Evolution of 3D Surface Imaging Systems in Facial Plastic Surgery

Single-camera photogrammetry using a mobile phone for low-cost documentation of corpses

Photogrammetry is a technique for studying and defining objects' shape, dimension, and position in a three-dimensional space using measurements obtained from two-dimensional photographs. It has gained popularity following the development of computer graphics technologies and has been applied to various branches of medicine. In this study, the authors present a method for low-cost photorealistic documentation of corpses during autopsy using single-camera photogrammetry with a mobile phone. Besides representing the body by demonstrating the injured and non-injured body parts as control, evidencing the body parts on a 3D reconstruction allows easy explanation to nonmedical experts such as lawyers.

Anthropometry and Current Aesthetic Concept of the Lower Third of the Face and Lips in Caucasian Adult Population: A Systematic Review and Meta-Analysis

BACKGROUND

The lack of standardization of the norms and aesthetic concept of the lower third of the face and lips creates challenges in reconstructive surgery and aesthetic procedures. A large-scale, anthropometric measurements summary poses an alternative for establishing universal patterns.

METHODS

A systematic review was conducted by searching PubMed, Embase, Google Scholar and Web of Science using keywords: lip, face, aesthetics, beauty, anthropometry and Caucasian. Seventy records were included in the review and checked in detail in terms of available data.

RESULTS

The study contains a meta-analysis of twelve parameters with sufficient quantitative data-lip width, nose width, facial width, lower third of the face height, midline mandible height, total height of the upper and lower lip, upper and lower vermilion height, cutaneous upper lip height and nasolabial and mentolabial angle.

CONCLUSIONS

The review provides a detailed database of primary anthropometric studies of lips and perioral regions of the healthy Caucasian population. The attractiveness of the region is focused on uniformity of proportions. Notably, results acquired with different methods of measurement are not interchangeable. Despite many published anthropometric studies, systems for conducting the measurements and reporting the results are not sufficiently unified to quantitatively assess meticulous key aesthetic clinical parameters.

LEVEL OF EVIDENCE I

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine Ratings, please refer to Table of Contents or online Instructions to Authors www.springer.com/00266 .

Three-Dimensional Photography for Evaluating the Effectiveness of Botulinum Toxin Injection for Masseter Hypertrophy

BACKGROUND

Masseter hypertrophy is a common condition that causes a undesirable square face, and often treated with botulinum toxin type A (BoNTA). Subjective assessments of BoNTA effectiveness vary from physician to patient, necessitating an objective approach for evaluation. This study introduces three-dimensional photography (3DP) for the first time in clinical assessment to evaluate BoNTA treatment for masseter hypertrophy.

METHODS

Ten patients received 36U of BoNTA at three injection points on each side masseter muscle. 3DP scanner using Artec Eva® was taken at the first, third, and sixth postoperative months for objective evaluation. Patient's self-perceived prominence, patients self-rated satisfaction, and physicians provided 5-grade scores were the subjective indicators.

RESULTS

A significant decrease in left masseter volume at the sixth month (P = 0.002, P = 0.004 at rest and clenching, respectively) was observed. Patient's self-perceived prominence decreased at the first (P = 0.021) and third (P = 0.039) months. Physicians' scores significantly decreased at all postoperative months. No significant changes were noted in the right masseter volume and patients self-rated satisfaction. Patient self-rated satisfaction did not consistently correlate with objective measures, except for left masseter with clenching at the sixth month.

CONCLUSION

Three-dimensional photography accurately quantifies facial changes post-BoNTA treatment. Despite objective improvements, patient satisfaction may not align consistently. Reliable assessment tools are crucial in cosmetic surgery to manage expectations and prevent disputes.

LEVEL OF EVIDENCE IV

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Frontiers in Three-Dimensional Surface Imaging Systems for 3D Face Acquisition in Craniofacial Research and Practice: An Updated Literature Review

Digitalizing all aspects of dental care is a contemporary approach to ensuring the best possible clinical outcomes. Ongoing advancements in 3D face acquisition have been driven by continuous research on craniofacial structures and treatment effects. An array of 3D surface-imaging systems are currently available for generating photorealistic 3D facial images. However, choosing a purpose-specific system is challenging for clinicians due to variations in accuracy, reliability, resolution, and portability. Therefore, this review aims to provide clinicians and researchers with an overview of currently used or potential 3D surface imaging technologies and systems for 3D face acquisition in craniofacial research and daily practice. Through a comprehensive literature search, 71 articles meeting the inclusion criteria were included in the qualitative analysis, investigating the hardware, software, and operational aspects of these systems. The review offers updated information on 3D surface imaging technologies and systems to guide clinicians in selecting an optimal 3D face acquisition system. While some of these systems have already been implemented in clinical settings, others hold promise. Furthermore, driven by technological advances, novel devices will become cost-effective and portable, and will also enable accurate quantitative assessments, rapid treatment simulations, and improved outcomes.

Three-Dimensional Analysis of Tear Trough Volume After Lower Blepharoplasty with Midface Lift

Background: This study aims to evaluate three-dimensional stereophotogrammetry measured volume changes in the tear trough area after lower blepharoplasty with midface lift with or without orbital fat manipulation. Objective: Among patients undergoing midface lift surgery, volume change by three-dimensional photography in the tear trough region was compared between those having no orbital fat manipulation, fat transposition, or fat resection. Methods: This is a prospective study of 260 eyelids of 130 patients who underwent cosmetic midface surgery. All patients had an external skin muscle flap midface lift. During the procedure, medial inferior orbital fat was resected, repositioned to a preperiosteal dissection pocket, or not manipulated. Forty-six patients (35.4%) had no fat manipulation, 42 patients (32.3%) had fat preservation with repositioning to the preperiosteal pockets on the medial inferior orbital rim, and 42 patients (32.3%) had fat resection without repositioning. Results: All patients had volume gain in tear trough volume. The amount was not statistically significantly different between fat treatment groups. Mean follow-up time was 12 months (range 6-20 months). Conclusions: Midface lifting improved tear trough volume irrespective of how fat was manipulated.

Virtual Surgical Planning and Three-Dimensional Printing in Rhinoplasty

Recent developments in three-dimensional (3D) imaging technology offer a more comprehensive means of assessing facial features. 3D printing allows for the transition of planning from simply a preoperative tool to an intraoperative device with the use of tools such as 3D-printed cutting guides, marking guides, or positioning guides. With the advent of 3D printing technology, 3D surface images can now be used to generate new medical models, devices, or tools to assist with rhinoplasty during preoperative, intraoperative, and postoperative phases. In the field of rhinoplasty, 3D printing can be applied in three main areas: (1) reference models, (2) surgical guides, and (3) nasal splints. The value of 3D imaging extends far beyond the benefits of "conversion" during a preoperative consultation and has the potential to greatly enhance the overall treatment of rhinoplasty patients with enhanced communication and personalized devices that can be used during surgery and in the postoperative phase.

Three-dimensional assessment of facial asymmetry in Class III subjects. Part 1: a retrospective study evaluating postsurgical outcomes

OBJECTIVE

The present study aimed to determine the site and severity of maxillomandibular asymmetry before and after orthognathic surgery in asymmetric patients.

MATERIALS AND METHODS

Presurgery and postsurgery cone beam computed tomography (CBCT) data of 21 facial asymmetry patients (7 males and 14 females, mean age: 23.0 ± 3.36 years) with soft tissue chin deviation ≥ 3 mm who had undergone bimaxillary surgery were evaluated. Seven midline and twenty bilateral hard tissue landmarks were identified for the evaluation of facial asymmetry and outcomes were assessed against age- and gender-matched control subjects.

RESULTS

In the asymmetry group, bilateral landmarks exhibited significant deviation in the mandible and midface regions. Before surgery, asymmetry was more severe at the mandibular midline and sites close to it, in the asymmetry group. Bimaxillary surgery proved to be highly effective, with a significant correction of the menton to a clinically normal value (2.90 mm, p < 0.001). After surgery, significant residual asymmetry was observed at the mental foramen (p = 0.001) in the R-L direction. Moreover, significant asymmetry persisted at the sigmoid notch (p = 0.001) in the S-I direction.

CONCLUSIONS

Mandibular midline landmarks and chin peripheral regions contribute significantly to overall facial asymmetry characteristics. Despite significant correction after bimaxillary surgery, asymmetry persisted at several sites, thereby requiring secondary correction. Comprehensive 3D presurgical planning is central for asymmetry correction in a single surgery.

CLINICAL RELEVANCE

The present study specifies the location of residual asymmetry sites and advocates the correction of those sites during initial surgery.

Photography and Photodocumentation for the Rhinoplasty Patient

Photodocumentation is an essential part of a rhinoplasty surgeon's practice. Preoperative photographs are an indispensable device for patient counseling and surgical planning. Comparison of preoperative and postoperative photographs allow for outcome evaluation, which has a variety of applications-clinical, research, teaching, medicolegal. The ever-evolving technology of photography may seem daunting, but developing a basic understanding of this tool is imperative for a successful rhinoplasty practice. This article reviews the basic photographic principles, equipment, and techniques that are essential to produce high-quality and standardized patient photographs.

Can a spontaneous smile invalidate facial identification by photo-anthropometry?

Purpose

Using images in the facial image comparison process poses a challenge for forensic experts due to limitations such as the presence of facial expressions. The aims of this study were to analyze how morphometric changes in the face during a spontaneous smile influence the facial image comparison process and to evaluate the reproducibility of measurements obtained by digital stereophotogrammetry in these situations.

Materials and Methods

Three examiners used digital stereophotogrammetry to obtain 3-dimensional images of the faces of 10 female participants (aged between 23 and 45 years). Photographs of the participants' faces were captured with their faces at rest (group 1) and with a spontaneous smile (group 2), resulting in a total of 60 3-dimensional images. The digital stereophotogrammetry device obtained the images with a 3.5-ms capture time, which prevented undesirable movements of the participants. Linear measurements between facial landmarks were made, in units of millimeters, and the data were subjected to multivariate and univariate statistical analyses using Pirouette® version 4.5 (InfoMetrix Inc., Woodinville, WA, USA) and Microsoft Excel® (Microsoft Corp., Redmond, WA, USA), respectively.

Results

The measurements that most strongly influenced the separation of the groups were related to the labial/buccal region. In general, the data showed low standard deviations, which differed by less than 10% from the measured mean values, demonstrating that the digital stereophotogrammetry technique was reproducible.

Conclusion

The impact of spontaneous smiles on the facial image comparison process should be considered, and digital stereophotogrammetry provided good reproducibility.

Three-Dimensional Analysis of Soft and Hard Tissue Changes following Orthognathic Surgery

Change in soft tissue in relation to that in hard tissue following orthognathic surgery was evaluated. Twenty-five patients were enrolled in the study. The diagnosis in all was jaw deformity (maxillary retrusion and mandibular protrusion) and all underwent a Le Fort I osteotomy and bilateral sagittal splitting ramus osteotomy. Three-dimensional (3D) computer-aided design (CAD) models (polygon models) of the hard and soft tissue of the maxilla and mandible were constructed and superimposed. Reference points were established on the pre- and postoperative hard and soft tissues. Specific elements of each reference point were divided into X, Y, and Z components, respectively, and the distances in each direction and 3D distance (normal distance) measured. The Wilcoxon signed-rank test was used to determine differences in the mean values for the distance moved of each element as the error between pre- and postoperatively. The results revealed statistically significant differences in the Y-direction in the maxilla and the X- and Z-directions in the mandible. A significant difference was also observed in the 3D distances of the maxilla and mandible. Little evidence was found of linearity between the amount of hard and soft tissue movement in the X- and Z-directions in the maxilla. This means that 3D movement in the maxilla was masked more by changes in the morphology of the soft tissue than in the mandible, making it less evident. The results of this study suggest that the 3D analysis method used enables changes in hard and soft tissues to be understood qualitatively, and that it can be used in diagnosis and treatment in orthognathic surgery. It may also be useful in simulation of morphological change in soft tissue.

Reliability of Stereophotogrammetry for Area Measurement in the Periocular Region

Three-dimensional (3D) stereophotography area measurements are essential for describing morphology in the periocular region. However, its reliability has not yet been sufficiently validated. The objective of this study was to evaluate the reliability of 3D stereophotogrammetric area measurements in the periocular region. Forty healthy volunteers had five flat paper objects placed at each of the seven periocular positions including the endocanthion and the upper medial, upper middle, upper lateral, lower medial, lower middle, and the lower lateral eyelid. Two series of photographic images were captured twice by the same investigator. Each image of the first series was measured twice by the same rater, while images of both series were measured once by a second rater. Differences between these measurements were calculated, and the intrarater, interrater, and intramethod reliability was evaluated for intraclass correlation coefficients (ICCs), mean absolute differences (MADs), technical errors of measurements (TEMs), relative errors of measurements (REMs), and relative TEM (rTEM). Our results showed that 21.2% of all ICCs were considered as excellent, 45.5% were good, 27.3% were moderate, and 6.1% were poor. The interrater ICC for the endocanthion location was 0.4% on a low level. MAD values for all objects were less than 0.3 mm², all TEM were less than 1 mm², the REM and rTEM were less than 2% for all objects, showing high reliability. 3D stereophotogrammetry is a highly reliable system for periocular area measurements and may be used in the clinical routine for planning oculoplastic surgeries and for evaluating changes in periocular morphology.

Level of Evidence IV This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.

A Prospective Randomized Study of Lateral Brow-Eyelid Complex Volume after Internal Browpexy Using Three-Dimensional Stereophotogrammetry

Background: A full lateral brow-eyelid complex may help rejuvenate and feminize the face. Objectives: To compare periorbital volume change of patients as measured by three-dimensional (3D) stereophotogrammetry before and after blepharoplasty with or without internal browpexy sutures. Methods: This is a prospective randomized controlled study of 124 eyelids of 62 adult female patients who underwent cosmetic upper eyelid blepharoplasty by a single surgeon. Subjects were randomized to blepharoplasty alone (control) or blepharoplasty with an adjunctive "brassiere suture" internal browpexy (intervention). An observer masked to the intervention measured the brow-eyelid volume using standardized images obtained with a 3D camera, before and after surgery. The minimum follow-up was 6 months postoperatively. Results: Sixty eyelids (30 patients) were treated with upper blepharoplasty alone and 64 eyelids (32 patients) had blepharoplasty plus internal browpexy. The mean volume gain was 0.85 mL in the internal browpexy intervention group and 0.19 mL in the control group. The volume increased in all patients receiving browpexy and this change was greater than after blepharoplasty alone (p < 0.05). The mean follow-up time was 16.8 months (range 6-24 months). Conclusions: Adjunctive internal browpexy during blepharoplasty was associated with increased volume of the lateral brow-eyelid complex.

Three-dimensional evaluation of soft-tissue response to osseous movement after orthognathic surgery in patients with facial asymmetry: A systematic review

To systematically assess the current literature on soft-tissue response associated with osseous movement following orthognathic surgery in patients with facial asymmetry. Six electronic databases (PubMed, EMBASE (via Ovid), Medline (via Ovid), Cochrane Library, Scopus, and Web of Science) and gray literature were searched for studies evaluating hard- and soft-tissue responses three-dimensionally after orthognathic surgery, using MeSH terms and keywords. The methodological quality and level of evidence of the included studies were analyzed using EPHPP and GRADE, respectively. The primary search yielded 125 articles, and 10 articles that satisfied the predefined inclusion criteria were finally included. All the included articles evaluated soft-tissue response, with six of them additionally investigating the magnitude of this response. Soft tissues move with hard tissues horizontally and anteroposteriorly; however, soft-tissue movement is less than hard tissue movement. In addition, soft tissue movement is more pronounced in the lower central facial region. Six articles were judged as having 'strong' methodological quality, while the evidence was found to be of 'low' quality for the soft-tissue response and the magnitude of this response. Despite a low level of evidence, the review substantiates a favorable three-dimensional soft-tissue response following osseous surgery. The soft-tissue response is more pronounced horizontally, anteroposteriorly, and in the lower central facial region. Nevertheless, well-designed prospective studies with a higher level of evidence are needed.

Virtual facial simulation of prosthetic outcome for static computer-aided implant surgery and CAD-CAM prostheses

This clinical report describes a digital process of using a 3-dimensional (3D) virtual patient at an exaggerated smile view for the pre-treatment simulation of the prosthetic outcome. In addition, the virtual patient can be used to assist with the formulation of a prosthetically - driven surgical plan for static computer-aided implant surgery (s-CAIS) and the design of the computer-aided design and computer-aided manufacturing (CAD-CAM) prostheses.

Three-Dimensional Facial Scanning at the Fingertips of Patients and Surgeons: Accuracy and Precision Testing of iPhone X Three-Dimensional Scanner

BACKGROUND

The iPhone X (Apple, Inc., Cupertino, Calif.) is the first smartphone to be released with a high-fidelity three-dimensional scanner. At present, half of all U.S. smartphone users use an iPhone. Recent data suggest that the majority of these 230 million individuals will upgrade to the iPhone X within 2 years. This represents a profound expansion in access to three-dimensional scanning technology, not only for plastic surgeons but for their patients as well. The purpose of this study was to compare the iPhone X scanner against a popular, portable three-dimensional camera used in plastic surgery (Canfield Vectra H1; Canfield Scientific, Inc., Parsippany, N.J.).

METHODS

Sixteen human subjects underwent three-dimensional facial capture with the iPhone X and Canfield Vectra H1. Results were compared using color map analysis and surface distances between key anatomical landmarks. To assess repeatability and precision of the iPhone X three-dimensional scanner, six facial scans of a single participant were obtained and compared using color map analysis. In addition, three-dimensionally-printed facial masks (n = 3) were captured with each device and compared.

RESULTS

For the experiments, average root mean square was 0.44 mm following color map analysis and 0.46 mm for surface distance between anatomical landmarks. For repeatability and precision testing, average root mean square difference following color map analysis was 0.35 mm. For the three-dimensionally-printed facial mask comparison, average root mean square difference was 0.28 mm.

CONCLUSIONS

The iPhone X offers three-dimensional scanning that is accurate and precise to within 0.5 mm when compared to a commonly used, validated, and expensive three-dimensional camera. This represents a significant reduction in the barrier to access to three-dimensional scanning technology for both patients and surgeons.

Accuracy of Portable Face-Scanning Devices for Obtaining Three-Dimensional Face Models: A Systematic Review and Meta-Analysis

The use of three-dimensional face-scanning systems to obtain facial models is of increasing interest, however, systematic assessments of the reliability of portable face-scan devices have not been widely conducted. Therefore, a systematic review and meta-analysis were performed considering the accuracy of facial models obtained by portable face-scanners in comparison with that of those obtained by stationary face-scanning systems. A systematic literature search was conducted in electronic databases following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines for articles published from 1 January 2009 to 18 March 2020. A total of 2806 articles were identified, with 21 articles available for the narrative review and nine studies available for meta-analysis. The meta-analysis revealed that the accuracy of the digital face models generated by the portable scanners was not significantly different from that of the stationary face-scanning systems (standard mean difference (95% confidence interval) = -0.325 mm (-1.186 to 0.536); z = -0.74; p = 0.459). Within the comparison of the portable systems, no statistically significant difference was found concerning the accuracy of the facial models among scanning methods (p = 0.063). Overall, portable face-scan devices can be considered reliable for obtaining facial models. However, caution is needed when applying face-scanners with respect to scanning device settings, control of involuntary facial movements, landmark and facial region identifications, and scanning protocols.

Facial Reconstruction: A Systematic Review of Current Image Acquisition and Processing Techniques

Introduction: Plastic and reconstructive surgery is based on a culmination of technological advances, diverse techniques, creative adaptations and strategic planning. 3D imaging is a modality that encompasses several of these criteria while encouraging the others. Imaging techniques used in facial imaging come in many different modalities and sub-modalities which is imperative for such a complex area of the body; there is a clear clinical need for hyper-specialized practice. However, with this complexity comes variability and thus there will always be an element of bias in the choices made for imaging techniques. Aims and Objectives: The aim of this review is to systematically analyse the imaging techniques used in facial reconstruction and produce a comprehensive summary and comparison of imaging techniques currently available, including both traditional and novel methods. Methods: The systematic search was performed on EMBASE, PubMed, Scopus, Web of Science and Cochrane reviews using keywords such as "image technique/acquisition/processing," "3-Dimensional," "Facial," and "Reconstruction." The PRISMA guidelines were used to carry out the systematic review. Studies were then subsequently collected and collated; followed by a screening and exclusion process with a final full-text review for further clarification in regard to the selection criteria. A risk of bias assessment was also carried out on each study systematically using the respective tool in relation to the study in question. Results: From the initial 6,147 studies, 75 were deemed to fulfill all selection criteria and selected for meta-analysis. The majority of papers involved the use of computer tomography, though the use of magnetic resonance and handheld scanners using sonography have become more common in the field. The studies ranged in patient population, clinical indication. Seminal papers were highlighted within the group of papers for further analysis. Conclusions: There are clearly many factors that affect the choice of image acquisition techniques and their potential at being ideal for a given role. Ultimately the surgical team's choice will guide much of the decision, but it is crucial to be aware of not just the diagnostic ability of such modalities, but their treatment possibilities as well.

New Horizons in Imaging and Diagnosis in Rhinoplasty

Three-dimensional (3D) surface imaging has found its place in aesthetic surgery globally. The first attempt to use 3D surface imaging technique in clinic was in 1944 by Thalmaan, who used stereo photogrammetry to examine an adult with facial asymmetry and a baby with Pierre Robin syndrome. Three-dimensional photography is becoming more common allowing for a more dynamic facial evaluation, although it is associated with increased cost.

Reliability of the Linear Measurement (Contact) Method Compared with Stereophotogrammetry (Optical Scanning) for the Evaluation of Edema after Surgically Assisted Rapid Maxillary Expansion

Many techniques have been developed to evaluate facial swelling after maxillofacial surgeries. Patients who undergo surgically assisted rapid maxillary expansion (SARME) develop facial edema more often than those who undergo minor oral surgeries. Reliable systems to assess soft tissue dimensions offer many advantages for documentation and treatment planning across surgical fields. (1) Background: The objective assessment of facial swelling is advantageous as it allows the evaluation of the effect of anti-inflammatory drugs. Therefore, this study aimed to compare the reliabilities of linear measurement method and optical scanning for the objective assessment of facial swelling after SARME. (2) Methods: Sixteen (12 women and 4 men) patients were enrolled. Linear measurements between guide points and facial scans were obtained for the left and right sides preoperatively and 1, 2, and 5 days after SARME. Preoperative values were subtracted from each post-operative value and the differences were compared between the two measurement methods. (3) Results: There were no statistically significant differences between the right and left sides at any time point in the measurements with either method. (4) Conclusions: Recently, stereophotogrammetry has been considered the first choice method for evaluating facial swelling. Furthermore, we found a strong correlation between volumetric analysis and linear measurement at all time points and for both sides.

Two-dimensional versus three-dimensional Frӓnkel Manoeuvre: a reproducibility study

Background/Objectives

To assess intra- and inter-observer reproducibility of the evaluation of the Frӓnkel Manoeuvre (FM) on three-dimensional (3D) scans and to compare it to the assessment on two-dimensional (2D) pictures.

Materials/Methods

This study included 44 individuals with a skeletal Class II malocclusion [9–16-years old mean age ± standard deviation: 13.5 ± 2.01 years]. All patients had a full Class II molar relationship, overjet ≥6 mm and point A, Nasion, point B angle (ANB) ≥5 degrees. During the FM, each patient was invited to bite in centric occlusion and then to posture the mandible forward to reach a Class I molar relationship. The FM was recorded both by a normal camera and a 3D scanner (3dMD system). Six examiners divided into two groups according to their orthodontic clinical experience (&lt;5 and &gt;10 years), and one gold standard in the evaluation of FM, commented twice (every 15 days) on both 2D photographs (T0 and T2) and 3D scans (T1 and T3). The intra-observer agreement and the inter-observer agreement compared to the gold standard were evaluated by computing the Cohen’s K.

Results

The agreement between observations for each examiner ranged from 0.36 to 1 on 2D pictures (T0 versus T2), and from 0.22 to 0.69 on 3D scans (T1 versus T3). The overall agreement was 0.63 (95 per cent CI = 0.35–0.91) in 2D analysis and 0.5 (95 per cent CI = 0.35–0.64) in 3D analysis.

Conclusions/Implications

The FM was less reproducible when performed on 3D records than on 2D pictures.

Three-dimensional photographic analysis of the face in European adults from southern Spain with normal occlusion: reference anthropometric measurements

Background

Recent non-invasive 3D photography method has been applied to facial analysis, offering numerous advantages in orthodontic. The purpose of this study was to analyze the faces of a sample of healthy European adults from southern Spain with normal occlusion in order to establish reference facial soft tissue anthropometric parameters in this specific geographic-ethnic population, as well as to analyze sexual dimorphism.

Methods

A sample of 100 healthy adult volunteers consisting of 50 women (mean age, 22.92 ± 1.56 years) and 50 men (mean age, 22.37 ± 2.12 years) were enrolled in this study. All participants had normal occlusion, skeletal Class I, mesofacial pattern, and healthy body mass index. Three-dimensional photographs of the faces were captured non-invasively using Planmeca ProMax 3D ProFace^®. Thirty landmarks related to the face, eyes, nose, and orolabial and chin areas were identified.

Results

Male displayed higher values in all vertical and transversal dimensions, with the exception of the lower lip height. Larger differences between sexes were observed in face, mandible, and nose. Male also had higher values in the angular measurements which referred to the nose. No sex differences were found in transverse upper lip prominence or transverse mandibular prominence. No differences were found in the ratio measurements, with the exception of intercantal width/nasal width, which was higher in women than in men.

Conclusions

Reference anthropometric measurements of facial soft tissues have been established in European adults from southern Spain with normal occlusion. Significant sexual dimorphism was found, with remarkable differences in size between sexes

Electronic supplementary material

The online version of this article (10.1186/s12903-019-0898-y) contains supplementary material, which is available to authorized users.

Artificial intelligence, regenerative surgery, robotics? What is realistic for the future of surgery?

The potential of surgery lies in the technological advances that would complement it. The landscape of the field will differ depending on the time period being looked at and would no doubt include conjecture. Initial breakthroughs will need to pave the way for future medical technology and apply to the surgical sciences. Within the next 10 years we would expect to see the emergence of big data analysis, cuttingedge image processing techniques for surgical planning and better implementation of virtual and augmented reality in operating theatres for both patient care and teaching purposes. Over the next 50 to 100 years, the use of quantum computing should lead to increased automation in our healthcare systems. The inception of novel biomaterial invention and advanced genetic engineering will usher in the new age of regenerative medicine in the clinical setting. The future of surgery includes many predictions and promises, but it is apparent that the development will lead to bettering outcome and focus on patient care.

Adaptive GLOH with PSO-trained NN for the recognition of plastic surgery faces and their types

Numerous algorithms have met complexity in recognizing the face, which is invariant to plastic surgery, owing to the texture variations in the skin. Though plastic surgery serves to be a challenging issue in the domain of face recognition, the concerned theme has to be restudied for its hypothetical and experimental perspectives. In this paper, Adaptive Gradient Location and Orientation Histogram (AGLOH)-based feature extraction is proposed to accomplish effective plastic surgery face recognition. The proposed features are extracted from the granular space of the faces. Additionally, the variants of the local binary pattern are also extracted to accompany the AGLOH features. Subsequently, the feature dimensionality is reduced using principal component analysis (PCA) to train the artificial neural network. The paper trains the neural network using particle swarm optimization, despite utilizing the traditional learning algorithms. The experimentation involved 452 plastic surgery faces from blepharoplasty, brow lift, liposhaving, malar augmentation, mentoplasty, otoplasty, rhinoplasty, rhytidectomy and skin peeling. Finally, the proposed AGLOH proves its performance dominance.

Three-dimensional Morphing and Its Added Value in the Rhinoplasty Consult

Background:

The evolving literature on 3D surface imaging demonstrates that this technology is becoming the preferred simulation technique in hospitals and research centers. However, no study has demonstrated before the superiority of this facility over standard 2D simulation during preoperative evaluation in rhinoplasty.

Methods:

One hundred seventy-two consecutive patients requesting rhinoplasty were included. Patients answered a questionnaire following a 2D simulation and subsequently experienced 3D morphing. A single question was answered regarding the added value of the latter by patients and surgeons, respectively.

Results:

In our survey, satisfaction with 2D morphing reached 61%. Ninety-five percentage of the same group considered 3D simulation an added value over 2D. Additionally, 84% of patients requesting revision rhinoplasty admitted that 3D computer simulation has helped them understand the aims of surgery, in contrast to 61% of patients from the primary group. Furthermore, patients unsatisfied with their 2D simulation got reassured following 3D simulation to undergo surgery at a higher percentage (67%), compared with the group initially satisfied with 2D (48%). Women appeared reassured by 3D imaging in higher percentage (63%) compared with men (42%). The 2 surgeons, however, found 3D simulations to be an added value in 66% and 74% of all patients.

Conclusions:

The overwhelming majority of our patients considered 3D simulation an added value over 2D. Patients initially unsatisfied with 2D morphing, revision rhinoplasty patients, and women seemed to be the groups that appreciated more 3D than 2D computer simulation. In contrast, surgeons considered the facility of 3D an added value in two-thirds of the patients.

Anthropometric Evaluation of Periorbital Region and Facial Projection Using Three-Dimensional Photogrammetry

INTRODUCTION

Direct anthropometric and three-dimensional (3D) photogrammetry measurements have been used extensively in cleft/craniofacial surgery to assess morphological changes and surgical outcomes. Craniofacial procedures alter the sagittal projection of periorbital bony prominences. Mulliken described a method of measuring their projection relative to the corneal plane but is impractical in clinical practice. Three-dimensional photogrammetry may offer a solution; however, the cornea is not visualized on this. The authors propose to develop new normative measurements of facial projection relative to the pupil.

METHODS

Five 3D photographs were taken of 5 individuals using Vectra M5 camera. Facial projection measurements were taken of the sagittal projection of the bilateral periorbital landmarks and nasal radix relative to the pupil using Mirror 3D analysis. Standard deviations (SD) were determined for each subject and laterality. Chi-square tests confirmed all SD <1 mm. Intra and inter-rater reliability were confirmed with an intraclass correlation coefficient assessment.

RESULTS

Three male and 2 female subjects were photographed with 5 unique images. Standard deviations of repeat measures of all landmarks were <0.5 mm. Chi-square tests confirmed with statistical significance that SD for all values except for the radix was <1 mm (P<0.05). Intrarater reliability was high for all landmarks (intraclass correlation coefficient coefficients 0.93-0.99). Inter-rater reliability was good for the lateral canthi and excellent for all others.

CONCLUSION

This technique demonstrates repeatability with high reliability on serial photographs and is applicable to measuring surgery effects and growth on facial projection. Establishment of age-specific normative values for landmark projection will refine usage applicability in operative planning.

Facial Soft-tissue Mobility: Baseline Dynamics of Patients with Unilateral Facial Paralysis

Background:

The aims of this observational study were 2-fold: (1) To demonstrate a method and measures to quantify impaired facial soft-tissue movements in patients with facial paralysis; and (2) To quantify the differences in magnitude and velocity of facial soft-tissue movements between patients with facial paralysis and control participants.

Methods:

The study sample that addressed both aims consisted of 20 adults with acute, unilateral, flaccid facial paralysis who presented at the onset of their paralysis, and a control group of 20 healthy adults. Dynamic 3D facial movement data were collected from each participant during 11 facial animations. To compare the movements between the patients and control participants, dynamic modeling comparisons of mean facial movements were computed as well as plots of movement vectors for each animation, in addition, measures of maximum displacement, movement velocity, and asymmetry were computed.

Results:

Dynamic 3D modeling of critical facial landmarks provided precise profiles of zone-specific asymmetries and customized reporting that highlighted areas of importance for individual patients. The dynamic 3D movement data confirmed that the nonparalyzed side of patients’ faces had abnormal directional movements. As expected, the controls had significantly higher excursive facial movements during all animations except during gentle eye closure, which was greater for the patients and the controls had significantly greater movement velocity than the patients. The patients had significantly greater asymmetry for all the animations, and the hierarchy of the asymmetry was such that maximum smile > lip purse > grimace > cheek puff.

Conclusion:

Dynamic 3D modeling appeared to be an effective tool to provide precise profiles of zone-specific asymmetries and customized reports for patients with facial paralysis.

Improvement of Aesthetic and Nasal Airway in Patients With Cleft Lip Nasal Deformities: Rhinoplasty With Septal Cartilage Graft and Septoplasty

OBJECTIVE

To assess the improvement of nasal morphologies and ventilation after septal cartilage graft and septoplasty of patients with unilateral cleft lip and palate (UCLP).

DESIGN

Retrospective case-control study.

SETTING

Tertiary stomatology hospital.

PATIENTS

In total, 118 patients with UCLP who had been diagnosed with a secondary nasal deformity and had reconstructive rhinoplasty and/or septoplasty between 2010 and 2015.

MAIN OUTCOME MEASURES

Nasal Obstruction Symptoms Evaluation (NOSE) questionnaire, septum deviated angle, rhinoplasty satisfaction questionnaire, and 3-dimensional photographs.

RESULTS

Average follow-up period was approximately 12 months for both groups. NOSE and 3-dimensional computed tomography (3DCT) analysis demonstrated postoperative improvement in nasal airway function of those patients who underwent rhinoplasty and septoplasty simultaneously ( P < .05). Subjective assessment by patients' visual analog scale (VAS) and objective assessment by 3-dimensional stereophotography demonstrated postoperative improvement in nasal morphologies, particularly the columella deviation angle and nasal depth (representing nasal tip height), which are crucial parameters of nasal aesthetics ( P < .05).

CONCLUSIONS

In patients who underwent simultaneous rhinoplasty and septoplasty, nasal symmetry and ventilation function were significantly improved compared to the control group. Septum grafts could provide nasal tip support for patients with cleft lip. Three-dimensional stereophotogrammetry helped us to better visualize the surgical results. Although the septal cartilage of Asian patients is sometimes insufficient for simultaneous use for multiple grafts, septum grafts in rhinoplasty of patients with cleft lip nasal deformities could give support for nasal tips.

Validation of the Vectra H1 portable three-dimensional photogrammetry system for facial imaging

Three-dimensional (3D) surface imaging using stereophotogrammetry has become increasingly popular in clinical settings, offering advantages for surgical planning and outcome evaluation. The handheld Vectra H1 is a low-cost, highly portable system that offers several advantages over larger stationary cameras, but independent technical validation is currently lacking. In this study, 3D facial images of 26 adult participants were captured with the Vectra H1 system and the previously validated 3dMDface system. Using error magnitude statistics, 136 linear distances were compared between cameras. In addition, 3D facial surfaces from each system were registered, heat maps generated, and global root mean square (RMS) error calculated. The 136 distances were highly comparable across the two cameras, with an average technical error of measurement (TEM) value of 0.84mm (range 0.19-1.54mm). The average RMS value of the 26 surface-to-surface comparisons was 0.43mm (range 0.33-0.59mm). In each case, the vast majority of the facial surface differences were within a ±1mm threshold. Areas exceeding ±1mm were generally limited to facial regions containing hair or subject to facial microexpressions. These results indicate that 3D facial surface images acquired with the Vectra H1 system are sufficiently accurate for most clinical applications.

Pursuing Mirror Image Reconstruction in Unilateral Microtia: Customizing Auricular Framework by Application of Three-Dimensional Imaging and Three-Dimensional Printing

BACKGROUND

Advances in three-dimensional imaging and three-dimensional printing technology have expanded the frontier of presurgical design for microtia reconstruction from two-dimensional curved lines to three-dimensional perspectives. This study presents an algorithm for combining three-dimensional surface imaging, computer-assisted design, and three-dimensional printing to create patient-specific auricular frameworks in unilateral microtia reconstruction.

METHODS

Between January of 2015 and January of 2016, six patients with unilateral microtia were enrolled. The average age of the patients was 7.6 years. A three-dimensional image of the patient's head was captured by 3dMDcranial, and virtual sculpture carried out using Geomagic Freeform software and a Touch X Haptic device for fabrication of the auricular template. Each template was tailored according to the patient's unique auricular morphology. The final construct was mirrored onto the defective side and printed out with biocompatible acrylic material.

RESULTS

During the surgery, the prefabricated customized template served as a three-dimensional guide for surgical simulation and sculpture of the MEDPOR framework. Average follow-up was 10.3 months. Symmetric and good aesthetic results with regard to auricular shape, projection, and orientation were obtained. One case with severe implant exposure was salvaged with free temporoparietal fascia transfer and skin grafting.

CONCLUSIONS

The combination of three-dimensional imaging and manufacturing technology with the malleability of MEDPOR has surpassed existing limitations resulting from the use of autologous materials and the ambiguity of two-dimensional planning. This approach allows surgeons to customize the auricular framework in a highly precise and sophisticated manner, taking a big step closer to the goal of mirror-image reconstruction for unilateral microtia patients.

CLINCIAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, IV.

Validation of a new three-dimensional imaging system using comparative craniofacial anthropometry

Background

The aim of this study is to validate a new three-dimensional craniofacial stereophotogrammetry imaging system (3dMDface) through comparison with manual facial surface anthropometry. The null hypothesis was that there is no difference between craniofacial measurements using anthropometry vs. the 3dMDface system.

Methods

Facial images using the new 3dMDface system were taken from six randomly selected subjects, sitting in natural head position, on six separate occasions each 1 week apart, repeated twice at each sitting. Exclusion criteria were excess facial hair, facial piercings and undergoing current dentofacial treatment. 3dMDvultus software allowed facial landmarks to be marked and measurements recorded. The same measurements were taken using manual anthropometry, using soluble eyeliner to pinpoint landmarks, and sliding and spreading callipers and measuring tape to measure distances. The setting for the investigation was a dental teaching hospital and regional (secondary and tertiary care) cleft centre. The main outcome measure was comparison of the craniofacial measurements using the two aforementioned techniques.

Results

The results showed good agreement between craniofacial measurements using the 3dMDface system compared with manual anthropometry. For all measurements, except chin height and labial fissure width, there was a greater variability with the manual method compared to 3D assessment. Overall, there was a significantly greater variability in manual compared with 3D assessments (p < 0.02).

Conclusions

The 3dMDface system is validated for craniofacial measurements.

Use of Computer Imaging in Rhinoplasty: A Survey of the Practices of Facial Plastic Surgeons

OBJECTIVE

The objective of this study was to quantify the use of computer imaging by facial plastic surgeons.

METHODS

AAFPRS Facial plastic surgeons were surveyed about their use of computer imaging during rhinoplasty consultations. The survey collected information about surgeon demographics, practice settings, practice patterns, and rates of computer imaging (CI) for primary and revision rhinoplasty. For those surgeons who used CI, additional information was also collected, which included who performed the imaging and whether the patient was given the morphed images after the consultation.

RESULTS

A total of 238 out of 1200 (19.8%) facial plastic surgeons responded to the survey. Out of those who responded, 195 surgeons (83%) were board certified by the American Board of Facial Plastic and Reconstructive Surgeons (ABFPRS). The majority of respondents (150 surgeons, 63%) used CI during rhinoplasty consultation. Of the surgeons who use CI, 92% performed the image morphing themselves. Approximately two-thirds of surgeons who use CI gave their patient a printout of the morphed images after the consultation.

CONCLUSIONS

Computer imaging (CI) is a frequently utilized tool for facial plastic surgeons during cosmetic consultations with patients. Based on these results of this study, it can be suggested that the majority of facial plastic surgeons who use CI do so for both primary and revision rhinoplasty. As more sophisticated systems become available, it is possible that utilization of CI modalities will increase. This provides the surgeon with further tools to use at his or her disposal during discussion of aesthetic surgery.

LEVEL OF EVIDENCE V

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Can We Determine Sasang Constitutional Body Type Merely by Facial Inspection?

OBJECTIVES

This study aimed to assess the inter-observer concordance rate of anthroscopic examination on facial features among experts in Sasang constitutional medicine (SCM) in order to evaluate the presence of statistical differences in facial structural characteristics among different body types of Sasang constitution (SC), and to develop an objective method for facial analysis for diagnosing SC types to prevent SCM experts from misdiagnosis by their perceptional errors about faces.

METHODS

This was a double-blinded cross-sectional study conducted on 174 people's faces. Ten SCM experts participated in this study. Frontal and lateral photographs of subjects were standardized and displayed to 10 SCM experts for diagnosing the SC type by anthroscopic examination alone (experiment 1). The subjects' faces were analyzed by photogrammetric method to investigate the presence of any typical structural characteristics of the faces to differentiate SC type (experiment 2). Comparing subjects' SC type with anthroscopic diagnosis by 10 SCM experts, the inter-observer concordance rates were measured (experiment 1). Using photogrammetric facial analysis, a multinomial logistic model was made for analyzing the correlation of SC type and subjects' facial structural configuration (experiment 2).

RESULTS

The inter-observer concordance rate of anthroscopic examination was 2.9% in experiment 1. Using a multinomial logistic fitting model, the predicted probability for determining SC type was 52.8-57.6% in experiment 2 (p < 0.05). Prototype composite faces were also created from photographs of subjects who received the same SC type from the SCM experts.

CONCLUSIONS

As SC type cannot be precisely diagnosed using anthroscopic examination alone, SCM needs a definitive objective and scientific diagnosing method to be a scientifically verified alternative medicine and be globalized in future.

Breast volumetric analysis for aesthetic planning in breast reconstruction: a literature review of techniques

BACKGROUND

Accurate volumetric analysis is an essential component of preoperative planning in both reconstructive and aesthetic breast procedures towards achieving symmetrization and patient-satisfactory outcome. Numerous comparative studies and reviews of individual techniques have been reported. However, a unifying review of all techniques comparing their accuracy, reliability, and practicality has been lacking.

METHODS

A review of the published English literature dating from 1950 to 2015 using databases, such as PubMed, Medline, Web of Science, and EMBASE, was undertaken.

RESULTS

Since Bouman's first description of water displacement method, a range of volumetric assessment techniques have been described: thermoplastic casting, direct anthropomorphic measurement, two-dimensional (2D) imaging, and computed tomography (CT)/magnetic resonance imaging (MRI) scans. However, most have been unreliable, difficult to execute and demonstrate limited practicability. Introduction of 3D surface imaging has revolutionized the field due to its ease of use, fast speed, accuracy, and reliability. However, its widespread use has been limited by its high cost and lack of high level of evidence. Recent developments have unveiled the first web-based 3D surface imaging program, 4D imaging, and 3D printing.

CONCLUSIONS

Despite its importance, an accurate, reliable, and simple breast volumetric analysis tool has been elusive until the introduction of 3D surface imaging technology. However, its high cost has limited its wide usage. Novel adjunct technologies, such as web-based 3D surface imaging program, 4D imaging, and 3D printing, appear promising.

Application of a Novel Semi-Automatic Technique for Determining the Bilateral Symmetry Plane of the Facial Skeleton of Normal Adult Males

The accurate assessment of symmetry in the craniofacial skeleton is important for cosmetic and reconstructive craniofacial surgery. Although there have been several published attempts to develop an accurate system for determining the correct plane of symmetry, all are inaccurate and time consuming. Here, the authors applied a novel semi-automatic method for the calculation of craniofacial symmetry, based on principal component analysis and iterative corrective point computation, to a large sample of normal adult male facial computerized tomography scans obtained clinically (n = 32). The authors hypothesized that this method would generate planes of symmetry that would result in less error when one side of the face was compared to the other than a symmetry plane generated using a plane defined by cephalometric landmarks. When a three-dimensional model of one side of the face was reflected across the semi-automatic plane of symmetry there was less error than when reflected across the cephalometric plane. The semi-automatic plane was also more accurate when the locations of bilateral cephalometric landmarks (eg, frontozygomatic sutures) were compared across the face. The authors conclude that this method allows for accurate and fast measurements of craniofacial symmetry. This has important implications for studying the development of the facial skeleton, and clinical application for reconstruction.

Single-channel stereoscopic video imaging modality based on transparent rotating deflector

In this study, we developed a single-channel stereoscopic video imaging modality based on a transparent rotating deflector (TRD). Sequential two-dimensional (2D) left and right images were obtained through the TRD synchronized with a camera, and the components of the imaging modality were controlled by a microcontroller unit. The imaging modality was characterized by evaluating the stereoscopic video image generation, rotation of the TRD, heat generation by the stepping motor, and image quality and its stability in terms of the structural similarity index. The degree of depth perception was estimated and subjective analysis was performed to evaluate the depth perception improvement. The results show that the single-channel stereoscopic video imaging modality may: 1) overcome some limitations of conventional stereoscopic video imaging modalities; 2) be a potential economical compact stereoscopic imaging modality if the system components can be miniaturized; 3) be easily integrated into current 2D optical imaging modalities to produce a stereoscopic image; and 4) be applied to various medical and industrial fields.

The face of sleepiness: improvement in appearance after treatment of sleep apnea

STUDY OBJECTIVES

Anecdote but no formal evidence suggests that facial appearance improves after hypersomnolent patients with obstructive sleep apnea are treated. We investigated whether masked volunteer raters can identify post- rather than pre-treatment images as looking more alert, and whether impressions are predicted by any objective changes on highly precise 3-dimensional digital photogrammetry.

METHODS

Participants included 20 adults with obstructive sleep apnea on polysomnography and excessive sleepiness on Epworth Sleepiness Scales. Photogrammetry was performed before and after ≥ 2 months of adherent use of positive airway pressure. Twenty-two raters then assessed pre- and post-treatment facial images, paired side-by-side in random order.

RESULTS

Subjects included 14 men and 6 women, with mean age 45 ± 11 (SD) years and mean baseline apnea/hypopnea index of 26 ± 21. The 22 raters twice as often identified post-treatment rather than pre-treatment images to look more alert (p = 0.0053), more youthful (p = 0.026), more attractive (p = 0.0068), and more likely to reflect the treated state (p = 0.015). Photogrammetry documented post-treatment decreases in forehead surface volume and decreased infraorbital and cheek redness, but no narrowing of the interpalpebral fissure. Decreased deep NREM sleep at baseline, and pre- to post-treatment decrements in facial redness showed promise as predictors of improved subjective ratings for alertness.

CONCLUSIONS

Patients with obstructive sleep apnea are perceived to appear more alert, more youthful, and more attractive after adherent use of positive airway pressure. Objective changes in facial surface volume and color were identified. Post-treatment decrements in redness may inform subjective impressions of improved alertness.

Comparison of three-dimensional surface-imaging systems

BACKGROUND

In recent decades, three-dimensional (3D) surface-imaging technologies have gained popularity worldwide, but because most published articles that mention them are technical, clinicians often have difficulties gaining a proper understanding of them. This article aims to provide the reader with relevant information on 3D surface-imaging systems. In it, we compare the most recent technologies to reveal their differences.

METHODS

We have accessed five international companies with the latest technologies in 3D surface-imaging systems: 3dMD, Axisthree, Canfield, Crisalix and Dimensional Imaging (Di3D; in alphabetical order). We evaluated their technical equipment, independent validation studies and corporate backgrounds.

RESULTS

The fastest capturing devices are the 3dMD and Di3D systems, capable of capturing images within 1.5 and 1 ms, respectively. All companies provide software for tissue modifications. Additionally, 3dMD, Canfield and Di3D can fuse computed tomography (CT)/cone-beam computed tomography (CBCT) images into their 3D surface-imaging data. 3dMD and Di3D provide 4D capture systems, which allow capturing the movement of a 3D surface over time. Crisalix greatly differs from the other four systems as it is purely web based and realised via cloud computing.

CONCLUSION

3D surface-imaging systems are becoming important in today's plastic surgical set-ups, taking surgeons to a new level of communication with patients, surgical planning and outcome evaluation. Technologies used in 3D surface-imaging systems and their intended field of application vary within the companies evaluated. Potential users should define their requirements and assignment of 3D surface-imaging systems in their clinical as research environment before making the final decision for purchase.