In (123)I-Iolopride (IBZM) SPECT reference values may diverge between camera systems. If multicenter pooling of normal material databases is needed, differences in measured semi-quantitative data due to equipment performance and reconstruction parameters have to be investigated in each instance to determine the comparability.

    Purpose To explore the differences in (123)I-IBZM measured uptake ratios between two different gamma cameras in healthy controls, the intra-rater reproducibility of the image evaluation method and the possibility to equalize uptake ratios by calibration through an anthropomorphic phantom.

    Material and Methods Differences in ROI-based semi-quantitative data from two different gamma camera systems, the three-headed brain dedicated Neurocam and the two-headed multipurpose hybrid system Infinia Hawkeye, were studied using image data from a group of healthy volunteers and an anthropomorphic brain-phantom scanned with both cameras. Several reconstruction methods and corrections were applied. To test the reliability of the ROI method, the intra-observer reproducibility was determined for the ROI method in this study.

    Results The ROI method had a high reliability. Differences in mean measured uptake (123)I-IBZM ratios in healthy controls varied between 2.9% and 6.5% depending on reconstruction and correction for attenuation and scatter. After calibration, the differences decreased. There were no statistically significant differences between corrected ratios from the two camera systems in the study when images were reconstructed with attenuation correction.

    Conclusion The conformity of uptake ratios in attenuation corrected (123)I-IBZM images derived from the two different cameras was improved by using an anthropomorphic phantom for calibration.

  • 14.
    Jakobson Mo, Susanna
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Larsson, Anne
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Linder, Jan
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Birgander, Richard
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Edenbandt, Lars
    Göteborgs Universitet, Avdelningen för molekylär och klinisk medicin.
    Stenlund, Hans
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Epidemiologi och global hälsa.
    Forsgren, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Riklund, Katrine
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    123I-FP-Cit and 123I-IBZM SPECT uptake in a prospective normal material analysed with two different semi-quantitative image evaluation tools2013Ingår i: Nuclear medicine communications, ISSN 0143-3636, E-ISSN 1473-5628, Vol. 34, nr 10, s. 978-989Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Objective: The need for age-adjusted and/or sex-adjusted reference values in dopamine transporter (DAT) and dopamine D2 receptor (D2R) imaging with single-photon emission computed tomography (SPECT) in a longitudinal study of parkinsonian diseases was investigated. We used two different image evaluation tools with a cross-sectional and longitudinal statistical approach.

    Materials and methods: Baseline DAT and/or D2R SPECT were performed in 51 healthy controls (HC), age-matched to patients in an ongoing prospective study on idiopathic parkinsonism. Twenty-four HC were re-examined after 3 years and 21 HC were examined again after 5 years. SPECT was performed with I-123-FP-Cit and I-123-IBZM on a two-headed hybrid gamma camera. Regions of interest and volumes of interest (VOIs) were used for image evaluation. A cross-sectional and longitudinal statistical analysis was carried out.

    Results: Fewer sex-based differences and less age dependency were seen in DAT SPECT uptake ratios compared with D2R SPECT uptake ratios and when comparing uptake ratios obtained with regions of interest against those with VOIs. In the cross-sectional analysis, a significant age-dependent decline was seen in women in both DAT and D2R uptakes with the VOI method but not in men with either evaluation method. In the longitudinal dataset, both a slight decline and increase over time were seen in DAT uptake; however, a general pattern of decrease was seen in both men and women in D2R uptake.

    Conclusion: The choice of the image evaluation method can influence the pattern of sex-based and age-related differences. The results speak for the use of age-stratified reference values for women, in particular when using a VOI method.

  • 15.
    Jakobson Mo, Susanna
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Linder, Jan
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Blomstedt, Patric
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Granåsen, Gabriel
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Epidemiologi och global hälsa.
    Forsgren, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Hariz, Marwan
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap. Unit of Functional Neurosurgery, UCL Institute of Neurology, London, UK.
    Long-term dopamine transporter imaging in Parkinson's disease treated with zona incerta stimulation2016Ingår i: Nuclear medicine communications, ISSN 0143-3636, E-ISSN 1473-5628, Vol. 37, nr 5, s. 499-508Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Objective: The caudal zona incerta (cZI) is a promising, clinically beneficial target for deep brain stimulation (DBS) in Parkinson’s disease (PD). To assess whether DBS of the cZI affects the rate of dopamine terminal dysfunction, PD patients with and without DBS were followed prospectively with 123I FP-Cit single photon emission tomography from the first diagnosis and up to 8 years.

    Methods: Six patients underwent DBS of the cZI during the survey period. Twenty-two PD patients only on pharmacotherapy served as controls. 123I FP-Cit and clinical assessment were performed at baseline and after 1, 3 and 5 years in all patients. Ten patients also underwent a 123I FP-Cit after 8 years. Image data were evaluated semiquantitatively. Mixed-model analysis was used to assess the relative change in 123I FP-Cit uptake and comparison between surgically and conservatively treated PD patients.

    Results: The relative decrease in 123I FP-Cit uptake was more pronounced in DBS-treated patients than in controls in the more affected caudate (P=0.037) and putamen (P=0.013). The annual decrease rates were higher in the less affected than the more affected putamen, and were slightly greater in DBS-treated patients (4.8%, 95%confidence interval: 8.5–2.2%) than in controls (4.0%, 95% confidence interval: 5.1–3.1%).

    Conclusion: This long-term prospective study confirms that the underlying dopaminergic dysfunction continues despite clinical improvement in PD patients with DBS of the cZI. A slightly faster rate of decrease in 123I FP-Cit uptake in these patients compared with conservatively treated PD patients may reflect a more aggressive form of PD.

  • 16.
    Jakobson Mo, Susanna
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Linder, Jan
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Forsgren, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Holmberg, Henrik
    Umeå universitet, Samhällsvetenskapliga fakulteten, Handelshögskolan vid Umeå universitet, Statistik.
    Larsson, Anne
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Riklund, Katrine
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Pre- and postsynaptic dopamine SPECT in idiopathic parkinsonian diseases: a follow-up study2013Ingår i: BioMed Research International, ISSN 2314-6141, Vol. 2013, s. 143532-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We prospectively evaluated the diagnostic contribution of 123I-FP-Cit (DAT) and 123I-IBZM (IBZM) SPECT in 29 patients with Parkinson’s disease (PD) (74.4 ± 4.2 years) and 28 patients with atypical parkinsonian diseases (APD) (74.3 ± 9.2 years). Twelve had multiple system atrophy (MSA) and 16 progressive supranuclear palsy (PSP). Sixteen age-matched healthy controls (HC) were included. DAT and IBZM SPECTs were made at baseline and after 1 year in all PD patients and in 20 (DAT) and 18 (IBZM) of the APD patients, and after 3 years in 22 (DAT) and 17 (IBZM) of the PD patients and in 10 (DAT) and 10 (IBZM) of the APD patients. The relative DAT uptake decrease was faster in PD and PSP than in HC and MSA. In PSP the DAT uptake was lower than in MSA after 1 year but not after 3 years. Baseline IBZM uptake was not significantly different between patients and HC or between PD and APD. One year after initiated dopaminergic treatment the mean IBZM uptake in the MSA patients remained high compared to PSP and after 3 years compared to PD, PSP, and HC.Thus, the pattern of uptake of these ligands over time may be of value in discriminating between these diagnoses.

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    Pre- and postsynaptic dopamine SPECT in idiopathic parkinsonian diseases: a follow-up study
  • 17.
    Jakobson Mo, Susanna
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Linder, Jan
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Neurologi.
    Forsgren, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Neurologi.
    Larsson, Anne
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Johansson, Lennart
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Riklund, Katrine
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Pre- and postsynaptic dopamine SPECT in the early phase of idiopathic parkinsonism: a population-based study2010Ingår i: European Journal of Nuclear Medicine and Molecular Imaging, ISSN 1619-7070, E-ISSN 1619-7089, Vol. 37, nr 11, s. 2154-2164Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    PURPOSE: The aim of this study was to assess the diagnostic contribution of pre- and postsynaptic dopamine SPECT in drug-naïve patients with early idiopathic parkinsonism and to investigate possible differences between idiopathic Parkinson's disease (PD) and atypical parkinsonian syndromes (APS) and possible differences in motor subtypes of parkinsonism.

    METHODS: A group of 128 newly diagnosed idiopathic parkinsonian patients and 48 healthy controls was studied. Presynaptic baseline SPECT with (123)I-FP-CIT was performed in all patients and in 120 patients also a baseline postsynaptic SPECT with (123)I-IBZM. Clinical diagnoses were reassessed after 12 months.

    RESULTS: Presynaptic uptake in the putamen and caudate was significantly reduced in patients compared to controls. Presynaptic uptake ratios were not different between PD patients and patients with APS, and postsynaptic uptake in APS was not significantly reduced compared to PD or controls. In half of the APS patients both pre- and postsynaptic uptake ratios were reduced on the same side in the striatum. Impaired motor performance was associated with decreased presynaptic uptake in the putamen in PD. The postural instability and gait difficulty (PIGD) subtype of PD had lower presynaptic uptake ratios than patients with tremor-dominated (TD) symptoms.

    CONCLUSION: Not only presynaptic putamen uptake ratios, but also caudate ratios were reduced in a majority of the patients in our study. At baseline scan, i.e. in an early stage of the disease, the accuracy of excluding APS in the whole study population was 85% using a combination of pre- and postsynaptic SPECT. Already at baseline, lower presynaptic SPECT ratios were seen in PD with PIGD at onset compared to those with TD subtype.

  • 18.
    Jakobson Mo, Susanna
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Linder, Jan
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Forsgren, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Riklund, Katrine
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Accuracy of Visual Assessment of Dopamine Transporter Imaging in Early Parkinsonism2015Ingår i: Movement Disorders Clinical Practice, E-ISSN 2330-1619, Vol. 2, nr 1, s. 17-23Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Dopamine transporter (DaT) imaging may be supportive in the initial clinical diagnostic workup in patients with suspected parkinsonian diseases, given that the method has the potential to detect dopaminergic degeneration. We investigated the diagnostic accuracy of visual assessment of the initial DaT single-photon emission CT (DaT-SPECT) with 123I-FP-CIT in a large group of early-stage parkinsonian patients. After inclusion in a long-term multidisciplinary population-based prospective study, a baseline DaT-SPECT was done in 171 incidental, L-dopa-naïve, parkinsonian patients (102 men and 69 women) and 37 healthy controls (19 men and 18 women). The results of the DaT-SPECTs were linked to criteria-based clinical diagnoses, which were set after a mean follow-up of 4.6 (±1.7) years. The outcome of the visual assessment was also compared with that of a semiquantitative evaluation method using regions of interest to measure uptake ratios in the caudate and putamen. We found that visual assessment of DaT-SPECT in clinically diagnosed incidental Parkinson's disease patients had a sensitivity of 94% and a specificity of 92%, rendering a positive likelihood ratio of 11.75 and a negative likelihood ratio of 0.07. The proportion of false positives was 1.4% and false negatives 4.8% at baseline. These figures were comparable to those of the semiquantitative method. This study demonstrates that visual interpretation of presynaptic dopamine imaging with 123I-FP-CIT offers reliable support in the diagnostic procedure of early parkinsonian diseases.

  • 19.
    Larsson, Anne
    et al.
    Umeå universitet, Medicinsk fakultet, Strålningsvetenskaper, Radiofysik.
    Jakobson Mo, Susanna
    Umeå universitet, Medicinsk fakultet, Strålningsvetenskaper, Diagnostisk radiologi.
    Ljungberg, Michael
    Riklund, Katrine
    Umeå universitet, Medicinsk fakultet, Strålningsvetenskaper, Diagnostisk radiologi.
    Dopamine D2 receptor SPECT with (123)I-IBZM: evaluation of collimator and post-filtering when using model-based compensation-a Monte Carlo study.2010Ingår i: Physics in Medicine and Biology, ISSN 0031-9155, E-ISSN 1361-6560, Vol. 55, nr 7, s. 1971-1988Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In (123)I-IBZM brain SPECT, the main interest is the activity uptake in the striatum relative to the background, and semi-quantitative techniques using regions of interest are typically used for this purpose. Uncertainties in the measured uptakes can however be a problem due to low contrasts and high noise levels. Like SPECT in general, IBZM SPECT should benefit from reconstruction methods that include model-based compensation, but it is important that image acquisition is optimized for this technique. An important factor is the choice of collimator. In this study we compare four different parallel-hole collimators for IBZM SPECT regarding overall quantitative accuracy and measured uptake ratio as a function of image noise and uncertainty. The collimators are low-energy high-resolution (LEHR), low-energy general-purpose (LEGP), extended LEGP (ELEGP) and medium-energy general-purpose (MEGP). The effect of three Butterworth post-filters with cut-off frequencies of 0.3, 0.45 and 0.6 cm(-1) (power factor 8) is also studied. All raw-data projections are produced using Monte Carlo simulations. Of the investigated collimators, the one that is most sensitive to the primary photons, ELEGP, proved to be the most optimal for realistic noise levels. Butterworth post-filtering is advantageous, and the cut-off frequency 0.45 cm(-1) was the best compromise in this study.

  • 20.
    Larsson, Anne
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Jakobson Mo, Susanna
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Riklund, Katrine
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Rotation radius dependence of 123I-FP-CIT and 123I-IBZM SPECT uptake ratios: a Monte Carlo study2012Ingår i: Journal of Nuclear Medicine Technology, ISSN 0091-4916, E-ISSN 1535-5675, Vol. 40, nr 4, s. 249-254Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In dopamine brain SPECT, semiquantitative techniques are in use, mostly for research purposes, to calculate activity uptake in the striatum relative to the background. The measured uptake ratios depend on both acquisition and reconstruction, and one important parameter is the rotation radius of the γ-camera detectors, which affects spatial resolution. In brain SPECT research studies, the rotation radius is typically set to a constant value to maintain a constant resolution, but because of variations in patient anatomy and compliance, this is not always possible.

    METHODS: In this study, correction factors as a function of rotation radius are developed to correct the uptake ratios where the rotation radius has deviated from the reference value, 15 cm. Monte Carlo simulations of a digital brain phantom were used to produce images with a high and a low uptake ratio, and for both studies the rotation radius was varied between 14 and 23 cm. Two different methods, one based on 2-dimensional (2D) regions of interest of constant shape and size, and one based on predefined 3-dimensional (3D) volumes of interest, were used to calculate the semiquantitative uptake ratios.

    RESULTS: For the 2D method, the change in uptake ratio was 1.2%/cm for the high uptake ratio and 0.9%/cm for the low uptake ratio. The corresponding results for the 3D method were 2.1% and 1.7%, respectively.

    CONCLUSION: The 3D method was found to be more dependent on rotation radius than the 2D method, which was expected because of the 3D nature of the partial-volume effect. The correction factors were, however, less dependent on which of the 2 uptake ratios was simulated, which is positive for the application of the correction equations on patient data.

  • 21.
    Larsson, Anne
    et al.
    Umeå universitet, Medicinsk fakultet, Strålningsvetenskaper, Radiofysik.
    Jakobson Mo, Susanna
    Umeå universitet, Medicinsk fakultet, Strålningsvetenskaper, Diagnostisk radiologi.
    Sundström, Torbjörn
    Umeå universitet, Medicinsk fakultet, Strålningsvetenskaper, Diagnostisk radiologi.
    Riklund, Katrine
    Umeå universitet, Medicinsk fakultet, Strålningsvetenskaper, Diagnostisk radiologi.
    Gaussian prefiltering of 123-I DAT SPECT images when using depth-independent resolution recovery.2007Ingår i: Phys Med Biol, ISSN 0031-9155, Vol. 52, nr 18, s. N393-N399Artikel i tidskrift (Refereegranskat)
  • 22.
    Larsson, Anne
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper.
    Ljungberg, Michael
    Jakobson Mo, Susanna
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Riklund, Katrine
    Johansson, Lennart
    Correction for scatter and septal penetration in 123I brain SPECT imaging: a Monte Carlo studyManuskript (Övrigt vetenskapligt)
  • 23.
    Larsson, Anne
    et al.
    Umeå universitet, Medicinsk fakultet, Strålningsvetenskaper, Radiofysik.
    Ljungberg, Michael
    Jakobson Mo, Susanna
    Umeå universitet, Medicinsk fakultet, Strålningsvetenskaper, Diagnostisk radiologi.
    Riklund, Katrine
    Umeå universitet, Medicinsk fakultet, Strålningsvetenskaper, Diagnostisk radiologi.
    Johansson, Lennart
    Umeå universitet, Medicinsk fakultet, Strålningsvetenskaper, Radiofysik.
    Correction for scatter and septal penetration using convolution subtraction methods and model-based compensation in I-123 brain SPECT imaging – a Monte Carlo study2006Ingår i: Physics in Medicine and Biology, Vol. 51, s. 5753-5767Artikel i tidskrift (Refereegranskat)
  • 24.
    Larsson Strömvall, Anne
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Jakobson Mo, Susanna
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Neuroimaging in nuclear medicine2022Ingår i: Handbook of nuclear medicine and molecular imaging for physicists: volume III, radiopharmaceuticals and clinical applications / [ed] Michael Ljungberg, New York: CRC Press, 2022, 1, s. 173-188Kapitel i bok, del av antologi (Övrigt vetenskapligt)
    Abstract [en]

    Nuclear medicine neuroimaging methods have evolved from mainly being used for research, to becoming established techniques in clinical neurology. In recent years, new technologies have led to increased image quality, and new radiopharmaceuticals with high clinical impact have been developed. The field is expected to become even more important in the future due to the higher prevalence of neurological disorders and the general ageing of the population. The current chapter begins with a basic medical introduction to brain anatomy and physiology. Different pathological conditions such as neurodegenerative disorders, epilepsy, and brain tumours are outlined. The chapter also includes examples of common imaging applications, such as imaging of cerebral blood flow, imaging of brain metabolism, imaging of neurotransmitter systems, and imaging of other cerebral functions such as amyloid and brain tumour imaging. A part on technology is included, discussing neuroimaging solutions for SPECT, SPECT/CT, PET, PET/CT, and PET/MR. Special considerations for optimization of SPECT and PET acquisition and reconstruction are also discussed. Important methods for evaluation, such as visual interpretation and quantitative techniques are also described, including implications for usage of reference databases.

  • 25.
    Lenfeldt, Niklas
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Åström, Björn
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Forsgren, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Jakobson Mo, Susanna
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Fractional Anisotropy and Mean Diffusion as Measures of Dopaminergic Function in Parkinson's Disease: Challenging Results2017Ingår i: Journal of Parkinson's Disease, ISSN 1877-7171, E-ISSN 1877-718X, Vol. 7, nr 1, s. 129-142Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Diffusion tensor imaging (DTI) has been purported as an imaging technique to assess dopaminergic degeneration in Parkinson’s disease.

    Objective: To test if fractional anisotropy (FA) and mean diffusion (MD) in the basal ganglia as measured by DTI correlates with dopaminergic function as measured by dopamine transporter (DAT) and dopamine D2-receptor (D2R) SPECT.

    Methods: One-hundred and eleven patients with Parkinson’s disease (71±10 years) and thirty-one controls (68±7 years) performed DTI, DAT and D2R SPECT at baseline and four follow-ups (1-year: 89 patients/zero controls; 3-year: 72/11; 5-year: 48/17; and 8-year: 13/13). Four equipment combinations of MRI scanners/SPECT gamma cameras were used during the study. Data from each combination were analyzed separately. Regions-of-interest were outlined in the substantia nigra (three subareas, DTI only) and in the striatum (putamen and caudate). Side differences and bilateral averages were correlated using linear regression. The significance threshold was set at P < 0.001 and 0.001 < P< 0.05 was defined as a trend towards significance.

    Results: For side differences, no significant correlations were observed, but in patients, there was a trend towards a negative correlation between MD in the middle nigra and putaminal DAT uptake in two combinations (P = 0.04 and P = 0.03). For averages, in patients, striatal MD correlated negatively with striatal DAT uptake in one combination (P = 0.0005) and trended towards negative correlations with striatal D2R uptake (one combination, P = 0.03) and with the sum of striatal DAT and D2R uptake (two combinations P = 0.002 and P = 0.03). FA showed no correlations in patients, and no correlations were found in controls.

    Conclusions: The poor correlations between MD and dopamine activity –and absent correlations for FA – imply that additional diffusion measures must be developed to reliably assess the dopaminergic degeneration in Parkinson’s disease.

  • 26.
    Lizana, Helena
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper.
    Johansson, L.
    Umeå universitet.
    Larsson, A.
    Umeå universitet.
    Axelsson, Jan
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper.
    Linder, J.
    Umeå universitet.
    Ögren, M.
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper.
    Varrone, A.
    Halldin, C.
    Jakobson Mo, Susanna
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper.
    Dosimetry and whole body distribution of [F-18]PE2I in healthy volunteers2016Ingår i: European Journal of Nuclear Medicine and Molecular Imaging, ISSN 1619-7070, E-ISSN 1619-7089, Vol. 43, s. S533-S533Artikel i tidskrift (Refereegranskat)
  • 27.
    Lizana, Helena
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Johansson, Lennart
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Axelsson, Jan
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Larsson, Anne
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Ögren, Mattias
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Linder, Jan
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Klinisk neurovetenskap.
    Halldin, Christer
    Varrone, Andrea
    Jakobson Mo, Susanna
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Whole-Body Biodistribution and Dosimetry of the Dopamine Transporter Radioligand 18F-FE-PE2I in Human Subjects2018Ingår i: Journal of Nuclear Medicine, ISSN 0161-5505, E-ISSN 1535-5667, Vol. 59, nr 8, s. 1275-1280Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    F-18-(E)-N-(3-iodoprop-2-enyl)-2 beta-carbofluoroethoxy-3 beta-(4'-methylphenyl) nortropane (F-18-FE-PE2I) was recently developed and has shown adequate affinity and high selectivity for the dopamine transporter (DAT). Previous studies have shown promising results for F-18-FE-PE2I as a suitable radioligand for DAT imaging. In this study, we investigated the whole-body biodistribution and dosimetry of F-18-FE-PE2I in healthy volunteers to support its utility as a suitable PET imaging agent for the DAT. Methods: Five healthy volunteers were given a mean activity of 2.5 MBq/kg, and 3 PET scans, head to thigh, were performed immediately after injection followed by 4 whole-body PET/CT scans between 0.5 and 6 h after injection. Blood samples were drawn in connection with the whole-body scans, and all urine was collected until 6 h after injection. Volumes of interest were delineated around 17 organs on all images, and the areas under the time-activity curves were calculated to obtain the total number of decays in the organs. The absorbed doses to organs and the effective dose were calculated using the software IDAC. Results: The highest activity concentration was observed in the liver (0.9%-1.2% injected activity/100 g) up to 30 min after injection. At later time points, the highest concentration was seen in the gallbladder (1.1%-0.1% injected activity/100 g). The activity excreted with urine ranged between 23% and 34%, with a mean of 28%. The urinary bladder received the highest absorbed dose (119 mu Gy/MBq), followed by the liver (46 mu Gy/MBq). The effective dose was 23 mu Sv/MBq (range, 19-28 mu Sv/MBq), resulting in an effective dose of 4.6 mSv for an administered activity of 200 MBq. Conclusion: The effective dose is within the same order of magnitude as other commonly used PET imaging agents as well as DAT agents. The reasonable effective dose, together with the previously reported favorable characteristics for DAT imaging and quantification, indicates that F-18-FE-PE2I is a suitable radioligand for DAT imaging.

  • 28.
    Nyberg, Lars
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB), Fysiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Andersson, Micael
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB), Fysiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Forsgren, Lars
    Umeå universitet, Medicinska fakulteten, Institutionen för farmakologi och klinisk neurovetenskap, Neurologi.
    Jakobson Mo, Susanna
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi.
    Larsson, Anne
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik.
    Marklund, Petter
    Nilsson, Lars-Göran
    Riklund, Katrine
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Bäckman, Lars
    Striatal dopamine D2 binding is related to frontal BOLD response during updating of long-term memory representations.2009Ingår i: NeuroImage, ISSN 1053-8119, E-ISSN 1095-9572, Vol. 46, nr 4, s. 1194-1199Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Multi-modal brain imaging was used to examine the relation between individual differences in resting-state striatal dopamine D2 binding and the magnitude of prefrontal BOLD activation during updating of long-term memory (LTM) representations. Increased activity in the left prefrontal cortex was observed when LTM updating was required, and there was a positive correlation between striatal D2 activity and the magnitude of left prefrontal activity during updating. These findings support predictions from neurocomputational models of a relation of dopaminergic neurotransmission to transient cognitive operations and related brain activity.

  • 29.
    Stegmayr, B.G.
    et al.
    Dept Internal Medicine, University Hospital, Umeå.
    Jakobson Mo, Susanna
    Dept Internal Medicine, University Hospital, Umeå.
    Rydvall, A.
    The Intensive Care Unit, University Hospital, Umeå.
    Björsell-Östling, E.
    Plasma exchange in patients with acute renal failure in the course of multiorgan failure1995Ingår i: International Journal of Artificial Organs, ISSN 0391-3988, E-ISSN 1724-6040, Vol. 18, nr 1, s. 45-52Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Multiorgan failure (MOF) due to intoxication, trauma or sepsis in the progressive late stages always include acute renal failure (ARF). The prognosis of these patients is poor despite adequate dialysis. This study included 27 consecutive patients (20 men and 7 women, age range 15-77 years) with a rapid progress of MOF including ARF, who were treated by plasma exchange as an attempt to reverse the progress of MOF. Twenty-three of the patients suffered from a septic shock. Oliguria or anuria was present in all, dialysis was performed in 16 of them, and mechanical respiratory aid in 17. Plasma exchange was performed 1-10 times and almost exclusively by centrifuge technique, using albumin and/or liquid stored plasma (in a few cases fresh frozen plasma) as colloidal replacement fluid. Twenty-two patients survived (81%) and 5 patients died. The reasons of death were cerebral haemorrhagia, brain abscess, myocardial sudden death, relapsing sepsis from multiple hepatic abscesses and a not drained psoas abscess. All survivors could leave hospital recovered from renal failure with few other sequelae. The plasma exchange technique is easy to perform despite low blood pressures by using a vein to vein access. Plasma exchange, therefore, may be tried to reverse late stages of multiorgan failure.

  • 30.
    Virel, Ana
    et al.
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB).
    Johansson, Jarkko
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Axelsson, Jan
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Radiofysik. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Ericsson, Madelene
    Umeå universitet, Medicinska fakulteten, Umeå centrum för molekylär medicin (UCMM).
    Laterveer, Rutger
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB).
    Ögren, Mattias
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Orädd, Greger
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    Jakobson Mo, Susanna
    Umeå universitet, Medicinska fakulteten, Institutionen för strålningsvetenskaper, Diagnostisk radiologi. Umeå universitet, Medicinska fakulteten, Umeå centrum för funktionell hjärnavbildning (UFBI).
    af Bjerkén, Sara
    Umeå universitet, Medicinska fakulteten, Institutionen för integrativ medicinsk biologi (IMB). Umeå universitet, Medicinska fakulteten, Institutionen för klinisk vetenskap, Neurovetenskaper.
    N-acetylcysteine decreases dopamine transporter availability in the non-lesioned striatum of the 6-OHDA hemiparkinsonian rat2022Ingår i: Neuroscience Letters, ISSN 0304-3940, E-ISSN 1872-7972, Vol. 770, artikel-id 136420Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study aimed to explore the beneficial effects of the antioxidant N-acetylcysteine (NAC) on the degenerated dopamine system. The short- and long-term regulatory mechanisms of NAC on the 6-OHDA hemiparkinsonian rat model were longitudinally investigated by performing positron emission tomography (PET) imaging using the specific dopamine transporter (DAT) radioligand [18F]FE-PE2I. The results demonstrate that after a unilateral dopamine insult NAC has a strong influence on the non-lesioned hemisphere by decreasing the levels of DAT in the striatum early after the lesion. We interpret this early and short-term decrease of DAT in the healthy striatum of NAC-treated animals as a beneficial compensatory effect induced by NAC.

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