Dorsal Hump Reduction Based on the New Ethmoidal Point Classification: A Clinical and Radiological Study of the Keystone Area in 138 Patients

Abstract

Background Hump resection often requires reorganization of the keystone area. Objectives The authors sought to describe the importance of the point where the perpendicular plate of ethmoid joins the septal cartilage (SC) and the nasal bones (NB) (Ethmoidal point [E-point]) for hump resection surgical planning. Methods Measurements from mid-sagittal slices in nasal computed tomography scans taken in adult Caucasian patients between January 2015 and December 2018 were compared between patients seeking primary rhinoplasty due to a nasal hump and patients not seeking rhinoplasty (control group). Patients with previous nasal surgery or trauma, genetic or congenital facial disorders, and high septal deviation were excluded. The length of overlap between NB and SC was compared between the 2 groups. The location of the E-point in relation to the beginning of the nasal hump in the cephalocaudal direction was documented in the patients seeking rhinoplasty. Results The study population included 138 patients, 69 seeking and 69 not seeking rhinoplasty (96 females). The mean age was 32.9 years (range, 18-55 years). The length of overlap between NB and SC was similar between both groups (11.7 ± 3.3 vs 10.8 ± 3.3; P = 0.235). The E-point was located before the beginning of the nasal hump in 97% (67/69) of nasal hump patients, and it could be found a mean distance of 2.3 (±2.3) mm cephalic to the latter. Conclusions As a rule, the perpendicular plate of the ethmoid does not contribute to the nasal hump; therefore, only in exceptional cases should this be addressed while performing dorsal reduction. Level of Evidence: 3

Ferreira-Ishida Technique: Spare Roof Technique B. Step-by-Step Guide to Preserving the Bony Cap While Dehumping

“…The E-point, introduced by Ferreira et al, 8 represents the point where the perpendicular plate of the ethmoid meets the undersurface of the nasal bones. The author has found that 97 percent of the humps begin after this E-point.…”

Middle Vault Changes After Humpectomy by Spare Roof Technique Versus Component Dorsal Hump Reduction

“…4,[8][9][10][11] Cephalically the fused SC and ULCs join the inferior surface of the NBs in keystone area. 3,8,10 The lateral border of the ULCs lacks any skeletal support but instead joins the bones of the pyriform aperture through the pyriform ligament. 2,4 Inferiorly the ULCs join the lower lateral cartilages (LLC), in the scroll complex region, where a longitudinal scroll ligament connects them.…”

“…2 Since most hump reduction techniques require a modification of the middle vault, these may bring significant functional changes. 3 Structured rhinoplasty humpectomy techniques, such as the component dorsal hump reduction (CDHR), involve amputation of the bony and/or cartilaginous hump followed by reconstruction of the cartilaginous roof with either spreader grafts or spreader flaps. 4 Dorsum preservation rhinoplasty techniques aim to avoid the need for reconstruction of the middle roof to preserve original dorsal aesthetic lines.…”

Preservation Rhinoplasty: Assessment of Anatomical Safe Boundaries on Computed Tomography

“…Consequently, they reported that the perpendicular plate did not consist of the nasal hump. 26 Moreover, the relationship of the nasal hump to the cribriform plate was not mentioned.…”