Maija Rossi

Disease-associated inflammatory biomarker profiles in blood in different subtypes of multiple sclerosis: prospective clinical and MRI follow-up study.

To identify biomarkers of disease activity and progression in multiple sclerosis (MS), we analyzed the serum profiles of cytokines, chemokines and apoptotic molecules in different subtypes of MS including clinically isolated syndrome (CIS) and correlated their levels with clinical and volumetric MRI findings obtained over a one-year follow up. Upregulated levels of apoptotic sFas molecule were found in MS patients with a worsening EDSS score and an accumulation of hypointense lesions in MRI. In such patients, the levels of MIF appeared to be higher than in non-progressing patients. In addition, increased levels of serum TNF-α and CCL2 were found especially in primary progressive MS (PPMS). These observations suggest that serum Fas and MIF are candidate biomarkers of neurological worsening related to progressive neurodegeneration, while serum TNF-α and CCL2 reflect the presence of inflammatory responses in PPMS.

Brain Iron Deposition and Sequence Characteristics in Parkinsonism: Comparison of SWI, T2* Maps, T2-Weighted-, and FLAIR-SPACE

Objectives:To compare quantitatively T2- and T2*-based magnetic resonance imaging sequences in patients with symptoms of Parkinson disease and to evaluate the information content of those sequences regarding brain iron concentration. Materials and Methods:We imaged 51 patients with symptoms of Parkinson disease on 3-T magnetic resonance imaging with T2-weighted sampling perfection with application optimized contrasts using different flip-angle evolution (SPACE), fluid attenuation inversion recovery (FLAIR)-SPACE, susceptibility-weighted imaging (SWI), and parametric T2* sequence (MapIt). Signal analysis was performed in 22 regions of interest in the brain. Results:Correlations (r2 = 0.82…0.96) with brain iron concentration were excellent. Contrast and tissue separability ratios were best in the T2* maps and FLAIR-SPACE, respectively. Good correlations of contrast were reached between SWI and both T2-weighted SPACE and FLAIR-SPACE. Their relation to quantitative T2* values was reminiscent of a quadratic curve shape. However, separation into gray and white matter revealed a linear positive and negative correlation, respectively. Conclusions:SWI showed potential in differentiating illnesses characterized by brain iron deposition. Closely similar information was given by T2-weighted SPACE and FLAIR-SPACE, whereas other sequence comparisons revealed dispersion from intersequence agreement.

Clinical MRI for iron detection in Parkinson's disease

We studied nonheme iron in Parkinsons disease (PD) using clinically available MRI in 36 patients and 21 healthy volunteers. The subjects underwent thorough clinical investigation, including 3-T MRI. Quantitative R2* was able to reflect symptoms of PD. In addition, the clinically used susceptibility-weighted imaging differentiated between controls and patients, whereas T2-weighted imaging did not. Disease-related changes were present not only in substantia nigra but also in globus pallidus. Such changes are associated with neurodegeneration, reflecting the severity of motor impairment.

PET imaging in a longitudinal non-Hodgkin's lymphoma study: association with tumor volume

Background Computed tomography (CT) is generally used in the evaluation of the treatment response of non-Hodgkins lymphoma (NHL) patients. Instead of morphological images, positron emission tomography (PET) shows metabolic information that is connected to tumor activity, cell proliferation rate, and, thus, prognosis. Purpose To determine the prognostic value of PET for tumor volume reduction measured by CT and magnetic resonance imaging (MRI) along with clinical characteristics in NHL patients. Material and Methods We imaged 21 B-cell type NHL patients using whole-body 18F-FDG-PET at the onset and the completion of treatment and at six-month follow-up. The maximum standardized uptake value (SUVmax) was calculated. Morphological tumor volume calculations were assessed using both MRI and CT. Additionally, patients underwent thorough clinical examination including several laboratory tests. Results A high SUVmax was able to predict significant tumor volume reduction at the beginning of treatment, but the relation to pure tumor volume was poor. Conclusion The SUVmax values derived from FDG-PET seemed to correlate with volume changes but not with their absolute values or laboratory tests. Unlike MRI and CT, FDG-PET showed the disappearance of active tumors after treatment.

Parkinson's disease: interhemispheric textural differences in MR images.

RATIONALE AND OBJECTIVES Early-stage diagnosis of Parkinsons disease (PD) is essential in making decisions related to treatment and prognosis. However, there is no specific diagnostic test for the diagnosis of PD. The aim of this study was to evaluate the role of texture analysis (TA) of magnetic resonance images in detecting subtle changes between the hemispheres in various brain structures in patients with early symptoms of parkinsonism. In addition, functional TA parameters for detecting textural changes are presented. MATERIALS AND METHODS Fifty-one patients with symptoms of PD and 20 healthy controls were imaged using a 3-T magnetic resonance device. Co-occurrence matrix-based TA was applied to detect changes in textures between the hemispheres in the following clinically interesting areas: dentate nucleus, basilar pons, substantia nigra, globus pallidus, thalamus, putamen, caudate nucleus, corona radiata, and centrum semiovale. The TA results were statistically evaluated using the Mann-Whitney U test. RESULTS The results showed interhemispheric textural differences among the patients, especially in the area of basilar pons and midbrain. Concentrating on this clinically interesting area, the four most discriminant parameters were defined: co-occurrence matrix correlation, contrast, difference variance, and sum variance. With these parameters, differences were also detected in the dentate nucleus, globus pallidus, and corona radiata. CONCLUSIONS On the basis of this study, interhemispheric differences in the magnetic resonance images of patients with PD can be identified by the means of co-occurrence matrix-based TA. The detected areas correlate with the current pathophysiologic and neuroanatomic knowledge of PD.

Diffusion Tensor Imaging in NAWM and NADGM in MS and CIS: Association with Candidate Biomarkers in Sera

The aim of this study was to evaluate diffusion tensor imaging (DTI) indices in the corpus callosum and pyramidal tract in normal-appearing white matter (NAWM) and the caudate nucleus and thalamus in deep grey matter (NADGM) in all MS subtypes and clinically isolated syndrome (CIS). Furthermore, it was determined whether these metrics are associated with clinical measures and the serum levels of candidate immune biomarkers. Apparent diffusion coefficients (ADC) values were significantly higher than in controls in all six studied NAWM regions in SPMS, 4/6 regions in RRMS and PPMS and 2/6 regions in CIS. In contrast, decreased fractional anisotropy (FA) values in comparison to controls were detected in 2/6 NAWM regions in SPMS and 1/6 in RRMS and PPMS. In RRMS, the level of neurological disability correlated with thalamic FA values (r = 0.479, P = 0.004). In chronic progressive subtypes and CIS, ADC values of NAWM and NADGM were associated with the levels of MIF, sFas, and sTNF-α. Our data indicate that DTI may be useful in detecting pathological changes in NAWM and NADGM in MS patients and that these changes are related to neurological disability.

Diffusion tensor imaging correlates with lesion volume in cerebral hemisphere infarctions

BackgroundBoth a large lesion volume and abnormalities in diffusion tensor imaging are independently associated with a poor prognosis after cerebral infarctions. Therefore, we assume that they are associated. This study assessed the associations between lesion volumes and diffusion tensor imaging in patients with a right-sided cerebral infarction.MethodsThe lesion volumes of 33 patients (age 65.9 ± 8.7, 26 males and 7 females) were imaged using computed tomography (CT) in the acute phase (within 3-4 hours) and magnetic resonance imaging (MRI) in the chronic phase (follow-up at 12 months, with a range of 8-27 months). The chronic-phase fractional anisotropy (FA) and mean diffusivity (MD) values were measured at the site of the infarct and selected white matter tracts. Neurological tests in both the acute and chronic phases, and DTI lateralization were assessed with the Wilcoxon signed-rank test. The effects of thrombolytic therapy (n = 10) were assessed with the Mann-Whitney U test. The correlations between the measured parameters were analysed with Spearmans rho correlation. Bonferroni post-hoc correction was used to compensate for the familywise error rate in multiple comparisons.ResultsSeveral MD values in the right hemisphere correlated positively and FA values negatively with the lesion volumes. These correlations included both lesion area and healthy tissue. The results of the mini-mental state examination and the National Institutes of Health Stroke Scale also correlated with the lesion volume.ConclusionsA larger infarct volume is associated with more pronounced tissue modifications in the chronic stage as observed with the MD and FA alterations.

Response Analysis of Non―Hodgkin Lymphoma Using Magnetic Resonance Imaging―Based Volumes

Objective: The aim of this study was to determine the volume of non-Hodgkin lymphomas (NHLs) using semiautomatic segmentation and to correlate these results with clinical findings, treatment, and prognosis in patients with B-cell-type NHL. Methods: For this study, 29 patients with NHL underwent magnetic resonance imaging at 5 time points after onset of disease. Volumetric analysis of the tumors was accomplished with semiautomatic segmentation by the Anatomatic software. Results: The median tumor volumes from the first to the fifth examination were 468, 256, 90, 38, and 33 cm3. Good correlation with 1-dimensional and 2-dimensional measures, used as standard methods in response categorization, was found. Surprisingly, volume reductions in excess of 239 cm3 after only 1 week of chemotherapy decreased the survival probability. Conclusions: Volume measurements seem to be highly informative for prognosis in the very early stages of treatment for patients with NHL.

Computed tomography-based tumor volume in non-Hodgkin lymphoma: clinical correlation and comparison with magnetic resonance imaging.

Objectives: To evaluate the prognostic significance of tumor volume in computed tomographic (CT) images of non-Hodgkin lymphoma patients. To compare CT volumes with those measured by magnetic resonance imaging (MRI). Methods: Twenty-five patients with B cell-type non-Hodgkin lymphoma (16 men, 9 women, age range, 48-77 years) were imaged with CT at 5 time points. The volumes and volume reductions were associated with clinical characteristics and treatment outcome. The CT-derived tumor volumes were correlated with MRI volumes derived earlier for the same patients. Results: Good agreement was found between 1-dimensional (1D), 2D, and 3D analyses. The CT-derived median tumor volumes were 306 cm3, 174 cm3, 75 cm3, 28 cm3, and 15 cm3 at the 5 time points. These volumes were found to associate, for example, with mortality and tumor malignancy. The CT-based tumor volumes showed good correlation with MRI. Conclusions: Tumor volume quantification is a powerful tool that associates with clinical characteristics and treatment outcome.

Longitudinal assessment of clinically isolated syndrome with diffusion tensor imaging and volumetric MRI

The potential of diffusion tensor imaging (DTI) indices and volumes of focal lesions on conventional magnetic resonance imaging to predict conversion to multiple sclerosis (MS) was analyzed in subjects with clinically isolated syndrome (CIS) over 4 years. Twenty patients with CIS and 10 healthy controls were included in the study. The data showed an association between the volumes of T1 and fluid-attenuated inversion recovery (FLAIR) lesions and conversion to MS (T1: P=.02; FLAIR: P=.02). The worsening of DTI indices (mean diffusivity and fractional anisotropy) was primarily seen in patients progressing to MS, but clear-cut association with conversion could not be detected.