Application of a Novel 3D-Printed Nasal Plug as a Conservative Treatment for Empty Nose Syndrome.

OBJECTIVE: Empty nose syndrome (ENS) is commonly treated by surgery, albeit with limited success. Herein, we introduce our experience of applying a newly developed "3D-printed nasal plug" as an alternative conservative treatment modality. METHODS: This retrospective study included 20 patients (14 males, 6 females; mean age 46.5 ± 13.5 years) with ENS who underwent the application of the 3D-printed nasal plug at Asan Medical Center between June 2022 and May 2023. Symptom improvement was assessed by Empty Nose Syndrome 6-Item Questionnaire (ENS6Q) before and after applying the nasal plug. Clinical results, such as duration and frequency of plug use, discomfort, and level of satisfaction, were investigated. RESULTS: The mean follow-up duration was 40.3 ± 24.2 weeks. The average duration of nasal plug usage was 10.8 h per day and 5.3 days a week. The ENS6Q scores improved from 19.6 ± 4.6 to 6.8 ± 5.1 (mean reduction 12.8 ± 5.9) after 30 minutes of wearing. Symptom "nose feelings too open" was improved most by a score of 3.0 ± 1.5 (p < 0.001). Thirteen patients (65.0%) reported that the effectiveness of the plug, initially confirmed at the first wearing, was well maintained during the entire follow-up. Four patients (20.0%) wore the nasal plug uninterruptedly throughout the week, whereas nine patients (45.0%) wore it intermittently as needed. Frequently reported complaints with plug usage were 'displacement of the plug' and 'cosmetic concerns' about the visible hook portion. CONCLUSION: A 3D-designed nasal plug can be a useful conservative treatment option for ENS patients. LEVEL OF EVIDENCE: 4 Laryngoscope, 2024.

Efficacy and feasibility of a forehead flap surgical guide for nasal reconstruction.

For successful nasal reconstruction using a forehead flap, three-dimensional (3D) nasal defects need to be translated into a two-dimensional (2D) forehead surface. For this study, a patient-specific 3D-printed forehead flap guide that could precisely translate a virtually simulated nasal shape into a 2D flap template was developed. The study aimed to evaluate the feasibility and efficacy of a 3D-printed forehead flap guide for nasal reconstructions. The 3D nasal surface was scanned using a 3D camera, and a 'digital clay' process was performed to correct the nasal deformity. The 3D morphology was flattened into a 2D forehead flap guide. The guide was 3D-printed and used for the forehead flap design. Photographic records were used to conduct anthropometric and aesthetic evaluations. Between October 2016 and August 2020, forehead flaps were performed using the forehead flap guide (guide group) and traditional templating method (control group) in 16 and 15 patients, respectively. The alar shape was more symmetric in the guide group than in the control group, with smaller right-to-left differences in alar width (p = 0.01) and height (p = 0.05). Regarding aesthetic evaluations, nose contour (p = 0.02) and nasal symmetry (p = 0.033) were better in the guide group than in the control group. The mean operative time was significantly shorter (91.9 ± 10.7 min) in the guide group than in the control group (116.4 ± 13.6 min) (p = 0.001). Our findings suggest that a 3D-printed forehead flap surgical guide can be effectively used in nasal reconstruction to reduce operative time and improve aesthetic outcomes.

Dorsal Augmentation Using a Glued Diced Cartilage Graft Fashioned with a Newly Developed Mold in Asian Rhinoplasty.

BACKGROUND: In dorsal augmentation, costal cartilage can be used in a number of different ways: monobloc, fascia wrapped, or glued diced cartilage grafting (GDCG). The authors developed a mold to make the use of GDCG more convenient. This report describes their experience with GDCG using a novel mold for dorsal augmentation. METHODS: The study involved 80 patients who underwent dorsal augmentation with the molded GDCG. Facial photographs and medical records were reviewed to assess patient satisfaction and postoperative complications. For the 23 patients who had three-dimensional scanned imaging, dorsal widths and dorsal heights at the radix and rhinion levels were measured to investigate changes in the implants over time. Resorption of the graft was assessed comparing the 3-month postoperative photograph with the latest photograph taken at the last follow-up (at least 1 year after the surgery). Serial changes of the dorsum were assessed with three-dimensional scanned images. RESULTS: A total of 66 patients (82.5 percent) were satisfied with their surgical outcomes. Complications were encountered in 19 patients (23.8 percent) and eight revision procedures (10 percent) were performed. One patient underwent revision surgery because of resorption of the GDCG. Analysis using a three-dimensional scanning device showed a significant increment of the dorsal height ( p < 0.05) without dorsal widening when comparing preoperative with 1-year postoperative follow-up data. There were no significant reductions in dorsal height between postoperative 3 months and 1 year. CONCLUSION: The use of a novel mold for shaping glued diced cartilage appears to be a useful technique for dorsal augmentation in rhinoplasty. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

The mechanical characteristics and performance evaluation of a newly developed silicone airway stent (GINA stent).

Central airway obstruction (CAO) can be attributed to several benign or malignant conditions. Although surgery is the preferred therapeutic option for the management of CAO, bronchoscopic treatment can be performed in scenarios where the surgical procedure is not possible. Recent years have witnessed several improvements in the field of bronchoscopic treatment, especially with regard to airway stents. Current research involves new attempts to overcome the existing shortcomings pertaining to the stents (migration, mucostasis, and granulation tissue formation). The authors have recently developed a new silicone airway stent (GINA stent) with an anti-migration design, dynamic structure that enables the reduction of stent cross-sectional area, and radio-opacity. The present study aimed to evaluate the mechanical characteristics and performance of the novel GINA stent using a porcine tracheal stenosis model. In the current study, all the tests involved the comparison of the GINA stent [outer diameter (OD, mm): 14; length (L, mm): 55] with the Dumon stent (OD: 14; L: 50). The mechanical tests were performed using a digital force gauge, in order to determine the anti-migration force, expansion force, and flexibility. The present study evaluated the short-term (3 weeks) performance of the two stents after implantation [GINA (n = 4) vs. Dumon (n = 3)] in the porcine tracheal stenosis model. The results pertaining to the comparison of the mechanical properties of the GINA and Dumon stents are stated as follows: anti-migration force (18.4 vs. 12.8 N, P = 0.008); expansion force (11.9 vs. 14.5 N, P = 0.008); and flexibility (3.1 vs. 4.5 N, P = 0.008). The results pertaining to the comparison of the short-term performance of the GINA and Dumon stents are stated as follows: mucus retention (0/4 vs. 0/3); granulation tissue formation (0/4 vs. 0/3); and migration (1/4 vs. 2/3). The GINA stent displayed better mechanical properties and comparable short-term performance, compared to the Dumon stent.

Clinical Application of a Patient-Specific, Three-Dimensional Printing Guide Based on Computer Simulation for Rhinoplasty.

BACKGROUND: A practical application of three-dimensional printing technology has been considered a difficult area in rhinoplasty. However, the patient-specific three-dimensionally printed rhinoplasty guide based on the simulation program the authors developed could be a solution for minimizing the gap between simulation and actual surgical results. The aims of this study were to determine how a three-dimensional rhinoplasty guide based on three-dimensional simulation would link the patient to the surgeon to investigate its effectiveness. METHODS: Fifty patients who underwent rhinoplasty between January of 2017 and February of 2018 were included in this study. The patients were consulted about the desired shape of their nose based on preoperative three-dimensional photography. The confirmed three-dimensional simulation was sent to a manufacturing company for three-dimensionally printed rhinoplasty guides. In the guide group, rhinoplasty was performed based on the three-dimensionally printed rhinoplasty guide, and in the control group, procedures were performed based on the surgeon's intuition. RESULTS: The intraclass correlation coefficient test for comparing the simulated and postoperative measurements showed higher correlation in the three-dimensional printing guide group: higher correlation 11.3 percent in nasal tip projection, 21.6 percent in dorsum height, and 9.8 percent in nasolabial angle. The postoperative result of the nasal dorsum had a statistically significant difference between the two groups (p < 0.05). CONCLUSIONS: This study demonstrated the usefulness of the three-dimensionally-printed rhinoplasty guide, which delivers the preoperative simulated image in the actual clinical practice of rhinoplasty. This approach could cause a paradigm shift in simulation-based rhinoplasty. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, III.

Comprehensive Three-Dimensional Technology Strategies for Autologous Free Fat Graft in Parry-Romberg Syndrome.

Autologous free fat graft is a widely accepted method of facial contour restoration in Parry-Romberg syndrome (PRS); however, complex and unpredictable facial anatomy can render this surgery extremely challenging. The integration of 3-dimensional (3D) technology strategies as a method to enhance surgical aesthetic outcomes has been demonstrated.A retrospective chart review was performed for PRS with autologous, free fat graft between 2016 and 2017. Based on 3D volumetric facial analysis and presurgical simulation, a 3D printed fat graft guide was produced. Surgical outcomes were analyzed by volumetric measurements of the upper, middle, and lower face segments.A total of 9 patients were included in the study. Their upper and middle facial volumes before and after the procedures showed statistically significant volume augmentation (upper face, P = 0.004; middle face, P = 0.002) 6 months postoperatively (T1). Facial asymmetry was also statistically significantly corrected (middle face P = 0.012; lower face P = 0.025) at 1 year after the procedure (T2).The advantageous application of 3D comprehensive technology for aesthetic improvements in patients with PRS with autologous, free fat graft treatment has been demonstrated. Precise preoperative planning based on simulations and postoperative 3D volumetric analyses can help adequately predict fat graft strategies.