Article Figures & Data
Figures
- Fig 1.
Comparison of 1.5T and 3T axial 2D FLAIR MR images in a 50-year-old healthy woman. Images of the same regions with equivalent pulse sequences display the improved sensitivity in discrete foci−detecting capabilities (arrows) and tissue resolution (tissue-CSF distinction) of the 3T scanner. Representative images are shown. In total, FLAIR showed 11 discrete foci in the whole brain (total brain volume of discrete hyperintense foci = 310 mm3) at 1.5T and 26 discrete foci (total volume = 521 mm3) at 3T. The 1.5T FLAIR scan (A) shows less prominent number and conspicuousness of discrete foci than seen at 3T (B). The arrows show some of the differences between the images. Note that anterior capping is present on both platforms. However, a striking diffuse posterior white matter hyperintensity is present only at 3T, part of which is related to posterior capping.
- Fig 2.
A and B, Graphs show a larger hyperintense foci number (A, P = .0066) and volume (B, P = .0054) on 3T FLAIR scans than on 1.5T FLAIR scans. Histograms indicate mean; bars, standard error of the mean. Asterisks indicate a significant difference (P < .05) when comparing 1.5T with 3T in the 15 subjects scanned on both platforms. C, Distribution of total brain hyperintense foci number for each subject; squares indicate individual cases. See also Table 2.
- Fig 3.
Relationship between total brain FLAIR hyperintense foci volume/number and age at 1.5 and 3T. Scatterplots show the relationship between total FLAIR hyperintense foci volume (A and B) or number (C and D) and age on 1.5 and 3T scans in the healthy volunteers (n = 15). Each square represents a subject. Total FLAIR hyperintense foci volume (r = 0.70, P = .004) and number (r = 0.69, P = .005) at 1.5T and total FLAIR hyperintense foci volume (r = 0.74, P = .0001) and number (r = 0.72, P = .0002) at 3T show a significant correlation with age. See also Table 4.
- Fig 4.
Comparison of 1.5T and 3T FLAIR images from healthy adult subjects. A and B, Representative paired axial FLAIR images of a 47-year-old woman. Both platforms show a bright periventricular lining of the lateral ventricles (arrows) and septum pellucidum hyperintensity (arrowhead). Also note the prominent hyperintense CSF flow artifacts in the frontal horn of the left lateral ventricle (arrows). C and D, Representative paired axial FLAIR images of a 50-year-old woman. Both platforms show bilateral corticospinal tract hyperintensity (arrows). E–H, Representative paired axial FLAIR images of a 53-year-old man. Both platforms show hyperintensities (arrows) of the third ventricular lining (E and F), cerebral aqueduct lining (E and F), and within the fourth ventricle due to CSF flow (G and H). Ventricular CSF pulsation artifacts are seen to a similar degree between platforms, but only 3T FLAIR shows diffuse posterior parenchymal white matter hyperintensity (F, arrowhead).
Tables
Parameters 1.5T 3T Head coil Quadrature Receive-only phased array Number of channels 4 8 Pulse sequence 2D fast FLAIR 2D fast FLAIR FOV (cm) 24 × 24 25 × 25 Matrix size 256 × 256 256 × 256 Section thickness (mm) 2 (no gap) 2 (no gap) TR (ms) 10,000 9,000 TE (ms) 125 157 Inversion time (ms) 2700 2250 NSA 3 1 Flip angle 90° 90° Pixel size (mm) 0.938 × 0.938 × 2 0.976 × 0.976 × 2 Scanning time (min) 8.2 9.1 Note:—NSA indicates number of signal averages; FLAIR, fluid-attenuated inversion recovery.
1.5T (n = 15) 3T (n = 15) 3T vs 1.5T* (n = 15), P Value 3T (n = 22) No. discrete hyperintense foci 5.46 ± 9.15 9.4 ± 13.08 .0066 10.68 ± 14.39 Range 0–33 0–47 0–47 No. subjects with ≥1 discrete hyperintense focus 10 10 15 Total cerebral discrete hyperintense foci volume (mm3) 92.69 ± 151.62 170.33 ± 242.51 .0054 188.43 ± 257.58 Range 0–536.65 0–871.68 0–871.68 * Wilcoxon signed rank test. See also Fig 2.
1.5T (n = 15) 3T (n = 15) 3T (n = 22) Maximum length/diameter (mm)* 2.94 ± 1.14 2.75 ± 1.22 2.92 ± 1.28 Range (mm) 1.24–8.36 0.91–9.89 0.75–9.89 * No significant group differences (P = .68) when comparing 1.5T and 3T.
Correlation with Age rs P 1.5T discrete foci: total cerebral number 0.69 0.005 1.5T discrete foci: total cerebral volume 0.70 0.006 3T discrete foci: total cerebral number 0.74 0.0001 3T discrete foci: total cerebral volume 0.72 0.0002 Note:—rs = Spearman correlation coefficient. According to Choi's test for correlations, there was no difference in the correlation between age and number of hyperintense foci (p = 0.2) or age and hyperintense foci volume (p = 0.3) when comparing the 2 scanners. See also Fig 3.
In this issue
Jump to section
Related Articles
Cited By...
- Amyloid-Related Imaging Abnormalities with Emerging Alzheimer Disease Therapeutics: Detection and Reporting Recommendations for Clinical Practice
- Misdiagnosis of multiple sclerosis: Impact of the 2017 McDonald criteria on clinical practice
- Prediabetes Is Associated With Structural Brain Abnormalities: The Maastricht Study
- Current and Emerging Therapies in Multiple Sclerosis: Implications for the Radiologist, Part 1--Mechanisms, Efficacy, and Safety
- Impact of Structural Cerebral Damage in Adults With Tetralogy of Fallot
- What are White Matter Hyperintensities Made of? Relevance to Vascular Cognitive Impairment
- Evaluation of a Practical Visual MRI Rating Scale of Brain White Matter Hyperintensities for Clinicians Based on Largest Lesion Size Regardless of Location
- Comparison of 3D FLAIR, 2D FLAIR, and 2D T2-Weighted MR Imaging of Brain Stem Anatomy