Reduced definition of the right heart border is typically associated with right middle lobe consolidation.The heart borders may become difficult to distinguish from the lung fields as a result of pathology which increases the opacity of overlying lung tissue: The left ventricle makes up most of the left heart border.The right atrium makes up most of the right heart border.Inspect the borders of the heart which should be well defined in healthy individuals: Cardiomegaly can develop for a wide variety of reasons including valvular heart disease, cardiomyopathy, pulmonary hypertension and pericardial effusion. This rule only applies to PA chest X-rays (as AP films exaggerate heart size), so you should not draw any conclusions about heart size from an AP film.Ĭardiomegaly is said to be present if the heart occupies more than 50% of the thoracic width on a PA chest X-ray. a cardiothoracic ratio of less than 0.5). In a healthy individual, the heart should occupy no more than 50% of the thoracic width (e.g. Pleural thickening in the context of mesothelioma 2 The complete absence of lung markings should raise suspicion of a pneumothorax.Increased airspace shadowing in a given area of a lung field may indicate pathology (e.g. Some lung pathology causes symmetrical changes in the lung fields, which can make it more difficult to recognise, so it’s important to keep this in mind (e.g.Compare each zone between lungs, noting any asymmetry (some asymmetry is normal and caused by the presence of various anatomical structures e.g.Inspect the lung zones ensuring that lung markings are present throughout.the left lung has three zones but only two lobes). These zones do not equate to lung lobes (e.g.When interpreting a chest X-ray you should divide each of the lungs into three zones, each occupying one-third of the height of the lung.by an enlarging soft tissue mass) or pulled (e.g. You should inspect for evidence of the hilar being pushed (e.g. Unilateral/asymmetrical enlargement may be due to underlying malignancy.Ībnormal hilar position can also be due to a range of different pathologies.Bilateral symmetrical enlargement is typically associated with sarcoidosis. Hilar enlargement can be caused by a number of different pathologies: lung tumour or enlarged lymph nodes).Ĭauses of hilar enlargement or abnormal position When this is lost, consider the possibility of a lesion here (e.g. The hilar point is also a very important landmark anatomically it is where the descending pulmonary artery intersects the superior pulmonary vein. The hilar are usually the same size, so asymmetry should raise suspicion of pathology. The left hilum is often positioned slightly higher than the right, but there is a wide degree of variability between individuals. The hilar consist of the main pulmonary vasculature and the major bronchi.Įach hilar also has a collection of lymph nodes which aren’t usually visible in healthy individuals. Carina and bronchi (normal CXR) Hilar structures As a result of this difference in size and orientation, it is more common for inhaled foreign objects to become lodged in the right main bronchus.ĭepending on the quality of the chest X-ray you may be able to see the main bronchi branching into further subdivisions of bronchi. The right main bronchus is generally wider, shorter and more vertical than the left main bronchus. The carina is an important landmark when assessing nasogastric (NG) tube placement, as the NG tube should bisect the carina if it is correctly placed in the gastrointestinal tract. On appropriately exposed chest X-ray, this division should be clearly visible. The carina is cartilage situated at the point at which the trachea divides into the left and right main bronchus. Pleural effusion with tracheal deviation 2 Carina and bronchi
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |