Ehlers Landon D, Opperman Patrick J, Mordeson Jack E, Thompson Jonathan R, Surdell Daniel L
Departments of1Neurosurgery and.
2Surgery, University of Nebraska, Omaha, Nebraska.
J Neurosurg Case Lessons. 2023 Aug 14;6(7). doi: 10.3171/CASE23272.
Pedicle screw impingement on vessel walls has the potential for complications due to pulsatile effects and wall erosion. Artifacts from spinal instrumentation create difficulty in accurately evaluating this interface. The authors present the first case of intravascular ultrasound (IVUS) used to characterize a pedicle screw breach into the aortic lumen.
A 21-year-old female with surgically corrected scoliosis underwent computed tomography angiography (CTA) 3 years postoperatively, which revealed a pedicle screw within the thoracic aorta lumen. Metal artifact distorted the CTA images, which prompted the decision to use intraoperative IVUS. The IVUS confirmed the noninvasive imaging findings and guided final decisions regarding aortic endograft size and location during spine hardware revision.
For asymptomatic patients presenting with pedicle screws malpositioned in or near the aorta, treatment decisions revolve around the extent of vessel wall penetration. Intraluminal depth can be obscured by artifact on computed tomography or magnetic resonance imaging or inadequately evaluated by a transesophageal echocardiogram. In our intraoperative experience, IVUS confirmed the depth of vessel lumen violation by a single pedicle screw and no wall penetration by two additional screws of concern. This was useful in deciding on thoracic endovascular aortic repair graft size and landing zone and facilitated safe spinal instrumentation removal and revision.
由于搏动效应和血管壁侵蚀，椎弓根螺钉撞击血管壁有可能引发并发症。脊柱内固定器械产生的伪影给准确评估该界面带来困难。作者报告了首例使用血管内超声（IVUS）来描述椎弓根螺钉穿破进入主动脉腔情况的病例。
一名21岁女性，脊柱侧弯手术矫正术后3年，接受计算机断层扫描血管造影（CTA）检查，结果显示一枚椎弓根螺钉位于胸主动脉腔内。金属伪影使CTA图像失真，这促使决定术中使用IVUS。IVUS证实了无创成像结果，并在脊柱内固定器械翻修期间指导了关于主动脉内支架尺寸和位置的最终决策。
对于主动脉内或主动脉附近椎弓根螺钉位置不当的无症状患者，治疗决策围绕血管壁穿透程度展开。计算机断层扫描或磁共振成像上的伪影可能会掩盖管腔内深度，经食管超声心动图也可能无法充分评估。根据我们的术中经验，IVUS证实了一枚椎弓根螺钉侵犯血管腔的深度，另外两枚相关螺钉未穿透血管壁。这有助于确定胸段血管腔内主动脉修复移植物的尺寸和着陆区，并便于安全地取出和翻修脊柱内固定器械。
