Size of the intracranial optic nerve and optic tract in neonates at term-equivalent age at magnetic resonance imaging

作者：Oyama Jun^*; Mori Kouichi; Imamura Masatoshi; Mizushima Yukiko; Tateishi Ukihide

来源：Pediatric Radiology, 2016, 46(4): 527-533.

DOI：10.1007/s00247-015-3495-5

• Magnetic resonance imaging
• Neonate
• Optic nerve
• Optic tract
• Size

The expected MRI-based dimensions of the intracranial optic nerve and optic tract in neonates are unknown.
To evaluate the sizes of the intracranial optic nerve and optic tract in neonates at term-equivalent age using MRI.
We retrospectively analyzed brain MRI examinations in 62 infants (28 boys) without intracranial abnormalities. The images were obtained in infants at term-equivalent age with a 1.5-tesla MRI scanner. We measured the widths and heights of the intracranial optic nerve and optic tract and calculated the cross-sectional areas using the formula for an ellipse.
The means +/- standard deviation of the width, height and cross-sectional area of the intracranial optic nerve were 2.7 +/- 0.2 mm, 1.7 +/- 0.2 mm and 3.5 +/- 0.5 mm(2), respectively. The width, height and cross-sectional area of the optic tract were 1.5 +/- 0.1 mm, 1.6 +/- 0.1 mm and 2.0 +/- 0.2 mm(2), respectively. Using univariate and multivariate analyses, we found that postmenstrual age showed independent intermediate positive correlations with the width (r = 0.48, P < 0.01) and cross-sectional area (r = 0.40, P < 0.01) of the intracranial optic nerve. The lower bounds of the 95% prediction intervals for the width and cross-sectional area of the intracranial optic nerve were 0.07 x (postmenstrual age in weeks) - 0.46 mm, and 0.17 x (postmenstrual age in weeks) - 4.0 mm(2), respectively.
We identified the sizes of the intracranial optic nerve and optic tract in neonates at term-equivalent age. The postmenstrual age at MRI independently positively correlated with the sizes.

• 出版日期2016-4