Chest Imaging.pdf

Chest Imaging Imaging modaleties Plain X-rays Computed Tomography Magnetic Resonance Imaging Ultrasound  X-rays Imaging Postero-anterior View Lateral View Computed Tomography Ultrasound MRI  Pneumonia Definition: Lung consolidation with lobar distribution. Fea...

Chest Imaging Imaging modaleties Plain X-rays Computed Tomography Magnetic Resonance Imaging Ultrasound  X-rays Imaging Postero-anterior View Lateral View Computed Tomography Ultrasound MRI  Pneumonia Definition: Lung consolidation with lobar distribution. Features of Consolidation Opacity is confined to a lobe or segment or part of a segment of the lung & limited by fissures Retained normal lung volume. Air-bronchogram within the affected area (characteristic). Air within the bronchi is radiolucent, the surrounding lung field is filled with fluid (consolidated) and therefore radiopaque  LUNG COLLAPSE (ATELECTASIS) Definition Partial or complete loss of lung volume (reduced volume of air in the lung) Mechanisms of Collapse 1- Obstructive collapse - Bronchial obstruction with alveolar gas beyond that level being absorbed by blood in the pulmonary capillary. -This occurs in strictures, mucus plugs, foreign body, or bronchial rupture, bronchogenic carcinoma. 2. Non-obstructive collapse The lung is compressed medially and the air within it is eliminated. May be caused by pleural mass, fluid or air A. Direct Signs of Lung Collapse 1. Displacement of interlobar fissures 2. Loss of aeration 3. Vascular changes Crowding of vessels 4. Bronchial crowding and re-arrangement B. Indirect Signs of Lung Collapse 1. Elevated hemidiaphragm. 2. Mediastinal shift 6.Rib crowding. 7.Compensatory hyperinflation  Tuberculosis Radiographic Features: 1. Lobar consolidation. (The Ghons focus): The area of the peripheral lung adjacent to the sub-pleural area where the organism settles may become consolidated. 2. Enlarged lymph nodes 4. Pleural effusion 6. Pneumothorax 7. Miliary tuberculosis: multiple pinpoint soft tissue opacities of 1 – 2 mm in diameter. 9. Tuberculoma: solitary, well-defined pulmonary nodule of 0.5 – 5 cm in diameter. 10. Destroyed lung syndrome: fibrosis, cystic changes, lung collapse and eventually destruction of the lung.  Emphysema Definition: Increase size of the air spaces distal to the terminal bronchioles with dilatation and destruction of their walls. Radiological Features 1. Hyperinflation 2. Reduction of peripheral pulmonary vasculature 3. Flattened diaphragm 7. Long narrow heart 9. Bullae. Round or oval translucencies varying in size from 1 cm to very large size found throughout the lung and are peripherally situated. Bronchogenic carcinoma Radiological Features. 1. Solitary or multiple pulmonary nodules 2. lung masses. 3. Cavitating lung mass 4. Mediastinal lymphadenopathy 5. Pleural thickening / Pleural effusion Malignant Pulmonary Tumors Cavitating Pancost tumor at squamous cell the apex of the carcinoma left lung Pumonary metastasis  Pleural Pathology 1) Pleural Effusion Def: Accumulation of fluid (exaudate-blood-pus) within the pleural cavity between the visceral & parietal pleura. Mild effusion cause just obliteration of the costo- phrenic Moderate pleural effusion angle Massive pleural effusion Encysted pleural effusion  2) Pneumothorax Def: Accumulation of air within the pleural cavity Increased lucency of the involved hemithorax (devoid of lung markings). Visualization of the edge of the collapsed lung  3)Hydro-pneumothorax Def: accumulation of air & fluid within the pleural cavity forming air/fluid level 4)Pleural Neoplasm Localized or diffuse pleural involvement. Focal pleural tumors include fibrous tumors , lipomas & liposarcomas Diffuse involvement include malignant mesothelioma and metastases. Localized pleural tumor Diffuse pleural tumor