Department of Biomedical Imaging and Image-Guided Therapy, Medical University of Vienna, Vienna, Austria.
Department of Anatomy and Biomechanics, Karl Landsteiner University of Health Sciences, Krems, Austria.
Ultrasound Obstet Gynecol. 2020 Jul;56(1):78-85. doi: 10.1002/uog.21890.
Normal cognitive development usually requires a structurally intact and complete cerebellar vermis. The aim of this study was to evaluate whether quantification by fetal magnetic resonance imaging (MRI) of vermis- and brainstem-specific imaging markers improves the definition of cystic posterior fossa malformations (cPFM).
Fetuses diagnosed with cPFM that had an available midsagittal plane on T2-weighted MRI were identified retrospectively and compared with gestational-age (GA) matched brain-normal controls. Fetuses with cPFM were assigned to three groups, according to standard criteria (vermian size and brainstem-vermis (BV) angle): normal vermian area and BV angle < 25° (Group 1); reduced vermian area and/or BV angle of 25-45° (Group 2); and reduced vermian area and BV angle > 45° (Group 3; Dandy-Walker malformation (DWM) group). The number of differentiable vermian lobules and the areas of the vermis, mesencephalon, pons and medulla oblongata were quantified, correlated with and controlled for GA, and compared between the study groups.
In total, 142 cases of cPFM were included, with a mean GA of 25.20 ± 5.11 weeks. Cases comprised Blake's pouch cyst (n = 46), arachnoid cyst (n = 12), inferior vermian hypoplasia (n = 5), megacisterna magna (n = 35) and classic DWM (n = 44). In the control group, 148 fetuses were included, with a mean GA of 25.26 ± 4.12 weeks. All quantified areas and the number of differentiable vermian lobules had a significant positive correlation with GA. The number of vermian lobules and the areas of all quantified regions, except for that of the medulla oblongata, differed significantly between the study groups (P ≤ 0.015 for all). The control group had the highest number of differentiable vermian lobules and the DWM group had the lowest (P < 0.01).
Prenatal MRI assessment of vermian lobules is a useful addition to standard neuroradiological and neurosonographic techniques. The quantification of vermian lobules using fetal MRI allows further differentiation of cPFM into subgroups and thereby improves the classification of hindbrain malformations. © 2019 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.
正常的认知发育通常需要结构完整和完整的小脑蚓部。本研究的目的是评估通过胎儿磁共振成像（MRI）对蚓部和脑干特异性成像标志物的定量分析是否能提高对囊性后颅窝畸形（cPFM）的定义。
回顾性地确定了在 T2 加权 MRI 上有中矢状面的诊断为 cPFM 的胎儿，并与胎龄（GA）匹配的脑正常对照组进行比较。根据标准标准（蚓部大小和脑干-蚓部（BV）角）将 cPFM 胎儿分为三组：正常蚓部面积和 BV 角<25°（组 1）；减小的蚓部面积和/或 BV 角为 25-45°（组 2）；和减小的蚓部面积和 BV 角>45°（组 3；Dandy-Walker 畸形（DWM）组）。定量分析可区分的蚓部小叶数量和蚓部、中脑、脑桥和延髓的面积，与 GA 相关并进行 GA 控制，并在研究组之间进行比较。
总共纳入了 142 例 cPFM 病例，平均 GA 为 25.20±5.11 周。病例包括 Blake 袋囊肿（n=46）、蛛网膜囊肿（n=12）、下蚓部发育不良（n=5）、巨脑桥池（n=35）和经典 DWM（n=44）。在对照组中，纳入了 148 名胎儿，平均 GA 为 25.26±4.12 周。所有定量区域和可区分的蚓部小叶数量均与 GA 呈显著正相关。研究组之间的可区分的蚓部小叶数量和所有定量区域的面积均有显著差异（所有 P 值均≤0.015）。对照组具有最高数量的可区分的蚓部小叶，而 DWM 组具有最低的（P<0.01）。
产前 MRI 评估蚓部小叶是对标准神经影像学和神经超声技术的有益补充。使用胎儿 MRI 对蚓部小叶进行定量分析可进一步将 cPFM 分为亚组，从而改善后脑畸形的分类。©2019 作者。约翰威立父子公司出版由国际超声协会代表在妇产科超声。
