| 1. |
- af Bjerkén, Sara, et al.
(författare)
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Reliability and validity of visual analysis of [18F]FE-PE2I PET/CT in early Parkinsonian disease
- 2023
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Ingår i: Nuclear medicine communications. - : Wolters Kluwer. - 0143-3636 .- 1473-5628. ; 44:5, s. 397-406
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Tidskriftsartikel (refereegranskat)abstract
- 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.
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| 2. |
- Gref, Margareta, 1950-, et al.
(författare)
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99mTc-diethylenetriamine penta-acetate plasma clearance in advanced renal failure by the mean sojourn time approach
- 2009
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Ingår i: Nuclear medicine communications. - 0143-3636 .- 1473-5628. ; 30:3, s. 202-205
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: The single-sample 99mTc-diethylenetriamine penta-acetate (DTPA) clearance method by Christensen and Groth is recommended by the Radionuclides in Nephrourology Committee on Renal Clearance for use in adults with an estimated glomerular filtration rate (GFR) ≥30 ml/min. The purpose of this study was to test a new 99mTc-DTPA single-sample low clearance formula for GFR lesser than 30 ml/min. Methods: Twenty-one adult patients (29 investigations) were included. Reference clearance was calculated with both 51Cr-EDTA and 99mTc-DTPA according to Brøchner-Mortensen with samples drawn between 3 and 24 h. Single-sample clearance was calculated from a 24 h sample using the low clearance formula Equation (Uncited)Image Tools C(t) is the activity of the tracer in the plasma sample t minutes after the injection and Q0 is the injected amount. ECV is the extracellular volume in ml defined as the distribution volume of the tracer. ECV is estimated from the body surface area as ECV=8116.6×body surface area-28.2. Results: The mean difference between reference and 99mTc-DTPA single-sample clearance was -0.5 ml/min (SD 1.0 ml/min) for 99mTc-DTPA and -0.8 ml/min (SD 1.2 ml/min) for 51Cr-EDTA as reference clearance. Conclusion: In adult patients it is possible, even with GFR lesser than 30 ml/min, to get an accurate determination of 99mTc-DTPA plasma clearance from a single sample using the mean sojourn time approach. The blood sample should be obtained about 24 h after injection of the GFR tracer.
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| 3. |
- Jakobson Mo, Susanna, 1968-, et al.
(författare)
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I-123-FP-Cit and I-123-IBZM SPECT uptake in a prospective normal material analysed with two different semiquantitative image evaluation tools
- 2013
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Ingår i: Nuclear Medicine Communications. - : Lippincott Williams & Wilkins. - 0143-3636 .- 1473-5628. ; 34:10, s. 978-989
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Tidskriftsartikel (refereegranskat)abstract
- 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.
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| 4. |
- Jakobson Mo, Susanna, et al.
(författare)
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Long-term dopamine transporter imaging in Parkinson's disease treated with zona incerta stimulation
- 2016
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Ingår i: Nuclear medicine communications. - 0143-3636 .- 1473-5628. ; 37:5, s. 499-508
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Tidskriftsartikel (refereegranskat)abstract
- 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.
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| 5. |
- Jakobson Mo, Susanna, et al.
(författare)
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VNTR polymorphism in the SLC6A3 gene does not influence dopamine transporter availability measured by [18F]FE-PE2I PET or [123I]FP-Cit SPECT
- 2022
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Ingår i: Nuclear medicine communications. - : Wolters Kluwer. - 0143-3636 .- 1473-5628. ; 43:3, s. 247-255
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Tidskriftsartikel (refereegranskat)abstract
- 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.
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| 6. |
- Larsson, Anne, et al.
(författare)
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A method for attenuation and scatter correction of brain SPECT based on computed tomography images
- 2003
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Ingår i: Nuclear medicine communications. - 0143-3636 .- 1473-5628. ; 24:4, s. 411-420
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Tidskriftsartikel (refereegranskat)abstract
- A method for attenuation and scatter correction of brain single photon emission computed tomography (SPECT) is described where computed tomography (CT) images of the brain are used for the calculation of attenuation maps. The method is evaluated for the substance 99mTc hexamethylpropylene amine oxime. A transmission dependent scatter correction is utilized and is based on ray sums calculated through the attenuation map. A method based on external markers is used to align the SPECT and CT image volumes. The markers need only to be present during the SPECT acquisition since the corresponding landmarks can be found without markers on the CT images. The mismatching has been investigated for five patients who have undergone both a CT examination and a SPECT examination with markers. Twelve individuals from the staff have pointed out the landmarks on the CT images, with an average standard deviation of 3.4 mm. Reconstructions with an attenuation map shifted the corresponding 95% confidence interval have been performed to obtain an estimation of the quantitative uncertainty caused by the mismatching, and quantitative errors of up to 6.3% have been measured. At present the method is probably most useful when groups of patients are studied.
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| 7. |
- Sandgren, Kristina, et al.
(författare)
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Histopathology-validated lesion detection rates of clinically significant prostate cancer with mpMRI, [68Ga]PSMA-11-PET and [11C]Acetate-PET
- 2023
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Ingår i: Nuclear medicine communications. - : Lippincott Williams & Wilkins. - 0143-3636 .- 1473-5628. ; 44:11, s. 997-1004
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Tidskriftsartikel (refereegranskat)abstract
- Objective: PET/CT and multiparametric MRI (mpMRI) are important diagnostic tools in clinically significant prostate cancer (csPC). The aim of this study was to compare csPC detection rates with [68Ga]PSMA-11-PET (PSMA)-PET, [11C] Acetate (ACE)-PET, and mpMRI with histopathology as reference, to identify the most suitable imaging modalities for subsequent hybrid imaging. An additional aim was to compare inter-reader variability to assess reproducibility.Methods: During 2016–2019, all study participants were examined with PSMA-PET/mpMRI and ACE-PET/CT prior to radical prostatectomy. PSMA-PET, ACE-PET and mpMRI were evaluated separately by two observers, and were compared with histopathology-defined csPC. Statistical analyses included two-sided McNemar test and index of specific agreement.Results: Fifty-five study participants were included, with 130 histopathological intraprostatic lesions >0.05 cc. Of these, 32% (42/130) were classified as csPC with ISUP grade ≥2 and volume >0.5 cc. PSMA-PET and mpMRI showed no difference in performance (P = 0.48), with mean csPC detection rate of 70% (29.5/42) and 74% (31/42), respectively, while with ACE-PET the mean csPC detection rate was 37% (15.5/42). Interobserver agreement was higher with PSMA-PET compared to mpMRI [79% (26/33) vs 67% (24/38)]. Including all detected lesions from each pair of observers, the detection rate increased to 90% (38/42) with mpMRI, and 79% (33/42) with PSMA-PET.Conclusion: PSMA-PET and mpMRI showed high csPC detection rates and superior performance compared to ACE-PET. The interobserver agreement indicates higher reproducibility with PSMA-PET. The combined result of all observers in both PSMA-PET and mpMRI showed the highest detection rate, suggesting an added value of a hybrid imaging approach.
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