How do you interpret a chest X-ray. What are the key steps in analyzing lung zones. How can you identify consolidation and air bronchograms. What are common causes of unilateral and bilateral lung abnormalities. How do you differentiate between various lung pathologies on X-ray.

Essential Techniques for Chest X-Ray Analysis

Chest X-rays (CXRs) are fundamental diagnostic tools in medicine, providing crucial insights into lung health and potential abnormalities. To accurately interpret a CXR, healthcare professionals must follow a systematic approach:

• Compare left and right upper, middle, and lower lung zones
• Identify asymmetry and determine which side is abnormal
• Contrast areas of concern with surrounding lung tissue
• Remember that increased whiteness doesn’t always indicate abnormality
• Consider that many lung diseases present bilaterally and symmetrically

By adhering to these principles, clinicians can enhance their ability to detect and characterize lung abnormalities accurately.

Understanding Lung Zones and Density Variations

Proper assessment of lung zones is crucial for identifying abnormalities on chest X-rays. Healthcare professionals should:

1. Divide each lung into upper, middle, and lower zones
2. Compare corresponding zones on both sides
3. Look for asymmetry in lung density

Abnormal whiteness indicates increased density, while abnormal blackness suggests decreased density. When asymmetry is detected, the next step is determining which side is abnormal. Often, an area that differs from the surrounding lung tissue on the same side is likely to be abnormal.

Is increased whiteness always indicative of pathology?

No, increased whiteness is not always indicative of pathology. In some cases, the whiter side may be normal, while the darker side represents an abnormality such as hyperinflation or a large bulla. This highlights the importance of considering clinical context and comparing findings with the rest of the lung tissue.

Recognizing Consolidation and Its Significance

Consolidation occurs when alveoli and small airways fill with dense material, resulting in a white appearance on chest X-rays. It’s crucial to understand that consolidation doesn’t always signify infection. The small airways can fill with various substances:

• Pus (as in pneumonia)
• Fluid (pulmonary edema)
• Blood (pulmonary hemorrhage)
• Cells (cancer)

These different causes can present similarly on X-rays, emphasizing the importance of clinical information in reaching an accurate diagnosis.

How can you distinguish between different types of consolidation?

Distinguishing between different types of consolidation often requires a combination of radiological findings and clinical information. While the X-ray appearance may be similar, factors such as patient history, symptoms, laboratory results, and physical examination findings can help narrow down the differential diagnosis. In some cases, additional imaging studies like CT scans may be necessary for definitive diagnosis.

Identifying Air Bronchograms: A Key Diagnostic Sign

Air bronchograms are characteristic signs of consolidation on chest X-rays. They appear as dark lines or branching patterns within areas of increased lung density. This phenomenon occurs when:

1. Lung tissue becomes consolidated and appears white on X-ray
2. Larger airways remain patent and filled with air
3. The air-filled bronchi contrast against the dense surrounding tissue

Recognizing air bronchograms is crucial for confirming the presence of consolidation and differentiating it from other causes of increased lung density, such as pleural effusions or atelectasis.

Can air bronchograms be seen in conditions other than consolidation?

While air bronchograms are most commonly associated with consolidation, they can occasionally be seen in other conditions. For example, they may be visible in some cases of interstitial lung disease or fibrosis, where the increased density of the lung parenchyma allows visualization of air-filled bronchi. However, the appearance and distribution of air bronchograms in these cases often differ from those seen in typical consolidation.

Unilateral Lung Abnormalities: Detection and Differential Diagnosis

Unilateral lung abnormalities on chest X-rays can provide valuable diagnostic clues. Careful comparison of lung zones is essential for detecting smaller, localized abnormalities that might otherwise be overlooked. Common unilateral findings include:

• Focal consolidation
• Solitary pulmonary nodules
• Cavitary lesions
• Localized areas of hyperinflation

When evaluating unilateral abnormalities, consider the following differential diagnoses:

1. Pneumonia
2. Lung cancer
3. Tuberculosis
4. Lung abscess
5. Septic emboli
6. Fungal infections
7. Granulomatosis with polyangiitis

How do you approach the diagnosis of a unilateral cavitary lesion?

When encountering a unilateral cavitary lesion on a chest X-ray, consider the following approach:

1. Assess the cavity’s characteristics (size, wall thickness, surrounding infiltrate)
2. Review the patient’s clinical history and risk factors
3. Consider common causes such as lung abscess, tuberculosis, and cancer
4. Evaluate for less common etiologies like septic emboli or fungal infections
5. Recommend additional imaging or diagnostic tests as needed

Remember that clinical context is crucial in narrowing down the differential diagnosis and guiding further management.

Bilateral Lung Abnormalities: Challenges and Diagnostic Strategies

Bilateral lung abnormalities present unique challenges in chest X-ray interpretation. When both lungs are affected, side-to-side comparison becomes less useful, and familiarity with normal lung parenchyma appearances becomes crucial. Common bilateral findings include:

• Diffuse interstitial lung disease
• Pulmonary edema
• Bilateral pneumonia
• Metastatic lung disease
• Sarcoidosis

When evaluating bilateral abnormalities, consider the following factors:

1. Distribution pattern (upper vs. lower lung predominance)
2. Symmetry or asymmetry of the findings
3. Presence of nodules, reticular patterns, or ground-glass opacities
4. Associated findings such as pleural effusions or lymphadenopathy

How can you differentiate between cardiogenic and non-cardiogenic pulmonary edema on chest X-ray?

Differentiating between cardiogenic and non-cardiogenic pulmonary edema on chest X-ray involves assessing several key features:

• Cardiogenic edema:
  • Central distribution of opacities
  • Enlarged cardiac silhouette
  • Prominent pulmonary vasculature
  • Pleural effusions (often bilateral)
• Non-cardiogenic edema:
  • More peripheral distribution of opacities
  • Normal cardiac size
  • Air bronchograms may be more prominent
  • Pleural effusions less common or absent

Clinical history and additional tests such as echocardiography may be necessary for definitive diagnosis.

Interpreting Low-Density Lung Abnormalities

While increased lung density often draws attention on chest X-rays, areas of decreased density (appearing darker) can also indicate significant pathology. Common causes of unilateral or focal low-density abnormalities include:

• Pneumothorax
• Large bullae
• Emphysema
• Bronchiectasis

When evaluating areas of decreased lung density, consider the following:

1. Location and extent of the low-density area
2. Presence of visible lung markings within the area
3. Associated findings such as mediastinal shift or rib spreading
4. Patient’s clinical history and risk factors

How do you distinguish between a large bulla and a pneumothorax on chest X-ray?

Distinguishing between a large bulla and a pneumothorax can be challenging, but several features can help:

• Bulla:
  • Curved or rounded inner margin
  • May contain visible lung markings
  • Often associated with other emphysematous changes
  • No mediastinal shift unless very large
• Pneumothorax:
  • Sharp, linear pleural line
  • No lung markings beyond the pleural line
  • May cause mediastinal shift if large
  • Can be associated with rib fractures or other trauma

In some cases, CT imaging may be necessary for definitive diagnosis, especially with large bullae that mimic pneumothoraces.

Advanced Techniques and Considerations in Chest X-Ray Interpretation

As healthcare professionals gain experience in chest X-ray interpretation, they can employ advanced techniques to enhance their diagnostic accuracy:

1. Silhouette sign: Loss of normal organ borders due to adjacent opacities
2. Spine sign: Assessing vertebral body visibility to detect retrocardiac abnormalities
3. Deep sulcus sign: Indicating a small pneumothorax on supine films
4. Lateral decubitus views: Useful for detecting small pleural effusions or pneumothoraces
5. Comparison with prior studies: Essential for identifying subtle changes over time

Additionally, consider the following factors when interpreting chest X-rays:

• Patient positioning and technique
• Presence of medical devices or foreign bodies
• Limitations of projectional radiography
• Need for additional views or advanced imaging in complex cases

How can the silhouette sign aid in localizing lung abnormalities?

The silhouette sign helps localize lung abnormalities by demonstrating the loss of normal organ borders when an adjacent structure has similar density. For example:

• Right middle lobe infiltrate: Obliteration of the right heart border
• Left lower lobe consolidation: Loss of the left hemidiaphragm outline
• Right upper lobe mass: Obscuration of the right superior mediastinal border

By recognizing which borders are obscured, radiologists can more accurately determine the location and extent of lung abnormalities.

In conclusion, mastering chest X-ray interpretation requires a systematic approach, attention to detail, and integration of clinical information. By understanding normal anatomical relationships, recognizing key radiographic signs, and considering a broad differential diagnosis, healthcare professionals can maximize the diagnostic value of this essential imaging modality. Continuous learning and experience are crucial for developing expertise in chest X-ray interpretation, ultimately leading to improved patient care and outcomes.

Chest X-ray Abnormalities – Lung abnormalities

Chest X-ray Abnormalities – Lung abnormalities

Key points

• Compare the left and right upper, middle and lower lung zones
• Decide which side is abnormal
• Compare an area of abnormality with the rest of the lung on the same side
• The whiter side is not always the abnormal side
• Remember many lung diseases are bilateral and symmetrical

Lung zones

Assess the lungs by comparing the upper, middle and lower lung zones on the left and right. Asymmetry of lung density is represented as either abnormal whiteness (increased density), or abnormal blackness (decreased density). Once you have spotted asymmetry, the next step is to decide which side is abnormal. If there is an area that is different from the surrounding ipsilateral lung, then this is likely to be the abnormal area.

Consolidation

If the alveoli and small airways fill with dense material, the lung is said to be consolidated. It is important to be aware that consolidation does not always mean there is infection, and the small airways may fill with material other than pus (as in pneumonia), such as fluid (pulmonary oedema), blood (pulmonary haemorrhage), or cells (cancer). They all look similar and clinical information will often help you decide the diagnosis.

Air bronchogram

If an area of lung is consolidated it becomes dense and white. If the larger airways are spared, they are of relatively low density (blacker). This phenomenon is known as air bronchogram and it is a characteristic sign of consolidation.

Consolidation with air bronchogram

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Consolidation with air bronchogram

• The left middle zone is white
• Dark lines through the area of white are a good example of air bronchogram

Clinical information

• The patient had a high temperature and a productive cough

Diagnosis

• Pneumonia – consolidation with pus

Differential diagnosis of consolidation

• Pneumonia – airways full of pus
• Cancer – airways full of cells
• Pulmonary haemorrhage – airways full of blood
• Pulmonary oedema – airways full of fluid

Small lung zone abnormalities

Careful comparison of the lung zones can lead to noticing smaller abnormalities which may otherwise be ignored.

Unilateral middle zone abnormality

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Unilateral middle zone abnormality

• The middle zones are asymmetrical
• There is a small irregular opacity on the right
• This opacity contains a dark area – cavity
• Other areas of the lungs are normal

Clinical information

• This patient had a history of intravenous drug abuse and presented with a high fever

Diagnosis

• Septic embolus

Differential diagnosis of lung cavities

• Lung abscess – TB, Klebsiella or Staph aureus
• Lung cancer
• Septic embolus – infected thrombus
• Fungal infection – if immunocompromised
• Granulomatosis with polyangiitis

Bilateral lung abnormalities

Comparing sides does not always give the answer. The lungs may be abnormal on both sides and so awareness of the normal appearances of lung parenchyma becomes more important.

Bilaterally abnormal lung zones

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Bilaterally abnormal lung zones

• Multiple bilateral lung nodules
• Symmetrical distribution
• More nodules at the lung bases

Clinical information

• Shortness of breath, weight loss and clinically suspected underlying malignancy

Diagnosis

• Pulmonary metastases

Unilateral low density

If there is asymmetry of the lungs, sometimes it is the dark (less dense) area that is abnormal.

Unilateral black lower zone

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Unilateral black lower zone

• Asymmetrical lower zones
• Left darker than right
• Lung hyperexpansion

Clinical information

• Chronic smoker with increasing shortness of breath

Diagnosis

• Chronic obstructive pulmonary disease with a large left lower zone lung bulla

Page author:
Dr Graham Lloyd-Jones BA MBBS MRCP FRCR – Consultant Radiologist –
Salisbury NHS Foundation Trust UK
(Read bio)

Last reviewed:
July 2019

X-rays – what patients need to know

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Frequently asked questions

» What are X rays and what do they do?
» How safe are X rays?
» Which procedures are associated with higher radiations doses?
» What are the possible effects of radiation on my health?
» How much radiation is acceptable?
» How do I know if the X ray facility is safe to perform the procedure?
» How will I know if I am getting the radiation dose that is needed and no more?
» Can I avoid unnecessary repeat investigations?
» Do I become radioactive after an X ray procedure?
» How does my doctor select the most appropriate investigation/procedure?
» What alternative investigations are available that do not use X rays or radioactivity?
» How do doses and risk from nuclear medicine compare to X rays?
» Can I undergo X ray investigations while I am pregnant?

» What are X rays and what do they do?

X rays are a form of electromagnetic radiation that can penetrate or pass through the human body and produce shadow-like images of bones and some organs. The images can reveal signs of disease and injury.
X rays are used in medicine in procedures such as:

• radiography, which produces a still X ray image;
• fluoroscopy, which  enables the observation of motion within the body and certain diagnostic and treatment procedures;
• computed tomography, which produces more detailed still images.

The body absorbs some of the X rays’ energy. The very low radiation doses absorbed during imaging procedures generally produce no adverse effects, but it is still recommended to reduce the doses as much possible. Very large radiation doses are used in radiation oncology or therapy to stop the multiplication of cancer cells.

» How safe are X rays?

Adverse effects from radiation dose absorbed in diagnostic practice are rare. For example, the radiation dose absorbed from a simple X ray examination such as a chest X ray (radiograph) or an X ray of the skull, abdomen, pelvic region, arms, shoulder or knees is quite low and is smaller than that received annually from natural sources.  Even at these low levels of radiation exposure, it cannot be excluded that the dose could cause cancer or genetic effects. There is no practical evidence of such effects from any human studies to date, but the theoretical possibility cannot be ruled out.

» Which procedures are associated with higher radiations doses?

Computed tomography (CT) and interventional procedures such as angiography and cardiac catheterisation are associated with higher doses of radiation, about 100 to 1000 times more than a chest X ray.

» What are the possible effects of radiation on my health?

Most diagnostic investigations will not have an adverse effect. Procedures with higher doses such as CT, interventional procedures or multiple exposures could lead to biological effects in some cases. A higher absorbed dose means a higher risk for adverse effects – the relationship is almost linear. Adverse effects could include skin redness, infertility, cataracts and hair loss. There are no reports of radiation exposure in diagnostic and interventional procedures causing infertility or cataracts. Patients undergoing interventional procedures that require fluoroscopy that lasts one hour or more could in very rare cases experience radiation induced skin injuries (erythema). Diagnostic X rays and nuclear medicine examinations lead to a slightly increased risk of cancer. This risk increases with the magnitude of the dose and with the number of procedures.

» How much radiation is acceptable?

There are no prescribed limits on radiation doses to patients. This means that no amount of radiation is considered too much for a patient when the procedure is justified by the doctor. The doctor will consider the benefits versus the risks. Several international organizations have established guidelines and recommendations based on scientific data. Every effort should be made to reduce the patient’s exposure to radiation. A principle known as ALARA – As Low as Reasonably Achievable – guides practices. An examination that serves no medical purpose is inappropriate, no matter how small the dose.

» How do I know if the X ray facility is safe to perform the procedure?

X ray equipment should be maintained by qualified staff and periodically tested. Radiation safety includes management of the doses patients are exposed to. Some organizations and agencies accredit facilities that fulfil safety related criteria.

» How will I know if I am getting the radiation dose that is needed and no more?

The following principles are helpful:

• Each examination should be justified. Benefits and risks of the intended examination or procedure should be considered, and the possibility of using other methods that do not involve radiation exposure should be explored. This is the principle of justification;
• Once justified, the examination should be performed with minimal radiation dose. This requires achieving adequate image quality while keeping the exposure as low as reasonably achievable. This is the principle of optimization and ALARA;
• The radiation dose could be compared with regional, national or international reference levels that indicate approximate dose levels for different medical procedures;
• Unnecessary repeat examinations should be avoided. Repeat examinations are sometimes needed to monitor progress, particularly with cancer treatment.

» Can I avoid unnecessary repeat investigations?

You can help avoid unnecessary repeat investigations by ensuring that your doctor has access to the results of earlier X rays. Even if this is not possible, it is essential to tell your doctor when the previous examination took place. Not all repeat investigations can be avoided – some are needed to determine a treatment’s effectiveness, for example.

» Do I become radioactive after an X ray procedure?

No.

X rays do not induce radioactivity.

Appropriateness and special situations

» How does my doctor select the most appropriate investigation/procedure?

Doctors are trained to determine the appropriate investigations for common medical conditions. They may use referral criteria such as those produced by the American College of Radiology, the European Society of Radiology and the Royal College of Radiologists. Doctors take medical histories, examinations, other test results and the radiation dose into account when they decide on an investigation method. Where possible, doctors choose alternative tests that do not expose patients to radiation.

» What alternative investigations are available that do not use X rays or radioactivity?

Ultrasound and magnetic resonance imaging (MRI) do not use X rays or radioactivity. Ultrasound is  useful for examining the pelvis and abdomen, particularly in pregnancy, and  for the breast, testes and soft tissues of the neck and limbs. Where available, MRI is increasingly used for scanning the head, spine and joints. 

» How do doses and risk from nuclear medicine compare to X rays?

Most diagnostic investigations in nuclear medicine expose the patient to a small dose of radiation similar to the range of doses received from X ray investigations.

» Can I undergo X ray investigations while I am pregnant?

Yes, but with certain precautions. 

The aim is to minimize  the unborn child’s radiation exposure. An unborn child is considered to be more sensitive than adults or children to potential adverse radiation effects. For many investigations such as X ray examinations of the head (including dental X rays), the chest and limbs, the dose to an unborn child would be very low as the patient’s pelvic region is not exposed to the X ray beam. 
All medically justified procedures can be conducted. 

Doctors may consider delaying  procedures that would put the pelvic region and the unborn child in the direct path of the X ray beam, particularly fluoroscopy or CT investigations. If the procedure is essential to the mother’s health, the doctors take special actions to keep the dose to the unborn child as low as possible. For example, pregnant patients can have their pelvic regions’ shielded during the procedure as an added precaution.

Scheme for the description of radiographs and fluoroscopy of the organs of the chest cavity. — 24Radiology.ru

1) Name and age of the patient.
2) General assessment of radiographs
Method.
– fluoroscopy
– radiography (survey, sighting radiograph).
– superexposed radiograph.
– tomogram.
— bronchogram.
– CT scan.
– angiogram.
Indication of the examined organs (thoracic organs).
Research projection (direct, lateral, oblique, lateroposition).
Image quality (contrast, sharpness, hardness of rays, correct stacking).
3) Study of the lungs.
Determining the shape of the chest (normal, bell-shaped, barrel-shaped).
Assessment of lung volume (not changed, lung or part of it is enlarged, reduced).
Establishment of the state of the lung fields (transparent, darkening, enlightenment).
Analysis of the lung pattern (not changed, strengthened, weakened, deformed).
Analysis of the roots of the lungs (structurality, width, location, enlarged lymph nodes, vessel diameter).
Functional state during fluoroscopy (respiratory movements of the ribs, diaphragm, changes in the lung pattern during breathing)

Identification and description of pathological syndromes.
1) Shadow picture
Darkening.
Enlightenment.
2) Localization
By shares
By segments.
3) Dimensions in centimeters (at least two dimensions are indicated).
4) Shape
Round.
Oval.
Invalid.
Triangular.
5) Contours
Smooth or uneven
Clear or indistinct
6) Intensity
Weak
Medium
High
Lime density
Metallic density
7) Shadow structure.
Homogeneous
Heterogeneous
8) Functional signs on fluoroscopy
9) Change in the shape of a round shadow during breathing – with liquid formations (cysts).
10) Shadow pulsation in vascular formations (aneurysms, angiomas), etc.
11) Correlation of pathological changes with surrounding tissues:
Enhancement of lung pattern in surrounding tissues
Enlightenment rim around a round shadow by pushing adjacent tissues
Pushing or pulling apart bronchi or vessels, etc.
Dropout centers.

4) Study of the mediastinal organs
1) Location
Not displaced
Displaced (towards pathological changes in the lungs or in the opposite direction).
2) Dimensions:
Not enlarged
Dilated due to the left ventricle or other parts of the heart;
Widened to the right or left in the upper, middle or lower sections.
3) Configuration
Not changed
If changed, it may be due to volumetric formations of the heart, blood vessels, lymph nodes, etc.
4) Contours.
Smooth
Irregular
5) Functional state during fluoroscopy
Heart rate
Jerky displacement of the mediastinum during expiration towards atelectasis, etc.

5) Examination of the walls of the chest cavity.
1) Condition of the sinuses of the pleura
Free
Contains fluid
Has pleurodiaphragmatic adhesions.
2) Condition of soft tissues
Not changed
Enlarged
There is subcutaneous emphysema
Foreign bodies, etc.
3) Condition of the skeleton of the chest and shoulder girdle collapsed fractures.
4) Diaphragm condition
Ordinary location
Proximal displacement by one intercostal space, etc.
Domes have smooth contours or are deformed by pleurodiaphragmatic adhesions.
Diaphragm mobility under fluoroscopy.

CONCLUSION
RECOMMENDATIONS on the use of additional methods.
DESCRIPTION of additional techniques and methods confirmation or clarification of the previously described picture, description of newly identified pathological signs.
FINAL REPORT (e.g. pneumothorax, parenchymal pneumonia, central exobronchial carcinoma without metastases, peripheral carcinoma, echinococcus in non-opened phase, etc.)

Chest X-ray – Systems Approach

Introduction

A systematic approach to the analysis of chest x-rays is used to ensure that important structures are not missed, and a flexible approach is needed for different clinical situations.

Although there is no single agreed upon order of image analysis, you can find many examples of chest x-ray descriptions.

Below is a short example.

Anatomical structures checklist

1. Trachea and major bronchi

2. Lung roots

3. Lung fields

4. Pleura

5. Lung lobes/interlobar fissures

6. Costophrenic sinuses

7. Diaphragm ragma

8. Heart

9. Mediastinum

10. Soft Tissue

11. Skeletal Framework

This guide will help you develop your own analysis system, from patient data, image data, and image quality. Next, you will study where and what pathological changes can be described. The manual also discusses an overview of blind spots where it is easy to miss a pathological process. Your results will be better if you are able to analyze and relate clinical data to radiological findings.

Patient and image data

Patient identifiers and date

Patient identification must be performed before X-ray image interpretation. The date of the examination, as well as, necessarily, the time, must be noted, as the patient may have more than one radiograph on the same day.

Image Projection

Note which view, AP or AP, the image was taken; standing, lying or sitting; stationary or mobile device.

Image annotations

Useful information is often displayed on an image. If the projection is not marked, it is likely that the image was taken in a standard anterior-posterior (PA) projection. If there are side markers, pay attention to the correct position of their position.

Image quality

Image quality should always be assessed because clinical questions cannot be answered if the image quality is inadequate.

Pay attention to the rotation of the chest, the depth of inspiration and the adequacy of the penetrating power of the X-ray radiation.

Image annotations

Artifacts

When you describe a chest x-ray, it is good practice to comment on the presence of any artifact.
An example is shown below.

Central catheter position ?

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A large number of radiographs are taken to evaluate the position of medical equipment such as a nasogastric tube or central catheter. If you are evaluating a chest x-ray for this purpose, remember to evaluate the entire image systemically.

Obvious pathology

It is advisable to start the analysis with the most pronounced pathology. However, once done, it is important to continue analyzing the rest of the image according to the checklist. Remember that a more prominent pathology may not be of clinical significance.

For example, don’t make the mistake of devoting most of your time to rigorously following a systems approach while ignoring obvious pathology.

The rule can be summarized as – don’t ignore the “elephant” in the picture – describe its long trunk, its large ears, tusks and rough, gray skin and you will be more likely to diagnose the “animal” you are dealing with, but then you must continue analysis using a systematic approach to watch the rest of the image.

Description of the pathology

The art of radiology, not merely in stating and describing pathological features, but knowing how to relate the meaning of these pathological features and knowing which ones can be omitted. First, describing radiographic features can be difficult and many medical students want clear terminological rules. However, in reality there are no clear rules. The main difficulties begin when describing the pathology of the lung parenchyma. What one radiologist describes as “darkening” may be referred to by others as “decrease in pneumatization” or “infiltration.” In fact, all of these terms are acceptable.

The description of the pathology on a chest x-ray can be compared with the description of a skin rash in a dermatological patient. Attention should be directed to such features as quantity, localization, size, shape, density and structure.

Special Findings

There are many specific X-ray findings that can guide you to the correct diagnosis. For example, occlusion of the costophrenic sinus, forming obtuse angles with the chest wall, should make you think of a pleural effusion. Obvious consolidations (infiltrations) with a sign of an air bronchogram should first of all suggest an infectious process. These signs must be indicated in the descriptive picture.

If you see one of these clear signs, try not to jump to conclusions. Continue the systematic description of the changes and perhaps you will see that the blunting of the angle of the costophrenic sinus is caused by emphysematous enlargement of the lung fields, and the consolidation of the lung tissue is combined with the destruction of the rib, making cancer a more likely diagnosis? than pneumonia.

Location of changes

In addition to determining the side of the identified changes, it is necessary to evaluate the localization in the anterior-posterior projection. A lateral view helps to localize changes in 3D space, but it is also possible from a direct view, with knowledge of x-ray anatomy and understanding of shadow contours.

Contour sign

Contour sign is an erroneous name, it is more correct to call it a “lost contour” sign. Normal adjacent anatomical structures of varying density form clear “silhouettes” or contours. Violation of normal boundaries can help determine the position of the pathological process.

For example, the heart (soft tissue density, white) borders on the lung tissue (air density, dark color). A clear contour, or “silhouette” is formed at the junction of two fabrics of different density. The loss of a clear contour of the right heart (formed by the right atrium) suggests localization of the disease in the right middle lobe, which is adjacent to the right atrium. The loss of the density difference of the left heart contour indicates the pathology of the lingular regions (the part of the upper lobe of the left lung that surrounds the left ventricle).

Changes simulating contour sign

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Changes simulating contour sign

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05

After a systematic complete inspection chest, it is worth re-checking areas that may hide an important pathology.

It is always worth double-checking that there is no pneumothorax or pneumoperitoneum. And indicating their absence in the descriptive part is a good practice.

Pneumothorax is easily seen at the apex on an anterior-posterior radiograph. Pneumoperitoneum (free gas under the diaphragm), only visible on x-ray taken while standing

Other areas to look at include soft tissue, bone, posterior mediastinum, and image margins.

Inspection areas – Apexes

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Inspection areas – Bones

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Area Inspection – Heart Shadow

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Area Inspection – Aperture

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Area Inspection – Edges of Image

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Clinical Tasks 901 05

At first, most students think that radiography gives accurate answers without comparison with clinical data. Sometimes this may be the case, but ideally radiography should always be interpreted in full correlation with the clinical findings. Most radiological conclusions can only be given in the light of clinical data. Thus, you should always be provided with specific clinical data when requesting an x-ray.

Often the results will confirm the preliminary diagnosis, and the absence of changes will improve the prognosis, since an experienced clinician will often know the diagnosis before the X-ray examination, and use it to clarify the extent and localization of the pathological process.

Therefore, results should only be interpreted in relation to clinical data. Remember, the radiologist does not treat the patient. Occasionally there will be incidental findings that require careful consideration, especially if they can be interpreted in two ways or if they do not correspond to clinical data.

No clinical data provided

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Clinical data provided

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missing important changes.

Patient data and image quality must always be evaluated.