MRI is becoming increasingly available and more common. However, it is a long examination, within a limited space, and making strong demands on the patient for proper co-operation. Using survey data collected by prospective questionnaire, this work examines the influence of patient preparation and type of MRI device on patients' subjective perception of the examination. The work analysed 800 patient questionnaires from 7 radiology centres, 12 MRI machines from 3 manufacturers. It was shown that 20% of patients were not informed at all or only insufficiently about the MRI examination by the referring physician, and this had a statistically significant effect on subjective perception as to the length of the examination. In claustrophobic patients, there was no significant difference in the perception of MRI examination between machine types (open vs. closed) or between bore size. This work demonstrated the influence of technical parameters of MRI devices on some other evaluated aspects in terms of patients' perception of MRI examinations (such as noise perception or peripheral nerves irritation) and that the preparation prior to the examination itself plays also an important role. Sufficient explanation from the referring physician, good workplace time management, and sufficient communication with the patient influence the subjective perception of the examination and thus indirectly its diagnostic benefit.
- MeSH
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- magnetická rezonanční tomografie * metody MeSH
- mladiství MeSH
- mladý dospělý MeSH
- percepce MeSH
- prospektivní studie MeSH
- průzkumy a dotazníky MeSH
- senioři MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- senioři MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND AND PURPOSE: This study's aim was to investigate diffusion properties of the cervical spinal cord in patients with clinically isolated syndrome (CIS) through analysis of diffusion tensor imaging (DTI) data and thereby to assess the capacity of this technique for predicting the progression of CIS to clinically definite multiple sclerosis (CDMS). METHODS: The study groups were comprised of 47 patients with CIS (15 of them with progression to CDMS within 2 years of follow-up) and 57 asymptomatic controls. All patients and controls had undergone magnetic resonance imaging (MRI) of the cervical spine including DTI and brain MRI. Methodological approaches included histogram analysis of the cervical cord's diffusion parameters and evaluation of T2 hyperintense lesions of the spinal cord and brain. All parameters were compared between the study groups. Sensitivity and specificity calculations were then performed with a view to predicting conversion to CDMS. RESULTS: The patient subgroups defined by progression to CDMS differed significantly in values of fractional anisotropy (FA) kurtosis measured within white matter (WM) and normal-appearing WM (NAWM). The same parameters also differed significantly when patients with progression to CDMS were compared to healthy controls. Receiver operating characteristic (ROC) analysis revealed sensitivity and specificity of FA kurtosis of WM and NAWM of 93% and 72%, respectively, in terms of predicting CIS to CDMS progression. CONCLUSION: This study presents evidence that histogram analysis of diffusion parameters of the cervical spinal cord in patients with CIS may be helpful in predicting conversion to CDMS.
- MeSH
- anizotropie MeSH
- dospělí MeSH
- krční mícha diagnostické zobrazování patologie MeSH
- lidé středního věku MeSH
- lidé MeSH
- mozek diagnostické zobrazování patologie MeSH
- prognóza MeSH
- progrese nemoci * MeSH
- roztroušená skleróza diagnostické zobrazování patologie MeSH
- senzitivita a specificita MeSH
- zobrazování difuzních tenzorů * MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Robust voxelwise analysis using tract-based spatial statistics (TBSS) together with permutation statistical method is standardly used in analyzing diffusion tensor imaging (DTI) of brain. A similar analytical method could be useful when studying DTI of cervical spinal cord. Based on anatomical data of sixty-four healthy volunteers, white (WM) and gray matter (GM) masks were created and subsequently registered into DTI space. Using TBSS, two skeleton types were created (single line and dilated for WM as well as GM). From anatomical data, percentage rates of overlap were calculated for all skeletons in relation to WM and GM masks. Voxelwise analysis of fractional anisotropy values depending on age and sex was conducted. Correlation of fraction anisotropy values with age of subjects was also evaluated. The two WM skeleton types showed a high overlap rate with WM masks (~94%); GM skeletons showed lower rates (56% and 42%, respectively, for single line and dilated). WM and GM areas where fraction anisotropy values differ between sexes were identified (p < .05). Furthermore, using voxelwise analysis such WM voxels were identified where fraction anisotropy values differ depending on age (p < .05) and in these voxels linear dependence of fraction anisotropy and age (r = -0.57, p < .001) was confirmed by regression analysis. This dependence was not proven when using WM anatomical masks (r = -0.21, p = .10). The analytical approach presented shown to be useful for group analysis of DTI data for cervical spinal cord.
- MeSH
- algoritmy * MeSH
- anizotropie MeSH
- bílá hmota diagnostické zobrazování MeSH
- difuzní magnetická rezonance * MeSH
- dospělí MeSH
- krční mícha diagnostické zobrazování MeSH
- lidé středního věku MeSH
- lidé MeSH
- počítačové zpracování obrazu metody MeSH
- zdraví dobrovolníci pro lékařské studie MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
BACKGROUND: Segmentation of the gray and white matter (GM, WM) of the human spinal cord in MRI images as well as the analysis of spinal cord diffusivity are challenging. When appropriately segmented, diffusion tensor imaging (DTI) of the spinal cord might be beneficial in the diagnosis and prognosis of several diseases. PURPOSE: To evaluate the applicability of a semiautomatic algorithm provided by ITK-SNAP in classification mode (CLASS) for segmenting cervical spinal cord GM, WM in MRI images and analyzing DTI parameters. STUDY TYPE: Prospective. SUBJECTS: Twenty healthy volunteers. SEQUENCES: 1.5T, turbo spin echo, fast field echo, single-shot echo planar imaging. ASSESSMENT: Three raters segmented the tissues by manual, CLASS, and atlas-based methods (Spinal Cord Toolbox, SCT) on T2 -weighted and DTI images. Masks were quantified by similarity and distance metrics, then analyzed for repeatability and mutual comparability. Masks created over T2 images were registered into diffusion space and fractional anisotropy (FA) values were statistically evaluated for dependency on method, rater, or tissue. STATISTICAL TESTS: t-test, analysis of variance (ANOVA), coefficient of variation, Dice coefficient, Hausdorff distance. RESULTS: CLASS segmentation reached better agreement with manual segmentation than did SCT (P < 0.001). Intra- and interobserver repeatability of SCT was better for GM and WM (both P < 0.001) but comparable with CLASS in entire spinal cord segmentation (P = 0.17 and P = 0.07, respectively). While FA values of whole spinal cord were not influenced by choice of segmentation method, both semiautomatic methods yielded lower FA values (P < 0.005) for GM than did the manual technique (mean differences 0.02 and 0.04 for SCT and CLASS, respectively). Repeatability of FA values for all methods was sufficient, with mostly less than 2% variance. DATA CONCLUSION: The presented semiautomatic method in combination with the proposed approach to data registration and analyses of spinal cord diffusivity can potentially be used as an alternative to atlas-based segmentation. LEVEL OF EVIDENCE: 1 Technical Efficacy: Stage 2 J. Magn. Reson. Imaging 2018;47:1217-1227.
- MeSH
- algoritmy MeSH
- anizotropie MeSH
- bílá hmota diagnostické zobrazování MeSH
- difuzní magnetická rezonance * MeSH
- dospělí MeSH
- echoplanární zobrazování * MeSH
- krční mícha diagnostické zobrazování MeSH
- lidé MeSH
- mladý dospělý MeSH
- odchylka pozorovatele MeSH
- počítačové zpracování obrazu metody MeSH
- poranění míchy diagnostické zobrazování MeSH
- prospektivní studie MeSH
- šedá hmota diagnostické zobrazování MeSH
- strojové učení MeSH
- zobrazování difuzních tenzorů * MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH