babr xray lab test

What are X-rays?

Electromagnetic waves that penetrate matter and produce images on specialized film.

What determines how much an X-ray penetrates matter?

The density of the matter.

What does radiopaque mean?

Less X-ray penetration; appears white or light.

What does radiolucent mean?

More X-ray penetration; appears dark or black.

What are the five radiographic densities from most dense to least dense?

Barium → bone → muscle/organs → fat → air.

Which radiographic density appears darkest?

Air, because it is the least dense and most radiolucent.

How are X-rays generated?

An electric current passes through a tube between a cathode and anode; electrons from the cathode strike the anode, producing X-rays.

What are the main advantages of chest X-rays?

View internal structures; detect lung changes; monitor disease progression; assess therapy and treatment effectiveness; check tube/catheter placement.

What are common clinical indications for a chest X-ray?

Dyspnea, cough, fever, chest pain, chest trauma, aspiration, lung disease history, smoking/exposure history, abnormal ABGs/PFTs, positive TB screen, post-procedure evaluation, tube placement, CMV monitoring, sudden PIP increase, after CPR, or infectious-disease screening.

What does PA stand for?

Posteroanterior.

In which direction does the X-ray beam travel for a PA film?

Back to front.

How is a PA chest X-ray usually obtained?

Patient upright, film in front, with maximal inspiration.

What does AP stand for?

Anteroposterior.

In which direction does the X-ray beam travel for an AP film?

Front to back.

Why can the heart appear enlarged on an AP film?

The heart is farther from the film/detector, causing magnification.

What are common limitations of AP chest X-rays?

Inspiration may be limited; artifacts may be present; image quality may be poorer; the heart may appear enlarged.

What is a lateral chest X-ray?

A view taken with the patient turned so one side of the chest is against the film.

Why is the left lateral view preferred in the slides?

It provides a sharper view of the left lower lobe.

What is a lateral decubitus view?

An X-ray taken with the patient lying on the right or left side.

What is a lateral decubitus view useful for?

Evaluating suspected pneumothorax or free pleural fluid.

What happens to air and fluid in a lateral decubitus position?

Air rises; fluid falls.

According to the slides, approximately how much pleural fluid must be present to be visible on a chest X-ray?

About 100 mL or more.

What is an oblique chest X-ray view?

The patient is turned 45 degrees to the right or left, with the anterolateral chest against the film.

What is an oblique view used for?

Locating lesions, comparing bilateral lesions, and differentiating lung lesions from other structures.

What is an apical lordotic view?

A view in which the patient stands with their back toward the film and leans backward.

What does an apical lordotic view help visualize?

The lung apices and middle lung regions.

What is angiography/arteriography?

Imaging the heart and blood vessels after introducing radiopaque contrast medium.

What can pulmonary angiography help evaluate?

Thromboembolic disease of the pulmonary vasculature.

What is bronchography?

An X-ray examination of the bronchi after they are coated with radiopaque, water-soluble contrast medium.

What does bronchography outline?

The trachea, mainstem bronchi, and segmental bronchi.

What uses computer processing to create cross-sectional X-ray images?

Computed tomography (CT/CAT scan).

What is CT particularly useful for, according to the slides?

Evaluating lung disease, especially tumors.

What is fluoroscopy?

A dynamic or moving X-ray used to observe internal structures.

What is an example use of fluoroscopy in the slides?

During cardiac catheterization.

What chest structures is MRI useful for evaluating, according to the slides?

Hila/hilar lymph nodes and chest wall invasion by a Pancoast tumor.

Why is MRI not ideal for evaluating the lungs themselves?

It is not good for air-filled structures.

What does a V/Q scan compare?

Ventilation (V) and perfusion (Q).

How is a V/Q scan commonly used?

In evaluating suspected pulmonary embolism; results may be inconclusive.

What is PET used for in cancer evaluation?

Diagnosing and staging cancers and determining spread to other tissues.

How should a chest X-ray be oriented when viewed?

As if the patient is facing the viewer; the patient's right is on the viewer's left.

Where is the patient's right on a properly oriented chest X-ray?

On the viewer's left.

Where does the trachea divide into the main bronchi?

At the carina.

What major bones and landmarks are visible on a PA chest X-ray?

Clavicles, ribs, intercostal spaces, and vertebral column.

What major cardiac/mediastinal structures should be recognized on a chest X-ray?

Mediastinum, aortic knob/arch, pulmonary artery, right atrial border, left atrial region, cardiac borders, and right/left hila.

What lower chest structures should be recognized on a chest X-ray?

Right and left hemidiaphragms, costophrenic angles, cardiophrenic angles, and breast shadows.

What additional structures are seen on a lateral chest film?

Sternum, diaphragm, oblique fissure, heart/left ventricle, IVC entering the right atrium, vertebrae, and retrosternal space.

What should the retrosternal space look like on a normal lateral film?

It contains air and should appear radiolucent/dark down to where the right ventricle borders the sternum.

What does increased opacity in the retrosternal space suggest?

An abnormality.

How should vertebrae appear from superior to inferior on a normal lateral chest film?

They should become progressively darker.

What may it mean if lower vertebrae become more opaque/white on a lateral film?

Possible lower-lobe pathology.

How far should the right diaphragm normally be visible on a lateral film?

All the way to the anterior chest wall.

Why does the left diaphragm become indistinguishable where it borders the heart?

The heart and structures below the diaphragm have similar radiographic density.

What does underexposure look like?

The film appears white or hazy; vertebrae fade out before the fifth or sixth level.

What does overexposure look like?

The film appears very dark or 'burned out,' with sharp black-white contrast and prominent vertebrae.

How does distance from the film affect apparent object size?

The farther an object is from the film, the larger it appears.

How can you assess rotation on a chest X-ray?

Compare the medial ends of the clavicles with the vertebral column; they should be approximately centered/equidistant.

How many posterior ribs above the diaphragm indicate good inspiration in the slides?

About 9-10 posterior ribs.

What can poor inspiratory effort do to the apparent heart size?

Make the heart appear abnormally large.

What are examples of extraneous shadows/artifacts on a chest X-ray?

Ventilator tubing, ET/trach tubes, safety pins, gown snaps, foreign objects, EKG leads, catheters, NG tubes, surgical staples, and chest tubes.

What does shifting of anatomical structures mean?

Structures are pushed or pulled left, right, up, or down.

What conditions listed in the slides may cause anatomical shifting?

Atelectasis, fibrosis, pneumothorax, tumors/space-occupying lesions, emphysematous bullae, distended gastric air bubble, and hepatomegaly.

What is the main X-ray appearance of atelectasis?

Loss of air in part of the lung; the area may appear radiopaque/white, sometimes fluffy.

Which direction can the trachea or mediastinum shift with atelectasis?

Toward the affected area because of volume loss.

What causes obstructive atelectasis?

Gas is reabsorbed from alveoli when communication with the trachea is obstructed; causes include foreign body, tumor, or mucus plugging.

What causes compression atelectasis?

A space-occupying lesion in the thorax compresses the lung and forces air out of alveoli.

What causes relaxation/passive atelectasis?

A pleural effusion or pneumothorax eliminates contact between the parietal and visceral pleurae.

What are common X-ray findings in CHF/pulmonary edema?

Increased radiodensity, haziness from interstitial markings, prominent vascular markings (especially upper lobes), possible Kerley B lines, and sometimes pleural effusion.

What clinical findings may accompany severe pulmonary edema?

Respiratory distress, hypoxemia, and pink frothy secretions.

What X-ray findings are associated with COPD/emphysema?

Hyperinflated/enlarged lungs, flattened diaphragms, wide intercostal spaces, teardrop-shaped heart, and prominent sternal angle.

Where are foreign bodies in aspiration often seen on chest imaging?

In larger right-sided airways; the object may be radiopaque.

What can an incomplete foreign-body obstruction cause?

A ball-valve effect with distal hyperinflation/air trapping.

What is a pleural effusion?

Free fluid in the pleural space.

What is a classic chest X-ray finding in pleural effusion?

Blunting of the costophrenic angle on the affected side.

What can pleural effusion cause in the adjacent lung?

Compression atelectasis.

What imaging can help diagnose pleural effusion?

Lateral decubitus X-ray or CT.

What process is described for pulmonary fibrosis/interstitial lung disease?

An etiologic agent causes inflammation/alveolitis; alveoli or interstitial spaces fill with fluid, blood, pus, or cells; infiltrates cause haziness; fibrosis and alveolar destruction may follow.

What interstitial patterns are mentioned in the slides?

Honeycombing and ground glass.

What are common chest X-ray findings in pneumonia?

Alveolar infiltrates and consolidation; a distinct radiopaque area may appear with lobar or segmental disease; air bronchograms are often seen.

Can bacterial and viral pneumonia look similar on chest X-ray?

Yes. The slides state viral pneumonia can look the same on CXR.

What happens in a tension pneumothorax?

Air accumulates in the pleural space, pressure rises, and the underlying lung is compressed/collapses.

Which direction can the trachea and mediastinum shift in tension pneumothorax?

Toward the unaffected side.

Why is tension pneumothorax an emergency?

Increasing pleural pressure can compromise cardiovascular function.

What is subcutaneous emphysema?

Air in the soft tissues.

What does subcutaneous emphysema look like on X-ray?

Wispy, dark, marbled areas through the soft tissues.

What situations are associated with subcutaneous emphysema in the slides?

Tracheotomy, chest tubes, surgery, trauma, pneumothorax, and prolonged CMV.

What may subcutaneous emphysema precede?

A pneumothorax.

What is the key difference in mediastinal shift between atelectasis and tension pneumothorax?

Atelectasis may pull structures toward the affected side; tension pneumothorax can push them away toward the unaffected side.

What are the six main checks before interpreting a chest X-ray?

Identify PA/AP view; check exposure; assess rotation; assess inspiration; look for artifacts; check tube/catheter position.