Radiographic Diagnosis of Laryngeal Paralysis in Nonsedated Dogs

Source

Touzet C, Hahn H, Gomes E, Bismuth C, Le Boedec K. Assessment of survey radiography as a method of diagnosing bilateral laryngeal paralysis in dogs. Vet Radiol Ultrasound. 2022. doi:10.1111/vru.13192

Research Note

Laryngoscopy with the patient under light anesthesia is the gold standard for diagnosis of laryngeal paralysis in dogs.  

This study examined the diagnostic accuracy of 2 radiographic laryngeal ventricle measurements, as well as shape evaluation, for noninvasive screening in nonsedated dogs. Eighteen dogs with bilateral laryngeal paralysis and 25 healthy dogs were placed in right lateral recumbency with the head in physiologic position, including the nose being slightly elevated from the table. Framing was centered on the larynx and included the tympanic bullae, temporomandibular joints, and body of the third cervical vertebra (C3).  

Maximal ventricular length to body length of C3 (MVL/LC3) was the most accurate radiographic index, with bilateral laryngeal paralysis considered very unlikely if the value was <0.3 and very likely if the value was >0.5. Further diagnostics are needed if MVL/C3 is between these 2 threshold values or if otherwise clinically indicated.