Sakamoto H, Nishikawa M, Hakuba A, Yasui T, Kitano S, Nakanishi N, Inoue Y
Department of Pediatric Neurosurgery and Neurosurgery, Osaka City General Hospital, Osaka, Japan.
Acta Neurochir (Wien). 1999;141(9):949-60; discussion 960-1. doi: 10.1007/s007010050401.
In order to treat syringomyelia associated with adult type Chiari malformation, the authors developed a method of expansive suboccipital cranioplasty (ESC) that involves enlarging the small posterior fossa to obtain a sufficient flow of cerebrospinal fluid (CSF). The relative effectiveness of ESC with the obex plugged and not plugged was also examined, as well as other factors influencing the operative results. Twenty patients without arachnoid adhesion at the major cistern underwent ESC without opening the arachnoid membrane at the major cistern. After surgery, all improved with no recurrence and CSF flow study using magnetic resonance (MR) imaging showed significant improvement of the flow at the major cistern. Another 20 patients without arachnoid adhesion also underwent ESC but with obex plugging. Sixteen improved and one displayed only temporary improvement with recurrent syringomyelia due to postoperative arachnoid adhesions. The remaining three showed no change in spite of shrinkage of the syrinx on postoperative MR imaging. These three patients had displayed pre-operative symptoms over an approximately 10-year period involving almost the entire axial plain of the spinal cord, and presented a large syrinx before surgery. In 4 patients with arachnoid adhesions, all required intra-arachnoid procedures in addition to ESC. Intra-arachnoid procedures are not necessary to facilitate restoration of CSF flow in patients without arachnoid adhesions, because ESC can release the CSF flow blockage in the major cistern even without plugging of the obex. An associated arachnoid adhesion at the major cistern or a long-standing syringomyelia with irreversible damage of the spinal cord results in a poor operative prognosis. When posterior fossa surgery fails, insufficient decompression or postoperative arachnoid adhesions at the major cistern as the cause of treatment's failure should be evaluated by CSF flow studies using phase contrast MR imaging.
为了治疗与成人型Chiari畸形相关的脊髓空洞症，作者开发了一种扩大枕下颅骨成形术（ESC），该方法包括扩大狭小的后颅窝以获得足够的脑脊液（CSF）流动。还研究了闭塞和未闭塞闩部的ESC的相对有效性，以及其他影响手术结果的因素。20例在主要脑池无蛛网膜粘连的患者接受了ESC，术中未打开主要脑池的蛛网膜。术后，所有患者均有改善且无复发，磁共振（MR）成像的脑脊液流动研究显示主要脑池的脑脊液流动有显著改善。另外20例无蛛网膜粘连的患者也接受了ESC，但进行了闩部堵塞。16例患者病情改善，1例仅出现暂时改善，术后因蛛网膜粘连导致脊髓空洞症复发。其余3例患者尽管术后MR成像显示脊髓空洞缩小，但病情无变化。这3例患者术前症状持续约10年，几乎累及脊髓整个轴位平面，并在术前出现大的脊髓空洞。4例有蛛网膜粘连的患者，除ESC外均需要进行蛛网膜下腔手术。对于无蛛网膜粘连的患者，蛛网膜下腔手术并非促进脑脊液流动恢复所必需，因为即使不堵塞闩部，ESC也可解除主要脑池的脑脊液流动阻塞。主要脑池的相关蛛网膜粘连或长期脊髓空洞症伴脊髓不可逆损伤会导致手术预后不良。当后颅窝手术失败时，应通过相位对比MR成像的脑脊液流动研究评估主要脑池减压不足或术后蛛网膜粘连是否为治疗失败的原因。
