Wani Tariq M, Dabaliz AlAwwaab, Kadah Khalid, Veneziano Giorgio, Tumin Dmitry, Tobias Joseph D
Department of Anesthesia, Sidra Medicine, Doha, Qatar.
Department of Anesthesiology and Perioperative Medicine, University Hospitals Cleveland Medical Center, Ohio, USA.
Saudi J Anaesth. 2020 Oct-Dec;14(4):493-497. doi: 10.4103/sja.SJA_292_20. Epub 2020 Sep 24.
Several studies have attempted to estimate the approximate distance from the skin-to-epidural space using different imaging modalities (computed tomography [CT], ultrasound, and magnetic resonance imaging [MRI]) and direct needle measurements. The objective of our study was to compare the distance from the skin to the epidural space (SED) at multiple levels, focusing on T, T, and L using MRI.
After institutional review board (IRB) approval, sagittal T2-weighted MRI images of the spine of 108 children in the age group ranging from 3 months to 8 years undergoing radiological evaluation in the supine position at our institution were analyzed. The SED at T and T levels (straight and inclined) and SED at L (straight) were determined and compared using repeated-measures ANOVA and paired -tests with a Bonferroni correction for 10 pairwise comparisons ( < 0.005 was considered statistically significant).
The average SED (measured straight and inclined) was 18.2 mm and 21.6 mm at T; 18.3 mm and 20.5 mm at T; and 21.8 mm (straight) at L. The repeated-measures ANOVA F-test indicated significant variability in SED ( < 0.001) among the 5 measurements obtained. At the < 0.005 significance level, corrected for multiple comparisons, the SED (straight) at T straight was shorter than the other measured distances.
The distance from the skin to the epidural space is not constant at various vertebral levels. At the levels measured, it was greatest at the lumbar level and at least at the thoracic level of T. A single predictive formula was not applicable for calculating the approximate SED at all vertebral levels.
多项研究尝试使用不同的成像方式（计算机断层扫描[CT]、超声和磁共振成像[MRI]）以及直接针测法来估计皮肤至硬膜外腔的大致距离。我们研究的目的是使用MRI比较多个节段（重点为T、T和L节段）皮肤至硬膜外腔（SED）的距离。
经机构审查委员会（IRB）批准，对我院108例年龄在3个月至8岁之间、仰卧位接受放射学评估的儿童脊柱矢状位T2加权MRI图像进行分析。确定T和T节段（直入和斜入）的SED以及L节段（直入）的SED，并使用重复测量方差分析和配对检验进行比较，采用Bonferroni校正进行10次两两比较（P<0.005被认为具有统计学意义）。
T节段直入和斜入测量的平均SED分别为18.2mm和21.6mm；T节段为18.3mm和20.5mm；L节段直入为21.8mm。重复测量方差分析F检验表明，在获得的5次测量中，SED存在显著差异（P<0.001）。在P<0.005的显著性水平下，经多重比较校正后，T节段直入的SED短于其他测量距离。
皮肤至硬膜外腔的距离在不同椎体节段并非恒定。在所测量的节段中，腰椎节段的距离最大，T节段的胸椎节段距离最小。单一预测公式不适用于计算所有椎体节段的大致SED。
