1 Duke University School of Medicine, Durham, NC.
2 Department of Radiology, Duke University Medical Center, Box 3808, Durham, NC 27710.
AJR Am J Roentgenol. 2018 Aug;211(2):426-431. doi: 10.2214/AJR.18.19606. Epub 2018 May 29.
The purpose of this study was to assess the rate of inadvertent injection into the retrodural space of Okada during CT fluoroscopy-guided interlaminar epidural steroid injection in the cervical spine.
Images from cases of cervical interlaminar epidural steroid injection under CT fluoroscopic guidance performed at a single institution between November 2009 and November 2015 were obtained and reviewed. For all cases, the following information was recorded: presence or absence of contrast material within the Okada space, cervical anatomic level at which the procedure was performed, laterality of approach, trainee presence, and years of proceduralist experience. Two-tailed chi-square tests were used to assess categoric variables, and t tests were performed to assess for continuous variables predictive of nontarget injection.
A total of 974 CT fluoroscopy-guided cervical interlaminar epidural steroid injections were identified in 728 patients. The presence of contrast material in the retrodural space of Okada was identified in 2.9% of cases (28/974). All cases of inadvertent injection were identified and corrected intraprocedurally. The greatest rate of inadvertent injection (4.6% [18/389]) occurred at C5-6. No variables predictive of inadvertent injection into the Okada space were identified. There was a 0.4% (4/974) complication rate, and all complications were minor.
We identified a 2.9% rate of unintended injection into the retrodural space of Okada during cervical interlaminar epidural steroid injection. If unrecognized, these nontarget injections can result in treatment failure in a subset of patients who undergo cervical interlaminar epidural steroid injection. Future study is warranted to assess the rate of inadvertent Okada injection under conventional fluoroscopy and to compare the rates of detection between the two imaging-guided modalities.
本研究旨在评估在 CT 透视引导下颈椎间层硬膜外类固醇注射过程中奥卡达（Okada）误入硬膜后间隙的发生率。
获取并回顾了 2009 年 11 月至 2015 年 11 月期间在一家机构进行的 CT 透视引导下颈椎间层硬膜外类固醇注射病例的图像。所有病例均记录奥卡达间隙内有无对比剂、手术颈椎解剖水平、入路侧别、受训者存在情况和术者经验年限等信息。采用双侧卡方检验评估分类变量，采用 t 检验评估对非目标注射有预测意义的连续变量。
共确定了 728 例患者的 974 例 CT 透视引导下颈椎间层硬膜外类固醇注射。2.9%（28/974）的病例发现奥卡达硬膜后间隙有对比剂。所有误入注射均被发现并在术中纠正。奥卡达误入注射发生率最高（4.6%[18/389]）的节段为 C5-6。未发现奥卡达空间注射的预测变量。并发症发生率为 0.4%（4/974），所有并发症均为轻微。
我们发现颈椎间层硬膜外类固醇注射时奥卡达硬膜后间隙的非预期注射率为 2.9%。如果未被识别，这些非目标注射可能导致接受颈椎间层硬膜外类固醇注射的一部分患者治疗失败。需要进一步研究评估在常规透视下奥卡达意外注射的发生率，并比较两种影像学引导方式的检测率。
