Clinical History
A 31-year-old man was brought to the emergency department of our hospital after being found lying unconscious in a crop field. It was reported that he had been thrown into it out after falling out from a car accident. He was in a grave condition.
Imaging Findings
Chest radiograph showed a large focal density at the left upper lung zone, and atelectasis of the left lower lobe with significant blunting of the left costophrenic angle consistent with pleural effusion (Fig. 1). Computed tomography (CT) images disclosed a large loculated effusion at the anterior segment of left upper lobe with a small air-fluid-level at the non-dependant part of it raising concern for empyema or abscess formation (Fig. 2-4). None of these images revealed the presence of a foreign body within the loculated effusion. Ultrasonography (US) performed at the lesion site showed an echogenic focus within the effusion, demonstrating acoustic shadowing posteriorly (Fig. 5). The patient underwent an operation, which revealed the presence of a wooden foreign object within the lesion (Fig. 6). The object was extracted successfully (Fig. 7), and the patient did well afterwards, being discharged from the hospital in a rather short period of time.
Discussion
Thoracic trauma is a common cause of significant disability and mortality, being the leading cause of death from physical trauma after head and spinal cord injury (1, 2). Blunt thoracic injuries are the primary cause of about a quarter of all trauma-related deaths with a mortality rate of about 10% (2). Chest trauma is classified as blunt or penetrating. On the other hand, most penetrating injuries are chest wounds and have a mortality rate around 10%. Penetrating chest trauma can injure vital organs such as the lung and heart.
Impalement injuries are relatively uncommon during vehicular trauma (3). Penetration of the chest with a wooden object, particularly during a traffic accident, is a rarer event. But there are case reports in the literature, concerning wooden object impalement in the chest (3, 4, 5, 6). Because wood, as a substance, is not easily visualised by means of X-ray examination, the diagnosis of a foreign wooden object in the chest may sometimes be difficult, as was in our case.
When the presented patient was brought to the emergency department, he was in a grave clinical condition. His posteroanterior chest radiograph and CT revealed a mass-like opacity and a loculated pleural effusion accordingly in the left upper lung region containing an air-fluid level, indicative of an empyema or abscess-like inflammatory process. In none of these examinations could a proper diagnosis of a foreign object embedment be made. It was only when an US examination was performed, that a foreign object with an acoustic shadow could be demonstrated. US played a major role in the diagnosis process. The patient underwent an operation which verified the presence of a wooden foreign object within the lesion.
We conclude that a multimodality radiological approach is fundamental in the evaluation of a trauma patient, especially in the presence of clues pointing to the possibility of a traumatic foreign object implantation.
Differential Diagnosis List
Penetrating lung injury from a wooden foreign object
Haematoma due to chest trauma
Coincidental pleural mass
Final Diagnosis
Penetrating lung injury from a wooden foreign object
