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- Jakobson Mo, Susanna, 1968-, et al.
(author)
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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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In: Nuclear Medicine Communications. - : Lippincott Williams & Wilkins. - 0143-3636 .- 1473-5628. ; 34:10, s. 978-989
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Journal article (peer-reviewed)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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| 2. |
- Jakobson Mo, Susanna, et al.
(author)
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Cross-camera comparison of ROI-based semi-quantitative 123I-IBZM SPECT data in healthy volunteers using an anthropomorphic phantom for calibration
- 2013
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In: Acta Radiologica. - : SAGE Publications. - 0284-1851 .- 1600-0455. ; 54:5, s. 549-556
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Journal article (peer-reviewed)abstract
- 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.
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| 3. |
- Linder, Jan, 1957-, et al.
(author)
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Degenerative changes were common in brain magnetic resonance imaging in patients with newly diagnosed Parkinson's disease in a population-based cohort
- 2009
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In: Journal of Neurology. - Berlin : Springer. - 0340-5354 .- 1432-1459. ; 256:10, s. 1671-1680
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Journal article (peer-reviewed)abstract
- The aim of this study was to investigate newly diagnosed patients with Parkinson's disease (PD) with structural magnetic resonance imaging (MRI), to compare them with healthy controls, to relate the findings to clinical subtypes - tremor dominant (TD) or postural instability and gait difficulty (PIGD) - and to investigate the relationship between both the duration from onset of symptoms to diagnosis and the severity of symptoms and the MRI findings. Patients with a definite PD diagnosis were compared to patients with a probable PD diagnosis. We hypothesized that the PIGD subtype, the probable PD group, a greater symptom severity and a longer symptom duration would all be associated with more frequent pathological findings. Sixty-six PD patients were included and examined with MRI, 35 with the PIGD subtype and 23 with the TD subtype. Fifty-three had definite PD and 13 probable PD. Thirty healthy individuals, matched for age and sex, served as controls. Degenerative changes in the cerebellar cortex and the superior cerebellar peduncle were significantly more common in the probable PD group than in the controls, suggesting the possibility of an emerging atypical parkinsonian disorder. No significant MRI differences were found between definite PD and controls, between definite PD and probable PD, nor between PIGD and TD. No significant associations were found between duration to diagnosis and MRI results, nor between severity of symptoms and MRI results. Thus, although pathological MRI findings were common they can not be used to separate subgroups of PD in newly diagnosed patients.
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| 4. |
- Stenman, Katarina, et al.
(author)
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1H HRMAS NMR Derived Bio-markers Related to Tumor Grade, Tumor Cell Fraction, and Cell Proliferation in Prostate Tissue Samples
- 2011
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In: Biomarker Insights. - : Libertas Academica Ltd. - 1177-2719. ; 6, s. 39-47
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Journal article (peer-reviewed)abstract
- A high-resolution magic angle spinning NMR spectroscopic approach is presented for evaluating the occurrence, amount and aggressiveness of cancer in human prostate tissue samples. Using this technique, key metabolites in malignant and non-malignant samples (n = 149) were identified, and patterns of their relative abundance were analyzed by multivariate statistical methods. Ratios of various metabolites – including (glycerophophorylcholine + phosphorylcholine)/creatine, myo-inositol/scyllo-inositol, scyllo-inositol/creatine, choline/creatine, and citrate/creatine – correlated with: i) for non-malignant tissue samples, the distance to the nearest tumor and its Gleason score and; ii) the fraction of tumor cells present in the sample; and iii) tumor cell proliferation (Ki67 labelling index). This NMR-based approach allows the extraction of information that could be useful for developing novel diagnostic methods for prostate cancer.
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