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. 2022 Aug;41(8):1907-1914.
doi: 10.1002/jum.15867. Epub 2021 Nov 9.

What Are the Double Lines of the Fetal Cavum Septi Pellucidi on Ultrasound?

Shannon Green  1 , Dolores H Pretorius  1   2 , Amanda Crouch  2   3 , Tracy Anton  2   3 , Marni Jacobs  2 , Yoona Ho  4 , Robert Hevner  5 , Leah Lamale-Smith  2   3
Affiliations

What Are the Double Lines of the Fetal Cavum Septi Pellucidi on Ultrasound?

Shannon Green et al. J Ultrasound Med. 2022 Aug.

Abstract

Objective: To demonstrate the significance of the double line appearance of the septi pellucidi laminae (SPL) on fetal ultrasound.

Method: A total of 522 uncomplicated singleton pregnancies (15 to 39 weeks' gestational age) with fetal ultrasounds were enrolled. The presence of a single versus double line SP as well as measurement of the cavum septi pellucidi (CSP) was determined retrospectively. Ultrasound settings from the CSP images were recorded. Thickness of the SPL was measured in 20 ultrasound and 14 MRI cases; histology was reviewed from one neonate. Maternal BMI and gestational age were also recorded.

Results: The presence of double line SPL is a normal sonographic finding, seen in 47% (188/403) of normal fetuses. Thickness of the SPL in 10 cases with double line averaged 1.4 mm and in 10 cases with single line averaged 0.8 mm; MRI measurements were within 0.1 mm of the corresponding ultrasound measurements. Double line cavum was more often seen with mid-dynamic contrast range settings (5, 6) rather than high range settings (7-10) (P value <.05). The double line was only visualized on ultrasound when the angle of insonation was at or near perpendicular to the laminae; it was never visualized on coronal ultrasound imaging or MRI imaging.

Conclusion: A double line septum pellucidum lamina is a normal finding seen in almost 50% of uncomplicated singleton pregnancies. It may be attributed to borders of cell layers within each lamina that form separate specular reflections on both sides; this can be accentuated by ultrasound settings and beam angulation.

Keywords: cavum septi pellucidi; fetal cavum; fetal cavum septum pellucidum; fetal central nervous system; prenatal ultrasound; septi pellucidi laminae.

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References

    1. Winter TC, Kennedy AM, Byrne J, Woodward PJ. The cavum septi pellucidi: why is it important? J Ultrasound Med 2010; 29:427-444. https://doi.org/10.7863/jum.2010.29.3.427.
    1. Jarvis D, Griffiths PD. Normal appearances and dimensions of the foetal cavum septi pellucidi and vergae on in utero MR imaging. Neuroradiology 2020; 62:617-627. https://doi.org/10.1007/s00234-020-02364-5.
    1. Saba L, Anzidei M, Raz E, et al. MR and CT of brain's cava. J Neuroimag 2013; 23:326-335. https://doi.org/10.1111/jon.12004.
    1. Griffiths PD, Batty R, Reeves MJ, Connolly DJ. Imaging the corpus callosum, septum pellucidum and fornix in children: normal anatomy and variations of normality. Neuroradiology 2009; 51:337-345. https://doi.org/10.1007/s00234-009-0506-y.
    1. Maduram A, Farid N, Rakow-Penner R, et al. Fetal ultrasound and magnetic resonance imaging findings in suspected Septo-optic dysplasia: a diagnostic dilemma. J Ultrasound Med 2020; 39:1601-1614. https://doi.org/10.1002/jum.15252.

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