An Anatomic Analysis of the Bony Vault: From the Perspective of Osteotomy in Rhinoplasty

Overview

Osteotomy means deliberately cutting or fracturing the nasal bones to narrow or straighten the bony part of the nose. The authors asked how thick the bone actually is along the paths a surgeon cuts. They reviewed preoperative three dimensional facial bone computed tomography images from 250 patients scheduled for primary rhinoplasty, sorted the noses into symmetric and asymmetric bony vaults, and measured thickness at set points.

Sections of note

• Design: retrospective measurement study using preoperative CT images from 250 primary rhinoplasty patients.
• Thickness was measured at three points along the lateral osteotomy path and two points each along the medial and intermediate paths.
• 88 patients (35.2 percent) had an asymmetric bony vault; 162 (64.8 percent) had a symmetric one.
• The bony vault was thickest at the middle level of the lateral osteotomy path.
• Bone was thicker in male patients at every measured point on the medial and lateral paths.
• In asymmetric vaults the deviated side was thicker than the opposite side along all osteotomy paths, and thicker than in symmetric vaults at the lateral midpoint, while the opposite side was thinner.

What it means for a patient

• Bone thickness is not uniform, so a surgeon planning to narrow or straighten the bony nose has a reason to look at imaging first.
• Men and people with a crooked bony nose tend to have thicker bone on the deviated side, which is the hardest place to control a fracture.
• This is an anatomy measurement study. It reports no surgical outcomes, complication rates or follow up, and no comparison of techniques.

Why this paper matters

Bony vault work is one of the least reversible steps in rhinoplasty, and an uncontrolled fracture can leave a step or asymmetry. This paper supplies measured thickness data to inform where more force or a different instrument may be needed. Whether preoperative CT measurement actually improves surgical results is not tested here.

Terms

• Osteotomy: a planned cut or controlled fracture of bone.
• Bony vault: the upper third of the nose formed by the paired nasal bones.
• Lateral osteotomy: a cut along the side wall of the bony nose, used to move it inward.
• Medial osteotomy: a cut near the midline of the bony nose.
• Primary rhinoplasty: a first nose operation, with no prior nasal surgery.