Do Experts Always Agree About MRIs?

Hello, Summarians!

Do you ever wonder about the interpretation of complex information? Interpreting that information into a coherent thought process can be overwhelming with all the technological advances we are making.

That’s why we have experts right? Well, the answer is a definite maybe… I get it. We can’t agree about everything but this study helps me put the big picture into context.

We need to be careful about how we utilize all this information when we make decisions because humans are well…human.

This newsletter is an attempt to help us all cope with the deluge of information we face every day. It usually contains 3 summaries and citations related to animal health.

Ear Cleaners for Biofilm

This study investigates the in vitro efficacy of different ear cleansers as antimicrobial adjuvants for canine otitis externa, an inflammatory disease of the external ear that can be complicated by biofilm formation. The research focused on three compounds—Otoflush, NAC, and Triz-EDTA—with Otoflush containing PHMB and EDTA showing the most promising results by achieving the lowest minimum biofilm eradication concentrations (MBEC) across a broad range of pathogens, including bacteria such as Staphylococcus pseudintermedius, Pseudomonas aeruginosa, and yeast like Malassezia pachydermatis. PHMB works by binding to bacterial membranes, causing leakage of cellular components and condensation of chromosomes, while EDTA disrupts the outer membrane of Gram-negative bacteria, facilitating antimicrobial action. Although NAC demonstrated antibiofilm activity, it required higher concentrations than those typically recommended and may pose ototoxic risks at elevated doses. Meanwhile, Triz-EDTA was largely ineffective against Gram-negative pathogens at the concentrations tested, though it did show activity against some Gram-positive strains. Overall, the findings suggest that when applied directly to the canine ear canal, Otoflush is likely to be an effective adjuvant, particularly in chronic or treatment-resistant cases where biofilm-associated resistance is a significant concern, even though further in vivo studies are needed to confirm these results. 

Savaliya BF, Kim S, Veltman T, Trott DJ. Comparison of the in vitro antibiofilm activities of otic cleansers against canine otitis externa pathogens. Vet Dermatol. 2025; 36: 148–158. https://doi.org/10.1111/vde.13331 

Bottom line — Good information.

MRI Agreement in Foot Pathology

This exploratory study assessed how consistently experienced observers evaluate equine foot pathology on MRI. Ten experienced observers reviewed 15 MRI studies and graded pathology in seven key anatomical structures on a four-point scale (from no pathology to severe pathology) while also rating their confidence in each assessment. The findings revealed that agreement on the mere presence or absence of pathology was generally poor to fair across structures—with the navicular bone being the notable exception, achieving moderate agreement (k = 0.52). When accounting for the ranking of pathology severity, concordance varied considerably (with Kendall’s coefficient ranging from 0.19 for the distal interphalangeal joint to 0.70 for the navicular bone), and agreement was highest at the extreme ends of the grading scale. Despite observers reporting moderate to high confidence in their assessments, the study highlights significant variability in MRI interpretation of equine foot pathology, underscoring potential clinical implications. 

Byrne CA, Voute LC, Marshall JF. Interobserver agreement during clinical magnetic resonance imaging of the equine foot. Equine Vet J. 2025; 57(2): 406–418. https://doi.org/10.1111/evj.14126 

Bottom line — We need further assessment of this issue.

Predicting Disease Risk in Animals

The paper discusses the emerging use of polygenic risk scores (PRSs) in predicting disease risk for companion animals and contrasts this application with the more established use of PRSs in human health and livestock. It explains that PRSs, which quantify the cumulative effect of thousands of genetic variants on disease risk, have been widely adopted in human medicine due to extensive genome-wide association studies and robust phenotypic databases. In contrast, companion animal research, particularly in dogs, faces significant challenges such as smaller sample sizes, limited genomic resources, and considerable genetic heterogeneity across breeds. These breed-specific differences complicate risk prediction because genetic markers and linkage disequilibrium patterns may not transfer well from one breed to another. 

The review outlines the process of generating a PRS, which involves using a training set with both genetic and phenotypic data to derive weighted genetic markers, and then applying these weights to predict disease risk in a test population. Various studies in dogs are highlighted, including those predicting hip dysplasia, cruciate ligament rupture, and other conditions, where different models such as genomic BLUP, Bayesian methods, and machine learning have been employed. The accuracy of these models can vary significantly, often depending on the genetic architecture of the disease and the breed-specific characteristics. 

Furthermore, the paper examines the potential of using multiancestry prediction approaches, which have shown promise in human studies, to improve PRS accuracy in dogs by integrating data from multiple breeds. It also underscores the need for large-scale, high-quality phenotypic databases and comprehensive genomic resources, such as those provided by initiatives like the Dog10K Genome Project, to advance the field. Despite the current limitations, the authors are optimistic that ongoing technological and methodological advances will eventually enhance the precision of PRS predictions, leading to improved veterinary care and more informed breeding decisions. 

Momen, M., & Muir, P. (2025). Polygenic risk score prediction of complex diseases in companion animals: prospects, opportunities, and challenges. American Journal of Veterinary Research https://doi.org/10.2460/ajvr.25.01.0018. 

Bottom line — Useful for people and livestock but not as useful for smaller pets yet.

Just putting things in perspective …