CASE 11690 Published on 14.04.2014

Traumatic pulmonary torsion leading to complete bronchovascular avulsion

Section

Cardiovascular

Case Type

Clinical Cases

Authors

Amir Awwad, Yutaro Higashi, Greg Ramjas

Nottingham Univ. Hospitals,
Radiology Department;
Derby Road NG7 Nottingham;
Email:amirawwad@hotmail.com
Patient

45 years, female

Categories
Area of Interest Arteries / Aorta, Cardiovascular system, Lung, Emergency ; Imaging Technique CT
Clinical History
Following a fall from the 5th floor, an emergency admission of a severely shocked patient (GCS 3/15) led to a clam shell thoracotomy and urgent laparotomy on arrival at the hospital. Intra-operatively, no clear source of acute haemorrhage was identified. Subsequently, a poly-trauma tri-phasic CT was performed.
Imaging Findings
The right main pulmonary artery can be seen to terminally “beak” on the axial images with a cut-off sign of the main right bronchus at the same level. There is a shallow right-sided pneumothorax managed by the insertion of an indwelling intercostal chest drain. Marked oligaemia and parenchymal contusional change of the distal lung are evident. On sagittal reformatted images, a noticeable swirled configuration of the right hilum confirms the presence of a traumatic pulmonary torsion.
Discussion
Pulmonary torsion is a rare but potentially rapidly fatal condition that involves a 180 degree or greater hilar twist of the lung resulting in devascularisation and complete collapse [1].

In literature, the most common cause is secondary to surgery with most case reports following either lung transplantation or more frequently lobectomy [2, 3, 4]. In theory, the increased intrathoracic potential space created following surgery can redistribute the pulmonary fissures in an abnormal way sufficient to facilitate the twisting of the remaining lobe(s) and thus compromising the vascular and bronchial pedicle [5].

The diagnosis should be suspected on radiographs with an unusually located collapsed lobe and features suggestive of venous congestion. Computer Tomography with multi-planar reformatting can better delineate the anatomy and the degree of torsion as well as assess the vascularity of the affected lung. Other cases are seen in patients with underlying congenital thoracic abnormalities and in rare cases such as sequestration [7].

Pulmonary torsion causes a combination of arterial and bronchial inflow whilst also causing venous and cardiac outflow obstruction and hence pulmonary congestion, infarction and potential intrathoracic tension [6].

This case illustrates how traumatic case of pulmonary torsion that has acutely presented with severe thoracic trauma and tension pneumothorax resulted from the disruption of the pulmonary ligaments and subsequent hilar twist.

The diagnosis can be made using an arterial phase MDCT with multi-planar reconstruction. The beaked appearance of the abrupt termination of the pulmonary artery on the axial images and swirled appearance on sagittal imaging are indicative of the torsion.

This necessitates emergency surgical correction and anastomosis, otherwise mortality is very high [4, 5]. MDCT (arterial phase) is an excellent way of demonstrating the displaced anatomy and reduced vascularity of the affected lung although the viability of the lung itself can only be accurately assessed at the time of surgery.
Differential Diagnosis List
Acute pulmonary torsion with bronchovascular avulsion.
Traumatic pulmonary contusion
Acute pulmonary embolism
Final Diagnosis
Acute pulmonary torsion with bronchovascular avulsion.
Case information
URL: https://www.eurorad.org/case/11690
DOI: 10.1594/EURORAD/CASE.11690
ISSN: 1563-4086