目的:脑积水是软骨发育不全患者发生的神经系统风险之一。脑室-腹腔分流术(VPS)是最常见的治疗方法。然而,关于成功的第三脑室内镜造瘘术(ETV)的报告表明,ETV可能是软骨发育不全中VPS插入的良好替代方法。然而,有人说,ETV在软骨发育不全患者中在技术上要求很高。目前的研究检查了软骨发育不全患者第三脑室和脑干的解剖变异,并将发现与执行ETV的难度相关。
方法:回顾性分析了自2012年以来访问作者机构的51例软骨发育不全患者和138例无软骨发育不全的脑积水患者(48例患有肿瘤相关性脑积水,90例患有非肿瘤性脑积水)。术前T2加权矢状MR图像用于测量α(第三脑室底的陡度),β(内窥镜入射角),d1(背囊和基底分叉之间的垂直距离),和d2(鞍背与基底动脉之间的水平距离)。使用Tukey多重比较测试比较每个值。
结果:软骨发育不全患者显示出明显较小的α(p<0.001)和β(p<0.001)角,而对照组之间没有显着差异(α,p=0.947,β的p=0.836)。软骨发育不全患者的d1值显着较大(p<0.001),d2较小(p<0.001)。对照组显示相似的d1和d2值(d1的p=0.415,d2的p=0.154)。较小的α和β值意味着软骨发育不全患者的第三脑室底板比其他脑积水患者更垂直。内窥镜的接触角很小,增加心室造瘘术装置滑入漏斗状隐窝的风险。此外,大的d1表示基底动脉向上移动,小的d2表示基底动脉更靠近背囊,潜在增加基底动脉损伤的风险。
结论:软骨发育不全患者的颅骨和脑部解剖与其他脑积水患者有显著差异,第三脑室地板更陡,基底动脉更靠近背宫。因为这些解剖学差异导致软骨发育不全患者难以进行ETV,当计划为患者提供ETV时,应考虑这些差异。
OBJECTIVE: Hydrocephalus is one of the neurological risks occurring in patients with
achondroplasia. Ventriculoperitoneal shunt (VPS) insertion is the most common treatment. However, reports of successful endoscopic third ventriculostomy (ETV) suggest that ETV may be a good alternative to VPS insertion in achondroplasia. However, it has been stated that ETV in
achondroplasia patients is technically demanding to perform. The current study examined the anatomical variations of the third ventricle and the brainstem in achondroplasia patients and correlated the findings with the difficulty of performing ETV.
METHODS: A retrospective analysis of 51 patients with
achondroplasia and 138 hydrocephalus patients without achondroplasia (48 patients had tumor-related hydrocephalus and 90 patients had hydrocephalus of nontumorous origin) who have visited the authors\' institution since 2012 was performed. Preoperative T2-weighted sagittal MR images were used to measure α (steepness of the third ventricle floor), β (endoscopic angle of incidence), d1 (vertical distance between the dorsum sellae and basilar bifurcation), and d2 (horizontal distance between the dorsum sellae and basilar artery). Each value was compared using the Tukey multicomparison test.
RESULTS: Achondroplasia patients showed significantly smaller α (p < 0.001) and β (p < 0.001) angles, while there were no significant differences between the control groups (p = 0.947 for α, p = 0.836 for β). The d1 value was significantly larger in
achondroplasia patients (p < 0.001), and d2 was smaller (p < 0.001). The control groups showed similar d1 and d2 values (p = 0.415 for d1, p = 0.154 for d2). Smaller α and β values meant that in achondroplasia patients the third ventricle floor stood more vertically than in other patients with hydrocephalus, and the endoscopic contact angles were small, increasing the risk of ventriculostomy devices slipping down into the infundibular recess. Additionally, a large d1 meant that the basilar artery was shifted upward and a small d2 indicated that the basilar artery was located closer to the dorsum sellae, potentially increasing the risk of basilar artery damage.
CONCLUSIONS: Achondroplasia patients\' skull and brain anatomies were significantly different from those of other hydrocephalus patients, with steeper third ventricle floors and basilar arteries closer to the dorsum sellae. Because these anatomical differences lead to difficulties in performing ETVs in achondroplasia patients, such differences should be considered when ETV is planned for the patients.