Research explores pterygoid bone links to BOAS surgery
French bulldogs with more severe cases of pterygoid bone medialisation are more likely to have poor BOAS surgery outcomes.
A new study has linked the medialisation of pterygoid bones to poorer surgical outcomes from brachycephalic obstructive airway syndrome (BOAS) surgery.
Researchers have suggested that measuring the severity of the medialisation could provide an indicator for the prognosis of such surgery, especially in French bulldogs.
The project saw researchers from the University of Cambridge analyse CT images depicting the head and neck of 144 brachycephalic dogs, including French bulldogs, pugs and English bulldogs. This was compared to images from 30 non-brachycephalic dogs.
The dogs' BOAS index was assessed before and after the surgery.
Analysis identified that the medialisation of pterygoid bones was more severe in brachycephalic breeds than non-brachycephalic breeds. The medialisation was found to be closely associated with nasopharyngeal narrowing, with severe cases more likely to limit the effectiveness of BOAS surgery.
French bulldogs with more severe cases of pterygoid bone medialisation were most likely to have poor outcomes from BOAS surgery.
Although there are no effective interventions to correct pterygoid bone deformities, researchers suggest that the severity of the medialisation should inform surgery prognoses. They recommend that evaluating pterygoid malformations should form part of clinical assessments to inform surgery prognosis.
The medialisation of pterygoid bones can be identified through CT imaging. A simple palpation of the pterygoid bone during surgery of an oral cavity can also indicate medialisation levels.
The study is the first to investigate how pterygoid bone medialisation and nasopharyngeal narrowing impact BOAS surgery for both brachycephalic and non-brachycephalic dogs.
Dr Sze Lynn Yuen, lead author of the study, said: “BOAS is a complex disease which encompasses breed-specific anatomical lesions.
“The medialisation index will be useful for vets in practice to guide them on the likely prognosis prior to surgery. It would be beneficial to identify the significance of the medialisation index on a larger dataset of BOAS-affected patients as the next step.”
The full study has been published in the Journal of Small Animal Practice.
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