Ultrasound-guided percutaneous sclerotherapy of a canine hepatic cyst using lower-concentration ethanol: A case report

A 10-year-old female Pomeranian was referred after a hepatic cyst was incidentally identified during a routine health check. Ultrasound-guided simple drainage was initially performed, and cytological examination of the aspirated fluid confirmed a simple cyst. However, the cyst re-expanded to its original size within 2 weeks. Therefore, ultrasound-guided percutaneous sclerotherapy was elected using lower-concentration ethanol (83%), a readily available medical disinfectant, rather than conventional high-concentration ethanol. Approximately 50% of the aspirated volume was replaced with 83% ethanol and retained for 20 min to achieve effective epithelial ablation. Post-procedural follow-up revealed a transient increase in cyst size and serum alanine aminotransferase levels on day 3, attributed to the inflammatory sclerosing process; however, these changes resolved spontaneously by day 20. Complete cyst regression was confirmed by day 60, with no recurrence during the 1-year follow-up. This case suggests that lower-concentration ethanol (83%) is a feasible, safe, and effective sclerosing agent for canine hepatic cysts and may represent a practical option in clinical settings where high-concentration ethanol is unavailable.