Skip to main content

Table 1 Distribution of two measurements of the flow volume for 2D flow and two 4D flow phase-contrast sequences (GRAPPA2 and k-t-GRAPPA5) with different rotational frequencies of the blood pump

From: Validation of two accelerated 4D flow MRI sequences at 3 T: a phantom study

Rotational pump output, rpm

Venc, cm/s

Pump reference flow volume

2D flow PC flow volume

4D flow PC GRAPPA2 flow volume

4D flow PC k-t-GRAPPA5 flow volume

L/min

L/min, mean ± SD

L/min (difference from the pump reference)

L/min, mean ± SD

L/min (difference from the pump reference)

L/min, mean ± SD

L/min (difference from the pump reference)

L/min, mean ± SD

Exam 1

Exam 2

Exam 1

Exam 2

Exam 1

Exam 2

Exam 1

Exam 2

1,500

40

1.7

1.7

1.70 ± 0.0

1.7 (+ 0.0)

1.7 (+ 0.0)

1.70 ± 0.0

1.7 (+ 0.0)

1.8 (+ 0.1)

1.75 ± 0.1

1.8 (+ 0.1)

1.7 (+ 0.0)

1.75 ± 0.1

2,000

50

2.4

2.3

2.35 ± 0.1

2.4 (+ 0.0)

2.4 (+ 0.1)

2.40 ± 0.0

2.4 (+ 0.0)

2.4 (+ 0.1)

2.40 ± 0.0

2.3 (-0.1)

2.4 (+ 0.1)

2.35 ± 0.0

2,500

60

3.0

3.0

3.00 ± 0.0

3.1 (+ 0.1)

3.1 (+ 0.1)

3.10 ± 0.0

3.1 (+ 0.1)

3.1 (+ 0.1)

3.10 ± 0.0

3.1 (+ 0.1)

3.2 (+ 0.2)

3.15 ± 0.1

3,000

70

3.8

3.8

3.80 ± 0.0

3.8 (+ 0.0)

3.8 (+ 0.0)

3.80 ± 0.0

3.7 (-0.1)

3.8 (+ 0.0)

3.75 ± 0.1

3.8 (+ 0.0)

3.9 (+ 0.1)

3.85 ± 0.1

3,500

85

4.5

4.5

4.50 ± 0.0

4.6 (+ 0.1)

4.6 (+ 0.1)

4.60 ± 0.0

4.4 (-0.1)

4.5 (+ 0.0)

4.45 ± 0.1

4.6 (+ 0.1)

4.7 (+ 0.2)

4.65 ± 0.1

4,000

100

5.3

5.3

5.30 ± 0.0

5.4 (+ 0.1)

5.4 (+ 0.1)

5.40 ± 0.0

5.2 (-0.1)

5.3 (+ 0.0)

5.25 ± 0.1

5.4 (+ 0.1)

5.5 (+ 0.2)

5.45 ± 0.1

4,500

110

6.1

6.1

6.10 ± 0.0

6.2 (+ 0.1)

6.2 (+ 0.1)

6.20 ± 0.0

6.0 (-0.1)

6.2 (+ 0.1)

6.10 ± 0.1

6.2 (+ 0.1)

6.3 (+ 0.2)

6.25 ± 0.1

5,000

125

6.9

6.9

6.90 ± 0.0

7.0 (+ 0.1)

7.1 (+ 0.2)

7.05 ± 0.1

6.9 (+ 0.0)

6.9 (+ 0.0)

6.90 ± 0.1

7.0 (+ 0.1)

7.1 (+ 0.2)

7.05 ± 0.1

5,500

140

7.7

7.7

7.70 ± 0.0

7.8 (+ 0.1)

7.9 (+ 0.2)

7.85 ± 0.1

7.6 (-0.1)

7.7 (+ 0.0)

7.65 ± 0.1

7.8 (+ 0.1)

7.9 (+ 0.2)

7.85 ± 0.1

  1. No significant differences between measurements and pump reference were observed (p = 0.994)
  2. 2D two-dimensional, 4D four-dimensional, cm/s centimetres per second, GRAPPA generalised autocalibrating partially parallel acquisition, L/min litres per minute, PC phase-contrast, SD standard deviation of the mean, Venc velocity encoding