Outward convexity of the basiocciput and posterior atlanto-occipital membrane are common in patients with Chiari II malformation associated with an open neural tube defect. We aimed to determine if the severity of these findings correlated with the need for future hydrocephalus treatment.

A retrospective chart and imaging review identified patients who underwent open neural tube defect repair at a quaternary care pediatric hospital from July 2014 through September 2022. Patients were classified by the need for hydrocephalus treatment and whether they received prenatal or postnatal neural tube defect repair. Measurements of imaging parameters related to posterior fossa maldevelopment and skull base remodeling were performed.

Compared with 65 patients who did not require hydrocephalus treatment, 74 patients who required treatment demonstrated statistically significantly greater mean basiocciput convexity (P < .001). While the mean basiocciput length in the hydrocephalus treatment group was smaller (P < .001), the ratio of basiocciput convexity to length was larger (P < .001). Notably, 100% of patients with a basiocciput convexity of ≥4 mm required hydrocephalus treatment. The mean posterior atlanto-occipital membrane convexity was significantly greater for patients who required hydrocephalus treatment in the postnatal group (P = .02), but not the prenatal group (P = .09).

Pediatric patients with Chiari II malformation who ultimately required surgical hydrocephalus treatment had greater outward convexity of the basiocciput but had greater posterior atlanto-occipital membrane outward convexity only if the repair was performed postnatally. Together these measurements may be useful in predicting the need for hydrocephalus treatment.

基枕骨和寰枕后膜向外凸在伴有开放性神经管缺损的 Chiari II 畸形患者中很常见。我们的目的是确定这些发现的严重程度是否与未来脑积水治疗的需要相关。

回顾性图表和影像学检查确定了 2014 年 7 月至 2022 年 9 月在四级护理儿科医院接受开放性神经管缺陷修复的患者。根据脑积水治疗的需要以及是否接受产前或产后神经管缺陷修复对患者进行分类。进行了与后颅窝发育不良和颅底重塑相关的成像参数的测量。

与 65 名不需要脑积水治疗的患者相比，74 名需要治疗的患者表现出统计学上显着更大的平均基枕凸度 ( P < .001)。虽然脑积水治疗组的平均基枕骨长度较小 ( P < .001)，但基枕骨凸度与长度的比率较大 ( P < .001)。值得注意的是，100% 基枕凸度≥4 mm 的患者需要脑积水治疗。产后组中需要脑积水治疗的患者的平均寰枕膜后凸度显着更大 ( P = .02)，但产前组则不然 ( P = .09)。

最终需要手术治疗脑积水的 Chiari II 畸形儿科患者，其基枕骨向外凸度较大，但仅在出生后进行修复时，寰枕后膜向外凸度较大。这些测量结果一起可能有助于预测脑积水治疗的需要。