闭锁型脑膜脑膨出的顶盖板形态异常：常被低估的影像征象
该回顾性研究分析了13例顶枕部闭锁型脑膜脑膨出患儿的MRI，在矢状3D T1WI上评估顶盖板形态。顶盖板形态异常见于8例（61.5%），其中6例（75%）呈鸟嘴样，常伴大脑大静脉池扩大、幕上提等后颅窝中线结构异常。顶盖板形态异常与静脉异常及背侧中线结构异常并存时，可为闭锁型脑膜脑膨出提供辅助诊断价值。
要点
- 闭锁型脑膜脑膨出伴顶盖板鸟嘴样或下丘板选择性受累时，应按3D T1矢状位评价。
- 大脑大静脉池扩大见于全部病例，无法作为排除征象。
- 顶枕部闭锁型脑膜脑膨出需注意融合窦等颅内静脉异常。
核心结论
- 顶盖板形态异常是闭锁型脑膜脑膨出较为常见且常被低估的影像征象。
- 顶盖板形态异常与颅内静脉异常及背侧中线结构异常共同出现，提示存在共同发育背景，可为闭锁型脑膜脑膨出提供额外诊断价值。
研究设计与样本
- 回顾性研究，纳入13例顶叶和/或枕叶闭锁型脑膜脑膨出患儿，均为MRI检查。
- 在矢状3D T1加权图像上评价顶盖板轮廓、厚度、是否呈鸟嘴样，并记录形态异常范围，即整个顶盖板受累还是仅下丘板受累。
- 同时记录局灶性纤维蒂、脑脊液裂、小脑幕异常、静脉异常以及后颅窝中线结构异常等伴随影像表现。
- 数据分析采用描述性统计。
关键影像表现/征象
- 13例中8例（61.5%）出现顶盖板形态异常，其中6例（75%）表现为鸟嘴样顶盖板。
- 顶盖板形态异常范围包括整个顶盖板受累和仅下丘板选择性受累两种模式。
- 全部患者（100%）均出现小脑幕上抬，12例（92.3%）表现为大脑大静脉池扩大。
- 8例（61.5%）观察到融合窦，顶叶病变中全部出现该静脉异常，而单纯枕叶病变中仅1例出现。
- 病例同时存在其他多种后中线及后颅窝发育异常。
诊断标准与关键数值
- 矢状3D T1WI上出现鸟嘴样顶盖板轮廓、顶盖板增厚，或顶盖板部分区域，尤其是下丘板选择性形态异常，可判为顶盖板形态异常。
- 同时满足顶盖板形态异常、大脑大静脉池扩大、小脑幕上抬以及融合窦等静脉异常时，应提示闭锁型脑膜脑膨出的诊断。
临床应用与阅片要点
- 对疑诊闭锁型脑膜脑膨出的儿童MRI，应专门行正中矢状位3D T1WI观察顶盖板，避免遗漏鸟嘴样改变。
- 顶盖板鸟嘴样改变不应仅指向典型的中脑导水管狭窄相关诊断，闭锁型脑膜脑膨出也需纳入鉴别。
- 发现顶盖板形态异常时，应进一步观察大脑大静脉池、小脑幕、中线静脉与后颅窝伴发畸形，以提高诊断把握度。
局限性
- 本研究为回顾性设计。
- 样本量小，仅有13例患者。
以上解读依据论文摘要（全文未开放获取或许可不允许翻译转载）。
英文原文（摘要）· 点击展开
OBJECTIVE: To systematically evaluate tectal plate morphology in patients with atretic cephaloceles and to determine whether tectal dysmorphism represents an underrecognized imaging feature.
METHODS: In this retrospective study, MRI examinations of 13 pediatric patients with parietal and/or occipital atretic cephaloceles were reviewed. Tectal morphology was assessed on sagittal 3D T1-weighted images for contour, thickness, and the presence of tectal beaking, and the extent of dysmorphic involvement, either the entire tectal plate or selective involvement of the inferior colliculus, was recorded. Associated imaging findings, including venous anomalies, fibrous stalk, CSF cleft, tentorial abnormalities, and additional midline and posterior fossa anomalies, were also evaluated. Descriptive statistics were used for data analysis.
RESULTS: Tectal plate dysmorphism was identified in 8 of 13 patients (61.5%), and 6 of these (75%) demonstrated a tectal beaking configuration. The pattern of involvement included both the entire tectal plate and selective involvement of the inferior colliculus. Persistent falcine sinus was observed in 8 patients (61.5%), occurring in all parietal lesions but in only one isolated occipital lesion. Additional imaging findings included tentorial peaking, observed in all patients (100%), and enlargement of the superior cerebellar cistern in 12 patients (92.3%), along with various midline and posterior fossa anomalies.
CONCLUSION: Tectal dysmorphism is a relatively frequent and underrecognized imaging feature of atretic cephalocele. Its association with venous anomalies and dorsal midline abnormalities suggests a shared developmental background and may provide additional diagnostic value.
引用
- Sahap, Atalan, Fitoz, et al. Tectal plate dysmorphism in atretic cephaloceles: an underrecognized but frequent imaging feature. Eur J Radiol. 2026. PMID: 42225045. doi:10.1016/j.ejrad.2026.112974
供执业医师工作参考，不替代临床判断；数值与分级以指南原文为准。