Digital surface photogrammetry for anthropometric analysis of the cleft infant face

Morphometric Assessment of Facial Morphology in Infants with Orofacial Clefts up to two Years of Age: A Three-Dimensional Cross-Sectional Study

OBJECTIVE

To assess modelled facial development of infants with unilateral cleft lip (CL) and cleft lip and palate (UCLP) compared to controls up to two years of age.

DESIGN AND PARTICIPANTS

A total of 209 facial images of children (CL: n = 37; UCLP: n = 39; controls: n = 137) were obtained in four age categories (T0 = 0.2-0.5; T1 = 0.6-1.0; T2 = 1.1-1.5; T3 = 1.6-2.0 years) and were evaluated using stereophotogrammetry and geometric morphometry. All patients underwent lip surgery before T0, patients with UCLP underwent palatoplasty (T0, T1 before palatoplasty; T2, T3 after palatoplasty).

RESULTS

In patients with CL, the forehead was significantly retracted (p ≤ 0.001), while the supraorbital and ocular regions were prominent (p ≤ 0.001). The oronasal region appeared convex (p ≤ 0.001). The lower lip and chin were non-significantly protruded. In patients with UCLP, a significantly retracted forehead and prominent supraorbital region were apparent (p ≤ 0.001). A retrusive oronasal region (p ≤ 0.001) was observed in the middle face. The chin was anteriorly protruded (p ≤ 0.01). No progression of deviations was found with increasing age. After the first year, a slight improvement in the morphological features became apparent. The shape variability of the clefts and controls overlapped, suggesting a comparable modelled facial development.

CONCLUSIONS

The facial morphology of individuals with cleft was comparable to the norm. Shape deviation was apparent in the oronasal region, forehead, and chin, which minimised with increasing age even in complete clefts.

A novel measurement system for assessing the nose in patients with cleft lip and palate (CLP)

Objective

The presented study shows a new and innovative method to determine nasal asymmetries in a simple way in patients with cleft lip and palate (CLP) in order to plan corrective surgery.

Design

86 non-syndromic patients with cleft lip and palate were divided into 2 groups: a) patients with unilateral cleft lip and palate b) patients with bilateral cleft lip and palate.

Patients

follow-up of hospital records of 86 patients aged 2-18 years.

Main outcome

Based on standardised photos of the nose from 3 different directions, the nose symmetry was assessed. A new digital measurement system was used, which is integrated into proven clinical programmes. These were compared with a control group. In addition, a mirror fog test and a standardised questionnaire were used.

Result

The overall results showed a good symmetry of the nose postoperatively, as well as a high satisfaction of the patients and their parents. Profile and angle measurements showed a better result.

Conclusio

The presented measurement system and especially the Cleft Lip Component Symmetry Index (CLCSI) allows an individual and very effective assessment of the symmetry of the nose as well as a control of the growth in patients with CLP. The method is easy to apply in daily practice, even for untrained practitioners.

Craniofacial and three-dimensional palatal analysis in cleft lip and palate patients treated in Spain

Growth alterations have been described in patients operated on for oral clefts. The purpose of this work was to analyze the craniofacial and palate morphology and dimensions of young adults operated on for oral clefts in early childhood in Spain. Eighty-three patients from eight different hospitals were divided into four groups based on their type of cleft: cleft lip (CL, n = 6), unilateral cleft lip and palate (UCLP, n = 37), bilateral cleft lip and palate (BCLP, n = 16), and cleft palate only (CPO, n = 24). A control group was formed of 71 individuals. Three-dimensional (3D) digital models were obtained from all groups with an intraoral scanner, together with cephalometries and frontal, lateral, and submental facial photographs. Measurements were obtained and analyzed statistically. Our results showed craniofacial alterations in the BCLP, UCLP, and CPO groups with an influence on the palate, maxilla, and mandible and a direct impact on facial appearance. This effect was more severe in the BCLP group. Measurements in the CL group were similar to those in the control group. Cleft characteristics and cleft type seem to be the main determining factors of long-term craniofacial growth alterations in these patients. Prospective research is needed to clearly delineate the effects of different treatments on the craniofacial appearance of adult cleft patients.

Workflow to develop 3D designed personalized neonatal CPAP masks using iPhone structured light facial scanning

Background

Continuous positive airway pressure (CPAP) is a common mode of respiratory support used in neonatal intensive care units. In preterm infants, nasal CPAP (nCPAP) therapy is often delivered via soft, biocompatible nasal mask suitable for long-term direct skin contact and held firmly against the face. Limited sizes of nCPAP mask contribute to mal-fitting related complications and adverse outcomes in this fragile population. We hypothesized that custom-fit nCPAP masks will improve the fit with less skin pressure and strap tension improving efficacy and reducing complications associated with nCPAP therapy in neonates.

Methods

After IRB approval and informed consent, we evaluated several methods to develop 3D facial models to test custom 3D nCPAP masks. These methods included camera-based photogrammetry, laser scanning and structured light scanning using a Bellus3D Face Camera Pro and iPhone X running either Bellus3D FaceApp for iPhone, or Heges application. This data was used to provide accurate 3D neonatal facial models. Using CAD software nCPAP inserts were designed to be placed between proprietary nCPAP mask and the model infant’s face. The resulted 3D designed nCPAP mask was form fitted to the model face. Subsequently, nCPAP masks were connected to a ventilator to provide CPAP and calibrated pressure sensors and co-linear tension sensors were placed to measures skin pressure and nCPAP mask strap tension.

Results

Photogrammetry and laser scanning were not suited to the neonatal face. However, structured light scanning techniques produced accurate 3D neonatal facial models. Individualized nCPAP mask inserts manufactured using 3D printed molds and silicon injection were effective at decreasing surface pressure and mask strap pressure in some cases by more than 50% compared to CPAP masks without inserts.

Conclusions

We found that readily available structured light scanning devices such as the iPhone X are a low cost, safe, rapid, and accurate tool to develop accurate models of preterm infant facial topography. Structured light scanning developed 3D nCPAP inserts applied to commercially available CPAP masks significantly reduced skin pressure and strap tension at clinically relevant CPAP pressures when utilized on model neonatal faces. This workflow maybe useful at producing individualized nCPAP masks for neonates reducing complications due to misfit.

Effects of Positioning Errors Onto the Ratio and Angle Measurements in Photographs of Patients With Unilateral Cleft Lip and Palate

BACKGROUND

Nasolabial esthetics is 1 of the most important issues in the evaluation of treatment outcomes in patients with unilateral cleft lip and palate (CLP). Frontal and basal view photographs are commonly used to evaluate nasolabial esthetics in patients with unilateral CLP. High-quality photography plays an important role in evaluating the treatment outcomes and poor quality photographs can result in errors, whereas evaluating the treatment results. Facial proportions and angles are important in the esthetic perception of the face. Hence, this study aimed to determine the effects of positioning errors on the ratio and angle measurements in photographs of patients with unilateral CLP.

METHODS

In the clinical and computer environment, a mechanism was set up to take photos at standard and at different angles. A real-size unilateral CLP silicone doll was constructed for the photographs to be taken in the clinical setting. A test-retest was performed to determine the reliability of the measured values.

RESULTS

The correlation coefficients for the first measurement and remeasurement values were statistically significant; positive and strong correlations were obtained.

CONCLUSIONS

Based on the data obtained from our study, the angle and ratio measurements obtained from the two-dimensional photographs provided reliable results.

Three-Dimensional Quantification of Facial Asymmetry in Children with Positional Cranial Deformity

BACKGROUND

The extent of facial involvement in positional plagiocephaly is only little investigated so far. Investigation methods that take into account the challenging anatomical conditions and growth of infants' faces are desirable. In this study, the authors established a new three-dimensional photogrammetry quantification method evaluating pretherapeutic and posttherapeutic facial asymmetry in positional plagiocephaly. Furthermore, a facial asymmetry index was established and evaluated.

METHODS

Three-dimensional photographs of 100 children undergoing treatment with head orthoses were analyzed by constructing a standardized interindividual coordinate system. Defining landmarks, section planes, and point coordinates with a computer-aided design software, both sides of the faces were compared. Facial asymmetry was quantified by measuring differences between left and right sides and pretherapeutic and posttherapeutic changes in each patient. The facial asymmetry index was calculated by putting the absolute differences in relation with the coordinates of the nonaffected side.

RESULTS

Present results indicate that positional plagiocephaly results in a distinct facial asymmetry (range, -3.8 to 9.6 mm) in nearly all spatial directions and facial regions. Helmet therapy led to a significant reduction (p < 0.05) of intraindividual facial asymmetry (median change in facial asymmetry index, -1.9 to 3.1 percent). However, no correlation of the Cranial Vault Asymmetry Index and facial asymmetry (Spearman rank correlation coefficient, ρ = -0.09 to 0.47) has been seen. According to these results, severe occipital deformation does not necessarily provoke distinct facial asymmetry.

CONCLUSIONS

Present three-dimensional photogrammetry method allows the longitudinal quantification of facial involvement in positional plagiocephaly. Asymmetry has been determined in all facial regions. The facial asymmetry decreased through helmet therapy but was not eliminated completely.

Accuracy of 3-dimensional stereophotogrammetry: Comparison of the 3dMD and Bellus3D facial scanning systems with one another and with direct anthropometry

INTRODUCTION

The objective of this study was to compare the accuracy of 3-dimensional (3D) digital facial photographs taken by the Bellus3D Face Camera Pro (Bellus3D) (Bellus3D Inc, Los Gatos, Calif) and the 3dMDface system (3dMD) (3dMD Inc, Atlanta, Ga) with one another and with direct anthropometry (DA).

METHODS

A mannequin head was selected as the research object. Twenty facial landmarks were labeled on the basis of the 8 interlandmark distances and 5 angles that were defined. A 150-mm digital Vernier caliper (Mitutoyo Inc, Tokyo, Japan) with an accuracy of 0.02 mm was applied to directly measure the interlandmark distances, and the angles were calculated according to the law of cosines. All the measurements were conducted 3 times by each operator under identical conditions. Then, each scanner was used to acquire 3D photographs 5 times, generating 10 digital stereophotographs. Linear distances and angles were measured on the 3D facial photographs reconstructed with open-source MeshLab software (ISTI [Italian National Research Council], Rome, Italy). Each linear distance and angle were measured 3 times by 1 operator, and 3 examiners conducted the measurements independently. To obtain the trueness, equivalence tests were applied to compare the measurements of the 2 scanners and DA. In addition, the average absolute deviations were calculated to directly compare the trueness of 3 methods (Bellus3D vs 3dMD vs DA). Finally, the intraclass correlation coefficient was used to assess the interobserver agreement and the precision of 2 scanners.

RESULTS

As for the trueness, 7 out of 8 of the linear distance measurements (N-Pn, Sn-Pog, ORE-IRE, OLE-ILE, RLC-RMC, LLC-LMC, and CR-CL) and 3 out of 5 of the angular measurements (MLA, NFA, and INI) obtained by 3dMD were equivalent to those obtained by DA. Five out of 8 measurements (N-Pn, Sn-Pog, RLC-RMC, LLC-LMC, and CR-CL) and 1 out of 5 of the angular measurements (MLA) obtained by Bellus3D were equivalent to the measurements obtained with DA. All but 3 of the measurements (ORE-IRE, NFA, and INI) obtained with Bellus3D were equivalent to 3dMD. The mean absolute difference between 3dMD and DA was 0.36 ± 0.20 mm and 0.45° ± 0.56°; the deviation between Bellus3D and DA was 0.61 ± 0.47 mm and 0.99° ± 0.61°; and the deviation between Bellus3D and 3dMD was 0.38 ± 0.37 mm and 0.62° ± 0.39°. Regarding the precision of the 2 scanners, the intraclass correlation coefficient value of 3dMD was approximately 1.00, and that of Bellus3D was 0.99. The interobserver agreement for each linear and angular measurement was 0.99.

CONCLUSIONS

The trueness of each scanner was clinically acceptable for diagnosis and treatment planning. The precision of 3D photographs obtained by 3dMD and Bellus3D showed good scanning repeatability. The interobserver agreement between the 3 operators was rated as excellent (0.99).

Superimposition of serial 3-dimensional facial photographs to assess changes over time: A systematic review

INTRODUCTION

Superimpositions of 3-dimensional photographs enable a thorough and risk-free assessment of facial changes over time. However, the available methods and the evidence supporting them have not been assessed systematically. The paper summarizes and assesses the current evidence on superimposition methods of serial 3-dimensional facial photographs available in the literature.

METHODS

The following databases were searched without time restriction (last updated December 2020): MEDLINE via PubMed, EMBASE, Cochrane Library, and Google Scholar. Unpublished literature was searched on Open Grey and Grey Literature Report. Authors were contacted if necessary, and reference lists of relevant papers were screened. All studies with sample size ≥6 that tested the accuracy or precision of a superimposition technique, or agreement between different techniques regarding facial surface changes, were considered. The 2 authors performed data extraction independently using predefined forms. The risk of bias was assessed through the Quality Assessment and Diagnostic Accuracy Tool 2 tool.

RESULTS

Eight studies fulfilled the inclusion criteria. The total risk of bias of 7 studies was high and of 1 low. Seven studies had high total applicability concerns, and 1 was unclear. There was high heterogeneity among studies, which tested constructed planes through manually selected landmarks, a configuration of 9 landmarks, various surface areas, and the entire facial surface as superimposition references. A small rectangular area on the forehead combined with one on the middle part of the nose and the lower wall of the orbital foramen showed promising results.

CONCLUSIONS

The limited available evidence suggests that surface-based registration is superior to landmark-based registration. Further research in the field is mandatory.

Craniofacial Anthropometry: Normative Data for Caucasian Infants

PURPOSE

Craniofacial anthropometry is a valuable tool for characterization of facial dysmorphology and evaluation of treatment outcomes. Databases of normal anthropometric ranges are limited for infants. The aim of this study is to establish normative data for craniofacial anthropometric measurements in Caucasian infants.

METHODS

This is a prospective cross-sectional study including Caucasian infants (≤12 months old) that were recruited from a pediatric medicine practice and Boston Children's Hospital. Infants with craniofacial deformities, trauma or operations were excluded. The sample was stratified by age (in months) into 4 groups: 0 to 3, 3.1 to 6, 6.1 to 9, and 9.1 to 12. Three dimensional (3D) photographs were obtained for all subjects. Forty-five standard anthropometric points were plotted, and 37 measurements were made on the 3D photographs. Two evaluators independently performed all measurements. One examiner repeated the measurements on 25% of the subjects. Intraclass correlation coefficients (ICC) were calculated to assess inter-rater and intra-rater agreement.

RESULTS

Thirty-three subjects were enrolled in the study. The mean age for the entire sample was 6.3 ± 3.0 months, and 17 subjects (52%) were female. The mean ages (months) for each group were: 1.9 ± 0.7 for group 1 (n = 6); 4.4 ± 0.7 for group 2 (n = 8); 7.5 ± 1.1 for group 3 (n = 11); and 9.9 ± 1.0 for group 4 (n = 8). Descriptive statistics are presented for each group. Inter- and intra-rater agreements were acceptable (ICC >0.6) for 21 anthropometric measurements.

CONCLUSIONS

This study generated normative craniofacial anthropometric measurements for Caucasian infants. These data can be used in the interpretation of measurements for research studies evaluating craniofacial anomalies in this population.

Validity and reproducibility of the 3D VECTRA photogrammetric surface imaging system for the maxillofacial anthropometric measurement on cleft patients

OBJECTIVES

To validate the accuracy and reproducibility of linear measurements of three-dimensional (3D) images and to compare the measurements with the direct anthropometry method on cleft lip and palate (CLP) patients.

MATERIALS AND METHODS

Nineteen linear facial measurements were derived from 16 standardized surface landmarks obtained from 37 cleft patients (20 males, 17 females; mean age 23.84 years, standard deviation ± 6.02). They were taken manually with calipers and were compared with the digitally calculated distance on the 3D images captured using the VECTRA-M5 360° Imaging System with pre-marked landmarks. Another pair of 19 linear measurements were computed on the 3D images 2 weeks apart for intra- and inter-observer agreements. Statistical analyses used were paired t test, the Bland-Altman analysis, and the intra-class correlation coefficient (ICC) index.

RESULTS

Most of the linear measurements showed no statistically significant differences between the proposed method and direct anthropometry linear measurements. Nevertheless, bias of the 3D imaging system is present in the linear measurements of the nose width and the upper vermillion height. The measurements' mean biases were within 2 mm, but the 95% limit of agreement was more than 2 mm. Intra- and inter-observer measurements generally showed good reproducibility. Four inter-observer measurements, the upper and lower face heights, nose width, and pronasale to left alar base were clinically significant.

CONCLUSIONS

Measurements obtained from this 3D imaging system are valid and reproducible for evaluating CLP patients.

CLINICAL RELEVANCE

The system is suitable to be used in a clinical setting for cleft patients. However, training of the operator is strictly advisable.

Efficacy of morpho-functional repair in management of different morphological variants of unilateral complete cleft lip

BACKGROUND

To study the surgical outcome in various morphological variants of unilateral complete cleft lip in our high volume centre over a period of 4 years, using Morpho-Functional technique in all cases by indirect two dimensional photographic analysis.

METHODS

In this prospective cohort study, 749 patients with Unilateral Cleft Lip with palate were included over a period of 4 years from January 2010 to December 2014. All Subjects underwent surgery before the age of 1 year with the follow-up two dimensional photographs taken at 4 years post-operatively. Eight measurements were performed on the photographs. All parameters were measured on both Cleft & Non cleft sides and the ratio was considered with the normal side as the base line. Shapiro-Wilk and Kolmogrov-Smirnoff tests were used to confirm that the data was normally distributed. One way ANOVA was done to find out if there were any significant differences amongst the different groups along various parameters, respectively. Further Tukey post hoc analysis was done to confirm where the differences occurred between groups.

RESULTS

None of the groups showed any statistical differences on any parameters. There were minor variations between the different groups due to the ranging morphology of the defect but overall satisfactory to good results were seen on all measured parameters evaluated.

CONCLUSION

This shows that the Morphofunctional technique, with its combinations & modifications of various school of thought, is versatile enough to achieve good surgical outcomes despite the wide variations seen in size and type of defects in unilateral cleft lip. This comes about because of the comprehensive nature of the technique & the balance that it creates among the affected structures.

Facial and midfacial symmetry in cleft patients: Comparison to non-cleft children and influence of the primary treatment concept

PURPOSE

Patients with cleft lip, alveolus and palate (CLAP) may suffer from marked asymmetry with an impact on attractiveness and psychosocial aspects. The aim of this study was to assess symmetry in CLAP patients compared to non-cleft controls of similar age with regard to cleft type and treatment concept.

MATERIALS AND METHODS

In CLAP patients with different cleft forms and in healthy non-cleft subjects (control group) a three-dimensional stereophotogrammetric face scan was performed and an objective 3D asymmetry index (AI) was calculated for the whole face, the midface, the upper lip and the nose.

RESULTS

In total, 305 patients were included: 140 CLAP patients (90 male, 50 female, mean age 9.9 ± 3.6 years) and 165 controls (87 male, 78 female, mean age 8.7 ± 2.1 years). In general, CLAP patients showed significantly higher asymmetry than controls, with the most severe asymmetry found in unilateral complete CLAP. Patients treated according to an actual concept considering reconstruction of all affected muscular systems had a significant lower and more favourable AI than patients not treated according to this concept (p < 0.05).

CONCLUSION

An adequate treatment concept is essential to achieve better results concerning symmetry in CLAP, but symmetry values of healthy non-cleft controls are not reached.

Longitudinal Follow-up of Individuals With Cleft Lip Using Three-Dimensional Stereophotogrammetry

The usefulness of three-dimensional (3D) stereophotogrammetry for treating cleft lip (CL) has been well documented. However, there are only a few reliable anthropometric analyses in infants with CL because at this age they cannot assume a resting facial position. Since 2014, we have used a handheld 3D imaging system in the operating room to obtain optimal images of infants with CL and palate under general anesthesia. Currently, 168 infants with a unilateral cleft, 50 infants with bilateral clefts, and 47 infants with an isolated cleft palate are being followed up in this way for a maximum of 30 months. Most patients ≥3 years of age are cooperative and allow staff to obtain 3D images without sedation. We plan to follow them until adulthood, obtaining 3D images at every intervention. Each year, >150 infants can be added to this ongoing longitudinal study. Using an archive of these digital images, various retrospective studies can be attempted in the future, which include comparisons of the long-term outcomes of various surgical techniques and interventions at different time intervals. This is the first 2-year preliminary report of a 20-year longitudinal study.

Objective measurements for grading the nasal esthetics on Basal view in individuals with secondary cleft nasal deformity

OBJECTIVE

The purpose of this study is to ascertain objective nasal measurements from the basal view that are predictive of nasal esthetics in individuals with secondary cleft nasal deformity.

DESIGN

Thirty-three patients who had undergone unilateral cleft lip repair were retrospectively reviewed in this study. The degree of nasal deformity was subjectively ranked by seven surgeons using standardized basal-view measurements. Nine physical objective parameters including angles and ratios were measured. Correlations and regressions between these objective and subjective measurements were then analyzed.

RESULTS

There was high concordance in subjective measurements by different surgeons (Kendall's harmonious coefficient = W = .825, P = .006). The strongest predictive factors for nasal aesthetics were the ratio of length of nasal alar (r = .370, P = .034) and the degree of deviation of the columnar axis (r = .451, P = .008). The columellar angle had a more powerful effect in rating nasal esthetics.

CONCLUSION

There was reliable concordance in subjective ranking of nasal esthetics by surgeons. Measurement of the columnar angle may serve as an independent, objective predictor of esthetics of the nose.

Novel computer vision analysis of nasal shape in children with unilateral cleft lip

BACKGROUND

Optimization of treatment of the unilateral cleft lip nasal deformity (uCLND) is hampered by lack of objective means to assess initial severity and changes produced by treatment and growth. The purpose of this study was to develop automated 3D image analysis specific to the uCLND; assess the correlation of these measures to esthetic appraisal; measure changes that occur with treatment and differences amongst cleft types.

METHODS

Dorsum Deviation, Tip-Alar Volume Ratio, Alar-Cheek Definition, and Columellar Angle were assessed using computer-vision techniques. Subjects included infants before and after primary cleft lip repair (N = 50) and children aged 8-10 years with previous cleft lip (N = 50). Two expert surgeons ranked subjects according to esthetic nose appearance.

RESULTS

Computer-based measurements strongly correlated with rankings of infants pre-repair (r = 0.8, 0.75, 0.41 and 0.54 for Dorsum Deviation, Tip-Alar Volume Ratio, Alar-Cheek Definition, and Columellar Angle, p < 0.01) while all measurements except Alar-Cheek Definition correlated moderately with rankings of older children post-repair (r ∼ 0.35, p < 0.01). Measurements were worse with greater severity of cleft type but improved following initial repair. Abnormal Dorsum Deviation and Columellar Angle persisted after surgery and were more severe with greater cleft type.

CONCLUSIONS

Four fully-automated measures were developed that are clinically relevant, agree with expert evaluations and can be followed through initial surgery and in older children. Computer vision analysis techniques can quantify the nasal deformity at different stages, offering efficient and standardized tools for large studies and data-driven conclusions.

Three-Dimensional Upper Lip and Nostril Sill Changes After Cleft Alveolus Reconstruction Using Autologous Bone Grafting Versus Recombinant Human Bone Morphogenetic Protein-2

Cleft alveolus in patients with unilateral complete cleft lip and palate has been alternatively reconstructed with recombinant human bone morphogenetic protein (rhBMP)-2. However, its effects on upper lip and nostril sill anatomy are not known. Thus, the objective of this investigation was to assess and compare upper lip and nostril sill changes after cleft alveolus reconstruction with autologous bone from the iliac crest region and rhBMP-2. Patients were randomly allocated into 2 groups. In group 1, autologous bone from the iliac crest region was used to fill the cleft alveolus (n = 4), and in group 2, rhBMP-2 was used to fill the cleft alveolus (n = 8). Preoperatively and at one after the surgery, computerized tomography (CT) was performed. Reformatted CT imaging was used to perform cephalometric linear measurements of the upper lip and nostril sill regions. Inter- and intragroup data of the pre and postoperative reformatted CT measurements of the upper lip and nostril sill regions did not show differences (P >0.05) in cutaneous upper lip height and projection, nostril sill elevation, and subnasale projection. There were no significant upper lip and nostril sill anatomical changes after cleft alveolus reconstruction using autologous bone grafting and rhBMP-2.

Three-Dimensional Anthropometric Database of Attractive Caucasian Women: Standards and Comparisons

The aim of this paper is to develop a database to determine a new biomorphometric standard of attractiveness. Sampling was carried out using noninvasive three-dimensional relief methods to measure the soft tissues of the face. These anthropometric measurements were analyzed to verify the existence of any canons with respect to shape, size, and measurement proportions which proved to be significant with regard to the aesthetics of the face. Finally, the anthropometric parameters obtained were compared with findings described in the international literature.

The study sample was made up competitors in the Miss Italy 2010 and 2009 beauty contest. The three-dimensional (3D) scanning of soft tissue surfaces allowed 3D digital models of the faces and the spatial 3D coordinates of 25 anthropometric landmarks to be obtained and used to calculate linear and angular measurements. A paired Student t test for the analysis of the means allowed 3 key questions in the study of biomorphometric parameters of the face to be addressed through comparison with the data available in the literature.

The question of statistical evidence for the samples analyzed being members of the populations samples reported in literature was also addressed.

The critical analysis of the data helped to identify the anthropometric measurements of the upper, middle, and lower thirds of the face, variations in which have a major influence on the attractiveness of the face. These changes involve facial width, height, and depth. Changes in measurements of length, angles, and proportions found in the sample considered were also analyzed.

Three-dimensional facial analysis of Chinese children with repaired unilateral cleft lip and palate

We analyzed the facial features of Chinese children with repaired unilateral cleft lip and palate (UCLP) and compared them with a normal control group using a three-dimensional (3D) stereophotogrammetry camera. This cross-sectional study examined 3D measurements of the facial surfaces of 20 Chinese children with repaired UCLP and 40 unaffected Chinese children aged 7 to 12 years old, which were captured using the VECTRA 3D five-pod photosystem and analyzed using Mirror software. Twenty-five variables and two ratios were compared between both groups using independent t-test. Intra- and inter-observer reliability was determined using ten randomly selected images and analyzed using intra-class correlation coefficient test (ICC). The level of significance was set at p < 0.0018. Intra- and inter-observers’ reliability was considered fair to excellent with an ICC value ranging from 0.54 to 0.99. Statistically significant differences (p < 0.0018) were found mainly in the nasolabial region. The cleft group exhibited wider alar base root width, flattened nose and broader nostril floor width on the cleft side. They tended to have shorter upper lip length and thinner upper vermillion thickness. Faces of Chinese children with repaired UCLP displayed meaningful differences when compared to the normal group especially in the nasolabial regions.

Hypertelorism and Orofacial Clefting Revisited: An Anthropometric Investigation

OBJECTIVE

Since the 1960s, multiple studies have reported a tendency toward hypertelorism in individuals with nonsyndromic orofacial clefts (OFCs). However, the association between specific cleft types and increased interorbital distance has been inconsistent. Using three-dimensional (3D) surface imaging, we tested whether different forms of clefting showed evidence of increased interorbital distance.

METHODS

Intercanthal and outercanthal distances and intercanthal indices were calculated from 3D facial surface images of 287 individuals with repaired OFCs. Raw measurements were converted to sex and age-normalized Z-scores. Mean Z-scores for individuals with cleft lip (CL), cleft lip and palate (CLP), and cleft palate (CP) were compared with reference normative values (controls) and one another directly using t tests and analysis of variance.

RESULTS

The CLP group showed a significant increase in intercanthal width (P = .001) and intercanthal index (P < .001) compared with reference norms. The CP group showed a significant decrease (P < .001) in outercanthal width. The CL group showed no difference from reference norms. The proportion of clinically hyperteloric individuals was generally low but highest in the CLP group (7.4%). Cleft severity had little effect on interorbital spacing.

CONCLUSIONS

Individuals with CLP exhibited on average a tendency toward mild hypertelorism, driven primarily by an increase in intercanthal distance. This tendency was not seen in CL or CP.

Measuring Symmetry in Children With Unrepaired Cleft Lip: Defining a Standard for the Three-Dimensional Midfacial Reference Plane

OBJECTIVE

Quantitative measures of facial form to evaluate treatment outcomes for cleft lip (CL) are currently limited. Computer-based analysis of three-dimensional (3D) images provides an opportunity for efficient and objective analysis. The purpose of this study was to define a computer-based standard of identifying the 3D midfacial reference plane of the face in children with unrepaired cleft lip for measurement of facial symmetry.

PARTICIPANTS

The 3D images of 50 subjects (35 with unilateral CL, 10 with bilateral CL, five controls) were included in this study.

INTERVENTIONS

Five methods of defining a midfacial plane were applied to each image, including two human-based (Direct Placement, Manual Landmark) and three computer-based (Mirror, Deformation, Learning) methods.

MAIN OUTCOME MEASURE

Six blinded raters (three cleft surgeons, two craniofacial pediatricians, and one craniofacial researcher) independently ranked and rated the accuracy of the defined planes.

RESULTS

Among computer-based methods, the Deformation method performed significantly better than the others. Although human-based methods performed best, there was no significant difference compared with the Deformation method. The average correlation coefficient among raters was .4; however, it was .7 and .9 when the angular difference between planes was greater than 6° and 8°, respectively.

CONCLUSIONS

Raters can agree on the 3D midfacial reference plane in children with unrepaired CL using digital surface mesh. The Deformation method performed best among computer-based methods evaluated and can be considered a useful tool to carry out automated measurements of facial symmetry in children with unrepaired cleft lip.

Measuring Symmetry in Children With Cleft Lip. Part 2: Quantification of Nasolabial Symmetry Before and After Cleft Lip Repair

OBJECTIVE

The first part of this study validated an automated computer-based method of identifying the three-dimensional midfacial plane in children with unrepaired cleft lip. The purpose of this second part is to develop computer-based methods to quantify symmetry and to determine the correlation of these measures to clinical expectations.

PARTICIPANTS

A total of 35 infants with unrepaired unilateral cleft lip and 14 infant controls.

INTERVENTIONS

Six computer-based methods of quantifying symmetry were developed and applied to the three-dimensional images of infants with unilateral cleft lip before and after cleft lip repair and to those of controls.

MAIN OUTCOME MEASURE

Symmetry scores for cleft type, changes with surgery, and individual subjects ranked according to cleft severity were assessed.

RESULTS

Significant differences in symmetry scores were found between cleft types and found before and after surgery. Symmetry scores for infants with unilateral cleft lip approached those of controls after surgery, and there was a strong correlation with ranked cleft severity.

CONCLUSIONS

Our computer-based three-dimensional analysis of nasolabial symmetry correlated with clinical expectations. Automated processing made measurement convenient. Use of these measures may help to objectively measure cleft severity and treatment outcome.

The 3D Facial Norms Database: Part 1. A Web-Based Craniofacial Anthropometric and Image Repository for the Clinical and Research Community

With the current widespread use of three-dimensional (3D) facial surface imaging in clinical and research environments, there is a growing demand for high-quality craniofacial norms based on 3D imaging technology. The principal goal of the 3D Facial Norms (3DFN) project was to create an interactive, Web-based repository of 3D facial images and measurements. Unlike other repositories, users can gain access to both summary-level statistics and individual-level data, including 3D facial landmark coordinates, 3D-derived anthropometric measurements, 3D facial surface images, and genotypes from every individual in the dataset. The 3DFN database currently consists of 2454 male and female participants ranging in age from 3 to 40 years. The subjects were recruited at four US sites and screened for a history of craniofacial conditions. The goal of this article is to introduce readers to the 3DFN repository by providing a general overview of the project, explaining the rationale behind the creation of the database, and describing the methods used to collect the data. Sex- and age-specific summary statistics (means and standard deviations) and growth curves for every anthropometric measurement in the 3DFN dataset are provided as a supplement available online. These summary statistics and growth curves can aid clinicians in the assessment of craniofacial dysmorphology.

A Pilot Study on the Influence of Facial Expression on Measurements in Three-Dimensional Digital Surfaces of the Face in Infants With Cleft Lip and Palate

OBJECTIVE

Three-dimensional surface imaging is an increasingly popular modality for face measurements in infants with cleft lip and palate. Infants are noncompliant toward producing specific facial expressions, and selecting the appropriate moment of acquisition is challenging. The objective was to estimate amount and spatial distribution of deformation of the face due to facial expression in infants with cleft lip and palate and provide recommendations for an improved acquisition protocol, including a method of quality control in terms of obtaining images with true neutral expression.

MATERIAL AND METHODS

Three-dimensional surface images of ten 4-month-old infants with unrepaired cleft lip and palate were obtained using a 3dMDface stereophotogrammetric system. For each subject, five surface images judged as representing a neutral expression were obtained during the same photo session. Mean and maximum deformations were calculated. A formalized review was performed, allowing the image exhibiting the "best" neutral expression to be selected, thus decreasing errors due to residual facial expression.

RESULTS

Deformation due to facial expression generally increased from forehead to chin. The amount of deformation in three selected regions were determined: nose (mean, 1 mm; maximum = 3 mm); cleft region (mean, 2 mm; maximum = 5 mm); chin region (mean, 5 mm; maximum = 12 mm). Analysis indicated that introduction of a formalized review of images could reduce these errors by a factor of 2.

CONCLUSIONS

The continuous change of facial expression in infants represents a substantial source of error; however, this may be reduced by incorporating a formalized review into the acquisition protocol.

3D Facial Morphometry in Children with Oral Clefts

Objectives

The aim of this study was to characterize three-dimensional (3D) facial morphological variation of children with cleft lip and palate compared to an age- and sex-matched control group.

Design

Cross-sectional, case-controlled observational morphometric study.

Materials and Methods

Subjects were 103 children aged 8 to 12 years old with cleft lip and palate—40 with unilateral cleft lip and palate, 23 with unilateral cleft lip and alveolus, 19 with bilateral cleft lip and palate, and 21 with isolated cleft palate (ICP)—and 80 sex- and age-matched control subjects. Subjects were scanned using 3D stereophotogrammetry. Thirty-nine landmarks were digitized for each scan, and the x, y, and z coordinates for each landmark were extracted. Linear and angular facial measurements were computed. Multivariate analysis of covariance was undertaken to detect significant differences in facial morphometry between the groups.

Results

Statistically significant differences ( P < .05) were observed between all groups. The greatest morphometrical impact was seen in those groups where both lip and palate were affected and repaired; the group with ICP was the most similar to the control subjects.

Conclusions

Significant differences were seen in 3D soft-tissue measurements, mainly in the nasolabial region, between the cleft groups where the lip is affected and the ICP and control groups.

Reliability of nasolabial anthropometric measures using three-dimensional stereophotogrammetry in infants with unrepaired unilateral cleft lip

BACKGROUND

Surgical and orthodontic treatment of unilateral cleft lip +/- palate can produce dramatic changes in nasolabial form; however, the lack of ideal methods with which to objectively document three-dimensional form limits the ability to assess treatment outcomes. The purpose of this study was to determine the reliability of three-dimensional stereophotogrammetry for anthropometric assessment of the unilateral cleft lip +/- palate deformity in infants before cleft lip repair.

METHODS

Preoperative three-dimensional images were acquired from 26 consecutive patients with unrepaired unilateral cleft lip +/- palate. Three raters performed indirect anthropometry on each image on two separate occasions, with at least 1 week between rating sessions. One rater performed direct measurements on participants before surgery while in the operating room. Twenty-six linear and angular measurements were considered, and intrarater, interrater, and intermethod reliability were assessed.

RESULTS

Regarding intrarater and interrater reliability, most measurements had Pearson coefficients greater than 0.75, mean differences less than 0.8 mm, and mean proportional differences less than 0.1. For measurements involving vermilion height, nostril remnants, or Cupid's bow width, Pearson coefficients ranged from 0.3 to 0.75, mean differences ranged from 0.4 to 0.9 mm, and mean proportional differences ranged from 0.1 to 0.3. Regarding intermethod reliability, correlation coefficients ranged from 0.4 to 0.75 for most measurements. The mean differences for nose and lip measurements were less than 1 mm and between 0.8 and 1.3 mm, respectively.

CONCLUSION

Three-dimensional stereophotogrammetry provides a reliable method for many anthropometric measurements of nasolabial form in infants with unrepaired unilateral cleft lip +/- palate.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Diagnostic, II.

Effect of maxillary alveolar reconstruction on nasal symmetry of cleft lip and palate patients: a study comparing iliac crest bone graft and recombinant human bone morphogenetic protein-2

BACKGROUND

Recombinant human bone morphogenetic protein (rhBMP)-2 has been used in some craniofacial centers worldwide. However, its influence on nasal morphology is unknown. Thus, the objective of this investigation was to assess the effect of maxillary alveolar reconstruction on nasal position and symmetry in unilateral complete cleft lip patients who underwent traditional iliac crest bone grafting transferring versus reconstruction using rhBMP-2.

METHODS

Nineteen unilateral complete cleft lip patients were randomly divided into two groups. In group 1, patients underwent traditional iliac crest bone grafting transferring (n = 11) and in group 2, patients underwent alveolar reconstruction using collagen matrix with lyophilized rhBMP-2 (n = 8). Computerized tomography (CT) imaging was performed preoperatively and at 6 months postoperatively using a previously standardized protocol. Linear distances using anatomic landmarks were performed using tridimensional CT data reformatted by the OsiriX(®) software. Quantitative and qualitative measurements to assess intra- and inter-group nasal position modifications were performed.

RESULTS

Intra-group pre- and postoperative comparisons showed significant differences (p < 0.05) in two linear measurements of group 1, while group 2 did not present a difference (p > 0.05). Group 2 presented significant postoperative enhancement (p < 0.05) in the quantitative nasal symmetry in one measurement. Qualitative analysis showed postoperative nasal symmetry enhancement in 75% of the measurements of group 2 and 36% of group 1. There was no statistically significant difference in the inter-group comparisons.

CONCLUSIONS

Our study demonstrated that both groups showed similar effect on nasal symmetry.

Design of aerosol face masks for children using computerized 3D face analysis

BACKGROUND

Aerosol masks were originally developed for adults and downsized for children. Overall fit to minimize dead space and a tight seal are problematic, because children's faces undergo rapid and marked topographic and internal anthropometric changes in their first few months/years of life. Facial three-dimensional (3D) anthropometric data were used to design an optimized pediatric mask.

METHODS

Children's faces (n=271, aged 1 month to 4 years) were scanned with 3D technology. Data for the distance from the bridge of the nose to the tip of the chin (H) and the width of the mouth opening (W) were used to categorize the scans into "small," "medium," and "large" "clusters."

RESULTS

"Average" masks were developed from each cluster to provide an optimal seal with minimal dead space. The resulting computerized contour, W and H, were used to develop the SootherMask® that enables children, "suckling" on their own pacifier, to keep the mask on their face, mainly by means of subatmospheric pressure. The relatively wide and flexible rim of the mask accommodates variations in facial size within and between clusters.

CONCLUSIONS

Unique pediatric face masks were developed based on anthropometric data obtained through computerized 3D face analysis. These masks follow facial contours and gently seal to the child's face, and thus may minimize aerosol leakage and dead space.

Development and reproducibility of a 3D stereophotogrammetric reference frame for facial soft tissue growth of babies and young children with and without orofacial clefts

The aim of this study was to develop a reference frame for three dimensional (3D) facial soft tissue growth analysis in children and to determine its reproducibility. Two observers twice placed the reference frame on 39 3D-stereophotogrammetry facial images of children with orofacial clefts and control children. The observers' performances were analyzed by calculating mean distance, distance variability, and P95 between the same facial surfaces at two different time points. Correlations between observers were analyzed with Pearson's correlation coefficient. The influence of presence of a cleft, absence of one ear in the photograph, and age on the reproducibility of the reference frame was checked using Student's t test. Results of intraobserver comparisons showed a mean distance of <0.40 mm, distance variability of <0.51 mm, and P95 of <0.80 mm. For interobserver reliability, the mean distance was <0.52 mm, distance variability was <0.53 mm, and P95 was <1.10 mm. Presence of a cleft, age, and absence of one ear on the 3D photograph did not have a significant influence on the reproducibility of placing the reference frame. The children's reference frame is a reproducible method to superimpose on 3D soft tissue stereophotogrammetry photographs of growing individuals with and without orofacial clefts.

Facial dimensions of Malay children with repaired unilateral cleft lip and palate: a three dimensional analysis

This comparative cross-sectional study assessed the facial surface dimensions of a group of Malay children with unilateral cleft lip and palate (UCLP) and compared them with a control group. 30 Malay children with UCLP aged 8-10 years and 30 unaffected age-matched children were voluntarily recruited from the Orthodontic Specialist Clinic in Hospital Universiti Sains Malaysia (HUSM). For the cleft group, lip and palate were repaired and assessment was performed prior to alveolar bone grafting and orthodontic treatment. The investigation was carried out using 3D digital stereophotogrammetry. 23 variables and two ratios were compared three-dimensionally between both groups. Statistically significant dimensional differences (P<0.05) were found between the UCLP Malay group and the control group mainly in the nasolabial region. These include increased alar base and alar base root width, shorter upper lip length, and increased nose base/mouth width ratio in the UCLP group. There were significant differences between the facial surface morphology of UCLP Malay children and control subjects. Particular surgical procedures performed during primary surgeries may contribute to these differences and negatively affect the surgical outcome.

Image fusion in preoperative planning

This article presents a comprehensive overview of generating a digital Patient-Specific Anatomic Reconstruction (PSAR) model of the craniofacial complex as the foundation for a more objective surgical planning platform. The technique explores fusing the patient's 3D radiograph with the corresponding high-precision 3D surface image within a biomechanical context. As taking 3D radiographs has been common practice for many years, this article describes various approaches to 3D surface imaging and the importance of achieving high-precision anatomical results to simulate surgical outcomes that can be measured and quantified. With the PSAR model readily available for facial assessment and virtual surgery, the advantages of this surgical planning technique are discussed.

Measuring progressive soft tissue change with nasoalveolar molding using a three-dimensional system

BACKGROUND

For craniofacial orthodontics and surgery to progress, accurate temporal evaluation of soft tissue and skeletal change with treatment is necessary. Evolution in three-dimensional imaging eliminates certain inherent challenges in making such measurements in infants with facial clefts.

OBJECTIVE

The aim of this pilot study was to measure progressive three-dimensional changes in nasal form in a series of infants with facial clefts during the course of presurgical nasoalveolar molding.

MATERIALS AND METHODS

In 5 infants with unrepaired cleft lip and palate, three-dimensional photographs were obtained using the 3dMD system (3dMD, Inc, Atlanta, GA) at 2-week intervals during nasoalveolar molding treatment. Using the 3dMD Vultus software, temporal soft tissue changes were evaluated quantitatively based on three-dimensional linear measurements of 3 landmarks in the nasal area and qualitative changes in the surface shell.

RESULTS

Increase in columellar length on the cleft side and decrease of the nostril floor on the noncleft side were observed in all subjects. Progressive changes were observed most significantly in week 4 (T3) into treatment.

CONCLUSIONS

This pilot study describes an approach using the 3dMD photo system with Vultus software for measuring the progressive change in the nasal soft tissues. The 3dMD system was believed to be valuable for facial analysis in this setting.

Change in upper lip height and nostril sill after alveolar bone grafting in unilateral cleft lip alveolus patients

INTRODUCTION

Alveolar bone grafting is known to reduce nasal asymmetry by supporting a defective alar base and a sunken nostril. However, there are no studies which include details of changes to the upper lip with appropriate measurements. The purpose of this study was to measure the change in the upper lip height and nostril sill after alveolar bone grafting, using photogrammetry.

MATERIALS AND METHODS

The study included 18 unilateral cleft lip alveolus (UCLA) patients who were diagnosed with unilateral cleft lip and palate (mean age, 9.87 years). The patients underwent alveolar bone grafting with iliac bone between June 2007 and June 2008. The average follow-up period was 16.6 months. The average bone graft volume was 2.39 cm(3). We obtained photographs of the frontal, lateral and basal views using standardised photographic techniques. We defined 14 landmarks and measured the distance of 11 points (distance items) for the determination of upper lip height, upper lip projection and nostril sill elevation. We defined the proportion index as the ratio of the cleft side to non-cleft side or reference line (R). We compared the preoperative proportion index with the postoperative proportion index for each distance items.

RESULTS

The height of the upper lip increased significantly in four of five distance items. The projection of the upper lip was more prominent, but it was not statistically significant. The nostril sill was significantly elevated in all four distance items.

CONCLUSION

The height of the upper lip was elongated and the nostril sill was elevated after alveolar bone grafting in UCLA patients.

Three-dimensional photogrammetry for surgical planning of tissue expansion in hemifacial microsomia

BACKGROUND

We aim to illustrate the applications of 3-dimensional (3-D) photogrammetry for surgical planning and longitudinal assessment of the volumetric changes in hemifacial microsomia.

METHODS

A 3-D photogrammetric system was employed for planning soft tissue expansion and transplantation of a vascularized scapular flap for a patient with hemifacial microsomia. The facial deficiency was calculated by superimposing a mirror of the normal side on the preoperative image. Postsurgical volumetric changes were monitored by serial superimposition of 3-D images.

RESULTS

A total of 31 cm(3) of tissue expansion was achieved within a period of 4 weeks. A scapular free flap measuring 8 cm × 5 cm was transplanted to augment the facial deficiency. Postsurgical shrinkage of the flap was observed mainly in the first 3 months and it was minimal thereafter.

CONCLUSION

3-D photogrammetry can be used as a noninvasive objective tool for assessing facial deformity, planning, and postoperative follow-up of surgical correction of facial asymmetry.

Comparison of facial soft tissue measurements on three-dimensional images and models obtained with different methods

AIM

The aim of this study was to compare the clinical facial soft tissue measurements with the measurements of facial plaster cast, three-dimensional scanned facial plaster cast, 3-dimensional digital photogrammetrical images, and three-dimensional laser scanner images.

MATERIALS AND METHODS

Three-dimensional facial images of 15 adults were obtained with stereophotogrammetry and a three-dimensional laser scanner. Facial models of subjects were obtained using silicone impression and were scanned. Landmarks were marked on the subjects and plaster casts, digitized on three-dimensional models, and measured in Mimics 12.0 software (Materialise's Interactive Medical Image Control System, Leuven, Belgium).

RESULTS

No statistically significant differences were found between all three-dimensional measurement methods in mouth width, philtrum median height, and nasal width. Comparison of clinical measurements with facial plaster cast measurements revealed that philtral width, nasal tip protrusion, and right lip and nostril heights were wider and longer in clinical measurements than in facial plaster cast measurements. Comparison of clinical measurements to the laser scanned and stereophotogrammetric model measurements revealed that philtrum lateral and lip heights and philtral width were significantly different between methods. When laser scanned and stereophotogrammetric measurements were compared, significant differences were observed in lip and nostril heights.

CONCLUSIONS

Facial impression may be problematic owing to the depression caused by the impression material especially on the tip of the nose. Laser scanning is not sensitive enough to visualize the deeper indentations such as nostrils. Stereophotogrammetry is promising for three-dimensional facial measurements and even will be better when color identification between mucocutaneous junctions of the lip region is achieved.

Digital three-dimensional image fusion processes for planning and evaluating orthodontics and orthognathic surgery. A systematic review

The three important tissue groups in orthognathic surgery (facial soft tissues, facial skeleton and dentition) can be referred to as a triad. This triad plays a decisive role in planning orthognathic surgery. Technological developments have led to the development of different three-dimensional (3D) technologies such as multiplanar CT and MRI scanning, 3D photography modalities and surface scanning. An objective method to predict surgical and orthodontic outcome should be established based on the integration of structural (soft tissue envelope, facial skeleton and dentition) and photographic 3D images. None of the craniofacial imaging techniques can capture the complete triad with optimal quality. This can only be achieved by 'image fusion' of different imaging techniques to create a 3D virtual head that can display all triad elements. A systematic search of current literature on image fusion in the craniofacial area was performed. 15 articles were found describing 3D digital image fusion models of two or more different imaging techniques for orthodontics and orthognathic surgery. From these articles it is concluded, that image fusion and especially the 3D virtual head are accurate and realistic tools for documentation, analysis, treatment planning and long term follow up. This may provide an accurate and realistic prediction model.

Registration of 3-dimensional facial photographs for clinical use

PURPOSE

To objectively evaluate treatment outcomes in oral and maxillofacial surgery, pre- and post-treatment 3-dimensional (3D) photographs of the patient's face can be registered. For clinical use, it is of great importance that this registration process is accurate (< 1 mm). The purpose of this study was to determine the accuracy of different registration procedures.

MATERIALS AND METHODS

Fifteen volunteers (7 males, 8 females; mean age, 23.6 years; range, 21 to 26 years) were invited to participate in this study. Three-dimensional photographs were captured at 3 different times: baseline (T(0)), after 1 minute (T(1)), and 3 weeks later (T(2)). Furthermore, a 3D photograph of the volunteer laughing (T(L)) was acquired to investigate the effect of facial expression. Two different registration methods were used to register the photographs acquired at all different times: surface-based registration and reference-based registration. Within the surface-based registration, 2 different software packages (Maxilim [Medicim NV, Mechelen, Belgium] and 3dMD Patient [3dMD LLC, Atlanta, GA]) were used to register the 3D photographs acquired at the various times. The surface-based registration process was repeated with the preprocessed photographs. Reference-based registration (Maxilim) was performed twice by 2 observers investigating the inter- and intraobserver error.

RESULTS

The mean registration errors are small for the 3D photographs at rest (0.39 mm for T(0)-T(1) and 0.52 mm for T(0)-T(2)). The mean registration error increased to 1.2 mm for the registration between the 3D photographs acquired at T(0) and T(L). The mean registration error for the reference-based method was 1.0 mm for T(0)-T(1), 1.1 mm for T(0)-T(2), and 1.5 mm for T(0) and T(L). The mean registration errors for the preprocessed photographs were even smaller (0.30 mm for T(0)-T(1), 0.42 mm for T(0)-T(2), and 1.2 mm for T(0) and T(L)). Furthermore, a strong correlation between the results of both software packages used for surface-based registration was found. The intra- and interobserver error for the reference-based registration method was found to be 1.2 and 1.0 mm, respectively.

CONCLUSION

Surface-based registration is an accurate method to compare 3D photographs of the same individual at different times. When performing the registration procedure with the preprocessed photographs, the registration error decreases. No significant difference could be found between both software packages that were used to perform surface-based registration.

3D digital stereophotogrammetry: a practical guide to facial image acquisition

The use of 3D surface imaging technology is becoming increasingly common in craniofacial clinics and research centers. Due to fast capture speeds and ease of use, 3D digital stereophotogrammetry is quickly becoming the preferred facial surface imaging modality. These systems can serve as an unparalleled tool for craniofacial surgeons, proving an objective digital archive of the patient's face without exposure to radiation. Acquiring consistent high-quality 3D facial captures requires planning and knowledge of the limitations of these devices. Currently, there are few resources available to help new users of this technology with the challenges they will inevitably confront. To address this deficit, this report will highlight a number of common issues that can interfere with the 3D capture process and offer practical solutions to optimize image quality.

Effect of alveolar bone grafting on nasal morphology, symmetry, and nostril shape of patients with unilateral cleft lip and palate

OBJECTIVE

To evaluate nasal morphology, symmetry, and nostril shape in patients with unilateral cleft lip and palate following mixed-dentition alveolar bone grafting.

DESIGN

Prospective stereophotogrammetric study.

SETTING

Hospital-based.

PATIENTS

Thirty-nine patients with a history of repaired unilateral cleft lip and palate who received an iliac crest alveolar bone graft were recruited prospectively to participate in the study. Each patient served as his/her own control.

INTERVENTIONS

Partial facial impressions of all patients were acquired before and a minimum of 6 months after the alveolar bone grafting procedure. Image acquisition and analysis of the casts constructed from these models were carried out using three-dimensional stereophotogrammetry.

MAIN OUTCOME MEASURES

Surface-based registrations and linear measurements were performed to assess nasal morphology and nostril shape. A modified Procrustes technique was used to determine the change in nasal symmetry. A two-tailed, paired t test and an analysis of covariance were used to assess statistical significance.

RESULTS

Significant side-to-side asymmetry exists in the nasal region of patients with unilateral cleft lip and palate, both before and after alveolar bone grafting. No significant changes were observed between pre-alveolar bone graft and post-alveolar bone graft images based on linear measurements, asymmetry scores, and registrations. Gender and surgeon were not significant factors.

CONCLUSION

Under the conditions of this study, mixed-dentition alveolar bone grafting appears to have no significant long-term effect on nasal morphology, symmetry, or nostril shape.

Validity and reliability of craniofacial anthropometric measurement of 3D digital photogrammetric images

BACKGROUND

Direct anthropometry performed during a patient examination is the standard technique for quantifying craniofacial dysmorphology, as well as for surgical planning and outcome assessment. Several new technologies have been designed to computerize anthropometric measurements, including three-dimensional (3D) digital photogrammetry. These digital systems have the advantage of acquiring patient craniofacial surface images quickly and noninvasively. Before morphometry using digital photogrammetry can be applied in clinical and research practice, it must be assessed against direct anthropometry.

OBJECTIVE

To evaluate the validity and reliability of facial anthropometric linear distances imaged by 3D digital photogrammetry with respect to direct anthropometry. DESIGN, SETTING, PARTICIPANTS, MEASURES: Standard craniofacial distances were directly measured twice on 20 normal adult volunteers. Craniofacial surfaces were also imaged using the 3dMDface digital photogrammetry system, and distances were digitally measured twice for each subject. Validity measures of accuracy and bias (for direct versus digital measurements) and reproducibility measures of precision and test-retest reliability (for repeated sets of digital measurements) were computed.

RESULTS

Seventeen of the 18 direct measurements correlated highly with digital values (mean r = 0.88). The correlation for one measurement (upper prolabial width) was not statistically significant. The overall precision of all 17 digital measurements was less than 1 mm, and the reliability was high (mean r = 0.91).

CONCLUSIONS

Craniofacial anthropometry using the 3dMDface System is valid and reliable. Digital measurements of upper prolabial width may require direct marking, prior to imaging, to improve landmark identification.