Computed tomographic features of lung lobe torsion

Area of Science:

• Veterinary Radiology
• Comparative Pathology
• Canine Thoracic Imaging

Background:

• Lung lobe torsion is a rare but serious condition in dogs.
• Accurate diagnosis is crucial for effective treatment and prognosis.
• Computed tomography (CT) offers detailed anatomical visualization.

Purpose of the Study:

• To describe the computed tomography (CT) imaging features of lung lobe torsion in dogs.
• To compare contrast enhancement patterns between normal, torsed, and adjacent lung lobes.
• To identify key CT findings indicative of lung lobe torsion.

Main Methods:

• Retrospective review of helical single-slice CT scans from 10 dogs with lung lobe torsion.
• Analysis of attenuation values in normal, torsed, and collapsed lung lobes before and after contrast administration.
• Correlation of CT findings with clinical and surgical data.

Main Results:

• Complete lung lobe torsion (9/10 dogs) showed pleural effusion and abruptly ending bronchi.
• Enlargement, consolidation, emphysema, and mediastinal shift were observed in 8/9 dogs with complete torsion.
• Torsed lung lobes exhibited no contrast enhancement, unlike adjacent collapsed or aerated lobes (P < 0.05).
• Affected lobes included left cranial (5), right middle (3), right cranial (1), and left caudal (1).

Conclusions:

• CT is a valuable tool for diagnosing canine lung lobe torsion.
• Lack of contrast enhancement in the affected lobe is a key diagnostic indicator.
• Induced apnea is essential for reducing motion artifacts and ensuring diagnostic quality CT scans.