Assessing Nasal Soft-Tissue Envelope Thickness for Rhinoplasty

Abstract

IMPORTANCEPreoperative assessment of nasal soft-tissue envelope (STE) thickness is an important component of rhinoplasty that presently lacks validated tools.OBJECTIVE To measure and assess the distribution of nasal STE thickness in a large patient population and to determine if facial plastic surgery clinicians can predict nasal STE thickness based on visual examination of the nose. DESIGN, SETTING, AND PARTICIPANTSThis retrospective review and prospective assessment of 190 adult patients by 4 expert raters was conducted at an academic tertiary referral center. The patients had high-resolution maxillofacial computed tomography (CT) scans and standardized facial photographs on file and did not have a history of nasal fracture, septal perforation, rhinoplasty, or other surgery or medical conditions altering nasal form. Data were analyzed in March 2019.MAIN OUTCOMES AND MEASURES Measure nasal STE thickness at defined anatomic subsites using high-resolution CT scans. Measure expert-predicted nasal STE thickness based on visual examination of the nose using a scale from 0 (thinnest) to 100 (thickest). RESULTSOf the 190 patients, 78 were women and the mean (SD) age was 45 (17) years. The nasal STE was thickest at the sellion (mean [SD]) (6.7 [1.7] mm), thinnest at the rhinion (2.1 [0.7] mm), thickened over the supratip (4.8 [1.0] mm) and nasal tip (3.1 [0.6] mm), and thinned over the columella (2.6 [0.4] mm). In the study population, nasal STE thickness followed a nearly normal distribution for each measured subsite, with the majority of patients in a medium thickness range. Comparison of predicted and actual nasal STE thickness showed that experts could accurately predict nasal STE thickness, with the highest accuracy at the nasal tip (r, 0.73; prediction accuracy, 91%). A strong positive correlation was noted among the experts' STE estimates (r, 0.83-0.89), suggesting a high level of agreement between individual raters.CONCLUSIONS AND RELEVANCE There is variable thickness of the nasal STE, which influences the external nasal contour and rhinoplasty outcomes. With visual analysis of the nose, experts can agree on and predict nasal STE thickness, with the highest accuracy at the nasal tip. These data can aid in preoperative planning for rhinoplasty, allowing implementation of preoperative, intraoperative, and postoperative strategies to optimize the nasal STE, which may ultimately improve patient outcomes and satisfaction.LEVEL OF EVIDENCE NA.

Reconstruction of Alar Lining and Nostril Base by Oral Mucosal Flap on Muscular Pedicle

“…Although visual analysis of the nasal base by experts could predict the improvement but we did measurements by ruler in millimeter to find out evident outcome data. 12 The comparison of visual and photographic nasal patterns in this study showed a restoration to normal, almost like contralateral side of nasal opening in all cases. This surgical technique achieved nasal ventilation in a balanced pattern and has decreased nasal resistance for the airflow through the treated nasal opening, then increased the capacity of upper airway passage.…”

Predicting Nasal Soft Tissue Envelope Thickness for Rhinoplasty: A Model Based on Visual Examination of the Nose

“…As described by Dey et al, the nasal STE was thickest at the sellion (6.7 ± 1.7 mm), thinnest at the rhinion (2.1 ± 0.7 mm), and then became thicker again over the supratip (4.8 ± 1.0 mm) and nasal tip (3.1 ± 0.6 mm), and thinned over the columella (2.6 ± 0.4 mm). 10 For each subsite, nasal STE thickness follows a near-normal distribution with the majority of patients in a medium thickness range. The mean nasal STE thickness was calculated for each nose by averaging the thickness at each subsite.…”

“…High-resolution maxillofacial protocol CT scans with 1-mm slices were read by two neuroradiology fellows using a standardized protocol previously described by Dey et al 10 In-house radiology measurement annotation software (QREADS) was used to measure the nasal STE thickness at the following anatomic sites for each patient: sellion, rhinion, supratip including the interdomal fat pad, 13 nasal tip, and columella. Mean nasal STE thickness was calculated by averaging the five subsite measurements for each nose.…”

“…Preoperative CT scans have been used to measure nasal STE thickness by Cho et al in a Korean population, Dey et al in a primarily Caucasian population, Jomah et al in a Saudi population, and Eggerstedt et al in a mixed race population. 1,10-12 Kosins et al used preoperative high-frequency ultrasound to measure nasal STE thickness in patients undergoing rhinoplasty. 2 The majority of facial plastic surgeons primarily use visual examination with or without palpation to estimate nasal STE thickness preoperatively.…”

“…Dey et al have shown that experts in facial plastic surgery can accurately predict nasal STE thickness with visual examination of the nose. 10…”