Deep sulcus sign

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Deep sulcus sign
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Specialty	Radiology
Symptoms
Complications
Onset
Duration
Types
Causes	Pneumothorax
Risks
Diagnosis	Chest X-ray
Differential diagnosis
Prevention
Treatment
Medication
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Frequency
Deaths

The deep sulcus sign is a radiological sign seen on a supine chest X-ray that suggests the presence of a pneumothorax. It is characterized by an abnormally deep and lucent costophrenic angle on the affected side, due to the accumulation of air in the pleural space. This sign is particularly useful in detecting a pneumothorax in patients who are unable to sit upright for a standard chest X-ray. Radiological sign of pneumothorax

The deep sulcus sign is a radiological finding that is indicative of a pneumothorax, particularly when the patient is in the supine position during a chest X-ray. This sign is characterized by an abnormally deep and lucent costophrenic angle on the affected side, which is caused by the accumulation of air in the pleural space.

Pathophysiology

A pneumothorax occurs when air enters the pleural space, the area between the visceral pleura and the parietal pleura. This can lead to a partial or complete collapse of the lung. In a supine patient, the air tends to collect anteriorly and basally, which can make the detection of a pneumothorax challenging on a standard anteroposterior chest X-ray. The deep sulcus sign is a useful indicator in such cases.

Radiological Appearance

On a supine chest X-ray, the deep sulcus sign manifests as an unusually deep and radiolucent costophrenic angle on the side of the pneumothorax. This is due to the air collecting in the most anterior and inferior part of the pleural cavity, which is the costophrenic angle when the patient is lying down. The sign is more pronounced on the affected side and can be subtle, requiring careful examination of the X-ray.

Clinical Significance

The deep sulcus sign is particularly important in the diagnosis of pneumothorax in patients who are unable to sit upright for a chest X-ray, such as those who are critically ill or immobilized. Recognizing this sign can prompt further investigation or intervention, such as a CT scan or the insertion of a chest tube to evacuate the air and re-expand the lung.

Differential Diagnosis

While the deep sulcus sign is a strong indicator of a pneumothorax, it is important to consider other potential causes of an abnormal costophrenic angle on a chest X-ray. These can include:

• Pleural effusion
• Hemothorax
• Diaphragmatic hernia

See also

• Pneumothorax
• Chest X-ray
• Pleural cavity
• Radiology