Purpose or Case Report: The diaphragm is the major muscle used during quiet breathing and abnormalities of diaphragm motion are a source of significant morbidity, especially in infants and young children. Diaphragm motion can be either normal, decreased, absent or paradoxical. Diaphragmatic paralysis may present with unexplained respiratory distress, difficulty in weaning the patient from mechanical ventilation and persistent elevated hemidiaphragm on chest radiographs. Early diagnosis of diaphragmatic paralysis is critical to minimize prolonged ventilatory support and consider surgical plication.
Objectives:
1. To discuss our experience with diaphragm ultrasound (US) in suspected diaphragmatic paralysis.
2. To illustrate sonographic technique and protocol to perform diaphragm US.
3. To present a case-based review of the spectrum of normal and abnormal diaphragmatic motion.
Methods & Materials: Retrospective analysis of chest US exams performed for suspected diaphragm dysfunction since 2012. Sonograms were reviewed to assess B-mode, M-mode and cine images. Correlation was made with available chest radiographs and clinical findings.
Results: The spectrum of normal and abnormal diaphragm US is presented. Normal diaphragmatic motion is towards the transducer in inspiration and excursion is greater than 4 mm. The difference in hemidiaphragmatic excursions should be less than 50%. Paradoxical motion occurs when diaphragmatic motion is away from transducer in inspiration. Absent or paradoxical motion is seen in paralysis.
Conclusions: Through this exhibit, participants will gain familiarity with the techniques, protocol and interpretation of ultrasound for the evaluation of diaphragmatic motion. Traditional fluoroscopic assessment of diaphragmatic motion is no longer preferred. Sonography is the modality of choice to assess diaphragmatic motion. Its adavantages include easy portability, lack of radiation exposure, ability to visualize all portions of the diaphragm and capability of making alternate diagnoses. Utiilization of M-mode sonography technique can aid in quantification of diaphragmatic excursion. Following a dedicated protocol for diaphragm US is key to correct diagnosis.