Dr. Ertan Beyatlı

What are ADBG and PAAC Graphs?

(Update: ) - general subjects


ADBG - Standing Direct Abdominal X-ray (Flat Abdominal X-ray) is an abdominal X-ray taken standing upright. Shown in emergency situations. For example: kidney pain (Renal Colic), Intestinal Obstruction (Ileus, Sub-ileus, Volvulus), Bowel and Stomach Perforation (perforation), Appendicitis, intussusception, Foreign Body ingestion or rectal insertion. In Latin standing direct abdominal radiograph written as.

Standing Direct Lose Film

Post-exposure, interpretation of the ADBG is very important. In particular, it is drawn to detect the air-fluid level due to trauma, to observe intestinal obstructions, gases and abnormal structures in the soft tissue.

Gastric Puncture (Gastric Perfpration): Right sub-diaphragmatic free air seen in ADBG - inverted crescent finding
Gastric Perforation (Gastric Perfpration): Right sub-diaphragmatic free air seen in ADBG - inverted crescent finding

Free air seen under the diaphragm (subdiaphragmatic inverted crescent sign) is more clearly seen on the PA Chest X-ray.

How to shoot ADBG?

It is inconvenient and unbearable in pregnant women. The patient is given a disposable gown and asked to take off his clothes and necklace, if any, and put on the given apron.

Shooting should be done in a standing position and in the PA (Back-Front) position. The patient's abdomen should touch the stand. A cassette (35X43) or detector should be chosen in a way that will not cut the diaphragm domes. Tube cassette distance should be 100 cm. Centralization should be done 5 cm above the iliac crest, perpendicular to the film. After the patient's position is adjusted and the necessary dimensions are collimated, the patient is told to take a deep breath (inspiratory). For an average adult, shooting can be done with 100 KV and automatic MaS.

ADBG principles
ADBG principles

Things to pay attention

Most of the patients forget to remove underwear, jewelry etc. When the patient is prepared for shooting, it should be checked again. Especially in breathtaking shots, many patients cannot fulfill the breath command given, in order to avoid this and to obtain the optimum view, the patient should be observed and controlled to breathe when the breath command is given. To summarize

  • Question your pregnancy credentials and complaints
  • Distance 100 cm
  • KV: 110 MaS automatic
  • Deep inspiration


PA chest radiography is the most common film for the chest area. PA stands for posteroanterior posterior-anterior. The abbreviation is PA ACG. English PACXR (PA Chest X-ray)

The patient is standing, leaning his chest against the tape, and the X-ray film is taken from the back from a distance of 180 cm. Since the heart and main vessels are far from the cassette, it appears larger than normal. PA chest radiography when the patient is fully breathing (inspiration) is drawn. The amount of X-ray beam delivered determines the darkness of the film. In addition, directions are determined on the films. (R-Right-right, L-Left-Left)

Interpretation of PA Chest X-ray (PA ACG)

Through this film, the trachea, chest and heart rate (cardiothoracic ratio), jugular vein (aorta), lung, thoracic cavity (mediastinum) and diaphragm are evaluated. Free air under the diaphragm (sub-diaphragmatic) Standing Direct Abdominal Graph (ADBG) it is seen more clearly. For example Bağısak and stomach perforation, appendicitis burst situations.

Chest X-ray - PA ACG
Chest X-ray - PA ACG

When is PA Chest X-ray taken?

PA ACG is frequently used in the diagnosis and follow-up of acute and chronic diseases. It is withdrawn for health check prior to employment. It can be taken for routine pre-operative screening. It can be withdrawn in situations such as cough, fever or pain. Also PA ACG pneumonia (pneumonia) is an excellent initial imaging test to evaluate for pulmonary edema, COPD or pleural effusion.

PA Chest X-ray Markings

Silhouette sign

Named by Felson, this sign defines that a parenchymal opacity will cause the boundary between the anatomically related soft tissue to be erased. The most commonly used soft tissue is the heart and its adjacent right middle lobe and the parenchyma of the lingula. Lesion localization can be done, since the boundary between these areas will be erased in the loss of ventilation in these areas and the pathologies of different areas will not be erased due to the same reasons.

"Hilum overlay" sign

It is the form of silhouette sign adapted to hilus. In cases where the hilar vessels can be distinguished from the lesion, it is understood that the lesion is anterior or posterior to the hilus. Deletion of the vessels due to the lesion indicates that the lesion localization is hilus. Air bronchogram The name given to the appearance of air-filled bronchi with air-free lung parenchyma. This appearance indicates that the proximal airways are open and the air in the alveoli is either resorbed or replaced. Resorption is the cause of atelectasis, the most common reason for replacement is pneumonia or is pulmonary edema.

Crescent sign

This finding, also known as the meniscus sign, is the accumulation of crescent-shaped air between the wall of a parenchymal cavity and the mass inside. Typically seen in Aspergillus colonization within cavities. Another form of occurrence is retraction of necrotic parenchyma during the recovery period of angioinvasive aspergilllosis cases.

Golden S sign

This finding, defined by Golden, is seen in right upper lobe atelectasis accompanying a central mass. While the medial part of the minor fissure is inferiorly convex, the lateral part is observed as concave inferiorly. These changes cause the fissure to be seen as an inverted S on PA radiography. Cervicothoracic sign is helpful in determining the localization of a lesion in the thoracic entrance in the mediastinum. Since the lung apex parenchyma has a more superior extension in the posterior, a lesion located in the posterior mediastinum extends over the clavicle on PA radiography and its borders are clearly defined. Lesions located in the anterior mediastinum are observed under the clavicle and cannot be distinguished from cervical soft tissues.

Luftsichel sign

This sign, which is a combination of the German words air and sickle, is seen in the left upper lobe collapse. As a result of the superior segment of the lower lobe entering between the aortic arch and the atelectatic left upper lobe, a hyperlucent sickle-shaped appearance occurs.

Machete sign

It is the view of the curved tubular structure of the abnormal pulmonary vein extending to the diaphragm along the right contour of the heart. Abnormal right inferior pulmonary vein usually drains into the inferior vena cava adjacent to the hemidiaphragm.

Hampton hump sign

It is an opacity that develops secondary to pulmonary infarction and sits on the pleura with its wide base. The apex of the lesion is convex, as the lung parenchyma also feeds from the bronchial arteries. The cause of opacification is alveolar hemorrhage secondary to pulmonary infarction. It usually occurs in the lower lobes and improves with linear scar formation.

Westermark Find

It indicates decreased peripheral vascularization caused by oligemia due to vasoconstriction in pulmonary embolism. PA is viewed as a radiolucent area on radiographs. Although its sensitivity is low, it has high specificity like Hampton's hump sign.

Juxtaphrenic crest

In upper lobe atelectasis or lobectomy, it is the name given to the triangular shaped opacity with an upper apex in the middle part of the diaphragm on the same side. It is thought that atelectasis occurs as a result of the superior retraction of the visceral pleura due to negative pressure and inferior accessory fissure in these patients due to the protrusion of extrapleural adipose tissue. It is more common in the right lung than in the left, and it can also be observed in right middle lobe atelectasis.

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