Lung torsion is the rotation of a lung or lung lobe about its bronchovascular pedicle and resulting in ischemia. It is very rare, and typically occurs in the setting of lobectomy or pneumonectomy. It has also been reported as a rare complication of less invasive procedures such as video-assisted thoracic surgery (VATS) 11, following large-volume thoracentesis 15, or even spontaneously in the native lung.
It has a reported incidence of 0.09-0.4% 12.
Torsion result from rotation of a lobe (or entire lung) around hilar structures. The degree of rotation is variable, ranging from 90° to 360° (most commonly 180°).
The torted lung creates a trifold compromise of the airways, arterial blood supply and the venous-lymphatic drainage 13 due to luminal kinking. The affected lobe often shows hemorrhagic infarction or necrosis.
Described predisposing factors include 7 :
- presence of a pneumothorax and or pleural effusion
- existence of a free and long vascular pedicle to the lung
- existence of a non-ventilated lobe
On plain film, it can be suspected when a collapsed or consolidated lobe is seen in a an unusual position especially in the context of a recent pneumonectomy 4. The affected lobe is often opacified 5. Rapid opacification of the lung following trauma/surgery or marked change in position of opacified lobe on short interval serial radiographs or an unusual position of a collapsed lobe can aid to the diagnosis. Other radiographic findings include inappropriate hilar displacement and a reticular pattern from venous congestion.
Findings are often non-specific and the involved lung may simply appear atelectatic. A high index of suspicion, particularly in the post-surgical setting, is required. CT angiography, especially with maximum intensity projection (MIP) reconstruction, is particularly useful in demonstrating a twisted pulmonary artery morphology 16.
- bronchovascular findings
- tapered obliteration of the proximal pulmonary artery and accompanying bronchus (may appear similar to mucus plugging 16)
- antler sign - abnormal curved orientation of the main pulmonary artery with branch vessels appearing to originate from a single side (versus normally-distributed arborisation) 16
- amorphous soft-tissue attenuation at the hilum
- pulmonary parenchymal findings
- abnormal appearance of the fissure
- post-lobectomy neofissure can appear to bulge, with unusual orientation
- change or unexpected position of lobectomy surgical staples may also provide evidence for abnormal rotation 17
Treatment and prognosis
Lung torsion is considered a medical emergency. The optimal therapeutic approach remains controversial 14. The decision for detorsion or lobectomy usually depends on the viability of the torted lung which is better appreciated after open thoracotomy. Detorsion offers lung salvage but if inappropriate, it may lead to thoracotomy and lobectomy.
Other early or late post lobectomy complications (pneumonia, vascular occlusion) with similar clinical presentation.
- 1. Gilkeson RC, Lange P, Kirby TJ. Lung torsion after lung transplantation: evaluation with helical CT. AJR Am J Roentgenol. 2000;174 (5): 1341-3. doi:10.2214/ajr.174.5.1741341 - Pubmed citation
- 2. Kim EA, Lee KS, Shim YM et-al. Radiographic and CT findings in complications following pulmonary resection. Radiographics. 2002;22 (1): 67-86. Radiographics (full text) - Pubmed citation
- 3. Munk PL, Vellet AD, Zwirewich C. Torsion of the upper lobe of the lung after surgery: findings on pulmonary angiography. AJR Am J Roentgenol. 1991;157 (3): 471-2. doi:10.2214/ajr.157.3.1872230 - Pubmed citation
- 4. Felson B. Lung torsion: radiographic findings in nine cases. Radiology. 1987;162 (3): 631-8. Radiology (abstract) - Pubmed citation
- 5. Moser ES, Proto AV. Lung torsion: case report and literature review. Radiology. 1987;162 (3): 639-43. Radiology (abstract) - Pubmed citation
- 6. Kucich VA, Villarreal JR, Schwartz DB. Left upper lobe torsion following lower lobe resection. Early recognition of a rare complication. Chest. 01;95 (5): 1146-7. doi:10.1378/chest.95.5.1146 - Pubmed citation
- 7. Demir A, Akin H, Olcmen A et-al. Lobar torsion after pulmonary resection; report of two cases. Ann Thorac Cardiovasc Surg. 2006;12 (1): 63-5. Pubmed citation
- 8. Kanemitsu S, Tanaka K, Suzuki H et-al. Pulmonary torsion following right upper lobectomy. Ann Thorac Cardiovasc Surg. 2007;12 (6): 417-9. Pubmed citation
- 9. Chung SH, Nam JE, Choe KO et-al. Radiologic findings of lung lobe torsion in reconstructed multidetector computed tomography image lead to early detection. Clin Imaging. 2010;34 (5): 400-3. doi:10.1016/j.clinimag.2009.10.035 - Pubmed citation
- 10. Spizarny DL, Shetty PC, Lewis JW. Lung torsion: preoperative diagnosis with angiography and computed tomography. J Thorac Imaging. 1998;13 (1): 42-4. Pubmed citation
- 11. Duan L, Chen X, Jiang G. Lobar torsion after video-assisted thoracoscopic lobectomy: 2 case reports. Thorac Cardiovasc Surg. 2012;60 (02): 167-9. doi:10.1055/s-0030-1271182 - Pubmed citation
- 12. Niekel MC, Horsch AD, Ven Mv et-al. Right middle lobe torsion: evaluation with CT angiography. Emerg Radiol. 2009;16 (5): 387-9. Emerg Radiol (full text) - doi:10.1007/s10140-008-0774-6 - Pubmed citation
- 13. Nguyen JC, Maloney J, Kanne JP. Bilateral whole-lung torsion after bilateral lung transplantation. J Thorac Imaging. 2011;26 (1): W17-9. doi:10.1097/RTI.0b013e3181e35ab5 - Pubmed citation
- 14. Souilamas R, Couchon S, Hernigou A et-al. Management of lobar torsion following lung transplantation. Asian Cardiovasc Thorac Ann. 2009;17 (2): 196-8. doi:10.1177/0218492309103322 - Pubmed citation
- 15. Irie M, Okumura N, Nakano J, Fujiwara A, Noguchi M, Kayawake H, Yamashina A, Matsuoka T, Kameyama K. Spontaneous whole-lung torsion after massive pleural effusion and atelectasis. (2014) The Annals of thoracic surgery. 97 (1): 329-32. doi:10.1016/j.athoracsur.2013.04.133 - Pubmed
- 16. Hammer MM, Madan R. Clinical and imaging features in lung torsion and description of a novel imaging sign. (2018) Emergency radiology. 25 (2): 121-127. doi:10.1007/s10140-017-1563-x - Pubmed
- 17. Yanagihara T, Ichimura H, Kobayashi K, Sato Y. Computed tomography detection of stapled interlobar fissure facilitates diagnosing postoperative lobar torsion: A case report. (2017) International journal of surgery case reports. 41: 86-88. doi:10.1016/j.ijscr.2017.10.013 - Pubmed