Chest Imaging Techniques PDF

CHEST IMAGING EDGAR CHYRUSS CRISOSTOMO, MD What can you say about this Chest x-ray? How about this??? INTRO TO CHEST IMAGING The chest radiograph is the most frequently performed radiographic study. It should almost always be the first radiologic study ordered for evaluation of...

CHEST IMAGING EDGAR CHYRUSS CRISOSTOMO, MD What can you say about this Chest x-ray? How about this??? INTRO TO CHEST IMAGING The chest radiograph is the most frequently performed radiographic study. It should almost always be the first radiologic study ordered for evaluation of diseases of the thorax. INTRO TO CHEST IMAGING The natural contrast of the aerated lungs provides a window into the body to evaluate the patient for diseases involving the: Heart Lungs Pleurae tracheobronchial tree Esophagus thoracic lymph nodes thoracic skeleton chest wall upper abdomen INTRO TO CHEST IMAGING In both acute and chronic illnesses, the chest radiograph allows one to detect a disease and monitor its response to therapy. For many disease processes (eg, pneumonia and congestive heart failure) the diagnosis can be established and the disease followed to resolution with no further imaging studies. INTRO TO CHEST IMAGING There are limitations to the chest radiograph Some diseases may not be sufficiently advanced to be detected or may not result in detectable abnormalities. INTRO TO CHEST IMAGING There are limitations to the chest radiograph Other imaging methods are needed to complement the conventional chest radiograph. Other requested procedures: computed tomography (CT) positron emission tomography/computed tomography (PET/CT) radionuclide studies magnetic resonance (MR) imaging ultrasound (UTZ) CONVENTIONAL RADIOGRAPHY POSTERO-ANTERIOR and LATERAL CHEST RADIOGRAPH The simplest conventional study of the chest is a posteroanterior and lateral chest radiograph PA view or AP view? CONVENTIONAL RADIOGRAPHY POSTERO-ANTERIOR CONVENTIONAL RADIOGRAPHY LATERAL CHEST RADIOGRAPH CONVENTIONAL RADIOGRAPHY OTHER RADIOGRAPHIC PROJECTIONS ANTEROPOSTERIOR RADIOGRAPH In some clinical situations, patients may not be able to stand or sit upright for the conventional PA and lateral radiographs, and an image must be taken with the patient’s back turned to the receptor and the x-ray beam traversing the patient in an anterior-to-posterior direction. They may be taken in the x-ray department but are more commonly obtained as portable studies at the patient’s bedside such as in cases of: prolonged immobile/deconditioned patients non-cooperative pediatric populations CONVENTIONAL RADIOGRAPHY OTHER RADIOGRAPHIC PROJECTIONS LATERAL DECUBITUS Left lateral decubitus radiograph indicates that the LEFT side of the patient is dependent against the table. Right lateral decubitus radiograph indicates that the RIGHT side of the patient is dependent against the table. NUCLEAR MEDICINE PERFUSION IMAGING Nuclear medicine techniques used in evaluating diseases of the thorax include: ventilation-perfusion (V/Q) scanning tumor-seeking radiopharmaceuticals for tumor staging The V/Q scan may be used for patients with suspected pulmonary thromboembolism and who have contrast allergy or renal failure. The V/Q scan is non-invasive, and when results are negative, fewer than 10% of patients have pulmonary thromboembolism. ULTRASONOGRAPHY of the CHEST Ultrasonography is useful for imaging the soft tissues of the chest wall, heart, and pericardium, as well as fluid collections within the pleural space. Ultrasound may be used to guide thoracentesis, especially when the fluid collection is small or loculated. Large, mobile pleural effusions are usually aspirated without sonographic guidance, because these collect predictably within dependent areas of the thorax. ULTRASONOGRAPHY of the CHEST Loculated pleural fluid collections may be difficult to aspirate without guidance, and the most appropriate entrance site may be marked with sonography for easier access. Ultrasonography has been used for guidance for biopsy of peripheral lung lesions as well. Less frequently, ultrasound is utilized to guide percutaneous biopsy of mediastinal or peri-pleural lung lesions. Ultrasound-guided Thoracentesis MR IMAGING of the CHEST MRI of the thorax is most commonly used for cardiovascular imaging and for mediastinal and pulmonary parenchymal imaging. MRI is helpful when bronchogenic carcinoma is suspected of invading vascular structures, including the cardiac chambers, pulmonary arteries and veins, and the superior vena cava.  CHEST IMAGING TECHNIQUE SELECTION TECHNIQUE SELECTION RADIOGRAPH Conventional radiographs should be obtained for any patient with symptoms suggesting disease of the heart, lungs, mediastinum, or chest wall. Chest radiograph is indicated for patients with systemic diseases that have a high likelihood of secondary involvement of those structures. Eg. pneumonia , congestive heart failure, pleural effusion TECHNIQUE SELECTION RADIOGRAPH These radiographs are also used for monitoring of life-support hardware, such as central venous access catheters, nasogastric tubes, and endotracheal tubes. TECHNIQUE SELECTION RADIOGRAPH Fluoroscopy provides real-time imaging of the chest. Fluoroscopy may be used to evaluate the motion of the diaphragm in a patient with suspected diaphragmatic paralysis. TECHNIQUE SELECTION CT SCAN Because the three dimensions of the thorax are captured on a single two-dimensional chest radiograph, superimposition of structures within the thorax may result in confusing shadows. CT scan provides images without this overlap, it is frequently used to clarify confusing shadows identified on conventional radiographs. These examinations are also used to detect disease that is occult because of small size or a hidden position. Because of its wider range of density discrimination, CT can demonstrate mediastinal and chest wall abnormalities earlier than is possible with conventional chest radiography. TECHNIQUE SELECTION CT SCAN Abnormalities of hilar structures can be identified on CT scans because of the decreased overlap of the complex structures of the hilum. CT scans of the chest are routinely ordered for oncology patients, both for evaluation of the extent of disease at presentation and for monitoring response to therapy or progression of disease. CASE 1 Frontal chest radiograph shows that the right hemithorax is opaque. Signs of mass effect are present and suggest a space-occupying lesion in the right hemithorax. There is shift of the mediastinum toward the contralateral hemithorax, as evidenced by shift of the trachea and left heart border to the left. Space-occupying lesions also cause inferior displacement of the hemidiaphragm Mass effect may also widen the distance between ribs. CASE 1 In this patient, the space- occupying lesion was a large right pleural effusion resulting from tuberculous empyema. CASE 1 Axial CT scan of the chest of the same patient shows filling of the right pleural space by fluid, with compression of the right lung and displacement of the mediastinal contents into the left hemithorax. The pleural fluid in this case represented tuberculous empyema. CASE 2 Frontal chest radiograph shows that the left hemithorax is opaque. The patient has signs of volume loss within the left hemithorax. There is mediastinal shift toward the ipsilateral hemithorax, as evidenced by shift of the trachea and the right heart border into the left hemithorax. The gastric air bubble is higher in the left upper quadrant of the abdomen than is normally seen, because of elevation of the left hemidiaphragm. CASE 2 Frontal chest radiograph shows that In this patient, the left lung collapse is due to a bronchogenic carcinoma in the left main bronchus. CASE 2 The mediastinal window of the chest CT examination shows the mediastinal shift to the left and consolidation of the left lung. The lung window of the chest CT examination shows that the right lung is aerated. In this patient, the left lung collapse is due to a bronchogenic carcinoma in the left main bronchus This case exhibits the signs of volume loss, as opposed to mass effect.  Opacification of the right hemithorax occurs as a result of massive right pleural effusion Collapse is due to obstruction of the left main bronchus, resulting in atelectasis Right lung is collapsed as a result of both (airlessness) of the left lung. compression by the fluid present within the right The mass effect caused by bronchogenic CA pleural space and a loss of the negative depresses the hemithorax and displaces the intrapleural pressure that keeps the lung in close trachea, mediastinum, and diaphragm towards the mass. juxtaposition to the chest wall. Volume loss decreases the size of the The mass effect caused by large pleural effusion hemithorax, and the trachea, mediastinum, and diaphragm move toward the involved expands the hemithorax and displaces the hemithorax. trachea, mediastinum, and diaphragm away from The distance between the ribs on the the mass. abnormal side will be slightly decreased. CASE 3 The most prominent radiographic finding is coarse thickening of the brocho-vascular bundles as they radiate from the hila. Thickened bronchial walls may be identified as tram- track lines, which refers to the appearance of the nearly parallel walls of bronchi oriented longitudinally. These are present throughout both lungs and are located near the hila Both of these structures represent the thick walls of dilated bronchi (bronchiectasis). The lung volume is increased. The anterior clear space (retrosternal area) is larger and more radiolucent than normal. CASE 4 The patient has pneumococcal pneumonia (Streptococcus pneumoniae) in the right middle lobe. The opacity seen on both radiographs is best described as airspace disease. The alveoli, or airspaces, that are normally filled with air have become filled with exudate. The exudate-filled alveoli surround the bronchi, so that the air- filled bronchi are visible as radiolucent branching structures. LUNG MASS PANCOAST TUMOR TUBERCULOSIS THANK YOU!