Anatomy and Surgical Approaches to the Rabbit Nasal Septum

Abstract

Importance: The rabbit is the primary animal model used to investigate aspects of nasal surgery. Although several studies have used this model, none has provided a comprehensive analysis of the surgical anatomy and techniques used to gain access to the rabbit nasal fossae and septum.

Objective: To describe and optimize the surgical anatomy and approach to the rabbit nasal vault and septal cartilage.

Design, setting, and participants: In an ex vivo animal study conducted at an academic medical center, preliminary cadaveric dissections were performed on rabbit head specimens to establish familiarity with relevant anatomy and rehearse various approaches. Live Pasteurella-free New Zealand white rabbits (3.5-4.0 kg) were used to further develop this surgical technique developed here. Access of the nasal vault was gained through a midline nasal dorsum incision and creation of an osteoplastic flap with a drill. Submucosal resection was performed with preservation of the mucoperichondrium. All rabbits were monitored daily for 4 weeks in the postoperative period for signs of infection, pain, and complications. The study was conducted from June 1, 2014, to December 1, 2014.

Main outcomes and measures: Surgical anatomy and techniques used to gain access to the rabbit nasal vault and harvest septal cartilage.

Results: Four Pasteurella-free New Zealand white rabbits (Western Organ Rabbit Co), ranging in age from 9 to 12 months and weighing between 3.5 and 4.0 kg, were used in this study. Initial dissections demonstrated the feasibility of harvesting septal cartilage while preserving the mucoperichondrial envelope. Access to the nasal vault through this 3-osteotomy approach allowed for maximal exposure to the nasal cavity bilaterally while maintaining the integrity of the mucoperichondrium following septal cartilage harvest. The maximum amount of bulk, en bloc, cartilage harvested was 1.0 × 2.5 cm. Following surgical dissection, all animals maintained adequate airway patency and support to midface structures. Furthermore, all specimens preserved the integrity of the mucoperichondrium, septum, vascular anatomy, and airway dynamics. No operative complications, postoperative airway compromise, or infections were observed.

Conclusions and relevance: Access to the rabbit nasal vault and septal cartilage is feasible through a variety of surgical approaches and techniques. To date, this is the first study to meticulously document and review the surgical approaches to the rabbit nasal cavity. This approach describes a novel, 3-osteotomy method of accessing the nasal cavity bilaterally and successfully harvesting rabbit septal cartilage in a submucoperichondrial plane. The ability to preserve native anatomy and function allows for improved outcomes in translational and animal guided clinical research.

Level of evidence: NA.

Figure 1.. Bony and Mucosal Depictions of the Snout Nasal Cavity

Dorsal (A) and coronal (B) views demonstrate the humanlike qualities of the snout and paranasal structures. Adapted with permission from Evans and de Lahunta.

Figure 2.. Dissection of the Soft-Tissue Envelope

A, Planned dorsal nasal incision. B, Elevation of skin flaps bilaterally. C, Harvesting a right-based periosteal flap.

Figure 3.. Three-Osteotomy Window Illustration and Its Axis

Figure 4.. Access to the Nasal Cavity

Cottle elevator to rotate and outfracture the nasofrontal osteoplastic flap (A), providing exposure to the nasal cavity and septal cartilage (B).

Figure 5.. Rabbit Septal Cartilage

Approximately 1 x 2.5 cm.