Article Figures & Data
Figures
- Fig 1.
Magnification of the fetal posterior fossa and vermis and demonstration of biometric parameters. 1) Maximum superoinferior diameter. 2) Anteroposterior diameter. 3) Perimeter and surface area.
- Fig 2.
Midsagittal view of the fetal brain demonstrating the vermis. A, 2D US. B, 3D US. C, MR imaging.
- Fig 3.
Comparison of measurements (mean ± SD, 95% CI) obtained by 2D US, 3D US, and MR imaging. A, SI. B, AP. C, Perimeter. D, SA.
Tables
Gestational Age (wk) Imaging Modality US 2D US 3D MRI %5 Median %95 %5 Median %95 %5 Median %95 21 10.69 11.95 12.57 11.10 12.30 14.60 22 10.42 12.72 14.40 11.50 13.60 14.90 23 11.71 12.79 13.84 13.00 14.40 16.50 24 13.33 13.79 14.82 13.40 15.35 17.50 25 13.85 15.17 16.66 14.50 16.00 17.80 26 13.75 16.09 18.45 15.60 16.80 19.50 27 14.05 17.07 18.78 16.70 18.70 20.20 13.30 14.13 15.05 28 16.08 17.09 19.72 16.30 18.80 23.80 13.66 14.58 15.73 29 17.29 18.72 20.33 18.10 20.00 22.20 13.25 16.02 17.54 30 17.83 18.56 19.62 18.40 20.50 23.60 15.77 17.38 20.76 31 18.03 19.34 20.75 18.10 21.30 23.80 16.16 18.02 19.34 32 17.68 19.33 20.59 19.00 21.40 26.60 16.75 18.67 20.12 33 16.78 20.93 22.94 20.70 22.70 24.50 18.37 19.48 21.21 34 19.11 20.38 23.34 20.40 22.30 28.50 17.90 19.56 21.30 35 19.62 21.75 24.29 20.90 22.00 27.00 18.27 19.83 23.29 Note:—%5 indicates 5th percentile; %95, 95th percentile.
Gestational Age (wk) Imaging Modality US 2D US 3D MRI %5 Median %95 %5 Median %95 %5 Median %95 21 7.08 7.79 8.71 5.70 8.10 10.30 22 7.51 9.51 10.62 7.40 9.15 12.40 23 7.27 8.72 10.25 6.30 8.80 11.00 24 8.96 9.49 10.64 8.60 9.85 11.00 25 9.58 10.73 13.17 9.90 10.50 14.60 26 8.76 11.28 14.17 8.10 11.30 12.80 27 10.06 11.44 12.69 9.30 12.50 14.80 9.11 9.33 11.10 28 10.75 12.32 14.94 9.20 12.30 15.90 8.90 9.97 12.04 29 10.09 12.61 15.01 11.20 12.80 14.40 8.93 11.05 13.28 30 11.06 13.36 14.94 10.70 13.70 16.80 10.39 11.92 15.01 31 12.69 14.01 15.81 11.80 14.60 18.00 11.07 12.30 13.96 32 11.93 13.87 17.38 10.70 15.20 18.40 11.40 13.04 13.90 33 12.63 15.11 17.83 11.80 13.05 19.70 11.91 13.26 15.22 34 12.36 15.94 17.82 12.00 15.60 21.40 11.18 13.77 15.10 35 13.84 16.40 17.40 12.60 15.75 18.90 12.70 14.83 17.17 Note:—%5 indicates 5th percentile; %95, 95th percentile.
Gestational Age (wk) Imaging Modality US 2D US 3D MRI %5 Median %95 %5 Median %95 %5 Median %95 21 36.20 40.94 44.80 37.20 41.70 54.60 22 37.04 46.80 48.64 40.60 47.30 49.40 23 41.20 45.07 49.39 41.50 46.90 55.20 24 48.10 49.89 51.80 45.00 49.20 56.70 25 46.74 52.41 62.86 48.80 53.30 63.30 26 50.00 57.87 65.98 50.80 58.30 68.60 27 48.97 59.08 67.10 51.40 64.00 69.30 50.05 50.67 57.75 28 53.26 60.42 69.40 57.60 66.20 82.60 48.22 53.30 58.16 29 58.58 65.42 69.37 58.80 66.40 77.20 50.58 56.85 61.09 30 60.08 64.98 70.36 57.80 70.20 82.80 55.07 61.10 72.13 31 61.18 65.67 71.97 64.10 71.10 82.40 59.38 66.21 71.93 32 62.13 67.31 77.88 65.30 74.60 96.10 61.20 68.11 73.79 33 68.13 71.38 76.83 73.70 77.95 82.50 64.98 70.90 78.33 34 67.05 73.97 80.43 66.50 80.10 92.80 67.21 71.06 83.00 35 70.20 75.19 79.16 68.50 79.70 100.20 69.44 75.93 86.11 Note:—%5 indicates 5th percentile; %95, 95th percentile.
Gestational Age (wk) Imaging Modality US 2D US 3D MRI %5 Median %95 %5 Median %95 %5 Median %95 21 82.41 99.27 112.76 70.00 98.00 126.00 22 92.43 114.88 131.10 95.00 125.00 141.00 23 100.38 125.18 146.12 92.00 119.00 164.00 24 130.89 138.14 154.26 118.00 140.50 175.00 25 135.91 170.76 198.12 127.00 155.00 233.00 26 139.84 189.49 234.09 150.00 193.00 215.00 27 158.35 198.22 234.51 176.00 223.00 255.00 127.08 143.50 152.34 28 182.56 222.26 293.91 177.00 218.00 376.00 132.66 157.32 176.64 29 215.82 246.64 293.68 199.00 235.00 319.00 140.89 175.90 204.92 30 228.12 255.40 282.77 223.00 286.00 330.00 170.35 196.48 251.86 31 240.25 268.21 299.06 219.00 298.00 355.00 181.44 214.24 239.03 32 241.17 282.90 330.94 263.00 297.00 412.00 202.60 229.60 272.65 33 274.90 325.12 370.45 295.00 308.00 383.00 207.49 246.18 266.11 34 283.93 340.38 405.17 256.00 327.00 540.00 224.95 246.21 322.73 35 302.87 350.00 392.47 280.00 323.00 478.00 242.75 279.97 363.32 Note:—%5 indicates 5th percentile; %95, 95th percentile.
Linear Regression Coefficient Model Summary Unstandardized βa Standardized β Adjusted R2 SI US 2D 0.693 0.916 0.839 US 3D 0.833 0.899 0.806 MRI 0.742 0.811 0.656 AP US 2D 0.559 0.871 0.757 US 3D 0.574 0.800 0.637 MRI 0.606 0.791 0.624 Perimeter US 2D 2.340 0.912 0.831 US 3D 2.989 0.889 0.790 MRI 3.243 0.843 0.708 SA US 2D 18.487 0.948 0.897 US 3D 19.670 0.897 0.804 MRI 17.587 0.844 0.711 ↵a P < .001 for all coefficients.
- Table 6:
Comparison of imaging modalities for each biometric measurement: estimated marginal means 95% CI
SI AP Perimeter SA Mean 95% CI Mean 95% CI Mean 95% CI Mean 95% CI At gestational age 29.6 wka US 2D 18.10 17.91–18.30 12.99 12.80–13.19 63.34 62.60–64.08 247.45 243.13–251.77 US 3D 19.80 19.58–20.01 13.18 12.97–13.39 67.77 66.97–68.5 258.43 253.77–263.10 MRI 16.47 16.23–16.70 11.40 11.17–11.64 60.68 59.80–61.55 181.04 175.90–186.1 For examinations preformed at ≥27 wk of gestation: mean gestational age, 31.3 wk US 2D 19.28 19.05–19.51 13.88 13.64–14.11 67.20 66.31–68.10 276.99 271.53–282.45 US 3D 17.80 17.57–18.03 12.36 12.13–12.59 65.34 64.48–66.20 212.94 207.68–218.20 MRI 21.34 21.08–21.61 14.20 13.93–14.46 73.28 72.28–74.29 294.12 288.00–300.23 ↵a Mean gestational age for all populations (516 fetuses).
Vermian Measurement Differences in Measurements of Vermian Biometry Mean (95% CI of the Difference) ICC (95% CI) US 2D, intraobserver variability SI −0.34 ± 0.73 (−0.54 to −0.13) 0.94 (0.91 to 0.97) AP 0.71 ± 1.02 (0.42 to 1.00) 0.85 (0.75 to 0.91) Perimeter 0.93 ± 2.7 (0.16 to 1.7) 0.93 (0.88 to 0.96) SA 2.2 ± 14.4 (2.04 to −1.81) 0.97 (0.95 to 0.98) US 3D, interobserver variability SI −0.47 ± 1.5 (−0.89 to −0.43) 0.95 (0.92 to 0.97) AP −0.26 ± 0.55 (−0.41 to −0.10) 0.98 (0.98 to 0.99) Perimeter 1.05 ± 10.66 (−1.97 to 4.08) 0.81 (0.7 to 0.89) SA −1.2 ± 2.6 (−1.95 to −0.44) 0.999 (0.99 to 1.0) MRI, intraobserver variability SI 0.60 ± 0.66 (0.42 to 0.79) 0.94 (0.91 to 0.97) AP 0.55 ± 1.05 (0.25 to 0.85) 0.79 (0.66 to 0.88) Perimeter 1.2 ± 4.05 (0.05 to 2.3) 0.88 (0.81 to 0.93) SA −0.36 ± 10.1 (−3.2 to 2.5) 0.97 (0.96 to 0.98) Vermian Measurement Differences in Measurements of Vermian Biometry Mean (95% CI of the Difference) ICC (95% CI) US 2D, interobserver variability SI −0.07 ± 1.15 (−0.40 to 0.25) 0.86 (0.77 to 0.92) AP 0.92 ± 1.32 (0.54 to 1.2) 0.71 (0.54 to 0.82) Perimeter 2.4 ± 4.6 (1.15 to 3.81) 0.81 (0.69 to 0.88) SA 8.3 ± 31.18 (−0.47 to 17.25) 0.86 (0.76 to 0.91) US 3D, interobserver variability SI −0.07 ± 1.15 (−0.40 to 0.25) 0.86 (0.77 to 0.92) AP 0.92 ± 1.32 (0.54 to 1.2) 0.71 (0.54 to 0.82) Perimeter 2.4 ± 4.6 (1.15 to 3.81) 0.81 (0.69 to 0.88) SA 8.3 ± 31.18 (−0.47 to 17.25) 0.86 (0.76 to 0.91) MRI, interobserver variability SI −0.47 ± 1.5 (−0.89 to −0.43) 0.95 (0.92 to 0.97) AP −0.26 ± 0.55 (−0.41 to −0.10) 0.98 (0.98 to 0.99) Perimeter 1.05 ± 10.66 (−1.97 to 4.08) 0.81 (0.7 to 0.89) SA −1.2 ± 2.6 (−1.95 to −0.44) 0.99 (0.99 to 1.0)
