Labandeyra Hipólito, Sala-Blanch Xavier, Prats-Galino Alberto, Puigdellívol-Sánchez Anna
Laboratory of Surgical Neuroanatomy (LSNA), Human Anatomy and Embryology Unit, Faculty of Medicine and Health Sciences, Universitat de Barcelona, 08036 Barcelona, Spain.
Division of Regional Anesthesia, Anesthesiology Service, HM Delfos Hospital, 08023 Barcelona, Spain.
NeuroSci. 2024 Dec 3;5(4):623-634. doi: 10.3390/neurosci5040044.
Cauda equina nerve roots may become damaged during neuraxial anesthesia, and post-puncture headache may appear in the case of cerebrospinal fluid leakage if needle tips are deformed due to bone contact when several attempts are needed. Our aim was to verify the correlation between skin-transverse process distance (st) and skin-dural sac distance (d) for calculation of optimal angles in a free visual guide and as a reference for the maximal depth to be traversed by the needle. Randomly selected ex vivo samples ( = 10) were flexed to reproduce the position of the lumbosacral spine during spinal anesthesia. Spinal needles were inserted perpendicular to the skin either blindly or following the inferred paramedian angle corresponding to ultrasound-measured (d). After computed tomography and three-dimensional reconstruction, both (st) and (d) were measured, and the Pearson correlation index was calculated. A free 3D-PDF tool was used to illustrate the potential affectation of nerve cuffs by needles located lateral to the dural sac. Correlation between (d) and (st) was 0.84-0.93 at L4L5-L3L4 intervertebral levels, and most needle tips were located within the spinal canal, but some traversed the zone where nerve cuffs emerge. In conclusion, ultrasound may determine if a perpendicular needle insertion is viable at midline. If not, the optimal paramedian angle and maximal depth may be determined by measuring (st).
马尾神经根在椎管内麻醉期间可能会受损，若多次穿刺时因针尖端与骨质接触而变形导致脑脊液漏，则可能出现穿刺后头痛。我们的目的是验证皮肤至横突距离（st）与皮肤至硬脊膜囊距离（d）之间的相关性，以便在无视觉辅助引导下计算最佳进针角度，并作为针穿刺最大深度的参考。随机选取10个离体样本进行弯曲，以重现腰段脊柱在脊髓麻醉时的位置。将脊髓穿刺针垂直于皮肤盲目插入，或按照与超声测量的（d）相对应的旁正中进针角度插入。在计算机断层扫描和三维重建后，测量（st）和（d），并计算皮尔逊相关指数。使用一个免费的3D-PDF工具来说明位于硬脊膜囊外侧的针可能对神经袖套造成的影响。在L4L5 - L3L4椎间水平，（d）与（st）的相关性为0.84 - 0.93，大多数针尖位于椎管内，但有些则穿过了神经袖套发出的区域。总之，超声可确定在中线垂直进针是否可行。若不可行，则可通过测量（st）来确定最佳旁正中进针角度和最大深度。
