"We describe an ultrasound (US)-guided technique for needle examination of the diaphragm and report a case in which the adjuvant use of diagnostic US in conjunction with electrophysiologic studies provided additional information regarding the motion of the diaphragm in a patient who was a potential candidate for phrenic nerve pacing."

"A 68-year-old man underwent cervical spine decompressive surgery for progressive myelopathy....The patient was transferred to our tertiary care facility 2 months after surgery for comprehensive inpatient rehabilitation and weaning from the ventilator."

"Videofluoroscopy of the diaphragm showed no motion of the left hemidiaphragm but some motion of the right hemidiaphragm."

"In order to determine the potential role of phrenic nerve pacing, electrophysiologic studies were performed in conjunction with ultrasonography to better define the pathophysiology of the patient’s respiratory failure."

"These studies were interpreted as showing evidence of a complete neurogenic lesion of the left diaphragm and a severe partial lesion of the right diaphragm, with the lesion most likely located at the level of the anterior horn cells. Based on the electrophysiologic findings, it was determined the patient was not a candidate for phrenic nerve pacing."

Boon AJ, Alsharif KI, Harper CM, Smith J. "Ultrasound-Guided Needle EMG of the Diaphragm: Technique Description and Case Report" Muscle & Nerve; pp 1623-26, Vol. 38, No. 6, December 2008.