Milbrandt Todd A, Sucato Daniel J
Shriners Hospital for Children and University of Kentucky, Lexington, KY 40502, USA.
Spine (Phila Pa 1976). 2007 May 20;32(12):E348-53. doi: 10.1097/BRS.0b013e318059aeda.
Analysis axial magnetic resonance images (MRIs) identifying the position of the aorta in left thoracic scoliosis and normal patients.
To determine the position of the aorta in patients with left thoracic scoliosis and to compare these findings with those seen in normal patients.
Screws placed during an anterior spinal fusion and instrumentation for right thoracic scoliosis are in proximity to the aorta, which is primarily due to the position of the aorta on the posterolateral left aspect of the vertebra. There are no studies that have evaluated the aorta in left thoracic scoliosis.
A retrospective review of all patients with an MRI with left thoracic scoliosis (Group LTS) was performed and compared with patients with a normal straight spine (Group N). Axial MRI images from T4 to L3 in both groups were analyzed to include the aorta-vertebral angle (AVA), where 0 degrees = aorta directly lateral to the left and 180 degrees = directly lateral to the right.
There were 20 patients in Group LTS and 43 patients in Group N. There were no differences in age (13.1 vs. 14.0 years) or gender (52% vs. 62% females) between the LTS and N groups. The aorta was positioned more anterior (larger AVA) to the vertebral body at levels T4 thru T11 (average, 70.1 degrees vs. 40.6 degrees) and L3 (77.1 degrees vs. 70.9 degrees) in Group LTS compared with group N (P < 0.05). With increasing thoracic coronal Cobb angle, the aorta was positioned more laterally to the right (larger AVA) at T8 and T10 (P < 0.05). In the LTS group, curves greater than 40 degrees had a larger AVA (91.4 degrees vs. 57.7 degrees) at apical levels (T7-T10) than for curves < or =40 degrees (P < 0.05).
In left thoracic LTS, the aorta is positioned more anteriorly and to the right (toward the concavity) compared with patients with a straight spine. This position will allow full access to the convexity of the left curve to perform an anterior fusion/release as well as instrumentation and is not in the trajectory of a well-placed anterior screw. This relative safety was not seen at the apex of larger curves (>40 degrees).
分析轴向磁共振成像（MRI）以确定左胸段脊柱侧弯患者和正常患者中主动脉的位置。
确定左胸段脊柱侧弯患者中主动脉的位置，并将这些结果与正常患者的结果进行比较。
在右胸段脊柱侧弯的前路脊柱融合和器械置入过程中所置入的螺钉靠近主动脉，这主要是由于主动脉位于椎体左后外侧的位置。尚无研究评估左胸段脊柱侧弯中的主动脉情况。
对所有有左胸段脊柱侧弯MRI的患者（LTS组）进行回顾性研究，并与脊柱正常笔直的患者（N组）进行比较。分析两组从T4至L3的轴向MRI图像，以纳入主动脉-椎体角（AVA），其中0度 = 主动脉直接位于左侧，180度 = 直接位于右侧。
LTS组有20例患者，N组有43例患者。LTS组和N组在年龄（13.1岁对14.0岁）或性别（女性分别为52%对62%）方面无差异。与N组相比，LTS组中在T4至T11水平（平均，70.1度对40.6度）和L3水平（77.1度对70.9度）主动脉位于椎体更前方（AVA更大）（P < 0.05）。随着胸段冠状面Cobb角增加，在T8和T10水平主动脉位于更右侧（AVA更大）（P < 0.05）。在LTS组中，大于40度的曲线在顶椎水平（T7 - T10）的AVA（91.4度对57.7度）大于小于或等于40度的曲线（P < 0.05）。
与脊柱正常笔直的患者相比，在左胸段LTS中，主动脉位于更前方且更偏向右侧（朝向凹侧）。该位置将允许充分显露左弯的凸侧以进行前路融合/松解以及器械置入，并且不在位置良好的前路螺钉的轨迹上。在较大曲线（>40度）的顶点未观察到这种相对安全性。
