Department of Neurosurgery, Graduate School of Medicine, Osaka University, 2-2 Yamadaoka, Suita, Osaka, Japan.
Department of Neurosurgery, Osaka Gyoumeikan Hospital, Osaka, Japan.
Sci Rep. 2021 Sep 27;11(1):19152. doi: 10.1038/s41598-021-98546-z.
Syrinx resolution has been associated with an increase in the size of the posterior subarachnoid space (pSAS) after foramen magnum decompression (FMD) for type I Chiari malformation (CM1). The present study investigated the influence of pSAS increase on syrinx resolution and symptom improvement after FMD. 32 patients with CM1 with syrinx were analyzed retrospectively. FMD was performed for the 24 patients with CM1 with syrinx. pSAS areas were measured on sagittal magnetic resonance images. Neurological symptoms were grouped into three clinical categories and scored. The rates of symptom improvement in the CM1 patients with syrinx after FMD was 19.7% ± 12.9%. The mean times to the improvement of neurological symptoms in CM1 patients with syrinx after FMD was 23.4 ± 50.2 months. There were no significant differences between the patients with and without improvement of syrinx after FMD with regard to the age, length of tonsillar herniation, BMI, and preoperative pSAS areas. The rate of increase in the pSAS areas was significantly higher in the group with syrinx improvement within 1 year (p < 0.0001). All patients with a > 50% rate of increase in the pSAS area showed syrinx improvement. Our results suggested that the increasing postoperative pSAS area accelerated the timing of syrinx resolution.
小脑扁桃体下疝畸形 1 型（CM1）患者行后颅窝减压术（FMD）后，后蛛网膜下腔空间（pSAS）增大与脊髓空洞症（Syrinx）缓解相关。本研究旨在探讨 pSAS 增大对 FMD 后 Syrinx 缓解和症状改善的影响。回顾性分析了 32 例合并 Syrinx 的 CM1 患者，其中 24 例行 FMD。在矢状面磁共振图像上测量 pSAS 面积。将神经症状分为三组进行评分。FMD 后，CM1 伴 Syrinx 患者的症状改善率为 19.7%±12.9%。FMD 后 CM1 伴 Syrinx 患者神经症状改善的平均时间为 23.4±50.2 个月。FMD 后 Syrinx 改善与未改善的患者在年龄、小脑扁桃体下疝长度、BMI 和术前 pSAS 面积方面无显著差异。在 1 年内 Syrinx 改善的患者中，pSAS 面积增加率显著更高（p<0.0001）。所有 pSAS 面积增加率>50%的患者均出现 Syrinx 改善。我们的结果表明，术后 pSAS 面积的增加加速了 Syrinx 的缓解。
