OBJECTIVES: Facial directional asymmetry research, including age-related changes, is crucial for the evaluation of treatment of craniofacial malformations/trauma in orthodontics, facial surgery and forensic sciences. The aim was to describe facial directional asymmetry (DA) in different age categories of adults using 3D methods. According to our hypothesis, facial shape DA (1) depends on sex; (2) differs among age groups; and (3) has wider variability in older age. MATERIAL AND METHODS: A cross-sectional sample of healthy Czech adults without craniofacial trauma or anomalies consisted of 300 3D facial models (151 females). The age-range in the study was between 20-80 years. The shape asymmetry of 28 3D landmarks was evaluated using geometric morphometrics and multivariate statistics. RESULTS: The manifestation of DA was similar in both sexes and in each age category; however, there were some statistical differences. In contrast to the ideal symmetrical face, the mean asymmetrical faces tended to create a slightly bent "C" shape of the midline. Therefore, the upper face was rotated slightly clockwise and the lower face counter-clockwise. The right eye was located slightly higher, with the nasal tip and mandibular region tilting to the left. Sex differences in facial DA were significant before the age of 40. DA was more significant in the youngest males than in the oldest, while the women's DA did not change. CONCLUSIONS: The DA patterns were similar in both sexes and in all age categories (a slightly bent C shape of the midline); however, some significant local differences between male age groups were found. A significantly more pronounced asymmetry compared to other age groups was found only in the youngest males from 20 to 40 years. Moreover, significant sexual dimorphism of DA rapidly decreased after middle age, likely caused by the same age-related changes of the face during aging.

• MeSH
• Facial Asymmetry * etiology   MeSH
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Young Adult MeSH
• Nose MeSH
• Sex Characteristics MeSH
• Cross-Sectional Studies MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Imaging, Three-Dimensional * MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Young Adult MeSH
• Male MeSH
• Aged, 80 and over MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

OBJECTIVES: This study investigates facial directional asymmetry (DA) in early childhood. Using 3D imaging, it aims to assess the DA progression in healthy controls and children with unilateral cleft lip (CL) and unilateral cleft lip and palate (UCLP) following early neonatal cheiloplasty and palatoplasty. MATERIALS & METHODS: The sample consisted of 105 children (groups: cleft 42, control 63) aged 0.2-2 years. DA was analysed using geometric morphometrics, including 3D landmark-based and polygonal mesh analyses. Multivariate statistics were used for assessing DA significance and age group differences. RESULTS: Controls showed no DA in landmarks and only mild protrusion of the right hemiface, increasing with age. In groups with cleft, DA was more pronounced in UCLP and especially in the middle of the face. While older UCLP children showed more asymmetrical faces, DA in children with CL became more comparable to that in controls with increasing age. Older children showed no statistical difference between control and CL in the landmark and polygonal maps parts. CONCLUSIONS: After surgical treatment, a DA pattern was identified, and it was specific for both cleft types and age categories. For both diagnoses, the most notable feature is the protrusion at the cleft site, likely related to post-surgical scarring, but in the UCLP group, it is also the hypoplastic nasal wing and a growth insufficiency of the cheek on the cleft side. CLINICAL RELEVANCE: 3D methodologies provide insight into asymmetry progression and surgical outcomes, supporting improved cleft management for enhanced aesthetic and functional results.

• Keywords
• 3D landmarks-based methods, Directional asymmetry, Facial development with cleft, Geometric morphometrics, Infancy & toddlerhood, Polygonal mesh analyses,
• MeSH
• Facial Asymmetry * diagnostic imaging   MeSH
• Infant MeSH
• Humans MeSH
• Child, Preschool MeSH
• Cleft Palate * surgery   diagnostic imaging   MeSH
• Cleft Lip * surgery   diagnostic imaging   MeSH
• Case-Control Studies MeSH
• Imaging, Three-Dimensional * MeSH
• Check Tag
• Infant MeSH
• Humans MeSH
• Male MeSH
• Child, Preschool MeSH
• Female MeSH
• Publication type
• Journal Article MeSH

Three-dimensional facial images are becoming more and more widespread. As such images provide more information about facial morphology than 2D imagery, they show great promise for use in future forensic applications, including age estimation and verification. This paper proposes an approach using random forests, a machine learning method, to develop and test models for classification of legal age thresholds (15 years and 18 years) using 3D facial landmarks. Our approach was developed on a set of 3D facial scans from 394 Czech individuals (194 males and 200 females) aged between 10 and 25 years. The dataset was retrieved from a sizable database of Central European faces - The FIDENTIS 3D Face Database. Three main types of input variables were processed using random forests: I) shape (size-invariant) coordinates of 3D landmarks, II) size and shape coordinates of 3D landmarks, and III) inter-landmark distances, angles and indices. The performance rates for the combinations of variables and age threshold were expressed in terms of sensitivity and specificity. The overall accuracy rates varied from 71.4%-91.5% (when the male and female samples were pooled). In general, higher accuracy was achieved for the age limit of 18 years than for 15 years. Whereas size-variant variables showed a better performance rate for the age limit of 15 years, the size-invariant variables (i.e., shape variables) were better for classifying individuals under 18 years. The verification models grounded on traditional variables (distances, angles, indices) yielded consistently higher performance rates on females than on males, whereas the inverse trend was observed for the models built on 3D coordinates. The results indicate that age verification based on 3D facial data with processing by the random forests method has high potential for further forensic or biometric applications.

• Keywords
• 3D facial models, Age estimation, Age verification, FIDENTIS database, Random forests,
• MeSH
• Anatomic Landmarks * MeSH
• Child MeSH
• Adult MeSH
• Humans MeSH
• Adolescent MeSH
• Young Adult MeSH
• Face anatomy & histology   MeSH
• Image Processing, Computer-Assisted MeSH
• Cross-Sectional Studies MeSH
• Machine Learning * MeSH
• Age Determination by Skeleton methods   MeSH
• Imaging, Three-Dimensional * MeSH
• Check Tag
• Child MeSH
• Adult MeSH
• Humans MeSH
• Adolescent MeSH
• Young Adult MeSH
• Male MeSH
• Female MeSH
• Publication type
• Journal Article MeSH

The virtual approach in physical and forensic anthropology is increasingly used to further analyze human remains, but also to propose new didactic means for visualization and dissemination of scientific results. Computerized facial approximation (FA) offers an alternative to manual methods, but usually requires a complete facial skeleton to allow for the estimation of the facial appearance of an individual. This paper presents the case of Tycho Brahe, Danish astronomer born during the XVIth century, whose remains were reanalyzed at the occasion of a short exhumation in 2010. Cranial remains of Brahe were poorly preserved, with only a partial facial skeleton, and virtual anthropology tools were used to estimate the missing parts of his skull. This 3D restoration was followed by a FA using TIVMI-AFA3D, subsequently textured with graphic tools. The result provided an interesting estimate that was compared with portraits of the astronomer. The impact of the missing data estimation was investigated by performing FAs on 10 complete test subjects and the same 10 subjects after cropping and estimating 50% of the landmarks (reproducing the preservation state of Tycho Brahe's cranial remains). The comparison between the FA based on the complete and incomplete skulls of the same subject produced a visual assessment of the estimation impact on FAs which is relatively low. This procedure is an alternative to manual methods and offers a reproducible estimate of a face based on incomplete cranial remains. Although the case report concerns a historical individual, the robust automatic estimation of missing landmarks followed by a FA has value for forensic caseworks as a support to the identification process.

• Keywords
• Computerized restoration, Facial reconstruction, Geometric morphometrics, Missing data, Virtual anthropology,
• MeSH
• Anatomic Landmarks MeSH
• History, 16th Century MeSH
• History, 17th Century MeSH
• Skull anatomy & histology   MeSH
• Humans MeSH
• Face anatomy & histology   MeSH
• Image Processing, Computer-Assisted * MeSH
• Software * MeSH
• Forensic Anthropology methods   MeSH
• Famous Persons MeSH
• Imaging, Three-Dimensional MeSH
• Check Tag
• History, 16th Century MeSH
• History, 17th Century MeSH
• Humans MeSH
• Publication type
• Journal Article MeSH
• Historical Article MeSH
• Portrait MeSH

BACKGROUND: Endoscopic endonasal transsphenoidal approaches are broadly used nowadays for a vast spectrum of pathologies sited in the anterior and middle cranial fossa. The usage of neuronavigation systems (neuronavigation) in these surgeries is crucial for improving orientations deeply inside the skull and increasing patient safety. METHODS: The aim of this study was to assess the use of optical neuronavigation, together with an intraoperative O-arm O2 imaging system, in a group of patients with hypophyseal adenoma that underwent a transnasal transsphenoidal surgery, and correlate the accuracy and its deviation during the navigational process against the use of conventional neuronavigation that uses preoperative MRI and CT scans. The overall group consisted of six patients, between 39 and 78 years old, with a diagnosis of hypophyseal adenoma. Patients were treated with an endoscopic transsphenoidal technique and all of them underwent preoperative MRI and CT scans of the brain. These images were used in the neuronavigation system StealthStation S7® during the surgery, where we defined two bony anatomical landmarks, such as a vomer or the origin of an intrasphenoidal septum, in each operated patient. The tip of the navigational instrument, under endoscopic control, pointed to these landmarks and the distance between the tip and the bony structure was measured on the neuronavigation system. Afterwards, intraoperative 3D x-ray imaging was performed via the mobile system O-arm O2® system with automatic transfer into the navigational system. Under endoscopic guidance, we localized the identical bony anatomical landmarks used in the previous measurement and re-measured the distance between the tip and bony landmark in images acquired by the O-arm. The results of both measurements were statistically compared. RESULTS: The mean error of accuracy during conventional neuronavigation with usage of preoperative CT and MRI scans was 2.65 mm. During the neuronavigation, with utilization of intraoperative 3D O-arm images, the mean error of accuracy 0 mm. These mean errors of accuracy (both measurement methods were compared by nonparametric Wilcoxon test) had a statistically significant difference (p = 0.043). CONCLUSIONS: Based on this preliminary clinical study, we conclude that the O-arm is capable of providing intraoperative x-ray 3D images in sufficient spatial resolution in a clinically feasible acquisition. The mean error of accuracy during intraoperative navigation, based on 3D O-arm scans at the skull base, is significantly lower compared to the usage of navigation using conventional presurgical CT and MRI images. This suggests the suitability of this method for utilization during endoscopic endonasal skull base approaches.

• Keywords
• Endonasal approach, Endoscopic skull base surgery, Neuronavigation, O-arm,
• MeSH
• Adenoma * diagnostic imaging   surgery   MeSH
• Skull Base * diagnostic imaging   surgery   MeSH
• Surgery, Computer-Assisted * methods   MeSH
• Adult MeSH
• Pituitary Gland * diagnostic imaging   surgery   MeSH
• Middle Aged MeSH
• Humans MeSH
• Magnetic Resonance Imaging MeSH
• Pituitary Neoplasms * diagnostic imaging   surgery   MeSH
• Neuronavigation methods   MeSH
• Intraoperative Period MeSH
• Pilot Projects MeSH
• Tomography, X-Ray Computed MeSH
• Prospective Studies MeSH
• Aged MeSH
• Imaging, Three-Dimensional MeSH
• Check Tag
• Adult MeSH
• Middle Aged MeSH
• Humans MeSH
• Male MeSH
• Aged MeSH
• Female MeSH
• Publication type
• Journal Article MeSH

OBJECTIVE: Fourier transform profilometry was used for the three-dimensional measurement of maxillary dental casts to analyze the size and shape of the palate. The objective of this study was to test the accuracy of the measuring system and determine the precision and reliability of the measurement METHODS: Images of dental casts were analyzed using newly developed measuring software. Based on five landmarks located on the alveolar ridge, the measuring software constructed 10 transversal sections of the palate. In each section profile, the width, area, and 23 height variables were assessed. SUBJECTS: Maxillary dental stone casts of 25 healthy girls, 14.1 to 15.3 years of age, were studied. RESULTS: The technical error of measurement exceeded 5% of the size of the measurement only in variables with means less than approximately 3 mm. In fact, such small absolute dimensions were exhibited only by the palate height in anterior profile 2 and the palate height at the margins of other profiles. Reliability of the measurements was found to be very high for the width and area of the profiles. For height measurements, the coefficient of reliability was slightly lower at the profile margins than near the midline. Nevertheless, only three height variables showed a coefficient of reliability lower than 0.90. The coefficients of reliability of other height measurements of profiles 3 through 10 were only sporadically lower than 0.97. CONCLUSION: With regard to the accuracy of the measuring system as well as the precision and reliability of the measurement, this method proved to be a suitable tool for studying palatal morphology.

• MeSH
• Fourier Analysis MeSH
• Cephalometry methods   MeSH
• Humans MeSH
• Maxilla MeSH
• Adolescent MeSH
• Palate anatomy & histology   MeSH
• Reproducibility of Results MeSH
• Imaging, Three-Dimensional methods   MeSH
• Models, Dental * MeSH
• Check Tag
• Humans MeSH
• Adolescent MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Evaluation Study MeSH
• Research Support, Non-U.S. Gov't MeSH

PURPOSE OF THE STUDY: Repeated measurements of the spine are absolutely necessary in children and adolescents affected by spinal deformities especially during their growing-up periods. To avoid risks of tissue damage from x-ray exposure, several methods for non-invasive measurement of the spinal curvature have been developed. One of them is the DTP-3 position system allowing for a three-dimensional measurement of anatomical landmarks (spinous processes) and the calculation of curvature angles in both the frontal and sagittal planes. We were interested to know whether the DTP-3 was precise enough to determine the true spinal curvature. MATERIAL AND METHODS: To determine the precision of the DTP-3 system, we constructed a model of the spine. The model was then repeatedly investigated by both the noninvasive and x-ray methods. The distortion of x-ray images caused by the central projection mechanism was considered and included in the calculation. In addition, a group of patients with scoliosis up to 40° was evaluated by both the DTP-3 system and x-ray (the latter according to Cobb's method). RESULTS: Differences in spatial coordinates between DTP-3 and x-ray examinations reached 20.9 mm in the frontal plane and 67.3 mm in the sagittal plane without distortion correction of x-ray images. The differences decreased below 1.5 mm after image distortion correction in each plane. Distortion correction had not the same effect for angle parameters as for coordinates. Differences between the DTP-3 angle parameters and Cobb's x-ray angles were below 4.7°, both without correction and after correction. The difference between DTP-3 angle parameters and Cobb's x-ray angles was -1.8° ± 3.0° (mean ± standard deviation) when measurement was performed on the patients with scoliosis. DISCUSSION: The goal of any clinical examination is to obtain data applicable to decision-making analysis. In the case of scoliosis it is necessary to report results in terms of Cobb's angle, which is the problem for all surface-dependent methods, especially in patients with double curves. A solution may be to define the maximal difference between noninvasive and x-ray methods that could be acceptable for good clinical practice. CONCLUSIONS: In this study we report good concordance between noninvasive and x-ray examinations of a modeled spinal deformity in terms of both angle and linear measurements. The same results were obtained for angle measurements in a group of patients with scoliosis up to 40°. Based on this study and our previous data we believe that the DTP-3 system can be introduced into clinical practice.

• MeSH
• Models, Anatomic MeSH
• Humans MeSH
• Adolescent MeSH
• Spine diagnostic imaging   pathology   MeSH
• Image Processing, Computer-Assisted * MeSH
• Radiography MeSH
• Scoliosis diagnosis   diagnostic imaging   MeSH
• Software MeSH
• Imaging, Three-Dimensional * MeSH
• Check Tag
• Humans MeSH
• Adolescent MeSH
• Male MeSH
• Female MeSH
• Publication type
• Journal Article MeSH
• Comparative Study MeSH
• Validation Study MeSH

PURPOSE OF THE STUDY: The aim of the study was to provide a method of measurement and data collection, based on morphologic analysis of the proximal humerus, that would facilitate precise placement of the humeral stem and would be easy to apply in clinical medicine in patients requiring shoulder arthroplasty. MATERIAL: Three groups of materials were used. Materials for the first and second groups were provided by the Department of Anatomy, First Faculty of Medicine, Charles University. The first group included 10 specimens (five left and five right humeral bones) obtained at routine anatomical dissection. The second group contained 110 so-called dry preparations from the collections of the Department of Anatomy and the third group comprised nuclear magnetic resonance (NMR) scans of 20 patients. To show spatial relationships between the proximal and the distal humerus, another coil was applied to the epicondylar region in addition to the one placed over the proximal humerus. METHODS: The first group material was used to study proximal humerus morphology and to determine reference points for the other two groups. The points were constructed to make seven planes perpendicular to the axis of the proximal humeral metaphysis. Based on the reference points, parameters of the proximal humerus were assessed in the defined planes also in the other two groups. We measured angles between the reference points and the transepicondylar line or the humeral head axis. The vertex of each angle was always placed in the point of intersection of the metaphyseal axis and the given transverse plane. Reference points of the greater tubercle were marked on the medial margin continuous with the intertubercular groove, on the lateral margin of the lesser tubercle and in the "deepest" place of the intertubercular groove. We also measured humeral head retroversion and the position of maximal bony mass of both the greater and the lesser tubercle (this parameter can be used with advantage for optimal insertion of screws in proximal humerus reconstruction). RESULTS: The angle between the medial margin of the greater tubercle and the humeral head axis was on average 164.8 degrees on the left side and 163.2 degrees on the right side; the angle between the great tubercle margin and the transepicondylar line was 137.0 degrees on the left humerus and 137.7 degrees on the right humerus. The lateral margin of the lesser tubercle and the humeral head axis formed on average an angle of 124.4 degrees and of 122.6 degrees on the right and the left side, respectively. The intertubercular groove/ humeral head axis relationship was 143.4 degrees and 144.8 degrees for the left and the right humerus, respectively, and the intertubercular groove/transepicondylar line angle was 115.6 degrees for the left and 119.5 degrees for the right humerus. The humeral head axis and the transepicondylar line made an angle of 27.8 degrees for the left and 25.3 degrees for the right humerus. These values corresponded to the angle of the humeral head retroversion. The reference point of maximal bony mass of the greater tubercle and the humeral head axis made an angle of 181.1 degrees and of 180.2 degrees for the left and the right humerus, respectively; between this point and the lesser tubercle was an angle of 120.2 degrees for the left and 126.9 degrees for the right humerus. DISCUSSION: One of the most important parameters in restoring shoulder function by alloplasty is humeral head retroversion. If this is not correct, ventral or, less frequently, dorsal instability of the shoulder may result. The correct setting of retroversion is guided by the transepicondylar line or several specific landmarks on the greater and the lesser tubercle of the humerus. Another important factor is the correct reconstruction of anatomic position of the greater and the lesser tubercle in relation to the insertion of rotator cuff muscles into the humeral head. Relationships of diaphyseal, metaphyseal and humeral head axes have been reported in the relevant literature dealing with proximal femoral morphology. None of the reports, however, has dealt with tubercular angles and position of the maximal body mass, which is a decisive factor for insertion of screws fixing the prosthetic stem. CONCLUSIONS: The values provided here can be used for a more precise construction of implants for shoulder replacement. The method of three-dimensional presentation of the proximal humerus may aid in a more exact implantation procedure during shoulder arthroplasty. An optimal position of the implant can also be based on parameters obtained from the healthy contralateral shoulder joint.

• MeSH
• Anthropometry MeSH
• Arthroplasty, Replacement * MeSH
• Humerus anatomy & histology   MeSH
• Humans MeSH
• Magnetic Resonance Imaging MeSH
• Shoulder Joint anatomy & histology   surgery   MeSH
• Rotator Cuff anatomy & histology   MeSH
• Imaging, Three-Dimensional MeSH
• Check Tag
• Humans MeSH
• Publication type
• English Abstract MeSH
• Journal Article MeSH

BACKGROUND: Variations observed in biomechanical studies might be attributed to errors made by operators during the construction of musculoskeletal models, rather than being solely attributed to patient-specific geometry. RESEARCH QUESTION: What is the impact of operator errors on the construction of musculoskeletal models, and how does it affect the estimation of muscle moment arms and hip joint reaction forces? METHODS: Thirteen independent operators participated in defining the muscle model, while a single operator performed 13 repetitions to define the muscle model based on 3D bone geometry. For each model, the muscle moment arms relative to the hip joint center of rotation was evaluated. Additionally, the hip joint reaction force during one-legged stance was assessed using static inverse optimization. RESULTS: The results indicated high levels of consistency, as evidenced by the intra- rater and inter-rater agreement measured by the Intraclass Correlation Coefficient (ICC), which yielded values of 0.95 and 0.99, respectively. However, the estimated muscle moment arms exhibited an error of up to 16 mm compared to the reference musculoskeletal model. It was found that muscles attached to prominent anatomical landmarks were specified with greater accuracy than those attached over larger areas. Furthermore, the variability in estimated moment arms contributed to variations of up to 12% in the hip joint reaction forces. SIGNIFICANCE: Both moment arm and muscle force demonstrated significantly lower variability when assessed by a single operator, suggesting the preference for employing a single operator in the creation of musculoskeletal models for clinical biomechanical studies.

• Keywords
• Hip joint, Moment arm, Musculoskeletal model, Variability,
• MeSH
• Models, Biological MeSH
• Biomechanical Phenomena MeSH
• Muscle, Skeletal * physiology   MeSH
• Hip Joint * physiology   MeSH
• Humans MeSH
• Check Tag
• Humans MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

BACKGROUND: Developmental instability is a component of non-genetic variation that results from random variation in developmental processes. It is considered a sensitive indicator of the physiological state of individuals. It is reflected in various ways, but in this study we focussed on its reflection in fluctuating asymmetry (FA) and morphological integration. AIM: To assess how, if at all, variations of facial morphology mirror developmental instability across childhood with respect to sex, growth rate and socioeconomic/environmental factors. SUBJECTS AND METHODS: A set of 210 three-dimensional facial models (of children aged between 6.3 and 14.3 years) originating from the FIDENTIS 3D Face Database was subjected to landmark-based methods of geometric morphometrics to quantify the degree of facial asymmetry and facial morphological integration. In addition, the association with age, sex, and socioeconomic factors was assessed. RESULTS: Our results showed a nonlinear increase of FA with age up to the age of 14 years. The pattern of sex-related variants in facial FA differed in relation to age, as girls exhibited higher values of FA than boys up to the age of 9 years. We found that a signal of modularity based on functional demands and organisation of the face is of particular importance. Here, girls exhibited higher morphological covariation among modules. During more rapid adolescence-related growth, however, covariation among modules at the asymmetrical level decreased in both sexes. CONCLUSION: We can conclude that facial morphology was shown to be strongly integrated, particularly until adolescence. This covariation can facilitate an increase of FA. In addition, the results of this study indicate there is a weak association between socioeconomic stress and facial asymmetries. In contrast, sex and growth rate are reflected in developmental instability.

• Keywords
• Facial variability, developmental instability, facial integrity, facial modularity, fluctuating asymmetry,
• MeSH
• Facial Asymmetry * genetics   MeSH
• Child MeSH
• Head MeSH
• Humans MeSH
• Adolescent MeSH
• Face * MeSH
• Socioeconomic Factors MeSH
• Check Tag
• Child MeSH
• Humans MeSH
• Adolescent MeSH
• Male MeSH
• Female MeSH
• Publication type
• Journal Article MeSH