Table 19.5.

Indications of chest fluoroscopy

Evaluation of diaphragmatic motility by deep inspiration and expiration, forced expiration	Sniff test: Sudden inspiration by the nose with closed mouth. The normal movement of the diaphragm with respiration is accentuated by sniffing. With phrenic paralysis or diaphragmatic weakness there is paradoxical movement or absence of movement
Evaluation of vascular lesions Evaluation of obstructive diseases	Muller manoeuvre: inspiration against closed mouth and nose to produce negative intrathoracic pressure. Valsalva manoeuvre: expiration against closed mouth and nose to increase intrathoracic pressure
Diagnosis of abnormal mediastinal movement	Evaluation of the mediastinal position during inspiration and expiration
Characterisation and localisation of unclear opacities on chest X-ray	Lung lesions move with respiration Differentiation of pulmonary from pleural lesions by rotating the patient
Evaluation of pulsating lesions	Vascular lesions change in volume between inspiration and expiration