title: Intralesional administration of formalin for treatment of epidermal inclusion cysts in five horses.
abstract: Five horses with unilateral epidermal inclusion cysts located in the nasal diverticula were sedated and treated with intralesional injection of neutral-buffered 10% formalin (volume range, 2 to 4.5 mL). After aspiration of the cyst, formalin was injected intralesionally until leakage of fluid around the needle was observed. After several weeks, desiccation of the cyst was evident; it was excised 2 weeks after treatment in 3 horses, digitally removed by the owner of 1 horse, and never removed in 1 horse, because the owner declined further treatment after resolution of the original swelling of the nasal diverticulum. Swelling of the cyst after treatment was observed in all horses; nasal discharge (2 horses) and a mild episode of epistaxis (1 horse) were the only other complications of the treatment. Intralesional administration of formalin appears to be a simple and effective treatment for epidermal inclusion cysts in the nasal diverticula of horses.
authors.affiliation: Comstock Large Animal Hospital, 90 W Laramie Dr, Reno, NV 89521, USA.
authors.forename: Rebecca L
authors.initials: RL
authors.lastname: Frankeny
mesh_terms: D000818:Animals; D004240:Diverticulum / Q000662:veterinary; D004814:Epidermal Cyst / Q000188:drug therapy / Q000473:pathology / Q000662:veterinary*; D005260:Female; D005557:Formaldehyde / Q000627:therapeutic use*; D006734:Horse Diseases / Q000188:drug therapy* / Q000473:pathology; D006736:Horses; D015552:Injections, Intralesional / Q000662:veterinary; D008297:Male; D009666:Nose; D009668:Nose Diseases / Q000188:drug therapy / Q000473:pathology / Q000662:veterinary*
chemical_list: D005557:Formaldehyde