Wade Ryckie G, Tanner Steven F, Teh Irvin, Ridgway John P, Shelley David, Chaka Brian, Rankine James J, Andersson Gustav, Wiberg Mikael, Bourke Grainne
Department of Plastic and Reconstructive Surgery, Leeds Teaching Hospitals Trust, Leeds, United Kingdom.
Faculty of Medicine and Health Sciences, University of Leeds, Leeds, United Kingdom.
Front Surg. 2020 Apr 16;7:19. doi: 10.3389/fsurg.2020.00019. eCollection 2020.
Cross-sectional MRI has modest diagnostic accuracy for diagnosing traumatic brachial plexus root avulsions. Consequently, patients either undergo major exploratory surgery or months of surveillance to determine if and what nerve reconstruction is needed. This study aimed to develop a diffusion tensor imaging (DTI) protocol at 3 Tesla to visualize normal roots and identify traumatic root avulsions of the brachial plexus. Seven healthy adults and 12 adults with known (operatively explored) unilateral traumatic brachial plexus root avulsions were scanned. DTI was acquired using a single-shot echo-planar imaging sequence at 3 Tesla. The brachial plexus was visualized by deterministic tractography. Fractional anisotropy (FA) and mean diffusivity (MD) were calculated for injured and avulsed roots in the lateral recesses of the vertebral foramen. Compared to healthy nerves roots, the FA of avulsed nerve roots was lower (mean difference 0.1 [95% CI 0.07, 0.13]; < 0.001) and the MD was greater (mean difference 0.32 × 10 mm/s [95% CI 0.11, 0.53]; < 0.001). Deterministic tractography reconstructed both normal roots and root avulsions of the brachial plexus; the negative-predictive value for at least one root avulsion was 100% (95% CI 78, 100). Therefore, DTI might help visualize both normal and injured roots of the brachial plexus aided by tractography. The precision of this technique and how it relates to neural microstructure will be further investigated in a prospective diagnostic accuracy study of patients with acute brachial plexus injuries.
横断面磁共振成像（MRI）在诊断创伤性臂丛神经根撕脱伤方面的诊断准确性一般。因此，患者要么接受大型探查手术，要么接受数月的监测，以确定是否需要以及需要何种神经重建。本研究旨在开发一种3特斯拉的扩散张量成像（DTI）方案，以可视化正常神经根并识别臂丛神经的创伤性神经根撕脱伤。对7名健康成年人和12名已知（经手术探查）单侧创伤性臂丛神经根撕脱伤的成年人进行了扫描。在3特斯拉下使用单次激发回波平面成像序列采集DTI。通过确定性纤维束成像可视化臂丛神经。计算椎孔外侧隐窝中受伤和撕脱神经根的分数各向异性（FA）和平均扩散率（MD）。与健康神经根相比，撕脱神经根的FA较低（平均差异0.1[95%CI 0.07，0.13]；<0.001），MD较高（平均差异0.32×10 mm/s[95%CI 0.11，0.53]；<0.001）。确定性纤维束成像重建了臂丛神经的正常神经根和神经根撕脱伤；至少一处神经根撕脱伤的阴性预测值为100%（95%CI 78，100）。因此，DTI可能有助于在纤维束成像的辅助下可视化臂丛神经的正常和受伤神经根。在一项关于急性臂丛神经损伤患者的前瞻性诊断准确性研究中，将进一步研究该技术的精度及其与神经微观结构的关系。
