Holzgrefe Russell E, Wagner Eric R, Singer Adam D, Daly Charles A
Department of Orthopaedic Surgery, Emory University, Atlanta, GA.
Department of Radiology, Emory University, Atlanta, GA.
J Hand Surg Am. 2019 Dec;44(12):1066-1079. doi: 10.1016/j.jhsa.2019.06.021. Epub 2019 Oct 2.
Advanced imaging is increasingly used by upper extremity surgeons in the diagnosis and evaluation of peripheral nerve pathology. Ultrasound and magnetic resonance neurography (MRN) have emerged as the most far-reaching modalities for peripheral nerve imaging and often provide complimentary information. Technology improvements allow better depiction of the peripheral nervous system, allowing for more accurate diagnoses and preoperative planning. The purpose of this review is to provide an overview of current modalities and expected advances in peripheral nerve imaging with a focus on practical applications in the clinical setting. Ultrasound is safe, inexpensive, and readily available, and allows dynamic imaging with high spatial resolution as well as immediate evaluation of the contralateral nerve for comparison. It is primarily limited by its dependency on skilled operators and soft tissue contrast. The spatial evaluation of the perineural environment, fascicular echostructure, and nerve diameter are features of particular use in the diagnosis and treatment of nerve tumors, compressive lesions, and nerve trauma. Sonoelastrography has shown promise as a useful adjunct to standard sonographic imaging. MRN refers to the optimization of magnetic resonance image sequences and technology for visualization and contrasting nerves from surrounding structures. MRN provides excellent soft tissue contrast, depicts the entire nerve in 3 dimensions, allows for early evaluation of downstream muscle injury, and functions without operator dependency limits. Images provide details of nerve anatomic relationships, congruency, size, fascicular pattern, local and intrinsic fluid status, and contrast enhancement patterns, making MRN particularly useful in the setting of trauma, tumor, compressive lesions, and evaluation of brachial plexus injuries. Advances in MR volume and cinematic rendering software, magnet and coil technology, nerve-specific contrast media, and diffusion-weighted and tensor imaging will likely continue to expand the clinical application and indications for MRN.
上肢外科医生在诊断和评估周围神经病变时越来越多地使用先进成像技术。超声和磁共振神经造影（MRN）已成为周围神经成像应用最广泛的方式，且常常能提供互补信息。技术的进步使周围神经系统的显示更加清晰，有助于更准确的诊断和术前规划。本综述的目的是概述周围神经成像的当前方式和预期进展，重点关注其在临床环境中的实际应用。超声安全、廉价且易于获取，能够进行具有高空间分辨率的动态成像，并可立即对侧神经进行评估以作对比。其主要局限性在于依赖技术熟练的操作人员以及软组织对比度。对神经周围环境、束状回声结构和神经直径的空间评估，在神经肿瘤、压迫性病变和神经创伤的诊断与治疗中具有特别的用途。超声弹性成像已显示出有望成为标准超声成像的有用辅助手段。MRN是指优化磁共振图像序列和技术，以实现神经与周围结构的可视化和对比。MRN提供出色的软组织对比度，能在三维空间中描绘整个神经，可早期评估下游肌肉损伤，且不受操作人员依赖的限制。图像提供神经解剖关系、一致性、大小、束状模式、局部和内在液体状态以及对比增强模式的详细信息，这使得MRN在创伤、肿瘤、压迫性病变以及臂丛神经损伤评估方面特别有用。MR容积和电影渲染软件、磁体和线圈技术、神经特异性造影剂以及扩散加权和张量成像的进展，可能会继续扩大MRN的临床应用和适应证。
