Interventional procedures

The most common procedure is needle biopsy of pulmonary or mediastial nodules or masses. Under the guidance of fluoroscopy, the tip of a needle is introduced into the lesion in question, and a sample of tissue is removed for cytological or histological examination. ACT scan performed in advance facilitates assessment of the site of puncture and the depth. Pneumothorax and haemoptysis may occur after such procedures, most often with spontaneous regression.

Free pleural fluid is evacuated without use of imaging techniques. If the fluid is encapsulated, evacuation under guidance of ultrasound is advised.

Intravascular interventional procedures in the thorax, for example embolization, are carried out in both the pulmonary and bronchial circulations. In the pulmonary circulation there may be arterio-venous malformations which shunt non-oxygenated blood in the pulmonary arteries directly into the pulmonary veins. On chest radiographs, these vascular malformations are seen as rounded opacities with afferent and efferent linear, vessel-like structures. Pulmonary angiography verifies the diagnosis. With the guide-wire, small, occluding metal coils can be pushed out through the catheter to the supplying arteries. The size of the spiral must be such that it does not slip through to the pulmonary veins, and thus into the systemic circulation, with a risk of cerebral embolism.

Severe hemoptysis can be mapped and treated by bronchial arteriography and embolization. This is especially useful in patients with cystic fibrosis.

The risk associated with this type of embolization is that a spinal artery may arise from the bronchial artery, and thus become occluded at the same time. This type of procedure should only be carried out by radiologists with long experience.

Alf Kolbenstvedt, Arnulf Skjennald and Charles B. Higgins