12.12.12 Chest radiographs

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Normal locations

    • Right diaphragm 1.5 cm higher than left

      • => Double-diaphragm sign on lateral film

    • Left hilum 1.5 cm higher

Anterior mediastinal mass

    • T - Thymoma

    • T - Thyroid

    • T - Teratoma

    • T - Terrible lymphoma

Atelectasis

    • Causes

      • Cancer

      • Mucous plug

      • Trauma

    • Appearance

      • VEIL-LIKE OPACITY

      • Diaphragm raised / tented

      • Hilum drawn up

    • Left upper lobe

      • Colapses anteriorly

      • Mediastinum shifted

      • Left hilum raised

      • Raised and tented left diaphragm, pulled up by pulmonary ligament

    • Luftsichel Sign

        • Lucency outlining the aortic arch on frontal view

        • Indicates Left upper lobe collapse

        • Occurs as a result of the superior segment of the left lower lobe migrating superiorly and abutting the aortic knob due to volume loss of the left upper lobe

    • Right upper lobe

      • Golden S sign

      • Seen in the right lung as a distorted minor fissure, whose lateral aspect is concave inferiorly and whose medial aspect is convex inferiorly

    • Right middle lobe

      • Silhouette sign - Can't distinguish right heart border

    • Right or left lower lobe

      • Sail sign

Interstitial vs Alveolar oedema

    • Quite difficult to distinguish!

    • Alveolar is "cotton-wool" / fluffy

    • Interstitial may be linear, nodular, reticulonodular

    • Causes of interstitial oedema

      • infectious causes, e.g.: non-tuberculous mycobacteria & certain fungal infections

      • occupational causes, e.g.: asbestos & silica

      • drug reactions, e.g.: methotrexate & amiodarone

      • neoplastic causes, e.g.: metastatic cancer, bronchoalveolar cell carcinoma (a form of lung cancer)

      • radiation pneumonitis

      • hypersensitivity pneumonitis

      • rheumatologic diseases

        • systemic lupus erythematosis

        • rheumatoid arthritis

        • scleroderma

        • mixed connective tissue disease

        • polymyositis

      • Diseases of unknown cause, e.g.: sarcoidosis, Langerhan's cell granulomatosis (eosinophilic granuloma; histiocytosis X), lymphangioleiomyomatosis

      • Idiopathic pulmonary fibrosis

    • Causes of alveolar oedema

      • Pneumonitis

      • Pulmonary contusion

      • Pulmonary oedema

      • Aspiration

  • http://www.wikiradiography.com/page/Interstitial+vs+Alveolar+Lung+Patterns

PE signs

    • Westermark’s sign - focal oligemia

    • Palla’s sign - a prominent right descending pulmonary artery

Pneumomediastinum

    • Oesophageal rupture, for example in Boerhaave syndrome

    • Asthma or other conditions leading to alveolar rupture

    • Bowel rupture, where air in the abdominal cavity tracts up into the chest.

    • Mycoplasma pneumoniae pneumonia

    • Obesity

Notes

    • Technically, consolidation refers to any fluid, not just from infection

    • Bullae/blebs bursting => pneumothorax

    • Cavitating lesion - Lucent border, opacity within