Computed Tomography Based Classification of Nasal Bone Shape and Thickness for Osteoplasty: The Avellaneda System

Successful rhinoplasty relies heavily on understanding the anatomical diversity of the nasal bones. Variability in nasal bone shape and thickness directly influences the technical complexity and outcomes of osteoplasty; the aim of this study was to develop and validate a computed tomography (CT)-based classification system of nasal bone shape and thickness to guide surgical planning in nasal osteoplasty and optimize patient-specific outcomes.

A prospective study was conducted on 125 patients who underwent preoperative CT scans between 2021 and 2024. Nasal bone shape was categorized as concave, planar, or convex, and thickness as thin (<2 mm), medium (2-4 mm), or thick (>4 mm); these were combined into 9 possible subtypes. Open rhinoplasty with tailored osteoplasty was performed in all patients, without osteotomies. Outcomes were assessed with CT comparisons and the FACE-Q Rhinoplasty Module at 3, 6, and 12 months.

CT analysis revealed substantial anatomical variability: 47.2% of right nasal bones were convex, whereas only 24% were concave; 51.2% had medium thickness, and 45.6% were thick. The most common Avellaneda types were 3B (convex-medium) and 3C (convex-thick). No unintended nasal bone fractures occurred. Patient satisfaction improved significantly postoperatively.

The Avellaneda classification offers a novel, pragmatic framework to individualize nasal osteoplasty based on CT findings; integrating bone shape and thickness allows surgeons to tailor their technique to the patient's anatomy, avoid intraoperative fractures, and enhance surgical precision. This system may improve outcomes, promote surgical safety, and serve as a reference for future refinements in rhinoplasty.