Imaging biomarkers in axial spondyloarthritis (axSpA) are currently the most specific biomarkers for the diagnosis of this condition. Despite advances in imaging, from plain radiographs-which detect only damage-to magnetic resonance imaging (MRI)-which identifies disease activity and structural change-there are still many challenges that remain. Imaging in sacroiliitis is characterized by active and structural changes. Current classification criteria stress the importance of bone marrow edema (BME); however, BME can occur in various diseases, mechanical conditions, and healthy individuals. Thus, the identification of structural lesions such as erosion, subchondral fat, backfill, and ankylosis is important to distinguish from mimics on differential diagnosis. Various imaging modalities are available to examine structural lesions, but computed tomography (CT) is considered the current reference standard. Nonetheless, recent advances in MRI allow for direct bone imaging and the reconstruction of CT-like images that can provide similar information. Therefore, the ability of MRI to detect and measure structural lesions is strengthened. Here, we present an overview of the spectrum of current and cutting-edge techniques for SpA imaging in clinical practice; namely, we discuss the advantages, disadvantages, and usefulness of imaging in SpA through radiography, low-dose and dual-energy CT, and MRI. Cutting-edge MRI sequences including volumetric interpolated breath-hold examination, ultrashort echo time, zero echo time, and deep learning-based synthetic CT that creates CT-like images without ionizing radiation, are discussed. Imaging techniques allow for quantification of inflammatory and structural lesions, which is important in the assessment of treatment response and disease progression. Radiographic damage is poorly sensitive to change. Artificial intelligence has already revolutionized radiology practice, including protocolization, image quality, and image interpretation.

中文翻译：

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脊柱关节炎未满足的需求：中轴型脊柱关节炎的成像。


中轴型脊柱关节炎 （axSpA） 的影像学生物标志物是目前诊断这种情况的最特异性生物标志物。尽管成像取得了进步，但从仅检测损伤的平片到识别疾病活动和结构变化的磁共振成像 （MRI），仍然存在许多挑战。骶髂关节炎的影像学检查以活动性和结构性改变为特征。目前的分类标准强调骨髓水肿 （BME） 的重要性;然而，BME 可以发生在各种疾病、机械条件和健康个体中。因此，识别结构性病变（例如糜烂、软骨下脂肪、回填和强直）对于鉴别诊断中的类似物很重要。有多种影像学检查方式可用于检查结构性病变，但计算机断层扫描 （CT） 被认为是当前的参考标准。尽管如此，MRI 的最新进展允许直接进行骨成像和重建可以提供类似信息的 CT 样图像。因此，MRI 检测和测量结构病变的能力得到加强。在这里，我们概述了临床实践中 SpA 成像的当前和前沿技术范围;即，我们讨论了通过 X 线照相、低剂量和双能 CT 以及 MRI 对 SpA 进行成像的优缺点和有用性。讨论了尖端的 MRI 序列，包括体积插值屏气检查、超短回声时间、零回声时间和基于深度学习的合成 CT，该 CT 可在没有电离辐射的情况下创建类似 CT 的图像。 影像学技术可以量化炎症和结构病变，这对于评估治疗反应和疾病进展非常重要。影像学损伤对变化的敏感性较差。人工智能已经彻底改变了放射学实践，包括协议化、图像质量和图像解释。