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Table 2 Contrast-to-noise ratios for all evaluated parameters

From: Optimised passive marker device visibility and automatic marker detection for 3-T MRI-guided endovascular interventions: a pulsatile flow phantom study

Evaluated parameters Median blood-artifact CNR (IQR) p-value w.r.t baseline sequence Median agar-artifact CNR (IQR) p-value w.r.t baseline sequence
GRE
Baseline sequence (a) 141.2 (129.4–150.0)   15.8 (11.2–19.9)  
Conc. 12.5 mg/mL 148.2 (133.1–155.3) < 0.001 20.7 (16.6–23.6) < 0.001
Conc. 25 mg/mL 148.5 (139.0–161.2) < 0.001 25.7 (23.4–27.4) < 0.001
Conc. 50 mg/mL 155.8 (141.3–162.1) < 0.001 28.5 (27.4–29.7) < 0.001
Sequence b 166.6 (156.8–175.3) < 0.001 14.6 (3.6–20.1) 0.276
Sequence c 240.5 (224.4–248.5) < 0.001 12.9 (7.2–25.4) 0.840
Sequence d 360.3 (349.9–366.2) < 0.001 32.7 (27.9–38.0) < 0.001
ST: 10 mm 133.8 (126.8–145.9) 0.042 10.5 (4.6–15.8) 0.014
PED: parallel 125.1 (116.9–137.6) < 0.001 10.2 (4.7–57.5) 0.026
bSSFP
Baseline sequence (e) 399.5 (389.5–406.3)   2.4 (-0.7–5.2)  
Conc. 12.5 mg/mL 387.3 (380.6–395.4) 0.003 37.6 (36.7–43.5) < 0.001
Conc. 25 mg/mL 397.1 (393.4–402.6) 0.500 57.3 (54.2–62.1) < 0.001
Conc. 50 mg/mL 478.9 (466.1–483.4) < 0.001 53.3 (51.0–59.4) < 0.001
Sequence f 572.6 (556.0–584.7) < 0.001 17.1 (14.9–23.3) < 0.001
Sequence g 766.2 (704.6–823.5) < 0.001 59.6 (55.8–65.1) < 0.001
Sequence h NA. NA NA NA
ST 10 mm 414.2 (402.5–423.6) < 0.001 1.8 (-1.5–8.5) 0.443
PED parallel 264.0 (252.9–272.2) < 0.001 2.3 (0.6–6.0) 0.800
  1. bSSFP Balanced steady-state free precession, CNR Contrast-to-noise ratio, Conc. Concentration, GRE Gradient recalled echo, NA Not available, IQR Interquartile range, PED Phase encoding direction, ST Slice thickness, TE Echo time, TR Repetition time, w.r.t. With respect to. Baseline sequences (a, e) and modified sequences (b, c, d, f, g, and h) are described in Table 1