Rib Reverberation: An important New Artifact in Lung Ultrasound.

Point of care ultrasound of the lungs has emerged as a crucial tool in the evaluation of hypoxemia in critical care and hospital medicine settings. The ability to distinguish the horizontal A-line artifact from other lung pathology is essential for guiding clinical decision making. Typically, ribs and their acoustic shadows are used as anchoring anatomy to ensure visualization of pleura and parenchyma. We present a case of horizontal reverberation artifacts incidentally observed over a rib during a point of care lung ultrasound (LUS) in a 77-year-old patient with persistent hypoxic respiratory failure. Describing these reverberation artifacts caused by ribs is important to decrease the chance of misinterpretation.