青少年Chiari畸形伴脊髓空洞患儿后颅窝减压术术中分流与术后转归的相关性研究

Syrinx resolution after posterior fossa decompression in adolescents with Chiari malformation： necessity of syringomyelia shunting

目的探讨青少年Chiari畸形伴脊髓空洞患儿后颅窝减压术（posterior fossa decompression，PFD）中施行空洞分流的必要性。方法回顾性分析2005年6月至2009年12月间我院后颅窝减压术治疗的40例青少年Chiari畸形伴脊髓空洞症患儿，根据术中是否施行脊髓空洞-蛛网膜下腔分流分为PFD＋空洞分流组（A组）与单纯PFD组（B组）。其中，A组患儿18例，男6例，女12例，平均年龄13．5岁；B组患儿22例，男14例，女8例，平均年龄13．1岁。于T1加权MRI上测量术前及末次随访时空洞长度、最大脊髓空洞直径／脊髓直径值（S／C值），统计分析两组患儿的脊髓空洞改善程度是否存在差异。结果术前两组患儿性别、年龄、空洞大小均无显著差异。A组随访时间12-33个月，平均（16．8±6．1）个月；B组随访时间12-25个月，平均（16．4±3．3）个月。末次随访时，两组患儿空洞长度（9．0±6．5）个椎体、S／C值0．56±0．28均较其术前（13．1±4．5）个椎体和0．78±0.07显著减小，差异有统计学意义（P〈0．05）。A组平均空洞长度改善率、S／C值改善率分别为（34．4±37．5）％和（30．3±33．3）％；B组平均空洞长度改善率、S／C值改善率分别为（52．1±29．3）％和（41．2±31．2）％；组间比较差异没有统计学意义（P〉0．05）。A组空洞长度改善值为（4．1±5．1）节段，B组为（5．9±4．4）节段；A组S／C改善值为0．22土0．23，B组为0．32±0．26，组间差异均无统计学意义（P〉0．05）。结论空洞分流术对行后颅窝减压术的青少年Chiari畸形患儿的空洞转归无明显影响，然而其远期疗效有待更大样本、更长随访时间的研究行进一步证实。

Objective To evaluate the necessity of syrinx shunting in adolescents undergoing posterior fossa decompression （PFD） for Chiari malformation and syringomyelia. Methods A total of 40 patients, aged 10 to 18 years, undergoing PFD for Chiari malformation between June 2005 and December 2009 were identified and retrospectively reviewed. They were classified into 2 groups based on whether or not shunting was performed., group A with PFD plus syrinx shunting （M： F = 6： 12; mean age, 13. 5 years） and group B with PFD alone （M：F= 14：8; mean age, 13. 1 years）. On T1- weighted magnetic resonance imaging, syrinx length as well as maximal syrinx/cord （S/C） ratio was evaluated pre- and postoperatively. The extent of syrinx resolution was compared between two groups with Student＇s t test. Results During PFD, age, gender, syrinx length and S/C ratio did not differ significantly between two groups （P〉0. 05）. The average follow-up periods of groups A and B were 16. 8 ± 6. 1（12-33）and 16. 4 ± 3. 3（12-25）months respectively. At the last follow-up, syrinx length and maximal S/C ratio decreased significantly in both groups （P〈0.05）. The improvement rate of syrinx length and S/C ratio averaged 0. 34 ± 0. 37 and 0. 30 ± 0. 33 for Group A versus 0. 52 ± 0. 29 and 0.41 ± 0.31 for Group B respectively. No significant inter-group differences existed in the extent of improvement in syrinx length or S/C ratio （P〉0. 05）. Conclusions In neurosurgical treatment of syringomyelia associated with Chiari malformation, syrinx shunting plus PFD shows no advantage over PFD alone in terms of decreasing syrinx length or S/C ratio.