|Year : 2017 | Volume
| Issue : 3 | Page : 50-60
Reliability and validity of tomographic anthropometric parameters in patients with cleft lip and palate
Tatiana Izchel Castillo Torres, Marcia Rosario Perez Dosal, Ariana Cruz Sandoval, Norma Mónica Dominguez Martinez
Fernando Ortiz Monasterio, Craneofacial Anomalies Foundation at Health Services, Angeles Group, Angeles del Pedregal Hospital, Mexico City, Mexico
|Date of Web Publication||21-Nov-2017|
Tatiana Izchel Castillo Torres
Hospital Angeles Del Pedregal, Oficce # 6, Heroes de Padierna, 10700 Mexico City
Source of Support: None, Conflict of Interest: None
Background: The main stigma of cleft lip and palate (CLP) is the nasal asymmetry, anthropometry helps to evaluate results, the computerized tomography (TC) assesses the maxillary conditions, and the three-dimensional (3D) reconstruction can aide to evaluate soft tissues. Repeatability and validity of tomographic anthropometric parameters of nasal symmetry have not been estimated before. Aims: The aim of the study was to estimate the repeatability and validity of tomographic nasal symmetry anthropometric parameters in patients with CLP. Settings and Design: This study was a cross-sectional study. The sample size was 63 measurements in patients with CLP 9–18 years. Variables such as sex, age, clinics and tomographic anthropometric measurements, Sn-C, Sn-Prn, A, Gsup-Gbase, Ac-Prn, C, D, Nt-Nm/Nb-Nl, La med-La lat, Sa inf-Sa sup, Sn-Al, B, Sn-Ac, Sn-Sbal were used. Subjects and Methods: Two measurements of reconstructed anthropometric tomographic 3D were evaluated twice to assess repeatability. Validity of tomographic was calculated comparing with clinical anthropometric measurements (gold standard). Statistical Analysis: Intraclass correlation coefficient was used to assess the repeatability and the individual differences for criterion validity. Results: Fifty-one subjects were included, mean age was 12.82 ± 2, and 64.71% were males. Sn-C, Sn-Prn, A, Gsup-Gbase, C, D, Nt-Nm/Nb-Nl, La med–La lat, Sa sup–Sa inf, Sn-Al, B, Sn–Ac, and Sn-Sbal had a repeatability CCI above 0.70. For validity, Sn-Prn, Prn-Ac, D, Nt-Nm/Nb-Nl, La med-La lat, Sa sup-Sa inf, Sn-Al, B, Ac-Sn, and Sn-Sbal tomographic measurements showed a mean difference ≤1 mm in comparison with clinical anthropometric measurements. Conclusions: Nine tomographic measures were closer to clinical measurements. The tomographic measures are a good way to evaluate nose symmetry in patients with CLP.
Keywords: Cleft lip and palate, nasal asymmetry, tomographic anthropometry
|How to cite this article:|
Torres TI, Dosal MR, Sandoval AC, Martinez NM. Reliability and validity of tomographic anthropometric parameters in patients with cleft lip and palate. J Cleft Lip Palate Craniofac Anomal 2017;4, Suppl S1:50-60
|How to cite this URL:|
Torres TI, Dosal MR, Sandoval AC, Martinez NM. Reliability and validity of tomographic anthropometric parameters in patients with cleft lip and palate. J Cleft Lip Palate Craniofac Anomal [serial online] 2017 [cited 2022 May 25];4, Suppl S1:50-60. Available from: https://www.jclpca.org/text.asp?2017/4/3/50/218895
| Introduction|| |
The cleft lip and palate (CLP) is characterized by the lack fusion of facial process. The cleft closure returns the function, esthetics, and improve quality of life.,
The main stigma of CLP is the nasal asymmetry, anthropometry helps to evaluate results, and the gold standard is the clinical anthropometry., The Computerized Axial Tomography (TAC) assess the conditions of the maxillary in patients with CLP and the three-dimensional (3D) reconstruction can aide to evaluated soft tissues.
The aim of this study is to estimate the validity of 3D tomographic anthropometric parameters that determine nasal symmetry in patients with CLP comparing them with clinical anthropometry, for a future submitting them panel Delphi to perform measuring instrument nasal asymmetry CLP.
| Subjects and Methods|| |
This study was a comparative cross-sectional study to validate a diagnosis test.
About 9–18-year-old children with unilateral CLP (UCLP) who were treated at CLP Program in a General Hospital in México City, during the period comprised between February 2012 and June 2014.
A consecutive selection of subjects with UCLP was done during the medical evaluation for alveolar bone graft.
The sample size was estimated with application Power Analysis Simple Size of PASS 15 software (NCSS PASS 15. NCSS, LLC. 2015 Kaysville, USA. www.ncss.com) using the intraclass correlation coefficient (ICC) formula, where it was assumed a 0.8 power value, 0.05 significance level (1.96 Z value), and an expected ICC value of 0.70 and 0.50. to obtain a total of 63 antropometric measurements, where it was assumed a 0.8 power value, 0.05 significance level (1.96 Z value), and an expected ICC value of 0.70 and 0.50.
Ethics approval and consent to participate
This research was considered with minimum risk according to the Mexican General Health Act and was approved by the Institutional Review Board of Hospital with the number 18-27-2013. Participants and their parents signed the release form in each case.
Criterion validity variable was 3D tomographic anthropometric measures for nasal symmetry, compared with clinical anthropometric measures (gold standard) [Table 1].
The sociodemographic variables were age, sex, number of surgical procedures, and surgical technique for lip closure.
Clinical anthropometric measures
A digital Vernier Surtek® model 122204 was used to obtain the clinical anthropometric measures from tissues, which were taken directly avoiding excessive pressure that could lead to tissue deformation and with the children sited at Frankfort plane parallel to the floor. Measures were taken bilaterally, starting with the left side [Figure 1]. The Digital Vernier was calibrated previous to each children evaluation.
|Figure 1: Clinical anthropometric measures. (a) Nasal groove vertical distance, (b) nostril height, (c) columella length, (d) alar length, (e) long axis of the nostril “Nt-Nm/Nb-Ni, (f) long axis of the nostril “Lamed- La lat”, (g) alar width (Sn-Al), (h) alar base width (Sn-AC), (i) width inner alar base (Sn-Sbal)|
Click here to view
The 14 clinical anthropometric measures were the following:
- Seven vertical parameters: Columella length (Sn-C), nasal tip protrusion (Pr-Sn), nostril height (A), nasal groove vertical distance (Gsup-Gbase), alar length (Ac-Prn), nasal base (C), and top alar groove (D)
- Three axes: Long axis of the nostril (Nt-Nm/Nb-Nl), long axis of the nostril (La med-La lat), and short axis of the nostril (Sa sup-Sa inf)
- Four horizontal parameters: Alar width (Sn-Al), nostril width (B), alar base width (Sn-Ac), and inner alar base width (Sn-Sbal).
To examine the interobserver concordance, clinical anthropometric measures were taken by two different observers. The intraobserver concordance was evaluated in one observer who took two times all the measures, separated for an interval of 30 days.
The results of intra- and inter-observer concordance are shown in [Table 2].
|Table 2: Test-Retest Reliability of Direct anthropometric Method (Clinical anthropometric measures)|
Click here to view
Three-dimensional tomographic anthropometric measures
The anthropometric measures were taken also using a computerized axial tomography scan (TAC); 3D-reconstructed soft tissues images were obtained using the software PACS DVD®. After that, anthropometric measures were acquired using the standardized anthropometric points [Figure 2] defined in a manual of tomographic procedures.
|Figure 2: Tomographic three-dimensional anthropometric landmarks labeled. (a) Front view landmarks; C, D, Gsup (b) submental view landmarks; Prn, Gsup, A, B, C, Sn, Gbase, Sbal, Al (c) profile view landmarks; Prn, Ac|
Click here to view
The tomographic anthropometric measures were taken as follows [Figure 3]:
|Figure 3: The three-dimensional tomographic anthropometric measures. (a) submental view tomographic anthropometric measures: 4 vertical parameter (Sn-C, Pr-Sn, A, Gsup- Gbase), 3 axes (Nt-Nm/Nb-Nl, la med-La lat and Sa sup- Sa inf) and 3 horizontal parameters (Sn-Al, B and Sn-Sbal). (b) Frontal view tomographic anthropometric measures; 2 vertical (c and d). (c and d) 3/4 profile and profile view tomographic anthropometric measures: one vertical parameter (Ac-Pm) and one horizontal parameter (Sn-Ac)|
Click here to view
- Ten parameters using a submental view: Four vertical parameters (Sn-C, Pr-Sn, A, and Gsup-Gbase), the three axes (Nt-Nm/Nb-Nl, la med-La lat, and Sa sup-Sa inf), and three horizontal parameters (Sn-Al, B, and Sn-Sbal)
- Two vertical parameters with a frontal view (C and D)
- Two parameters with a three-fourth profile and profile view: One vertical parameter (Ac-Prn) and one horizontal parameter (Sn-Ac).
To estimate the repeatability of 3D reconstruction of soft tissues, images were generated and measured twice by an observer with an interval of 30 days.
All statistical analyses were conducted using STATA software (version 12.0; Stata Corporation, TX, USA). Numerical variables were expressed as mean ± standard deviation and categorical variables were showed as frequencies.
The reliability of 3D tomographic anthropometric measures was calculated with the ICC. The criterion validity was evaluated using the Bland–Altman analysis for individual differences, comparing the first clinical evaluations of both 3D tomographic and clinical anthropometric measures.
| Results|| |
We studied 51 children with UCLP with a mean age of 12.8 ± 2.6 years old (range: 9–18 years old), 64.7% males and 35.3% females.
Nasal repair during their first surgical procedures was observed in the 90% of children.
Millard technique was the most frequent lip closure (82.3%) and Tennison technique was done to 17.7% of subjects. The mean of number of surgical procedures was 4.2 ± 1.9.
Reliability of three-dimensional tomographic anthropometric measures
A total of 2856 3D tomographic anthropometric measurements and 14 anthropometric parameters were analyzed. The 92.8% of anthropometric parameters (13/14) had an ICC >0.70. The lowest ICC corresponded to Ac-Prn parameters (ICC = 0.57), whereas the Sa sup-Sa inf parameter had the highest one (ICC = 0.84). The anthropometric parameters with an ICC >0.70 are shown in [Table 3].
|Table 3: Test-Retest Reliability of 3D tomographic anthropometric measures|
Click here to view
Criterion validity of three-dimensional tomographic anthropometric measures
The 3D tomographic anthropometric measures were considered valid when the mean absolute difference compared with the clinical anthropometric measures was ≤1.0 mm [Table 4].
The 3D tomographic nasal base measure (C) showed the highest mean absolute difference in comparison with the clinical measure (−3.11 ± 3.50 mm), indicating that the tomographic nasal base measure is higher than the clinical method. [Figure 4] shows Bland–Altman plot.
|Figure 4: Bland–Altman plot. Bland–Altman plot to compare tomographic versus clinical anthropometric (gold standard). In this graphical method the mean absolute differences (MAD) are plotted against of the “gold standard” method. (a) Alar width (Sn-Al) The MAD is –0.01, (±1.90) the values are distributed at random and located within the confidence limits, three outliers measurements are observed. (b) Nasal base (c) The MAD is –3.11, (±3.50) the values are at random and located within the confidence limits, tomographic measures were greater than clinics, ten outliers measurements are observed. (c) Nostril width (b) The MAD is 0.71, (±1.49) the values are distributed at random and located within the confidence limits, four outliers measurements are observed|
Click here to view
| Discussion|| |
Multiple studies focus on clinical or photographical evaluation of the surgical or presurgical orthopedic treatment results; however, few studies evaluate the reliability and validity of anthropometric parameters before providing results and clinic recommendations. On the other hand, there are no standardized norm agreements to evaluate the aesthetic results of patients with CLP and other craniofacial malformations and also has been observed that many of nose symmetry evaluations tend to be skewed because of uncertain data and invalidated methods to provide objective and quantitative evidence. The use of anthropometric measurements for the nasal symmetry evaluations requires reliability and validity evaluation methods for measuring and planning procedures and performs clinical monitoring.
Our repeatability outcome from the tomographic anthropometric measures had a CCI >0.70 (good concordance) excepting the alar length (Prn-Ac), indicating that the TAC 3D with software PACS DVD® can be a reliable nasal assessment method in the CLP patients. This coincides with the reliability estimated of the facial evaluating methods in the same CLP population in the research by Li et al., Nkenkeet al., and Schwenzer-Zimmerer et al.
The anthropometric Gbase and Gsup points are evaluated by Nkenke et al. separately with CCI >0.90, while estimating repeatability of TAC 3D, the distance was taken between these two anthropometric points to assess the nasal groove vertical distance (Gbase-Gsup). In our study, the CCI of this anthropometric point decreased; however, the TAC 3D repeatability good concordance was, taking into consideration that this is a common deformity by the depression of nasal dome consequence of displacement of cartilage and nasal muscles.,,,
Regarding the reproducibility, the alar length (Prn-Ac) was the tomographic anthropometric measurement with the lower CCI (0.57), which is related to the CLP patient's anatomy. According to Li et al., regarding the evaluation of the 3D photogrammetry, the low CCI value may be due to the location of the alar curvature (Ac), as it can be superposed in the reconstruction of shadows, edges, or reflections, which makes the anatomic location more difficult, according to the operational definitions. Aynechi et al. also report that one of the main problems locating the pronasal (Prn) is that it can be observed as a double structure in patients with CLP; therefore and due to the moderate reliability of this anthropometric point, a consensus has to be done to determine its importance in assessing the nasal symmetry in patients with CLP.
The anthropometric points taken from Nakamura et al., who propose clinical guidelines for treatment, do not report the reliability of anthropometric parameters, reason why it was decided to evaluate them individually: nostril height (A), nostril width (B), nasal base (C), and top alar groove (D), as a result, a CCI >0.70 was obtained, showing a good concordance in TAC 3D with software PACS DVD®.
In our study, the two longitudinal axes: Nt-Nm/Nb-Nl and La med-La Lat had the same CCI (0.77) although it is not an excellent concordance, as reported in the evaluation of photographic indirect anthropometry by Nkenke et al. and Nagy and Mommaerts both with ICC values >0.90. The TAC 3D has a good concordance to analyze the longitudinal axis either with the inner of the nostril or performing the intersections of the four walls of the nostril.
To estimate repeatability, methodology consisted in reconstruct and measured two different TACs in the same patient, compared to other studies,,,, in which the two measurements to evaluate repeatability were made on same anthropometric points label, this may overestimate the accuracy; therefore, our results provide greater accuracy and repeatability decreases bias information.
To control the memory bias in our study, the time interval of the first and second measurements was 1 month, this provides advantages over studies reported by Nkenke et al., where those measurements were made one in a growth peak, and the second measurement interval was after 6 months, biological facial changes were not under control. Other studies as reported by Weinberg et al. and Wong et al. perform the second measurement 24 h later. Li et al. wait 72 h for the second evaluation and Aynechi et al. perform the second measurement with an interval of 1 week, but these short lapses between the first and the second measurement may lead to an overestimation of the reliability of the measurements from not controlling memory bias.
The ideal analysis is the coefficient correlation intraclass to estimate the reproducibility, evaluation of studies reporting reliability of new techniques of craniofacial assessment by error method, and mean absolute differences;,, these two tests do not measure the degree of similarity, only measure the magnitude between the differences of the first and second evaluation using the same technique by the same assessor and not the consistency or similarity of the technique to make assessments as CCI reports, we analyzed repeatability with CCI, this is an advantage in our study.
The repeatability of the 3D tomographic anthropometric measurements using the software PACS DVD® had ICC >0.70 as reported in other studies that evaluated the reliability of techniques craniofacial assessment 3D,,,, this study analyzed a larger sample size than those articles reported by other authors; therefore, our statistical power is higher and the repeatability estimate is more accurate.
The CLP is a public health problem in our country and the nasal symmetry is one of the main goals of treatment, validation of reconstruction of soft tissue with the software PACS DVD® in this population provides an advantage over validation; the other techniques facial assessment conducted in patients with or without alteration visible craniofacial or healthy patients.,,
The magnetic resonance imaging technique is a more sensitive diagnostic test for soft tissues; however, it presents some disadvantages: longer time to take resonance and high cost, in Mexico, computed tomography (CT) is used to evaluate the conditions of the maxillary, it is a diagnostic method that is stored in the hospital system, and although it represents a minimal radiation to the patient, this study serves to perform various reconstructions both soft tissue and hard tissue, and according to our findings of validity measurements on soft tissues could be performed through CT to analyze surgical results and clinical follow up without the need to measure the patient directly.
The evaluation of the nasal symmetry with TAC 3D reduces distortions created by the movement, shadows, or insertion of facial hair; this offers advantages over other systems craniofacial scanning, to capture an image in <2 s without the need to anesthetize the patient.,,
To estimate the validity of the tomographic, the anthropometry points are not marked directly in the face of patients during the taking of the TAC, as reported in previous studies,,,, to avoid information bias and overestimate the values of the TAC 3D.
In the estimation results of validity, seven of the 14 tomographic parameters had a mean absolute difference with a negative value, which reveals that the tomographic anthropometric measures tend to overestimate distance clinical anthropometric parameters, this is consistent with the analysis by Aynechi et al.; in the validation of the 3D MDface, the proposed system to make indirect measurements can register greater than those taken directly distances.
Ten out of the 14 3D anthropometric parameters, CT had a mean absolute difference of <1 mm and three had a difference of <2 mm, although these anthropometric parameters are not valid according to our hypothesis, could be considered valid according to studies on the validity of other methods of facial asessment,,, where a mean absolute difference of the methods evaluated <2 mm do not have clinical significance. Moreover, the NASAL groove vertical distance (Gbase-Gsup) and nasal base (C) have a difference >1.5 mm average, which according to Fourie et al., these values begin to be clinically significant.
The estimate of the criteria validity in our study was performed with analysis of individual differences and also to identify any bias and extreme values in the measurements were plotted [Figure 4]. This analysis offers advantages for criterion validity of quantitative variables compared to studies by Weinberg et al., who estimate the validity of a method of facial evaluation with Student's t-test in variables with normal distribution and Wilcoxon nonnormal distribution, analyzes with t-student, for this type of validity serve for comparison of means between assessment methods; however, for the sample size analyzed, we can say that differences in the averages of these studies are not representative to approve valid judgment, Wong et al. made a criterion validity and analysis is performed with Pearson's correlation coefficient (r), the results of its validity show an almost perfect correlation of the two methods evaluated; however, this analysis identifies the linear trend of the two methods evaluated and does not provide information about the measurement bias, extreme values, or the magnitude of difference between the compared methods.
In this study, direct anthropometry was performed in patients' soft tissues and even though there are validations of new methods of facial assessment, the direct anthropometry is referenced in mannequins, dead people's heads, or plaster models, these studies have disadvantages since they are not being assessed directly with the gold standard in soft or hard tissues directly from live persons to evaluate the validity of these methods that may be overestimated as reported by Aynechi et al.
In our study, the columella length (Sn-C) was the structure with smaller length having an average of 6.18 mm, the estimation of the validity of this anthropometric parameter was higher than established, with a mean absolute difference of 1.42 mm, which coincides with that reported by Li et al. and Ghoddousi et al., who propose that the shorter structures difficult their location and measurement for their validation.
The anthropometric parameter for the nasal base (C), presented a greater mean absolute difference of −3.11 mm, this alteration may be due to the bias of information in the clinical measurement as reported by Wong et al. since the nose is a structure used to breath, gesticulate, flashing, or closing their eyes excessively, patients can move and it can give shorter measurements than in 3D TAC; therefore, it should be tested if this anthropometric point presents alterations in clinical or tomographic measurement. It is not recommended to use this anthropometric measurement in routine clinical or tomographic evaluation.
Our study presents only 14 anthropometric measurements in contrast with those studies that evaluated more than 18 points,,,, unlike studies that measure all the facial structures (eyes, ears, nose, and mouth), our study, considering that the nasal symmetry is one of the main objectives, collected only the anthropometric parameters that measure the nasal structure in vertical, horizontal, and axes dimensions.
Although the search initially proposed 18 anthropometric measures, we decided to remove the anthropometric measure with similar operational definitions but with a different name, anthropometric measure as they are alar (Al) measured by Nkenke et al. and Yamada et al. as more nasal side of the dome (G lat). Nakamura et al. report the anthropometric point of the nostril width (B) without reliability data, Nagy named it medial nose to lateral nose (Nm-Nl), while Yamada et al. describe this point as (Nos med-Nos lat). Nakamura et al. reports nostril height (A), and performs the same evaluation Nagy and Mommaerts named it Nasal tip-Nasal base.
| Conclusions|| |
- The RMI is the ideal technique to measure surfaces; however, the TAC 3D reconstruction with the software PACS DVD® in this study showed a good concordance in the reproducibility and validity when measuring nasal symmetry, therefore, this study provides benefits that can be taken such as the easy storage for communication and exchange of information by different health caregivers and avoid the need for expensive and sophisticated studies
- Being the software PACS DVD®, a program for hospital use, it can be used for analysis and multicenter studies without the need of clinically measuring the patient
- According to the results of reliability and validity, anthropometric measurements must undergo a consensus to determine which ones are statistically and clinically significant to develop a nasal symmetry instrument.
Financial support and sponsorship
Conflicts of interest
There are no conflicts of interest.
| References|| |
Cohen MM, Hennekam RC. Orofacial clefting syndromes: General aspects. In: Hennekam RC, Allanson JE, Krantz ID, editor. Gorlin's Syndromes of the Head and Neck. 4th
ed. New York, USA: Oxford University Press; 2001. p. 850-7.
Evans CA. Orthodontic treatment for patients with clefts. Clin Plast Surg 2004;31:271-90.
Van Beek AL, Hatfield AS, Schnepf E. Cleft rhinoplasty. Plast Reconstr Surg 2004;114:57e-69e.
Hood CA, Hosey MT, Bock M, White J, Ray A, Ayoub AF, et al.
Facial characterization of infants with cleft lip and palate using a three-dimensional capture technique. Cleft Palate Craniofac J 2004;41:27-35.
Farkas LG. Accuracy of anthropometric measurements: Past, present, and future. Cleft Palate Craniofac J 1996;33:10-8.
RadiologyInfo.org. Radiological Society of North America and American College of Radiology. Inc; c2012. Available from: http://www.radiologyinfo.org
. [Last updated on 2015 May 18; Last accessed on 2015 Jul 4].
Walter SD, Eliasziw M, Donner A. Sample size and optimal designs for reliability studies. Stat Med 1998;17:101-10.
Bland JM, Altman DG. Comparing methods of measurement: Why plotting difference against standard method is misleading. Lancet 1995;346:1085-7.
Li G, Wei J, Wang X, Wu G, Ma D, Wang B, et al.
Three-dimensional facial anthropometry of unilateral cleft lip infants with a structured light scanning system. J Plast Reconstr Aesthet Surg 2013;66:1109-16.
Nkenke E, Lehner B, Kramer M, Haeusler G, Benz S, Schuster M, et al.
Determination of facial symmetry in unilateral cleft lip and palate patients from three-dimensional data: Technical report and assessment of measurement errors. Cleft Palate Craniofac J 2006;43:129-37.
Schwenzer-Zimmerer K, Chaitidis D, Berg-Boerner I, Krol Z, Kovacs L, Schwenzer NF, et al.
Quantitative 3D soft tissue analysis of symmetry prior to and after unilateral cleft lip repair compared with non-cleft persons (performed in Cambodia). J Craniomaxillofac Surg 2008;36:431-8.
Ozsoy U, Demirel BM, Yildirim FB, Tosun O, Sarikcioglu L. Method selection in craniofacial measurements: Advantages and disadvantages of 3D digitization method. J Craniomaxillofac Surg 2009;37:285-90.
Nagy K, Mommaerts MY. Analysis of the cleft-lip nose in submental-vertical view, part I – Reliability of a new measurement instrument. J Craniomaxillofac Surg 2007;35:265-77.
Wong JY, Oh AK, Ohta E, Hunt AT, Rogers GF, Mulliken JB, et al.
Validity and reliability of craniofacial anthropometric measurement of 3D digital photogrammetric images. Cleft Palate Craniofac J 2008;45:232-9.
Aynechi N, Larson BE, Leon-Salazar V, Beiraghi S. Accuracy and precision of a 3D anthropometric facial analysis with and without landmark labeling before image acquisition. Angle Orthod 2011;81:245-52.
Nakamura N, Sasaguri M, Nozoe E, Nishihara K, Hasegawa H, Nakamura S, et al.
Postoperative nasal forms after presurgical nasoalveolar molding followed by medial-upward advancement of nasolabial components with vestibular expansion for children with unilateral complete cleft lip and palate. J Oral Maxillofac Surg 2009;67:2222-31.
Weinberg SM, Scott NM, Neiswanger K, Brandon CA, Marazita ML. Digital three-dimensional photogrammetry: Evaluation of anthropometric precision and accuracy using a Genex3D camera system. Cleft Palate Craniofac J 2004;41:507-18.
Fourie Z, Damstra J, Gerrits PO, Ren Y. Evaluation of anthropometric accuracy and reliability using different three-dimensional scanning systems. Forensic Sci Int 2011;207:127-34.
Weinberg SM, Naidoo S, Govier DP, Martin RA, Kane AA, Marazita ML, et al.
Anthropometric precision and accuracy of digital three-dimensional photogrammetry: Comparing the Genex and 3dMD imaging systems with one another and with direct anthropometry. J Craniofac Surg 2006;17:477-83.
Khambay B, Nairn N, Bell A, Miller J, Bowman A, Ayoub AF, et al.
Validation and reproducibility of a high-resolution three-dimensional facial imaging system. Br J Oral Maxillofac Surg 2008;46:27-32.
Ghoddousi H, Edler R, Haers P, Wertheim D, Greenhill D. Comparison of three methods of facial measurement. Int J Oral Maxillofac Surg 2007;36:250-8.
Yamada T, Mori Y, Minami K, Mishima K, Sugahara T, Sakuda M, et al.
Computer aided three-dimensional analysis of nostril forms: Application in normal and operated cleft lip patients. J Craniomaxillofac Surg 1999;27:345-53.
[Figure 1], [Figure 2], [Figure 3], [Figure 4]
[Table 1], [Table 2], [Table 3], [Table 4]