Magnetic resonance imaging
-
To evaluate the diagnostic potential based on histogram analysis of IVIM parameters between uterine cervical cancers (CC) - normal myometrium (Myo) versus CC - gluteus maximus muscle (GM) and to study the feasibility of histogram analysis of IVIM parameters to differentiate the early from locally advanced stage CCs. ⋯ The histogram analysis of IVIM parameters depicted that gluteus maximus served better reference tissue in comparison to myometrium. The histogram index 75th percentile of ADC, D, D*, and f may serve a diagnostic biomarker to differentiate the early from locally advanced stage CCs.
-
7.0 Tesla (T) high-resolution diffusion tensor imaging (DTI) can supply information on changing microstructures in cranial nerves. We investigated DTI parameters and the feasibility of DTI criteria for diagnosing trigeminal neuralgia (TN). In this study, 14 patients (28 hemispheres) of mean age 49.0 years (range, 31-64) with TN underwent DTI using 7.0 TMRI. ⋯ Nuclei were not significantly different among patients with TN. Barrow Neurological Institute (BNI) pain scores did not correlate with affected sides. 7.0 T DTI was useful for detecting neurovascular compression in patients with TN. The increased signal-to-noise ratio provided by 7 T MRI should be advantageous for increasing spatial resolution to detect microstructure changes to trigeminal nerves in patients with TN.
-
Quantitative MRI (qMRI) provides surrogate brain maps of myelin and iron content. After spatial normalization to a common standard brain space, these may be used to detect altered myelination and iron accumulation in clinical populations. Here, volumetric and combined volumetric and surface-based (CVS) normalization were compared to identify which procedure would afford the greatest sensitivity to inter-regional differences (contrast), and the lowest inter-subject variability (under normal conditions), of myelin- and iron-related qMRI parameters, in whole-brain group-level studies. ⋯ Across cortical voxels, the inter-individual variability of myelin and iron qMRI maps were comparable between CVS (with no smoothing) and DARTEL-VBQ (with smoothing). CVS normalization of qMRI maps preserves higher myelin and iron contrast than DARTEL-VBQ over the entire brain, while exhibiting comparable variability in the cerebral cortex without extra smoothing. Thus, CVS may prove useful for detecting small microstructural differences in whole-brain group-level qMRI studies.
-
Multicenter Study
Scan-rescan repeatability and cross-scanner comparability of DTI metrics in healthy subjects in the SPRINT-MS multicenter trial.
To assess intrascanner repeatability and cross-scanner comparability for diffusion tensor imaging (DTI) metrics in a multicenter clinical trial. ⋯ The good repeatability of the DTI metrics among the 27 scanners used in this study confirms the feasibility of combining DTI data from multiple centers using high angular resolution sequences. Our observations support the feasibility of longitudinal multicenter clinical trials using DTI outcome measures. The noise floor level and SNFR are important parameters that must be assessed when comparing studies that used different scanner models.
-
This study sought to investigate the feasibility of three-dimensional MPRAGE in identifying the lipid-rich necrotic core (LRNC) and calcification (CA) of carotid atherosclerotic plaques. ⋯ MPRAGE sequence might be a potential non-contrast enhanced imaging tool for identification of carotid LRNC and CA.