Non‐surgical rhinoplasty using polydioxanone threads

To demonstrate the effects of PDO threads non‐surgical rhinoplasty on patients' quality of life (using FACE‐Q Scale) and first impression assessments.


| INTRODUC TI ON 1.| Background
Cosmetic augmentation of the nose remains a highly sort after procedure.This is supported by the continued popularity of rhinoplasty and its ranking as the most frequently performed cosmetic surgical procedure in the United States. 1 Non-surgical rhinoplasty using dermal fillers has emerged as a convenient and popular alternative to surgery given the quickness of the procedure, cheaper cost, limited to no downtime and eliminated risk of general anesthesia. 2 Nonsurgical rhinoplasty also offers providers with an alternative treatment option for minor cosmetic nasal alterations so as to avoid the increased complexity and risks associated with revision surgical rhinoplasty. 3 our experience, the most common findings in patients who seek non-surgical rhinoplasty include a shallow depth of the radix, dorsal hump, under-rotation, and under-projection of the nasal tip.
Traditionally, these findings have been effectively treated non surgically with dermal filler injections, however, rare but severe complications of tissue necrosis, stroke and blindness have been reported with the use of dermal fillers. 4,5A recent study by Rivkin reported a 0.2% rate serious adverse event after dermal filler injections with the highest risk areas being the nasal tip and side walls. 6Similarly, Beleznay et al. found that the nasal region was the most injected area that resulted in vision loss. 7ven the potentially severe risks of no surgical rhinoplasty using dermal fillers, it is imperative that other less risky non-surgical options are explored.In recent times, PDO threads have gained popularity for use in facial augmentation.10] PDO thread is made of a synthetic biodegradable polymer which has been used, for many years, in surgery for wound closure and facial thread lifting. 11,12The threads are absorbed by a hydrolysis process which stimulates fibroblasts and promotes collagen formation around the thread. 11,124][15] According to Wong, the production of collagen around the threads helps to restore volume and improves skin elasticity and texture. 12PDO threads produce physical augmentation by initially providing a rigid framework 16 and subsequently causes mild local edema, lymphocytic infiltration, and fibrosis. 16,17rrently, there are three main classes of PDO threads used for facial treatments-Monofilament, Cog and screw threads. 12nofilament threads are smooth threads that act mainly to tighten the skin and provide a mild lifting effect while Cog threads (barbed threads) have barbs which hook onto the dermal tissue to provide support and mild to moderate tissue lifting. 12,180][21] Screw threads, also known as twisted threads, have one or more threads interlinked around the needle which provides good volume restoration along with mild to moderate lifting of the facial tissue. 12th demonstrated efficacy of nasal augmentation and reduced risk of intravascular injection or embolization, PDO thread is gaining popularity as an alternative to dermal filler for nasal augmentation.Kang, Moon, and Kim have demonstrated the ability to effectively lengthen, strengthen, and raise the nasal columella using PDO threads. 8In addition to its efficacy and high patient satisfaction scores, PDO threads have an acceptable low risk profile. 8,9The absorbable nature of the threads lowers the risk of long-term complication of infection and extrusion. 22,23There is some evidence that breakdown products of PDO threads are even bacteriostatic. 24e use of PDO thread for non surgical rhinoplasty is becoming more popular as patients seek quick, minimally invasive, low risk procedures with minimal downtime.As the demand for nonsurgical PDO thread rhinoplasty increases, so does the need for prospective studies to evaluate the efficacy, and safety of PDO threads for nasal contouring.There are limited published studies on the use of PDO threads for nasal contouring and most of those studies were conducted in Korea.Two recent studies have demonstrated the efficacy and safety of PDO threads when used in combination with dermal fillers or harvested fat for nasal contouring. 8,9 our knowledge, there are no published prospective study documenting the effects of PDO thread non-surgical rhinoplasty on quality of life and first impression evaluations.

| Primary assessment
To determine the effect of PDO thread injection into the nose on patients' quality of life based on the FACE-Q scales and first impression scores.

| MATERIAL S AND ME THODS
The study is a prospective cohort study of 10 adult patients who sought non-surgical rhinoplasty.The 10 patients were sequentially screened for study and those that fulfilled the inclusion and exclusion criteria, as listed in Table 1, were enrolled for the study.All patients were examined by the treating physician to ensure they had appropriate nasal structure and treatment goals were in line with the patients' aesthetic goals.Institutional Review Board was obtained for the study and all included patients gave full informed consent for their participation in the study.
During the first treatment visit, each patient completed the pre-treatment FACE-Q survey and pre-treatment photographs were taken to include the standardized rhinoplasty views (frontal, left/right three quarter and left/right lateral views).The patient was examined, and aesthetic goals were discussed.The nose was cleaned with alcohol wipes and the treatment areas were locally anesthetized with 1% lidocaine + 1:100000 epinephrine.Once optimal anesthesia was obtained, the nose was cleansed with chlorhexidine.
The appropriate size of PDO thread was then injected into the desired area using aseptic techniques.Injections were performed by the treating surgeon to achieve optimal correction result (OCR) Posttreatment visits were conducted 2 weeks after injection to determine if optimal correction was achieved.If so, pictures were taken in a similar fashion as previously described and the patients completed the posttreatment FACE-Q survey.If additional correction was needed, then treatment using PDO threads was completed at that second visit in a similar manner as described above.Patients then returned 2 weeks after their touch up treatment for a third and final visit.During the final visit, posttreatment standardized photographs were taken, and the patients completed the posttreatment FACE-Q survey.The pretreatment and posttreatment photographs were used for the first impression evaluations and objective nasal analysis.

| Face-Q
A validated FACE-Q scale 25 was utilized and all patients completed the scale during their first and final visits.The FACE-Q is a patientreported outcome instrument utilized in facial aesthetics to measure different aspects of aesthetic outcomes including quality of life outcomes. 25In this study we used the FACE-Q scale to assess each patient's appraisal of nasal appearance, psychological well-being, social function, and psychological distress. 25

| First impression surveys
The questionnaire used by the evaluators was based on a previously developed and published first-impression survey which evaluated defined categories of perception. 26,27The categories include relationship success, social skills, financial success, academic performance, dating success, occupational success, attractiveness, and athletic skills. 26,27e-treatment and posttreatment photographs were randomized and separated into two survey books.We ensured that the pretreatment and posttreatment photos each patient were in separate survey books.One hundred and forty-six independent evaluators from a local population graded each photograph on a scale of 1(least favorable) to 10 (most favorable).Each evaluator only analyzed the photos contained in one book and they were blinded TA B L E 1 Inclusion and exclusion criteria.

Inclusion criteria Exclusion criteria
Males and females of ages 18 and above.Patients who are pregnant or nursing.
Patients with diseases, injuries, wounds or disabilities of the nose, including those with autoimmune disease affecting the nose Patients that do not understand the purpose and aspects of the study or do not sign the consent or do not complete the required treatment and follow up visit as to whether the nose was treated.The demographic (ethnicity, gender, level of education and age) data of the evaluators were recorded.

| Facial analysis
The initial and final photographs were used for comparison facial analysis.We objectively measured the efficacy of the treatment which we defined as the ability of the intervention to reduce the dorsal nasal hump to 0 mm within margin of (+/− 10% of pre injection).The Δ value for dorsal hump reduction was calculated as the value in mm of dorsal hump reduction obtained posttreatment as compared to the pretreatment photos (see Figure 1).
For the patients who had treatment of the nasal tip, a subgroup analysis was performed to assess the changes in projection and rotation.The Goode ratio (ideal ratio of 0.55-0.60)was measured to assess the change in nasal projection and the nasolabial angle (normal 90-120 degrees) was measured to assess the change in tip rotation.
All measurements were performed three times and the mean of the three measurements was used.

| Safety assessment
We monitored closely for any adverse event or complication during the treatments.At each visit we assessed for and solicited information from the patients regarding any complications or adverse events.

| Analysis method
Microsoft Excel (Redmond, WA, USA) and GraphPad (San Diego, CA, USA) were used to perform statistical analyses of the study data.
Statistical analysis was performed with two-tailed unpaired t-tests to assess differences between pre-treatment and posttreatment nasal measurements and FACE-Q scores.A two-tailed p-value <0.05 was considered significant for all results.
For the first impression scores, the statistical analysis was per-

| RE SULTS
Ten patients who met study criteria were enrolled in the study and completed the treatment protocol.There were eight women and two men in the study with ages ranging from 20 to 51 years.Seven of the ten patients identified as Caucasians and the other three where from minority racial groups.The dorsum was the most treated area of the nose.An average of 13.5 threads were used to treat the dorsum and an average of three threads were used for the tip.See Table 2 for demographic and treatment information.
The Face-Q scale was completed by all patients before and after treatment.As outlined in Table 3, there was statistically significant The objective measurements were completed on images of nine treated patients.Unfortunately, the photographs of one patient were corrupted and could not be used for measurements.Although there was a trend towards reduction of the appearance of the dorsal hump, increase in the value of Goode's ratio (nasal projection) and increase nasolabial angle (tip rotation), these values (see Table 4) did not reach the level of statistical significance (p > 0.05). in the first impression questionnaire was higher than the mean pretreatment score, however, this positive change was not statistically significant.See Table 6 for details of all categories.

| DISCUSS ION
Aesthetic providers and patients both continue to seek minimally invasive, quick, cost effective and safe ways to enhance the aesthetics of the nose.5][6][7] Similar to dermal fillers, the use of PDO threads for facial augmentation and rejuvenation continue to increase in popularity and the safety of threads have been previously documented. 8,12ng, Moon and Kim have demonstrated the ability to effectively lengthen, strengthen, and raise the nasal columella using PDO threads however, they utilized dermal fillers for volumetric changes in the nose. 8While this technique increased the aesthetic results of their treated patients, the risk of dermal filler injections still remains.
Similarly, Lee and Yang found that barbed threads along with autologous fat gel graft gave the most optimal results for projection of a nasal tip and lengthening of the dorsum. 9Although, there were no reported complications from the injected autologous fat gel graft, it should be noted that similar to dermal fillers, fat injections have a ][10] Given the previously documented risks of severe complications from filler and fat injections, we believe that it imperative that the efficacy of PDO threads alone be explored.To our knowledge this is the first prospective study to determine the effect of non surgical rhinoplasty using PDO thread alone on quality of life and first impression surveys while simultaneously evaluating the efficacy of the treatment and the safety profile of PDO thread injection in the nose.
31 Based this previous finding, we used barbed PDO threads alone in the nasal tip to increase tip rotation and projection.For the dorsum we used multiple smooth threads to add volume, act as a scaffold and stimulate collagen production with a goal of reducing the appearance of the dorsal hump.We avoided using the thicker barbed threads in this area due to concern that the thread might be more visible or palpable given the thinner skin of the rhinion.
We also thought the use of thinner and smoother threads will reduce the risk of thread extrusion.Although other studies have documented minor complications (bruising, extrusion, scarring, sensation changes and infection) of PDO thread injections, 8,11,18,19 in this study we had no complications from the treatment with PDO threads confirming the positive safety profile of PDO threads when used appropriately in the nose.
From our results, we were able to demonstrate objective reduction of dorsal hump (mean change of 1.17 mm) and increase in both the nasolabial angle (mean change of 6.04 degrees) and Goode's ratio (mean change of 0.03).However, none of these changes were statistically significant.This is likely as a result of the small sample size of the study.
As with any nasal procedure, it is important to keep in mind that the anatomic structure of each individual nose will determine the efficacy of the PDO thread procedure.Noses that need significant structural changes (e.g., saddle nose) will not benefit from non surgical procedure.Also, noses with very thick skin and weak nasal framework will likely show less change than noses with thinner skin.
Appropriate patient selection is necessary when performing nonsurgical rhinoplasty.
Each patient's quality of life assessment was performed using the FACE-Q scale.We found statistically significant improvement in the four subscales of the survey.There was an increase in social function, psychological function, and satisfaction with nose and a decrease in appearance related psychological distress after the treatment.For the first impression questionnaire, attractiveness showed a statistically significant change, and several other domains trended towards a positive change.There was an increase in the overall first impression score, but the sample size was likely too small to prove statistical significance.

TA B L E 5
First impression evaluator demographics.

| Limitations
This was a prospective cohort study with a sample size of ten consecutive patients who sought non-surgical rhinoplasty and who met inclusion criteria.Given the modest sample size, this research was probably too under powered to reveal statistically significant differences in the objective measurements.Another limitation is that the study was performed at a single private facial plastic surgery practice which affects the generalizability of the study.There could also be inherent biases in the pre-and posttreatment nasal measurements as the surgeons were not blinded.
The longevity of the achieved treatment changes in this study was out of the scope of this current study.][10][11][12] A future randomized study with a larger sample size which explores the longevity of objective changes and patient reported outcomes may be able to address further questions not addressed by this current study.Bold values are the p values that showed a statistically significant change.

| CON CLUS IONS
TA B L E 6 First impression questionnaire results.
a. To determine the efficacy of PDO thread injection into the nose as defined by the reduction of the dorsal convexity to 0 mm (+/− 10% of pre injection value), and changes in tip rotation and projection.b.To evaluate the safety profile of injecting PDO thread into the nose.
as per the patient's desired cosmetic outcome.The product used was FDA cleared PDO Max® thread ranging in size from 19 gauge to 30 gauge.The 30G × 25 mm and 30G × 38 mm smooth threads were used for the dorsum while the 19G × 38 mm & 19G × 50 mm barbed threads were used for the tip.The number of threads per treatment site was determined by the treating surgeon but did not exceed a total of 15 threads per treatment area in each session.The amount, sizes and location of the threads used were recorded for each patient.
Younger than 18 years of age No previous filler injections to nose or other nasal cosmetic/surgical treatment within the preceding 12 months Previous surgery, filler injections, or other cosmetic treatments to the nose within the last 12 months Patient freely seeking non-surgical reshaping of the nasal soft tissue History of any prior nasal implants Any history of bleeding disorders (iatrogenic or otherwise).This includes current therapy with thrombolytics, anticoagulants, or inhibitors of platelet aggregation in the preceding 3 weeks.Use of aspirin, ibuprofen, St. John's Wort, or high doses of Vitamin E supplements in the last 3 weeks.known allergy or sensitivity to any component of the study ingredients.
formed using Microsoft Excel (Redmond, WA, USA) and MATLAB (Mathworks, Natick, MA, USA).Each of the eight categories and the overall first impression mean values on the questionnaire were analyzed employing unpaired two-tailed t tests to compare differences between preprocedure and postprocedure results.The subscales were rated on a scale from 1 to 10, with a higher score indicating greater agreement with a descriptive statement associated with each subscale.A two-tailed p-value <0.05 was considered significant for all results.A 95% confidence interval (CI) was completed for each category and the total score.

Figures 2 and 3
respectively show the before and after profile images of a treated patient.This patient underwent treatment to decrease the appearance of his dorsal hump and to increase rotation of his tip.There were 146 evaluators for the first impression survey.Sixtyeight percent (n = 99) of the reviewers identified as female with a mean age around 30 years.Majority (79.5%) of the evaluators had a bachelor's degree or higher.See Table 5 for the evaluator demographic data.Of the eight categories that were scored in the first F I G U R E 1 Pretreatment and posttreatment hump measurement.Red arrow shows measured dorsal hump.impression questionnaire, attractiveness was the only category with a statistically significant change (p = 0.029).The mean posttreatment score for attractiveness was higher than the mean pre-treatment score.The overall mean posttreatment score for all the categories

TA B L E 2 3
Patient demographic data and treatment data.Face-Q scale.

F I G U R E 3
Post treatment photograph.Left photo-pretreated.Right photo: posttreatment.The patient's dorsum and tip were treated.
This is the first prospective study to demonstrate the positive effects of PDO threads nasal augmentation on patient quality of life (using FACE-Q Scale) and first impression assessment.This study shows that the PDO threads alone can be used safely to achieve minor nasal changes especially in tip rotation and appearance of dorsal hump, to improve perceived attractiveness of treated patients and improve patients' quality of life.AUTH O R CONTR I B UTI O N S O.S., R.C., S.G., E.K., N.G., B.C., S.D. designed the research study.O.S., E.K., N.G., B.C., performed the research.O.S., R.C., S.G., E.K., N.G., B.C., S.D contributed essential research tools and acquisition of data.O.S., R.C., S.G., E.K., N.G., B.C., S.D analyzed and interpreted the data.O.S drafter the paper.O.S., R.C., S.G., E.K., N.G., B.C., S.D reviewed and revised the paper for important content.All authors have read and approved the final manuscript.

FACE-Q Subscale Pre treatment (mean) Post treatment (mean) p-Value
Bold values are the p values that showed a statistically significant change.
TA B L E 4 Objective measurements.