Pulmonary scan

Abstract

For many years it was believed that due to their air content, it was not possible to examine the lungs using ultrasound. However, notwithstanding the wealth of literature produced over the last ten years has shown the considerable potential of ultrasound in diagnosing pulmonary disease, pulmonary ultrasound is still a little known and rarely used technique. Chest radiography has long been and still largely remains the diagnostic method of choice in lung disease. However, it is well known that, especially in emergency situations, radiological imaging is unsatisfactory as regards the standard required, with consequent further difficulties in interpreting the clinical situation. Chest x-rays performed in emergency departments frequently involve non-cooperative and/or bed-ridden patients. It is not always possible to obtain a lateral projection and the postero-anterior projection is performed in orthostatic conditions. In addition to these limits deriving from pictures obtained in non-optimal conditions, there are also intrinsic limits, such as an opaque hemithorax cannot always be precisely attributed to parenchymal or pleural pathology and widespread expansion of the interstitial space may mean many things, from pulmonary stasis to the great variety of interstitial diseases. Pulmonary CT is considered a diagnostic gold standard and yet it entails the transportation of patients that are often instable, exposure to high doses of ionising radiation (the equivalent of 100-200 chest x-rays), high costs and risks connected to iodate agents. Pulmonary ultrasound would appear promising especially in emergency medicine, as particularly in such contexts the immediate availability of diagnostic means, the simplicity of execution and interpretation of the images are all important.