Three-dimensional Surface Imaging Research Articles

条纹投影动态三维表面成像技术综述

The dynamic three-dimensional(3D) surface imaging technology based on fringe projection was summarized and the characteristics of typical strategies were analyzed. Firstly, the basic principle of the technique was introduced, including the basic structure of the system, the principle of 3D surface imaging, and the two typical phase extraction methods, phase shifting method and Fourier transform method. Secondly, the dynamic imaging scheme including high speed projection scheme and dynamic 3D surface imaging method using relatively low speed camera was introduced. Thirdly, the absolute phase acquisition methods in dynamic 3D image were introduced, mainly analog and digital coding and area statistical coding, were introduced. Finally, the methods of accurate dynamic phase measurement were introduced.

Algoritmos de desplazamiento de fase de siete cuadros para la perfilometría tridimensional usando proyección de franjas y cómputo suave

In this paper, we present a set of seven-frame algorithms for the phase shifthing profilometry and their application for the three-dimensional surface imaging using soft computing. This set obtained generate the most common seven-frame algorithms in the state of art. The algorithms are analized for the compensation of common errors such as phase shifthing, phase errors because variation of light or bias.

Exploring the midline soft tissue surface changes from 12 to 15 years of age in three distinct country population cohorts.

Several studies have highlighted differences in the facial features in a White European population. Genetics appear to have a major influence on normal facial variation, and environmental factors are likely to have minor influences on face shape directly or through epigenetic mechanisms. The aim of this longitudinal cohort study is to determine the rate of change in midline facial landmarks in three distinct homogenous population groups (Finnish, Latvian, and Welsh) from 12.8 to 15.3 years of age. This age range covers the pubertal growth period for the majority of boys and girls. A cohort of children aged 12 were monitored for facial growth in three countries [Finland (n = 60), Latvia (n = 107), and Wales (n = 96)]. Three-dimensional facial surface images were acquired (using either laser or photogrammetric methods) at regular intervals (6-12 months) for 4 years. Ethical approval was granted in each country. Nine midline landmarks were identified and the relative spatial positions of these surface landmarks were measured relative to the mid-endocanthion (men) over a 4-year period. This study reports the children who attended 95 per cent of all scanning sessions (Finland 48 out of 60; Latvia 104 out of 107; Wales 50 out of 96). Considerable facial variation is seen for all countries and sexes. There are clear patterns of growth that show different magnitudes at different age groups for the different country groups, sexes, and facial parameters. The greatest single yearly growth rate (5.4 mm) was seen for Welsh males for men-pogonion distance at 13.6 years of age. Males exhibit greater rates of growth compared to females. These variations in magnitude and timings are likely to be influenced by genetic ancestry as a result of population migration. The midline points are a simple and valid method to assess the relative spatial positions of facial surface landmarks. This study confirms previous reports on the subtle differences in facial shapes and sizes of male and female children in different populations and also highlights the magnitudes and timings of growth for various midline landmark distances to the men point.

Unilateral Tissue Expander/Implant Two-Stage Breast Reconstruction with the Assistance of Three-Dimensional Surface Imaging.

In China, traditional preoperative planning of unilateral breast reconstruction mainly depends on anthropometric measurement and visual assessment. Thus, the lack of objective assessment of breast volume and shape would likely result in suboptimal reconstruction outcomes. Three-dimensional surface imaging (3D-SI), which could provide objective measurement data of the breast, may be a promising solution to this problem. A retrospective review of patients undergoing tissue expander (TE)/implant breast reconstruction without any mammoplasty surgery on the contralateral sides in our hospital from August 2013 to May 2018 was performed. All the patients underwent unilateral mastectomy with immediate or delayed insertion of TE, followed by an exchange of a silicone gel implant without contralateral procedures. 3D images were obtained at the time of preoperation, the routine expansion visit, and post-exchange of implant. The breast volume measured by 3D-SI served as a guide to conduct the surgery management, such as in deciding the total volume of expansion and guiding the final implant size selection. 3D-SI also provided objective data to evaluate the final outcomes of the reconstruction. Fifty-one patients were included in this study, in which eighteen patients underwent immediate TE insertion and thirty-three patients underwent delayed TE insertion. The ptosis degree of contralateral breasts was assessed as follows: forty-four were normal, and seven showed mild ptosis. The average expansion degree was controlled at 161.6% ± 14.1% compared to the contralateral breasts. The volume of implants exchanged had a strong linear correlation with the 3D volume of the contralateral breasts at the end of expansion (P < 0.01). The mean time of follow-up was 9.1 ± 6.6months. There was only one patient who experienced TE leakage with secondary infection and received TE exchange. For the immediate reconstruction group, the overall breast symmetry improved at the completion of implant exchange (P < 0.01), with an average asymmetry of 5.3% ± 4.0% compared with 10.6% ± 6.1% initially. For the delayed reconstruction group, the reconstructed side achieved good volume symmetry to the contralateral side (P > 0.05). There was no significant difference in breast basal width between bilateral breasts post-reconstruction (P > 0.05). 3D-SI serves as a valuable adjunct by providing accurate 3D volume of breasts within TE/implant breast reconstruction in Chinese patients without obvious breast ptosis, which could facilitate surgeons to achieve good reconstructive outcomes. 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 Cross-Sectional Study to Understand 3D Facial Differences in a Population of African Americans and Caucasians.

Objective The purpose of this cross-sectional retrospective study was to use three-dimensional surface imaging to determine gender dimorphism and facial morphological changes from adolescence to adulthood in African American and Caucasian populations. Materials and Methods Three-dimensional images were captured and the total sample size included 371 subjects. Images were combined using Rapidform 2006 Plus Pack 2 software to produce a male and female facial average for each population. Comparisons were conducted within the following categories: (1) gender comparison within each race, (2) adult and adolescent comparison within each race, and (3) adult and adolescent comparison between the races. Results Adolescent gender comparisons within each race showed high percentages of similarity. However, adult females in both races showed more prominent periorbital, malar, and nasolabial regions and less prominent lower forehead, nose, and lower face compared with adult males of the same race. African American adult females showed increase in length and width of the face, increased nasal tip projection, and decreased periorbital regions compared with African American adolescent females. Welsh adult females had an increase in the nose and chin projection compared with Welsh adolescent females. Adult males of both races had increase in nose and chin projection, increase in length and width of the face, and decreased periorbital, malar, and nasolabial regions compared with adolescent males of the same race. African American adolescents had a wider alar base, more protrusive lips, and periorbital regions, and less prominent nose and chin compared with the Welsh adolescents. African American adults also had a wider alar base; more protrusive lips and periorbital regions; a broader face; and more retrusive chin, nose, nasolabial region; and lower forehead compared with Welsh adults. Conclusions Few differences were noted between genders within the same racial groups during adolescence. However, changes became more distinct in adulthood. From adolescence to adulthood, facial morphologies were similarly matched within the gender for females; however, there were significant changes for males. Lastly, facial morphology patterns tend to be established early in life.

Preoperative breast volume evaluation of one-stage immediate breast reconstruction using three-dimensional surface imaging and a printed mold.

Accurate assessment of breast volume is an essential component of preoperative planning in one-stage immediate breast reconstruction (IBR) for achieving breast symmetry and a satisfactory cosmetic outcome. In this study, we compared breast volume estimation using three-dimensional (3D) surface imaging with magnetic resonance imaging (MRI) to determine the accuracy of breast volume measurements. Further, a 3D printing mold for facilitating autologous breast reconstruction intraoperatively is described. Patients scheduled to therapeutic or prophylactic mastectomy with one-stage IBR, either by autologous tissue transfer or direct implant, from 2016 to 2019, were enrolled in this study. 3D surface image and MRI were performed to evaluate breast volume and shape. The results were validated by the water displacement volume of the mastectomy specimen. Finally, a 3D printing mold was designed for breast reconstruction with autologous tissue. Nineteen women who were scheduled to have 20 mastectomies (18 unilateral and one bilateral) were included. There was a strong linear association between breast volume measured using the two different methods and water displacement of mastectomy specimens when a Pearson correlation was used (3D surface image: r = 0.925, p < 0.001; MRI: r = 0.915, p < 0.001). Bland-Altman plots demonstrated no proportional bias between the assessment methods. The coefficient of variation was 52.7% for 3D surface imaging and 59.9% for MRI. The volume of six breasts was evaluated by both measurements and the intraclass correlation coefficient was 0.689 for 3D surface image (p = 0.043) and 0.743 for MRI (p = 0.028). Using 3D surface image to evaluate breast shape and volume is a quick, effective, and convenient method. The accuracy, reproducibility, and reliability of 3D surface imaging were comparable with MRI in our study. In addition, 3D-printed molds can achieve better symmetry and aesthetic outcomes in immediate autologous breast reconstructions.

Validation of two handheld devices against a non-portable three-dimensional surface scanner and assessment of potential use for intraoperative facial imaging

The aim of this study was to compare accuracy and timing of two handheld, mobile three-dimensional surface imaging (3DSI) devices against an established non-portable medical imaging system, and to evaluate future intraoperative use for facial surgery. Surface-to-Surface root mean square analysis was used to evaluate both a consumer device (Sense 3D) and a professional surface scanner (Artec Eva) against a reference imaging system (Vectra XT). Two assessors repeatedly 3D-imaged the facial region of an imaging phantom and 30 volunteers in two separate sessions. Using both mobile devices, intraoperative 3DSI of 10 rhinoplasty patients was compared with preoperative reference imaging. Intraclass Correlation Coefficient was calculated for repeated measurements. Artec Eva yielded mean deviations below 0.5mm for the whole face and all subunits excluding the eye region. Sense 3D showed similar deviations for the whole face, but otherwise only in the central and lateral forehead unit and the medial cheek. Variability was low for both the non-portable Vectra XT and Artec Eva, whereas full-face assessment using Sense 3D resulted in high variability. When compared to the preoperative reference images, intraoperative rhinoplasty 3DSI revealed low deviations for Artec Eva and high deviations for Sense 3D. The 3D surfaces captured by Artec Eva showed a similarly desirable accuracy for facial imaging as Vectra XT reference images. This handheld device presents a suitable option for the objective documentation during rhinoplasty surgery. Sense 3D was unable to accurately capture complex facial surfaces and is therefore limited in its usefulness for intraoperative 3DSI.

Whole-body surface assessment - implementation and experiences with 360° 3D whole-body scans: opportunities to objectively monitor the extremities and the body trunk

Three-dimensional surface imaging (3DSI) has proven to be useful in providing objective aid to the planning process and documentation of various plastic-surgical procedures. Although this technology is routinely used in the surface and volume analysis of the face and breast, it has been of limited use in registering and quantifying the resulting changes to the entire body surface. The aim of this study was the clinical implementation of 360° whole-body scans to evaluate the treatment of lipoedema. Three 3DSI devices (Eva, Thor and Sense) were tested for precision and reproducibility regarding whole-body scans. Using a standardised setup consisting of an automatic turntable and predetermined body poses, human subjects were analysed by measuring axial circumferences and quantifying defined layers of body volume. The relevant statistical and clinical deviations were subsequently evaluated. A standardised procedure for 360° scans was successfully implemented. All tested scanners yielded sufficient results with respect to intraindividual reproducibility (p > 0.05). The Eva and Thor scanners delivered comparable results for axial circumference and volume analysis (p > 0.05). The Sense scanner allowed for a precise analysis in the area of the body trunk, but had significant deficits regarding the lower extremity (p < 0.05). The data analysis was then successfully applied to selected clinical cases. A procedure to reproducibly capture and analyse the human body was successfully established for clinical use in plastic surgery. Two of the tested 3DSI devices allowed for an objective surface and volume analysis of the human body. The third scanner (Sense) offered the ability to perform 360° scans at a low cost, albeit lacking in precision when applied to certain areas of the body. These findings may help to objectively evaluate the effects of different procedures on the entirety of the body surface in the future.

The Surface-Volume Coefficient of the Superficial and Deep Facial Fat Compartments: A Cadaveric Three-Dimensional Volumetric Analysis.

Soft-tissue filler injections for the treatment of facial aging can result in different skin surface effects depending on the targeted facial fat compartment and fascial plane. This work investigates the tissue response of defined amounts of soft-tissue filler material injected into superficial and deep facial fat compartments by means of the calculation of the surface-volume coefficient. Four fresh frozen cephalic specimens obtained from human donors (three female and one male; mean age, 74.96 ± 22.6 years; mean body mass index, 21.82 ± 6.3 kg/m) were studied. The superficial and deep lateral forehead compartments, deep temporal fat pad, sub-orbicularis oculi fat compartment, and deep medial cheek fat compartment were injected with aliquots of 0.1 cc of contrast-enhanced material and scanned using three-dimensional surface imaging, resulting in a total of 226 injection and scanning procedures. The sub-orbicularis oculi fat compartment revealed the highest correlation coefficient (rp = 0.992; p < 0.001) and the highest surface-volume coefficient (0.94). The compartment with the lowest tissue response was the deep medial cheek fat compartment (rp = 0.745; p < 0.001; surface-volume coefficient = 0.29), followed by the deep lateral forehead compartment (rp = 0.814; p < 0.001; surface-volume coefficient = 0.68), superficial lateral forehead compartment (rp = 0.824; p < 0.001; surface-volume coefficient = 0.74), and deep temporal fat pad (rp = 0.947; p < 0.001; overall surface-volume coefficient = 0.64). These results, confirmatory in their nature to current injection strategies, provide evidence for the validity and reliability of the surface-volume coefficient. Injection procedures should be targeted in terms of facial fat compartments and fascial planes for a desired aesthetic outcome, as each fat compartment and fascial plane has unique tissue responses to injected soft-tissue fillers.

Uniform 3D meshes to establish normative facial averages of healthy infants during the first year of life

Three-dimensional (3D) surface imaging systems are replacing direct anthropometry as the preferred method for capturing facial soft-tissues. Aims of this study were: (1) to develop normative average 3D faces of healthy infants aged 3, 6, 9, and 12 months and (2) to describe normative average 3D facial growth data in infants aged 3 to 12 months. Three-dimensional images of 50 healthy children were acquired at 3, 6, 9, and 12 months of age using the 3dMDcranial system. Four average faces with uniform meshes (3, 6, 9, and 12 months) were developed and registered based on the children’s reference frames. Distance maps of growth of the total facial surface and of the nose, upper lip, chin, forehead and cheeks for the intervals 3 to 6 months, 6 to 9 months, and 9 to 12 months of age were calculated. Mean growth of the total facial surface was 3.9 mm (standard deviation [SD] 1.2 mm), 3.5 mm (SD 0.9 mm), and 1.6 mm (SD 0.7 mm) at 3 to 6 months, 6 to 9 months, and 9 to 12 months, respectively. Regarding the selected regions of the face, the mean growth of the nose and upper lip were the largest (3.7 mm and 3.6 mm, respectively) between 6 and 9 months of age. The mean growth of the forehead, cheeks and chin were the largest (5.4 mm, 3.2, and 4.7 mm, respectively) between 3 and 6 months of age. For all facial regions, growth clearly diminished from 9 to 12 months of age. Normative data on the growth of the full face, nose, upper lip, chin, forehead and cheeks are presented. Such data can be used in future studies to identify the effectiveness of treatment of orofacial deformities such as orofacial clefts during the first year of life.

Effect of skin tone on the accuracy of hybrid and passive stereophotogrammetry

Three-dimensional (3D) surface images acquired from stereophotogrammetry are increasingly being used to plan or evaluate treatment by plastic surgeons. Stereophotogrammetry exists in active, passive, and hybrid forms. Active and hybrid stereophotogrammetry are believed to capture darker surfaces more accurately than passive stereophotogrammetry. The purpose of this study was to investigate whether skin tone has a clinically relevant effect on the accuracy of hybrid and passive stereophotogrammetry. Seven subjects with different skin tones were recruited. 3D-printed face and breast were spray-painted in six different colors, ranging from white to black. The skin tones and paint colors were objectified by measuring their melanin index. 3D photos of the subjects and 3D prints were acquired with hybrid and passive stereophotogrammetry. These 3D photos were matched with specialized software, and their geometric differences were calculated. None of the 3D photos showed a clinically relevant mean inaccuracy. On the 3D prints, hybrid stereophotogrammetry resulted in a smaller standard deviation of the inaccuracies than passive stereophotogrammetry (0.20 ± 0.06mm vs. 0.35 ± 0.07mm, p < 0.001). Passive stereophotogrammetry yielded a correlation between the melanin index of the spray paint colors and the standard deviation of the inaccuracy (Pearson's R=0.60, p=0.04). On human subjects, no correlation or difference in standard deviation of the accuracy was found. Skin tone does not influence the accuracy of hybrid and passive 3D stereophotogrammetry in a clinically relevant way.

Micro deep learning profilometry for high-speed 3D surface imaging

How to obtain object information as rich as possible, with the highest possible speed and accuracy from recorded optical signals, has been a crucial issue to the pursuit of powerful imaging technologies. Nowadays, the speed of ultra-fast photography can exceed one quadrillion. However, it can record only two-dimensional images which lack the depth information, greatly limiting our ability to perceive and to understand the complex real-world objects. Inspired by recent successes of deep learning methods in computer vision, we present a novel high-speed three-dimensional (3D) surface imaging approach named micro deep learning profilometry (μDLP) using the structured light illumination. With a properly trained deep neural network, the phase information is predicted from a single fringe image and then can be converted into the 3D shape. Our experiments demonstrate that μDLP can faithfully retrieve the geometry of dynamic objects at 20,000 frames per second. Moreover, comparative results show that μDLP has superior performance in terms of the phase accuracy, reconstruction efficiency, and the ease of implementation over widely used Fourier-transform-based fast 3D imaging techniques, verifying that μDLP is a powerful high-speed 3D surface imaging approach.

Three-dimensional facial morphological features of young Han Chinese women: A preliminary study

Objective To explore the feasibility of our method on assessing the three-dimensional facial morphological features based on three-dimensional surface imaging techniques. Methods According to the admission criteria, three-dimensional facial images of 34 attractive young Chinese women and 172 healthy reference young women were selected from the three-dimensional facial images database of our department. For those images, anthropometric facial measurements including facial height, width, the degree of convexity and concavity were computed using three-dimensional surface imaging techniques combined with three-dimensional coordinate system. The variance between attractive group and reference group was analyzed and the facial morphological features of each group were preliminarily summarized. Results Both groups met the criteria of mesoprosopy, not the vertical facial trisection and rule of fifths . The attractive group had a relatively narrow anterior facial frame, a more rounded and full upper face compared with the reference group. They also had smaller intercanthal width compared with the reference group. Moreover, the attractive group showed more prominent nose, more full and prominent medial cheek. In addition, the attractive group shared less protruded upper lips and less retruded chin compared with the reference group. Conclusions Assessing facial morphology using three-dimensional surface imaging techniques is a convenient and feasible method. The evaluation of sagittal facial convexity and concavity is an indispensable part of facial morphology features assessment. Key words: Imaging, three-dimensional; Anthropometry; Face; Coordinate system; Sagittal position

Fluoroscopy and Dynamic Pressure-Based Foot Orthoses for Children With Flatfoot

ABSTRACT Introduction The current nonsurgical treatment for pediatric flatfoot includes shoe modification, inserts, and foot orthoses (FOs). However, these methods do not affect the course of flatfoot in children and have only limited evidence of correction of foot pronation. The goals of this study are 1) to describe how to design novel customized FOs using plantar pressure and fluoroscopic measurements; and 2) to assess kinematics and kinetics of the foot and ankle joint and functional outcomes at baseline and 12-month follow-up. Materials and Methods One child with bilateral flatfeet received trio-pressure measurements, including dynamic plantar pressure, single sensor pressures on the lateral calcaneus, and medial talar head. The two-dimensional (2D) foot motion in the sagittal plane during the stance phase using single gantry fluoroscopy was recorded. Three-dimensional (3D) surface images of the entire foot and distal lower limb were registered. Results A total of 14 pressure metrics and three-dimensional (3D) foot and ankle topography were used to design the new orthoses and generate a computer-aided design model. Data from the fluoroscopic images were used to evaluate the orthotic design. Finally, two orthoses were designed and manufactured with a rapid prototype system (SLS). Discussion The gait-based software was successfully developed to design the new orthoses. Features included use of navicular height, talar and calcaneal alignment, pressure metrics, and foot geometry. This case study had 12-month follow-up and showed that the new FOs reduced pain and improved functional outcomes. Conclusions Use of gait-based software allows a further approach directly into the rapid prototype systems for orthoses designed to address pes valgus deformity.

Tattoo free setup for partial breast irradiation: A feasibility study.

PurposePatients undergoing external beam accelerated partial breast irradiation (APBI) receive permanent tattoos to aid with daily setup alignment and verification. With the advent of three‐dimensional (3D) body surface imaging and two‐dimensional (2D) x‐ray imaging‐based matching to surgical clips, tattoos may not be necessary to ensure setup accuracy. We compared the accuracy of conventional tattoo‐based setups to a patient setup without tattoos.Materials/methodsTwenty consecutive patients receiving APBI at our institution from July 10, 2017 to February 13, 2018 were identified. All patients received tattoos per standard of care. Ten patients underwent setup using tattoos for initial positioning followed by surface imaging and 2D matching of surgical clips. The other ten patients underwent positioning using surface imaging followed by 2D matching without reference to tattoos. Overall setup time and orthogonal x‐ray‐based shifts after surface imaging per fraction were recorded. Shift data were used to calculate systematic and random error.ResultsAmong ten patients in the “no tattoo” group, the average setup time per fraction was 6.83 min vs 8.03 min in the tattoo cohort (P < 0.01). Mean 3D vector shifts for patients in the “no tattoo” group were 4.6 vs 5.9 mm in the “tattoo” cohort (P = NS). Mean systematic errors in the “no tattoo” group were: 1.2 mm (1.5 mm SD) superior/inferior, 0.5 mm (1.6 mm SD) right/left, and 2.3 mm (1.9 mm SD) anterior/posterior directions. Mean systematic errors in the “tattoo” group were: 0.8 mm (2.2 mm SD) superior/inferior, 0.3 mm (2.5 mm SD) right/left, and 1.4 mm (4.4 mm SD) anterior/posterior directions. The random errors in the “no tattoo” group ranged from 0.6 to 0.7 mm vs 1.2 to 1.7 mm in the “tattoo” group.ConclusionsUsing both surface imaging and 2D matching to surgical clips provides excellent accuracy in APBI patient alignment and setup verification with reduced setup time relative to the tattoo cohort. Skin‐based tattoos may no longer be warranted for patients receiving external beam APBI.

3D Mammometric Changes in the Treatment of Idiopathic Gynecomastia.

Three-dimensional surface imaging (3DSI) has shown promise for plastic surgeons to objectively assess changes in body contour and breast volume. To assess the surgical outcome after bilateral subcutaneous mastectomy (BSM) and water jet-assisted liposuction (WAL) as treatment for idiopathic gynecomastia, using 3DSI to document changes regarding nipple-areolar complex (NAC) and breast volume. Thirty male patients (Simon II A to B) receiving BSM and WAL were enrolled. Eight subjects received additional mastopexy and NAC reduction. Use of a Vectra 3D Imaging System® before and 6months after surgery provided data regarding changes of NAC placement and NAC and breast dimensions. The sum volume of intraoperatively approximated lipoaspirate before and after centrifugation and mastectomy specimens quantified using water displacement were compared with 3D-assessed differences in volume. When compared to the NAC dimensions defined during surgery, patients receiving NAC reductions showed nonsignificant postoperative changes in NAC dimensions. Patients without additional mastopexy showed a significant (p < 0.001) vertical (15.7 ± 14.3%) and horizontal (17.1 ± 15.0%) reduction in NAC diameter. 3D volume changes (92.8 ± 26.4mL) showed significant differences (p < 0.001) 6months after surgery compared to the intraoperatively measured lipoaspirate before (182 ± 54.5mL) and after (120 ± 34.6mL) centrifugation. Although it is clear that patient satisfaction must remain the prime focus of surgical body contouring, 3DSI has proven valuable to objectively demonstrate both the anticipated outcome and further findings regarding treatment of idiopathic gynecomastia. 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 .

Facial aesthetic fat graft retention rates after filtration, centrifugation, or sedimentation processing techniques measured using three-dimensional surface imaging devices.

Objective:How to increase the long-term retention rate of autologous fat grafting has been widely discussed. This study aimed to evaluate long-term fat graft retention rates for the most widely used fat processing methods in the area of facial esthetic surgery, including centrifugation, filtration, and sedimentation, using three-dimensional (3D) imaging.Data Sources:PubMed, Embase, Wiley/Cochrane Library, and Web of Science databases were comprehensively searched from inception to July 2018 according to the guidelines of the American Society of Plastic Surgeons Fat Graft Task Force Assessment Methodology.Study Selection:Articles were screened using predetermined inclusion and exclusion criteria. Data collected included patient characteristics, follow-up devices, fat grafting techniques, and clinical outcomes. Patient cohorts were pooled, and fat graft retention rates were calculated. Complications were summarized according to different clinical characteristics.Results:Of 77 articles, 10 clinical studies met the inclusion criteria and reported quantified measurement outcomes with 3D imaging which provide precise volumetric data with approximately 2% standard deviation compared to real volumes. Data of 515 patients were included. Fat grafting retention varied from 21% to 82%. We found filtration and centrifugation techniques could result in better retention outcomes. However, retention varied within each processing technique, with no significant difference among the 3 techniques. Twenty-two complications were reported among 515 patients, including donor-site hematoma (1 case), mild post-operative erythema (2 cases), mild volumetric asymmetries (2 cases), chronic edema (2 cases), overcorrection (2 cases), skin irregularity (6 cases), and headache or dysesthesia (7 cases).Conclusions:Filtration and centrifugation techniques may result in better fat grafting retention outcomes than gravity sedimentation; however, more accurate statistical evidence is needed. Controversies continue to exist with respect to the performance of the different fat-processing techniques in fat graft retention.

Three-Dimensional Surface Imaging in Plastic Surgery

Three-Dimensional Surface Imaging in Plastic Surgery

Homography estimation by two PClines Hough transforms and a square-radial checkerboard pattern.

The homography matrix is crucial for many optical metrology applications, such as three-dimensional surface imaging by structured-light projection. In this paper, a straightforward homography estimation method using the image of three particular points on the reference plane is proposed. For this, a new square-radial checkerboard pattern designed to generate three sets of concurrent lines is proposed. The lines and points of interest are detected using two PClines Hough transforms. Relevant concepts such as parallel coordinates and the used Hough transforms are explained. The usefulness of our proposal is verified experimentally.

Soft tissue nasal asymmetry as an indicator of orofacial cleft predisposition.

The biological relatives of offspring with nonsyndromic orofacial clefts have been shown to exhibit distinctive facial features, including excess asymmetry, which are hypothesized to indicate the presence of genetic risk factors. The significance of excess soft tissue nasal asymmetry in at-risk relatives is unclear and was examined in the present study. Our sample included 164 unaffected parents from families with a history of orofacial clefting and 243 adult controls. Geometric morphometric methods were used to analyze the coordinates of 15 nasal landmarks collected from three-dimensional facial surface images. Following generalized Procrustes analysis, Procrustes ANOVA and MANOVA tests were applied to determine the type and magnitude of nasal asymmetry present in each group. Group differences in mean nasal asymmetry were also assessed via permutation testing. We found that nasal asymmetry in both parents and controls was directional in nature, although the magnitude of the asymmetry was greater in parents. This was confirmed with permutation testing, where the mean nasal asymmetry was significantly different (p < .0001) between parents and controls. The asymmetry was greatest for midline structures and the nostrils. When subsets of parents were subsequently analyzed and compared (parents with bilateral vs. unilateral offspring; parents with left vs. right unilateral offspring), each group showed a similar pattern of asymmetry and could not be distinguished statistically. Thus, the side of the unilateral cleft (right vs. left) in offspring was not associated with the direction of the nasal asymmetry in parents.