Meet The Author
October 2026
Helen Dirrig BVetMed MVetMed DACVR DECVDI FHEA MRCVS
I am half French and grew up there, but ended up studying and working as a vet in the UK, where I still live. I divide my time between my lecturer role at the Royal Veterinary College and teleradiology work at VetCT Ltd, whilst also juggling family life with my husband and two young children. I love sport and exercise, especially volleyball and yoga, and try to spend as much time outside as possible!
Computed tomographic features of presumed normal palatine tonsils in 140 dogs
N. Leong, R. Drees, H. Dirrig
This paper was the result of an undergraduate student research project that was supervised by one of the co-authors (Dr. Randi Drees). We had an excellent, very motivated student and a large database to use. I find CT of the head particularly interesting, and tonsils hadn't been described in this modality yet.
What is the primary knowledge gap your study aims to address?
CT features of normal tonsils had not been described before. With the huge increase in the use of CT we thought it would be a useful area to investigate, particularly as there are sometimes features that people may question (air or mineralisation in the fossa).
The Study Design
The paper was designed as a retrospective descriptive study, using the head CT studies (acquired at the Royal Veterinary College) of dogs without tonsillar disease, in order to describe the features of presumed normal palatine tonsils. Qualitative and quantitative features were assessed and we also investigated the relationship between tonsillar size and age, body weight, and head conformation.
What are the main study results?
All palatine tonsils could be identified, but just over half were poorly differentiated from adjacent soft tissues. Many tonsillar fossae contained gas, and a small number contained mineral foci. A mean tonsillar size was established and size was found to be negatively correlated with age and positively correlated with body weight. No differences were found between brachycephalic and normocephalic breeds.
Were there any unexpected results or challenges during your research?
Expected challenges and limitations came from the retrospective study design and lack of standardization of patient position and contrast timing, in particular. There are also always challenges when introducing measurements into a study and making sure these are repeatable. It was interesting to note that just over half of the tonsils could not be delineated well enough to be measured, and deciding what the cut-off for good differentiation would be was challenging at times.
Takeaways from this study
Hopefully this study gives clinicians an idea of what to expect when assessing canine tonsils, and gives an idea of prevalence for certain features (gas and mineral in the fossa). Of note, the tonsillar size range was relatively broad and there was overlap between weight categories, with only mm differences between groups, which means distinguishing normal from abnormal remains a challenge.
What future directions would you like to explore based on this study?
As with most descriptive studies of presumed normality, this serves more as a stepping stone towards further work, such as correlation with histopathology and assessing various tonsillar pathologies.
