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Not every mineral-opacity in the retroperitoneal space is a ureteral stone.

Abdominal radiographs can contain several normal anatomic structures and superimpositions that closely mimic disease. Recognizing these imaging pitfalls is an important part of radiographic interpretation and can help avoid unnecessary diagnostics or incorrect diagnoses.

This carousel explores one of the most common mimics encountered on abdominal radiographs. Swipe through the images and see if you would have recognized it before reaching the final slide.

📌 Keywords: veterinary radiology, abdominal radiographs, ureterolith, ureteral calculi, ureteral stones, deep circumflex iliac vessels, retroperitoneal fat, retroperitoneal anatomy, radiographic interpretation, diagnostic imaging, canine radiology, feline radiology.

Adapted from Vignoli M, Graham J. Atlas of Diagnostic Imaging of Dogs and Cats. Edra Publishing US LLC; 2022. Also from: Thrall & Robertson (2016) and Mühlbauer & Kneller (2013).

Hopefully you'll never need this cheat sheet. But if chemotherapy extravasation happens, you'll be glad you saved it.

Chemotherapy extravasation is an oncologic emergency. Prompt recognition and appropriate management can significantly reduce tissue injury and improve patient outcomes.

Not all chemotherapeutic agents are managed the same way after extravasation. Depending on the drug involved, the goal is to localize and neutralize, disperse and dilute, or simply monitor for mild inflammation.

Why cold for some drugs and warm for others? The answer lies in the drug's mechanism of tissue injury. Drugs like doxorubicin are best localized to prevent further spread, making cold compresses the preferred choice. In contrast, vinca alkaloids are better dispersed, so warm compresses and hyaluronidase help spread the drug and reduce its local concentration, minimizing tissue damage.

This infographic is based on the AAHA Chemotherapy Extravasation Management toolkit and is intended as a quick clinical reference. Always follow your institution's protocols and exercise clinical judgment when managing chemotherapy extravasation.

📄 VetEd Subscribers: A more comprehensive PDF guide, complete with additional explanations and dosages, will be posted in our subscriber group.

Is there a PCV Cutoff for Blood Transfusions in Dogs?

One of the most common questions in practice is: "At what PCV should I transfuse?" The answer is that there isn't a universal threshold.

Although most dogs will benefit from a red blood cell transfusion once the PCV falls below 10–12%, many dogs require transfusion at 13–19%, while others with a PCV above 20% may still need one depending on their clinical condition. The patient's ability to compensate for anaemia varies considerably, making the clinical picture more important than the PCV alone.

To help assess the clinical impact of anaemia, we've created a scoring table adapted from Threlfall and Ekkebus (2025), which evaluates several clinical indicators associated with inadequate oxygen delivery:
• Mucous membrane colour
• Pulse quality
• Heart rate
• Respiratory rate
• Mentation and exercise tolerance

Each parameter is scored from 0 (normal) to 3 (severe). Higher scores suggest that a transfusion is more likely to be indicated, but there is no ADCAS score that automatically mandates transfusion. Instead, it should be interpreted alongside the patient's haematological findings and overall clinical status.

Other Important Considerations

Beyond the ADCAS score, several other factors influence whether a dog is likely to benefit from a red blood cell transfusion:
• Chronicity of anaemia: Dogs with acute anaemia often require transfusion at a higher PCV because compensatory mechanisms have not yet developed, whereas dogs with chronic anaemia may tolerate lower PCVs.
• Mechanism of anaemia: Dogs with ongoing haemorrhage or haemolysis are more likely to require early transfusion than patients with stable regenerative anaemia, where the anaemia may resolve as regeneration continues.
• Comorbidities and oxygen demand: Earlier transfusion may be appropriate in patients with cardiac disease, thrombocytopenia, those undergoing surgery or anaesthesia, or any condition that increases oxygen demand or reduces oxygen delivery.
• Overall prognosis: The expected outcome, quality of life, and treatment goals should always be considered when deciding whether transfusion is appropriate.

Ultimately, transfusion decisions should be based on the patient—not a single laboratory value. PCV provides valuable information, but it is only one piece of the puzzle. Assessing the patient's clinical signs, disease process, chronicity of anaemia, comorbidities, and expected disease progression leads to more informed and individualized transfusion decisions.

Threlfall A, Ekkebus S. Canine blood transfusion in the UK. Part 1: Theory – why, what, when and how? In Practice. 2025;47:452–462.

FIP Antiviral Dosing Cheat Sheet 📌

Need a quick dosing reference? This cheat sheet summarizes the recommended doses of GS-441524 and remdesivir for the different clinical forms of feline infectious peritonitis (FIP), including:

• Effusive (wet) FIP
• Non-effusive (dry) FIP
• Ocular FIP
• Neurologic FIP

📌 Save this post for quick reference in clinical practice.

Coggins S, Černá P. Pharmacologic Approaches to Feline Infectious Peritonitis. Today's Veterinary Practice. 2025;15(4):18–24.
Tasker S, Spiri AM, et al. Viruses. 2026;18(4):452.