Fig. 1From: Phrenic nerve stimulation prevents diaphragm atrophy in patients with respiratory failure on mechanical ventilationUltrasound linear probe orientation (a) and view of the diaphragm (b) identified as a 3-layer structure comprised of two hyperechoic lines representing the pleural and peritoneal membranes and a middle hypoechoic layer representing the diaphragm muscle itselfBack to article page