A Double-Blind, Randomized Clinical Trial to Determine Effects of Increasing Doses and Dose-Response Relationship of IncobotulinumtoxinA in the Treatment of Glabellar Rhytids.

BACKGROUND: IncobotulinumtoxinA is an effective neuromodulator for treating glabellar rhytids. The relationship between dose and reduction in rhytid severity is well established. However, the effects of escalating doses on the treatment duration response are less understood. OBJECTIVES: The aim of this study was to assess the effects of increasing doses of incobotulinumtoxinA on the treatment duration for glabellar rhytids. METHODS: A randomized, double-blind, Phase IV study was conducted at a fully accredited, outpatient surgical facility. Subjects (31 female, 7 male) with moderate to severe glabellar rhytids were randomized to 1 of 3 incobotulinumtoxinA dose groups: 20, 60, or 100 U. Effect duration was determined by calculating the time to return to baseline for dynamic glabellar lines during maximal contraction. Follow-up was completed through 1 year, and adverse events were monitored. RESULTS: The median duration of effect was 120 days (95% confidence interval [CI] [90, 180 days]), 180 days (95% CI [180, 210 days]), and 270 days (95% CI [240, 330 days]) for the 20-, 60-, and 100-U groups, respectively. A Wald chi-square test from the Cox regression on the primary efficacy variable indicated a statistically significant effect of dose group on time to baseline (chi square = 54.63; df = 2; P < 0.001). Hazard ratios were HR = 0.21 (95% CI [0.10; 0.43] for the 60-U vs the 20-U group, and HR = 0.06 (95% CI [0.10; 0.43]) for the 100-U vs the 20-U group, indicating a statistically longer return to baseline for both the 60- and 100-U cohorts. CONCLUSIONS: There is a dose-dependent relationship between incobotulinumtoxinA and duration of effect in the glabella.

The biophysical effects of localized electrochemical therapy on porcine skin.

BACKGROUND: Minimally-invasive methods to treat scars address a common pathway of altering collagen structure, leading to collagen remodeling. OBJECTIVE: In this study, we employed in situ redox chemistry to create focal pH gradients in skin, altering dermal collagen, in a process we refer to as electrochemical therapy (ECT). The effects of ECT to induce biochemical and structural changes in ex vivo porcine skin were examined. METHODS: During ECT, two platinum electrodes were inserted into fresh porcine skin, and following saline injection, an electrical potential was applied. pH mapping, high frequency ultrasonography, and two photon excitation microscopy and second harmonic generation (SHG) microscopy were used to evaluate treatment effects. Findings were correlated with histology. RESULTS: Following ECT, pH mapping depicted acid and base production at anode and cathode sites respectively, with increasing voltage and application time. Gas formation during ECT was observed with ultrasonography. Anode sites showed significant loss of SHG signal, while cathode sites showed disorganized collagen structure with fewer fibrils emitting an attainable signal. Histologically, collagen denaturation at both sites was confirmed. CONCLUSION: We demonstrated the production of in situ acid and base in skin occurring via ECT. The effects chemically and precisely alter collagen structure through denaturation, giving insight on the potential of ECT as a simple, low-cost, and minimally-invasive means to remodel skin and treat scars.

Functional Outcomes, Quantitative Morphometry, and Aesthetic Analysis of Articulated Alar Rim Grafts in Septorhinoplasty.

IMPORTANCE: The design, use, and indications for the articulated alar rim graft (AARG) and the functional and aesthetic improvements that can be achieved have not been fully characterized. OBJECTIVE: To analyze the functional and aesthetic outcomes of AARG placement on nasal airway function, nasal base shape change, and appearance. DESIGN, SETTING, AND PARTICIPANTS: A case series study of patients who underwent septorhinoplasty with placement of AARG at University of California, Irvine Medical Center, from 2015 to 2018 was carried out. Surgical data recorded included stage of rhinoplasty (primary vs revision), use of spreader grafts, rim grafts (and dimensions), caudal septal extension graft (CSEG), lateral crural tensioning (LCT), and turbinate reductions. MAIN OUTCOMES AND MEASURES: Preoperative and postoperative Nasal Obstruction Symptom Evaluation Survey (NOSE) surveys were analyzed and correlated with AARG geometry, use of CSEG, and the LCT maneuver. Preoperative and postoperative alar base views were evaluated by fitting base shape to a parametric numerical model to categorize each to 1 of 6 shape categories. Blinded reviewers rated alar furrow severity and the alar ridge presence using a Likert scale for both preoperative and postoperative images to subjectively gauge aesthetic outcomes. RESULTS: Overall, 90 patients with both preoperative and postoperative NOSE scores who underwent septorhinoplasty and placement of an AARG were included. Of the 90 patients, 60 were women (mean age, 38.2 years). Patient NOSE scores (70.4 preoperatively to 25.1 postoperatively) significantly improved from preoperation to postoperation (P < .001), regardless of AARG size, CSEG, or LCT. Alar base shape parametric analysis showed preoperative to postoperative improvements were significant for anterior-to-posterior ratio mass distribution (95% CI, -0.16 to 0.02; P = .05) and vertical projection-to-horizontal base width ratio (95% CI, 0.01-0.32; P = .02) in flat noses and cloverleafing for narrow noses (95% CI, -0.05 to -0.01; P = .001); enhancement approached significance for reduction in lateral scalloping in cloverleaf noses (P = .06). Aesthetic analysis showed that there was a statistically significant improvement for the alar furrow (95% CI, -0.68 to -0.29 for rater 1; -0.54 to -0.27 for rater 2; and -0.59 to -0.27 for rater 3; P < .001) for all raters and for the alar ridge (95% CI, 0.16-0.48; P < .001) for 1 rater. CONCLUSIONS AND RELEVANCE: To our knowledge, this is the first study to demonstrate that AARG use is associated with statistically significant improvement in NOSE scores. Placement of AARGs may improve posterior mass ratios in flat noses and lateral cloverleafing in narrow noses as suggested by quantitative shape change parameter analysis. The placement of AARGs was associated with aesthetic and functional enhancement in the cloverleaf deformity, which is associated with a prominent alar furrow, and often external nasal valve collapse. Patient selection is key when placing AARGs. LEVEL OF EVIDENCE: NA.

Categorization and Analysis of Nasal Base Shapes Using a Parametric Model.

IMPORTANCE: Nasal base view is important for rhinoplasty analysis. Although some descriptors of nasal base shape exist, they are largely subjective and qualitative. OBJECTIVE: To evaluate a parametric model of nasal base shape and compare it with categorization by surgeons to create an objective classification system for clinical evaluation and communication. DESIGN, SETTING, AND PARTICIPANTS: Retrospective cohort review of deidentified photographs of 420 patients evaluated for possible facial plastic surgery at a tertiary care academic medical center between January 2013 and June 2017. The nasal bases were classified into 6 shape categories (equilateral, boxy, cloverleaf, flat, round, and narrow) via visual inspection. The contour of each nasal base was traced using MATLAB software (MathWorks Inc). The software then performed a curve fit to the parametric model with output of values for 5 parameters: projection-to-width ratio, the anterior-posterior positioning of the tip bulk, symmetry, degree of lateral recurvature of the nasal base, and size. The differences among shape categories for each parameter were analyzed using 1-way analysis of variance. Pairwise comparisons were then performed to ascertain how the various shapes differed. Finally, a multinomial logistic regression model was used to predict nasal base shape using parameter values. Data were analyzed between April 2017 and January 2018. MAIN OUTCOMES AND MEASURES: An algorithm that categorized nasal base shapes into 6 categories. RESULTS: The 420 nasal base photographs of patients evaluated for possible plastic surgery were categorized into 1 of 6 categories; 305 photographs were readily classified, and the remaining 115 were termed unclassified and were categorized. For both the classified and unclassified nasal base groups, there were statistically significant differences between projection-to-width ratio (classified, F5,299 = 21.51; unclassified, F4,100 = 10.59; P < .001), the anterior-posterior positioning of the tip bulk (classified, F5,299 = 3.76; P = .003; unclassified, F4,110 = 4.54; P = .002), and degree of lateral recurvature of the nasal base (classified, F5,299 = 24.14; unclassified, F4,100 = 7.21; P < .001). A multinomial logistic regression model categorization was concordant with surgeon categorization in 201 of 305 (65.9%) cases of classified nasal bases and 38 of 115 (33.0%) unclassified nasal bases. CONCLUSIONS AND RELEVANCE: The parametric model may provide an objective and numerical approach to analyzing nasal base shape. LEVEL OF EVIDENCE: NA.

Autologous Fat Harvest and Preparation for Optimal Predictable Outcomes.

Best practices in fat transfer to the face focus on tissue harvest and processing techniques. This article discusses the role of adipose-derived mesenchymal stem cells (MSCs) in mitigating tissue loss in grafting. Discrepancies among common practice and recent study results have propagated uncertainty with long-term results. Fortunately, recent increases in the understanding of these MSCs are leading providers to identify statistically more favorable tissue donor sites, harvest technique, and preparation methods to increase their concentration in transferred tissue. Future studies are needed to support or confound the long-term effects of MSC transfer on facial fat grafting.

Solid Variant of Aneurysmal Bone Cyst of the Temporal Bone.

OBJECTIVES: Aneurysmal bone cysts (ABC) are benign, rapidly growing osteolytic lesions. Solid variant of ABC (SVABC) is a rare subtype of ABC that has not been reported in the temporal bone. METHODS: We report the case of a 6-year-old boy presenting with a slowly enlarging bony protuberance over the right zygomatic/malar eminence region. Computed tomography and magnetic resonance imaging demonstrated a 2.6 × 5.8 × 5.1 cm temporal bone mass involving the right mastoid, petrous, and temporal squamosal calvarium, with extradural intracranial extension to the middle cranial fossa. RESULTS: The patient underwent preoperative embolization of feeder arteries followed by combined neurosurgical and neurotologic resection. Histopathology revealed characteristic ABC features with interspersed areas of intralesional osteoid formation. CONCLUSION: Solid variant of ABCs are rare lesions of the skull base that present a diagnostic challenge given their unique radiographic and histologic features. Thorough cytogenetic evaluation is warranted to rule out potential malignant secondary causes. Early surgical resection is essential due to the risk of intracranial extension. This is the first report of ABC of any type with concurrent involvement of the squamous, mastoid, and petrous portions of the temporal bone and the first report of SVABC of the temporal bone.

Quantitative Analysis and Classification of the Nasal Base Using a Parametric Model.

IMPORTANCE: The nasal base view is often overlooked in rhinoplasty analysis and, unlike lateral and frontal views, lacks detailed quantitative analysis and descriptors. While shape-category analysis of the nasal base is well established, these descriptive methods remain subjective and do not facilitate quantitative analysis. OBJECTIVE: To establish a simple and quantitative classification scheme using a multiple-parameter numerical model for analyzing and describing the shape of the nasal base. DESIGN, SETTING, AND PARTICIPANTS: Deidentified photographs of the nasal base view were analyzed without knowledge of patients' pathology or medical history. Each nose was classified into 1 of 6 categories derived from literature (equilateral, narrow, flat, cloverleaf, boxy, and round). Finite parametric modeling was performed on each nose, and the correlations between the resulting parameters and the 6 categories were analyzed. Photographs for this study were acquired from the practice of a single facial plastic surgeon (B.J.F.W.) at a tertiary care academic medical center. One hundred twenty-one consecutive patients who had nasal base view photographs taken were included in the study. MAIN OUTCOMES AND MEASURES: All of the 121 images were classified into 1 of the 6 categories by 1 reviewer (C.H.B.). The contour of each nasal base was curve fit to a 5-parameter numerical model. The 5 parameters controlled base size, deviation from the midline, projection-to-width ratio, degree of nasal alar recurvature, and anterior-posterior positioning of nasal base bulk. A numerical value for each nasal base shape type was predicted by the parametric model. RESULTS: In 121 patient photographs, the parametric model generated shapes that accurately matched the tracing of the actual nasal base contours with an average correlation coefficient of greater than 0.98. This finding indicates close approximation of the nasal base shape with the curve fit constructed by the PM. Parameters b (projection-to-width ratio) and e (roundedness) were shown to have significant differences among the groups (F statistic, 8.88; P < .001 and F statistic, 13.05; P < .001, respectively). These two curve-fit parameters alone could be used to classify nasal shape into 1 of the 6 clinically determined base geometries. CONCLUSIONS AND RELEVANCE: A numerical approach to classify nasal base shape was developed using a 5-parameter model and tested against subjective analysis. This model may aid in the advancement of algorithm-driven objective nasal analysis techniques, preoperative modeling, intraoperative guidance, and surgical outcome measures beyond using Likert scales. LEVEL OF EVIDENCE: NA.