LUNG LOBE TORSIONS

LUNG LOBE TORSIONS

Acc# 146824

LUNG LOBE TORSION

• Definition: Rotation of a lung lobe around its long axis

• Signalment:– Increased incidence in large deep chested, middle

aged dogs(Afghan hounds)– Also seen in small breed dogs(Pugs)

• Clinical Signs:– Resp distress, coughing, hemoptysis, depression,

lethargy, fever, anorexia

PATHOPHYSIOLOGY

• Lung lobe rotates around its axis twisting the bronchus and vessels at the hilus– Vein collapses first, artery continues to pump

blood• Leads to congestion and consolidation• Fluid leaks into the interstitium and airways and

eventually into the pleural space– Most commonly affected lobes are the right

middle in large breed dogs(Afghans) and left cranial in small breeds(Pugs)

CAUSES

• Unknown most of the time• Often associated with thoracic trauma,

surgery, pleural effusion, pneumothorax and neoplasia

• Spontaneous also occurs

CAUSES

• Thought to be due to conditions that result in increased mobility of a lung lobe– Atelectasis or consolidation

• Pleural effusion commonly seen with LLT– Cause or sequelae not known– Effusion may be sterile, inflammatory, chylous , or

hemorrhagic

RADIOGRAPHIC SIGNS

• Pleural effusion and opaque/mass effect of the lung lobe

• Initially air bronchograms may be seen extending in an abnormal location– Become less visible as fluid accumulates in the airways

• Eventually the air is absorbed from the alveoli and the lobe becomes atelectic

• Non-inflated lung that persists post thoracocentesis• Rounded lobe margins as lung becomes engorged• Lobar sign

ACC# 146824

• 11 yr old FS Pug• Presented to NCSU ER – 1 week hx of lethargy and inc RR– rDVM suspicious of lung lobe torsion for

pneumonia vs neoplasia– Gave 1 day of Clavamox

THORAX DV

THORAX RIGHT LATERAL

THORAX VD

AFGHAN

DIFFERNTIALS

• Radiographic appearance depending on severity and duration of torsion may also look like:– Pneumonia, PTE, contusions, neoplasia,

atelectasis, pleural hemorrhage, pyothorax, and diaphgragmatic hernia

ADDITIONAL IMAGING

• Computed Tomography

• Ultrasound

• Bronchoscopy

• Exploratory Surgery

ULTRASOUND 2 YR FS PUG

http://article.wn.com/view/2000/12/04/Atelectasis_Airlessness_causes_partial_lung_contraction/

TREATMENT

• Supportive Oxygen• Thoracocentesis• Lung lobectomy is usually curative depending

if there is an underlying cause• Histopathology of resected lobe recommended