Bedside sonographic evaluation of the diaphragm in ventilator dependent patients with amyotrophic lateral sclerosis. A report of two cases.

Amyotrophic lateral sclerosis (ALS) is a neurodegenerative disease with progressive and inexorable loss of bulbar and limb functions. Respiratory muscle weakness and failure is a common complication late in the course of disease. Bedside ultrasonography of the diaphragm was done in two ventilator dependent patients with ALS. Thickness of the diaphragm was markedly reduced during both end expiration and end of deep inspiration. The degree of diaphragmatic thickening was also significantly reduced. The diaphragmatic excursion during deep inspiration was sub-optimal. The findings were consistent with diaphragmatic atrophy and paralysis. Sonography of the diaphragm can be a useful non-invasive bedside tool for the diagnosis and follow up of diaphragmatic involvement in patients with amyotrophic lateral sclerosis.