Diaphragm muscle dysfunction is increasingly recognized as an important element of several diseases including neuromuscular disease, chronic obstructive pulmonary disease and diaphragm dysfunction in critically ill patients. Functional evaluation of the diaphragm is challenging. Use of volitional maneuvers to test the diaphragm can be limited by patient effort. Non-volitional tests such as those using neuromuscular stimulation are technically complex, since the muscle itself is relatively inaccessible. As such, there is a growing interest in using imaging techniques to characterize diaphragm muscle dysfunction. Selecting the appropriate imaging technique for a given clinical scenario is a critical step in the evaluation of patients suspected of having diaphragm dysfunction. In this review, we aim to present a detailed analysis of evidence for the use of ultrasound and non-ultrasound imaging techniques in the assessment of diaphragm dysfunction. We highlight the utility of the qualitative information gathered by ultrasound imaging as a means to assess integrity, excursion, thickness, and thickening of the diaphragm. In contrast, quantitative ultrasound analysis of the diaphragm is marred by inherent limitations of this technique, and we provide a detailed examination of these limitations. We evaluate non-ultrasound imaging modalities that apply static techniques (chest radiograph, computerized tomography and magnetic resonance imaging), used to assess muscle position, shape and dimension. We also evaluate non-ultrasound imaging modalities that apply dynamic imaging (fluoroscopy and dynamic magnetic resonance imaging) to assess diaphragm motion. Finally, we critically review the application of each of these techniques in the clinical setting when diaphragm dysfunction is suspected.
Medical imaging - Wikipedia
Frontiers Preclinical Ultrasound Imaging—A Review of Techniques and Imaging Applications
Doppler shift, Radiology Reference Article
Ultrasound and non-ultrasound imaging techniques in the assessment of diaphragmatic dysfunction, BMC Pulmonary Medicine
Maximum abdominal excursion assessment using an abdominal excursion measuring device: Reliability and validity of a new device for simple and quantitative assessment of respiratory function - ScienceDirect
Ultrasound Imaging Beyond Medicine: Non-Medical Applications and Uses
Diagnostics, Free Full-Text
PDF) Assessment of diaphragm motion using ultrasonography in a patient with facio-scapulo-humeral dystrophy: A case report
Assessment of diaphragmatic function by ultrasonography: Current approach and perspectives
Transrectal ultrasound: Preparation, procedure, cost, and more
Frontiers Preclinical Ultrasound Imaging—A Review of Techniques and Imaging Applications
PDF] Diaphragm sniff ultrasound: Normal values, relationship with sniff nasal pressure and accuracy for predicting respiratory involvement in patients with neuromuscular disorders
Advancements in Ultrasound
Sonography: How a Sonogram Test Works and What It Shows