Buttar Simran, Cooper Denrick, Olivieri Patrick, Barca Michael, Drake Aaran B, Ku Melvin, Rose Gabriel, Siadecki Sebastian D, Saul Turandot
Department of Emergency Medicine, Division of Emergency Ultrasound, Mount Sinai St. Luke's Hospital, Mount Sinai West Hospital, New York, New York.
J Emerg Med. 2017 Aug;53(2):241-247. doi: 10.1016/j.jemermed.2017.01.054. Epub 2017 Mar 31.
Although air has traditionally been considered a barrier to sonographic imaging, when encountered in unusual settings it can serve as an important indicator of various pathologic states as well. Clinician recognition and thorough understanding of the characteristic pattern of artifacts generated by air are critical for making a number of important diagnoses.
We present five emergency department cases in which air was visualized in a pathologic location. Pneumothorax, pneumoperitoneum, necrotizing fasciitis, or Fournier's gangrene, and subcutaneous emphysema and pneumomediastinum, can be rapidly and easily identified on ultrasound by the presence of air artifacts. The relevant sonographic findings are described and discussed in this article. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Due to its inherent impedance mismatch with other human tissues, air has a characteristic appearance on ultrasound that includes irregular hyperechoic structures, "dirty shadowing," A-lines, and decreased visualization of deeper structures. Knowledge of the sonographic appearance of air artifacts can assist the physician in making a diagnosis, selecting appropriate additional imaging, and enlisting specialist consultation.
尽管传统上空气被视为超声成像的障碍，但在异常情况下遇到空气时，它也可作为各种病理状态的重要指标。临床医生识别并透彻理解由空气产生的伪像的特征模式对于做出许多重要诊断至关重要。
我们展示了五例在病理位置可见空气的急诊科病例。气胸、气腹、坏死性筋膜炎或福尼尔坏疽以及皮下气肿和纵隔气肿，可通过超声检查发现空气伪像而快速、轻松地识别。本文描述并讨论了相关的超声检查结果。为什么急诊医生应该了解这一点？：由于空气与其他人体组织存在固有的阻抗不匹配，空气在超声上具有特征性表现，包括不规则的高回声结构、“脏污伪像”、A线以及深部结构显示不清。了解空气伪像的超声表现可帮助医生进行诊断、选择合适的额外影像学检查以及寻求专科会诊。
