Tear Film health in French Bulldogs: what the latest study using OSA-Vet® reveals

February 12, 2026

French Bulldogs have become one of the most popular dog breeds worldwide, but their unique facial anatomy also predisposes them to ocular surface disorders. A recently published study in Frontiers in Veterinary Science investigates tear film characteristics in healthy French Bulldogs and compares them with non-brachycephalic dogs, using a comprehensive diagnostic approach that includes the OSA-Vet® system.

The results highlight qualitative differences in tear film integrity that could contribute to eye surface disease in this breed and demonstrate the clinical value of objective tear film diagnostics like interferometry, NIBUT, and meibography with OSA-Vet®.

Why Tear Film matters in dogs

The tear film plays a crucial role in maintaining ocular surface health, lubricating the eye, protecting against infection, and ensuring clear vision. Disruptions in tear film quality or stability can lead to dry eye disease and other surface disorders, especially in breeds with altered facial conformation like French Bulldogs.

Veterinarians distinguish between two main types of dry eye:

• Aqueous deficient dry eye (ADDE): insufficient tear production
• Evaporative dry eye (EDED): excessive tear evaporation due to a deficient lipid layer or film instability

This study focused on identifying qualitative tear film abnormalities, especially evaporative dry eye signs.

How the study was conducted

Researchers examined a group of healthy French Bulldogs alongside healthy dogs of mesocephalic and dolichocephalic breeds (non-brachycephalic controls). All dogs underwent:

• Full ophthalmic exam
• Tear film osmolarity measurement
• Comprehensive tear film analysis with OSA-Vet®, including:
  • Interferometry (lipid layer assessment)
  • Non-invasive tear break-up time (NIBUT)
  • Tear meniscus height (TMH)
  • Meibography (Meibomian gland evaluation)

Tear osmolarity was also measured with a separate device to explore whether this could help differentiate dry eye types.

Key findings

The study revealed several consistent differences between French Bulldogs and non-brachycephalic dogs:

1. Shorter Tear Film Stability (NIBUT)
   French Bulldogs had significantly lower NIBUT values, indicating a tear film that breaks up earlier after blinking, a hallmark of evaporative dry eye disease.
2. Lower Interferometry Scores
   Interferometry with OSA-Vet® showed reduced lipid layer quality in French Bulldogs, meaning the protective oily layer was thinner or less stable, another sign pointing toward evaporative dry eye.
3. Higher Tear Meniscus Height
   Although these dogs didn’t produce less tear volume, the higher tear meniscus height suggests reflex tearing, likely a response to rapid tear evaporation and eye surface irritation.
4. Similar Tear Osmolarity
   Contrary to some expectations, tear osmolarity did not differ significantly between groups, indicating that tear chemistry alone may not distinguish dry eye types in this context.
5. Meibomian Gland Differences
   Meibography also suggested greater Meibomian gland changes in French Bulldogs, potentially contributing to the instability of the lipid layer.

What this means for vets and pet owners

The study’s findings show that:

• Healthy French Bulldogs often show signs of evaporative dry eye disease (EDED) even without overt clinicalcomplaints.
• Standard tear volume tests may not be enough to detect subtle tear film dysfunction in brachycephalic dogs.
• Advanced diagnostics like OSA-Vet® interferometry, NIBUT, and meibography add significant value for earlydetection and tailored management of tear film disorders.

These insights can help veterinarians identify tear film deficiencies earlier and optimize treatment plans before secondary ocular surface disease develops.

Clinical implications and future perspectives

The findings of this study contribute to a better understanding of tear film dynamics in French Bulldogs and highlight how breed-related anatomical features can influence ocular surface health, even in dogs considered clinically healthy.

The results suggest that tear film instability and lipid layer alterations may be present before the onset of overt clinical signs, reinforcing the importance of a qualitative assessment of the tear film in brachycephalic breeds. In this context, diagnostic approaches that evaluate tear film stability, lipid layer characteristics, and Meibomian gland morphology provide additional information compared to tear quantity measurements alone.

From a clinical perspective, these insights may support earlier identification of dogs at risk of developing ocular surface disease and encourage more targeted monitoring strategies in predisposed breeds.

This study published in Frontiers in Veterinary Science offers a comprehensive analysis of tear film characteristics in French Bulldogs compared to non-brachycephalic dogs.

These findings underline the value of a multimodal diagnostic approach to tear film evaluation and contribute to a more nuanced understanding of ocular surface health in brachycephalic dogs. Further research will be useful to clarify the clinical relevance of these alterations over time and their role in the development of ocular surface disease.

This article is based on the peer-reviewed publication: Tear film characteristics in French Bulldogs compared to non-brachycephalic dogs (Frontiers in Veterinary Science, 2025).
A downloadable PDF of the original publication is attached here.