Anatomical Study of the Chinese Nasal Keystone Region

Abstract

Background The keystone region is an important anatomical structure to consider in rhinoseptoplasty, because there are few published data regarding the keystone region in Chinese noses. Objectives The authors sought to describe the anatomy of the Chinese nasal keystone region and provide useful knowledge for rhinoseptoplasty. Methods Sixteen cadaveric heads (11 males, 5 females) were dissected, measured, and then compared with previously published data. Results Both the nasal bone caudal margin and nasal bone-upper lateral cartilage overlapping area displayed 5 distinct shapes, and the upper lateral cartilage showed 4 distinct shapes. The nasal bone-upper lateral cartilage overlap was 6.47 mm ± 2.50 in the midline, 3.53 mm ± 2.23 on the left, and 3.81 mm ± 2.56 on the right. The length of the whole quadrangular cartilage was 25.63 mm ± 4.27; 25% ± 8% was overlapped by the nasal bone. The height of the caudal quadrangular cartilage was 18.14 mm ± 3.44, and the width of the nasal bone-upper lateral cartilage articulation was 23.56 mm ± 8.30. The upper lateral cartilage-quadrangular cartilage complex stayed in position on the maxillary crest and nasal spine, even after being dissected from the nasal bone, perpendicular plate of the ethmoid bone, and vomer. Bilateral perichondrial-periosteal mucosa detached from the nasal septum. Conclusions We report various anatomical and structural features of the Chinese keystone region, which will be valuable for rhinoseptoplasty planning in Chinese patients.

Surgical anatomy for Asian rhinoplasty: Part II

“…In Asian reports, the cephalocaudal length of the overlapping area between the upper lateral cartilage and the nasal bone was 7 mm (range, 4-10 mm) in the midline, and 3.1 mm (range, 0-7 mm) in the paramedian area in a study by Kim et al [37] involving the dissection of 18 Korean cadavers. Han et al [38] reported that the nasal bone-upper lateral cartilage overlap was 6.47 ± 2.50 mm in the midline, 3.53 ± 2.23 mm on the left side, and 3.81 ± 2.56 mm on the right side in a study of 16 Chinese cadavers. In summary, the length of overlap between the nasal bone and cartilaginous septum tends to be shorter in Asians according to previous research.…”

“…16). In particular, the cartilage beneath the keystone area should be maximally preserved to maintain the stability of septal support and to prevent complications such as saddle nose deformity [38]. According to Mau et al [49], a wider L-strut and a greater extent of overlap in the junction at the keystone will improve stability against tensile stress.…”