Medical Physics, Department of Radiology, University Medical Center Freiburg, Freiburg, Germany.
Division of Oral and Maxillofacial Surgery, University Medical Center Freiburg, Freiburg, Germany.
Sci Rep. 2016 Mar 29;6:23301. doi: 10.1038/srep23301.
Currently, the gold standard for dental imaging is projection radiography or cone-beam computed tomography (CBCT). These methods are fast and cost-efficient, but exhibit poor soft tissue contrast and expose the patient to ionizing radiation (X-rays). The need for an alternative imaging modality e.g. for soft tissue management has stimulated a rising interest in dental magnetic resonance imaging (MRI) which provides superior soft tissue contrast. Compared to X-ray imaging, however, so far the spatial resolution of MRI is lower and the scan time is longer. In this contribution, we describe wireless, inductively-coupled intraoral coils whose local sensitivity enables high resolution MRI of dental soft tissue. In comparison to CBCT, a similar image quality with complementary contrast was obtained ex vivo. In-vivo, a voxel size of the order of 250 ∙ 250 ∙ 500 μm(3) was achieved in 4 min only. Compared to dental MRI acquired with clinical equipment, the quality of the images was superior in the sensitive volume of the coils and is expected to improve the planning of interventions and monitoring thereafter. This method may enable a more accurate dental diagnosis and avoid unnecessary interventions, improving patient welfare and bringing MRI a step closer to becoming a radiation-free alternative for dental imaging.
目前，牙科影像学的金标准是投影放射摄影或锥形束计算机断层扫描（CBCT）。这些方法快速且具有成本效益，但软组织对比度差，并使患者暴露在电离辐射（X 射线）下。需要替代的成像方式，例如软组织管理，激发了人们对牙科磁共振成像（MRI）的兴趣，它提供了更好的软组织对比度。然而，与 X 射线成像相比，到目前为止，MRI 的空间分辨率较低，扫描时间较长。在本研究中，我们描述了无线感应式口腔内线圈，其局部灵敏度能够实现高分辨率的牙科软组织 MRI。与 CBCT 相比，在离体条件下获得了具有互补对比度的相似图像质量。在体内，仅用 4 分钟即可实现约 250 × 250 × 500μm（3）的体素大小。与临床设备采集的牙科 MRI 相比，线圈敏感体积内的图像质量更好，预计将改善干预计划及其后的监测。这种方法可以实现更准确的牙科诊断，避免不必要的干预，提高患者的福利，并使 MRI 更接近成为一种无辐射的牙科影像学替代方法。
