Introduction
Chronic nasal discharge in equids often results from dental disease, infections or anatomical abnormalities. Miniature horses and ponies are particularly predisposed to upper respiratory issues due to their small skulls and disproportionately large teeth. Retained juvenile cranial features may contribute to impaired sinus drainage and recurrent sinusitis. While sino-nasal anatomical abnormalities are rarely described in horses, some reports suggest a developmental origin in young animals with possible breed predisposition. This case illustrates the diagnostic value of computer tomography (CT) and the therapeutic application of diode laser fenestration in managing sino-nasal obstruction.

Case Description
A one-year-old miniature Shetland pony filly presented with an eight-week history of unilateral, nasal discharge unresponsive to prior antimicrobial therapy. Endoscopy on the right side revealed yellow, mucous discharge, a displaced dorsal concha overlapping a hypoplastic ventral concha and malformed sino-nasal drainage anatomy. CT imaging confirmed significant anatomical abnormalities of the right nasal passage including an enlarged dorsal concha, a hypoplastic ventral concha and a deviated nasal septum with right-sided sinus enlargement.

Treatment and Outcome
Initial conservative management with meloxicam and doxycycline proved ineffective. Due to the presence of an anatomical obstruction, diode laser fenestration of the dorsal concha was performed under standing sedation. Using an 810 nm diode laser (15 W, 600 J), a 3 cm drainage window was created to establish communication between the sinus system and the nasal passage. This facilitated effective evacuation of purulent material and allowed for transnasal lavage. Postoperative endoscopy on days 2 and 5 confirmed patency of the fenestration and a marked reduction in mucosal inflammation. The filly showed clinical improvement and was discharged six days postoperatively without the need for additional treatment. At a two-month follow-up she remained free of clinical signs of sinusitis and was reported by the owner to be significantly more energetic.

Conclusion
This case highlights the utility of advanced imaging for diagnosing developmental sino-nasal abnormalities in miniature equids. Diode laser fenestration of the dorsal concha provided a minimally invasive, effective solution for re-establishing sinus drainage and resolving sinusitis.
It offers a viable therapeutic alternative in young miniature horses or ponies whose skull anatomy limits traditional approaches.

Bio
Patricia Trummer-Schug (born 1996) graduated from the University of Veterinary Medicine Vienna in 2021. Following her graduation, she completed a rotating internship at the Equine Clinic of the University of Veterinary Medicine Vienna from 2021 to 2022. She subsequently held a junior surgical position in equine dentistry at the Center for Equine Health and Research. Since 2022, she has combined fundamental research on early-stage osteoarthritis as part of her doctoral thesis with clinical work in equine dentistry at the university clinic.

Use of an axial pattern rotational flap to repair a non-healing head wound in a horse
Dehiscence is a concerning complication for any surgical wound. Surgical repair over the equine sinus can be complicated by many factors including lack of bone support, skin tension, or unresolved sinus infection. Chronic wounds are challenging to repair for the above reasons as well as the presence of fibrosis or scar tissue adjacent to the wound. In this case report, an axial pattern rotational flap and a transpositional flap were used to repair a chronic non-healing wound in a horse.

Learning Objectives
Attendees will be able to:
1. explain reasons for failure of surgical repair
2. describe different types of skin flaps
3. apply an axial pattern flap for repair of a sinus wound in a horse