Xiangyang Ju

• Head of Image Processing at NHS Greater Glasgow and Clyde

Highlights PointNet trained with preprocessed point clouds of facial movements can provide accurate assessment of facial paralysis. What are the main findings? The accuracy of the new approach was higher than 95%. The objective approach offers better assessment than the subjective approach. What are the implications of the main findings? The automa...

Background Automatic landmarking software packages simplify the analysis of the 3D facial images. Their main deficiency is the limited accuracy of detecting landmarks for routine clinical applications. Cliniface is readily available open-access software for automatic facial landmarking, its validity has not been fully investigated. Objectives Eval...

Background The facial landmark annotation of 3D facial images is crucial in clinical orthodontics and orthognathic surgeries for accurate diagnosis and treatment planning. While manual landmarking has traditionally been the gold standard, it is labour-intensive and prone to variability. Objective This study presents a framework for automated landm...

Objective Assess the relationship between static and dynamic facial asymmetry in unilateral cleft lip and palate during maximum smile. Design Retrospective cross-sectional study. Setting Multidisciplinary dentofacial planning clinic. Participants Thirty-one surgically managed non-syndromic unilateral cleft lip and palate patients between the age...

Congenital Zika syndrome (CZS) has been identified a constellation of congenital anomalies caused by Zika Virus (ZKV) infection during pregnancy. The infection with ZKV could lead to microcephaly of the fetus due to a severe decrease in brain volume and reduced brain growth. The preliminary screening of CZS is based on measuring head circumference;...

Objectives: Despite the limited validity of the Sunnybrook grading index, it is routinely used for the clinical evaluation of facial palsy. This study aimed to assess the dynamic asymmetry in unilateral facial palsy and mathematically validate a modified version of the Sunnybrook facial grading system. Methods: The Sunnybrook facial grading system...

Background: 3D facial landmarking is becoming a fundamental part of clinical and biological applications. Manual landmarking is time consuming and prone to cumulative errors, so attempts have been made to automate 3D facial landmarking. However, data in the literature are sparse. Objectives: The objectives of this study are to investigate curren...

The digital articulation of dental models is gradually replacing the conventional physical approach for occlusal prediction planning. This study was performed to compare the accuracy and reproducibility of free-hand articulation of two groups of digital and physical dental models, 12 Class I (group 1) and 12 Class III (group 2). The models were sca...

Facial paralysis is a loss of facial movement due to nerve damage. It is essential for clinicians to diagnose the severity of the facial paralysis to treat patients, assess progresses and evaluate outcomes. Subjective assessments are common in clinical practices but have their limitations regarding the intra-observer and inter-observer reproducibil...

Background: This study was carried out in response to the Zika virus epidemic, which constituted a public health emergency, and to the 2019 WHO calling for strengthened surveillance for the early detection of related microcephaly. The main aim of the study was to phenotype the craniofacial morphology of microcephaly using a novel approach and new m...

Objective To validate a newly developed method for capturing 3-dimensional (3D) images of the nasolabial region for assessing upper lip scarring and asymmetry in surgically managed unilateral cleft lip and palate (UCLP) cases. Design Validation study, single cohort. Materials and Methods Eighteen surgically managed UCLP cases were recruited, the...

Objective Assess facial asymmetry during maximum smile in patients with surgically managed unilateral cleft lip and palate (UCLP), using a dynamic 3-dimensional (3D) imaging (4-dimensional) system. Design Prospective 2 cohort comparative study. Methods Twenty-five surgically managed UCLP cases and 75 controls at 8 to 10 years of age were recruite...

Little is known about why and how biomechanics govern the hypothesis that three-Lag-Screw (3LS) fixation is a preferred therapeutic technique. A series models of surgical internal-fixation for femoral neck fractures of Pauwells-II will be constructed by an innovative approach of finite element so as to determine the most stable fixation by comparis...

Purpose A series models of surgical internal fixation for femoral neck fracture of Pauwels II will be constructed by an innovative approach of finite element so as to determine the most stable fixation by comparison of their biomechanical performance. Method Seventeen specimens of proximal femurs scanned by computed tomography in Digital Imaging a...

Background: Little is known about how biomechanics govern the five fixtures such as DHS, MLS, DHS + LS, LP, and HA are accepted as common therapeutic techniques. Aims and objectives: A series of numerical models for a femoral neck fracture of Pauwels-I will be constructed by innovative approach of finite element in order to determine the most op...

Aim To evaluate the impact of facial expression on the asymmetry of surgically managed UCLP cases. Materials and methods The study was carried out on 13 four year old children. Facial images were captured at rest and at maximum smile using stereophotogrammetry. A generic mesh, which is a mathematical facial mask consisting of a fixed number of ind...

Objective: Longitudinal evaluation of asymmetry of the surgically managed unilateral cleft lip and palate (UCLP) to assess the impact of facial growth on facial appearance. Design: Prospective study. Setting: Glasgow Dental Hospital and School, University of Glasgow, United Kingdom Patients: Fifteen UCLP infants. Method: The 3-D facial image...

This study was carried out on 26 unilateral cleft lip and palate (UCLP) cases with mean age 3.6 ± 0.7 months.3D facial images were captured for each infant 2–3 days before the repair of cleft lip and at 4 months following surgery at a mean age of 8.2 ± 1.8 months, using a stereophotogrammetry imaging system. An iterative closest point (ICP) algorit...

Purpose: Cone-beam computed tomography (CBCT) does not record dental morphology accurately because of the scattering produced by metallic restorations and the reported magnification. The aim of this study was the development and evaluation of a new method for the replacement of the distorted dentition of CBCT scans with a 3-dimensional (3D) dental...

This study was performed to compare soft tissue changes in response to mandibular and bimaxillary advancement osteotomy. Preoperative and postoperative cone beam computed tomography scans of 24 cases were analysed: 12 underwent bimaxillary advancement and 12 underwent mandibular advancement. The skeletal surgical movements were measured and soft ti...

The aim of this study was to assess the reproducibility of non-verbal facial expressions in unilateral facial paralysis using dynamic four-dimensional (4D) imaging. The Di4D system was used to record five facial expressions of 20 adult patients. The system captured 60 three-dimensional (3D) images per second; each facial expression took 3-4seconds...

This study was performed to assess facial asymmetry in patients with unilateral cleft lip and palate (UCLP) before and after primary lip repair. Three-dimensional facial images of 30 UCLP cases (mean age 3.7. ±. 0.8. months) captured 1-2. days before surgery and 4 months after surgery using stereophotogrammetry were analysed. A generic mesh - a mat...

Abstract Background There is no universal hip implant suitably fills all femoral types, whether prostheses of porous short-stem suitable for Hip Arthroplasty is to be measured scientifically. Methods Ten specimens of femurs scanned by CT were input onto Mimics to rebuild 3D models; their *stl format dataset were imported into Geomagic-Studio for si...

The accuracy of three-dimensional (3D) predictions of soft tissue changes in the surgical correction of facial asymmetry was evaluated in this study. Preoperative (T1) and 6–12-month postoperative (T2) cone beam computed tomography scans of 13 patients were studied. All patients underwent surgical correction of facial asymmetry as part of a multidi...

Objective: To clinically monitor the progression of tooth wear over a period of one year in a cohort of referred tooth wear patients through the use of a CAD/CAD scanner and a standardised scanning/ assessment methodology. Methods: Polyether impressions were made of 11 participants (130 teeth) at baseline and one year. Impressions were poured in Ty...

This paper presents a system for positioning markers and tracking the pose of a rigid object with 6 degrees of freedom in real-time using 3D digital image correlation, with two examples for medical imaging applications. Traditional DIC method was improved to meet the requirements of the real-time by simplifying the computations of integral pixel se...

Aims: To detail and assess the capability of a novel methodology to 3D-quantify tooth wear progression in-vivo in a patient over a period of 12-months. Materials and methods: A calibrated stainless steel model (SSM) was used to identify the accuracy of the scanning system through assessing the accuracy and precision of the contact scanner and the...

‘Sur-face’ is an interactive mobile app illustrating different orthognathic surgeries and their potential complications. This study aimed to evaluate the efficacy of Sur-face by comparing two methods of delivering patient information on orthognathic surgeries and their related potential complications: a mobile app with interactive three-dimensional...

We describe the comprehensive 3-dimensional analysis of facial changes after Le Fort I osteotomy and introduce a new tool for anthropometric analysis of the face. We studied the cone-beam computed tomograms of 33 patients taken one month before and 6-12 months after Le Fort I maxillary advancement with or without posterior vertical impaction. Use o...

Objective: To systematically review the literature investigating the socioeconomic status (SES) as a potential risk factor of tooth wear in children, adolescents, and adults. Methods and Materials: PubMed, MEDLINE (Ovid), and Web of Science databases were screened for studies from 1990 to 2015. Cross-referencing was used to further identify article...

Objective: The aim of this study was to investigate correlations among the size, volume, and symmetry of the female breast after reconstruction based on previously published data. Methods: The centroid, namely the geometric center of a three-dimensional (3D) breast-landmark-based configuration, was used to calculate the size of the breast. The surf...

Purpose: Three dimensional analysis of the face is required for the assessment of complex changes following surgery, pathological conditions and to monitor facial growth. The most suitable method may be "dense surface correspondence". Materials and methods: This method utilizes a generic facial mesh and "conformation process" to establish anatom...

Aim; This study was carried out to provide a comprehensive description of facial changes following Le Fort I osteotomy and introducing a novel tool for facial anthropometric analysis. Materials & methods; This study was carried out on 33 patients who had had Le Fort I maxillary advancement with or without posterior vertical impaction. The investiga...

Purpose. Optical coherence tomography (OCT) is a novel light-based intravascular imaging method with potential utility for quantifying vascular disease and the effect of therapy. OCT has been used to image vein grafts and neointima in clinical research studies but validity of OCT for vein graft imaging is limited by depth of field and tissue penetr...

In order to detect findings of multiple clues from both CT and MR for early diagnostics, this study addresses to investigate a registration scheme for two-dimensional (2D) hybrid based on characteristic localization to achieve 3D-fusion from the images of CT and MR as a whole. A cubic oriented proposal of “9-point and 3-plane” for coregistration de...

Background and purpose: There is limited literature discussing the three dimnesional (3D) impact of rapid maxillary expansion (RME) on upper airway. The purpose of this prospective Cone Beam Computerised Tomography (CBCT) based study is to assess the immediate 3D effects and to correlate the volumteric changes in the upper naspharyngeal airway spa...

The limitations of the current methods of quantifying the surgical movements of facial bones inspired this study. The aim of this study was the assessment of the accuracy and reproduc-ibility of directly landmarking of 3D DICOM images (Digital Imaging and Communications in Medicine) to quantify the changes in the jaw bones following surgery. The st...

A multi-view three-dimensional stereophotogrammetry system was developed to capture 3D shape of breasts for breast cancer patients. The patients had received immediate unilateral breast reconstruction after mastectomy by the extended latissimus dorsi flap and without contralateral surgery. In order to capture the whole breast shape including the in...

The literature discussing the impact of a single Le Fort I osteotomy on nasopharyngeal airways is limited. This study assessed the volumetric changes in the nasopharyngeal airway after a single Le Fort I osteotomy and explored the correlation between these changes and 3-dimensional surgical movements of the upper jaw. This retrospective study was c...

The aim of this pilot study was to evaluate the impact of orthognathic surgical correction of facial asymmetry and maxillary hypoplasia on the magnitude and pattern of facial expressions. This study was carried out on 2 cohorts of patients: in group 1, 10 patients had surgical correction of facial asymmetry; in group 2, 13 patients had Le Fort I os...

A Novel Tooth Wear Index based-on in-vivo 3D Scanning Analysis Objective: to develop a tooth wear index capable of objectively classifying and quantifying the progression of tooth wear using accurate 3D scanning data of tooth wear in patients. Materials and methods: a 3D tooth wear scanning protocol, aimed at in-vivo monitoring of tooth wear pro...

Objective: To evaluate the reproducibility of three nonverbal facial expressions using a three-dimensional motion capture system. Design: Prospective, cross-sectional, controlled study. Setting: Glasgow Dental Hospital and School, University of Glasgow, United Kingdom. Patients and participants: Thirty-two subjects, 16 males and 16 females....

The aim of this presentation is the explanation of a mathematical analysis of a landmark-based procrustes calculation. The various components of breast symmetry and their impact on breast reconstruction have been examined. In an objective breast shape analysis asymmetries are quantified as a measure of the difference between a 3D landmark configura...

The aim of this pilot study was to evaluate the feasibility of measuring the change in magnitude, speed, and motion similarity of facial animations in head and neck oncology patients, before and after lip split mandibulotomy. Seven subjects (four males, three females) aged 42–80 years were recruited. The subjects were asked to perform four facial a...

Background: Rapid maxillary expansion (RME) is used to expand the narrow maxilla. Dental and skeletal affects have previously been reported but few studies have reported on the overlying soft tissue changes. This study reports on the immediate effects of RME on the naso-maxillary facial soft tissue using 3D stereophotogrammetry. Methods: Fourtee...

PURPOSE: Superimposition of two dimensional preoperative and postoperative facial images, including radiographs and photographs, are used to evaluate the surgical changes after orthognathic surgery. Recently, three dimensional (3D) imaging has been introduced allowing more accurate analysis of surgical changes. Surface based registration and voxel...

The transverse skeletal effects of rapid maxillary expansion (RME) have previously been assessed using cone-beam CT (CBCT). However, to date the majority of studies assess the changes based on two-dimensional slice images, which under utilises the three-dimensional (3D) data captured. This study optimizes the volumetric CBCT data by generating 3D r...

A method of producing a composite model consisting of a three-dimensional printed mandible bearing plaster teeth is presented. Printed models were obtained from cone beam computed tomograms (CBCT) of dry human mandibles. The plaster casts of the teeth were obtained from impressions of the teeth of the dry mandibles. The distorted teeth of the print...

Introduction: The percentage of adults presenting with severe tooth wear increases from 3% at the age of twenty to 17% at the age of seventy. Tooth wear has a measurable impact on patient satisfaction that affects patient appearance, pain levels, oral comfort, general performance, chewing and eating capacity. Currently, no tooth wear index is avail...

3D imaging of the breast has recently emerged as a new method for objective breast assessment. However in the ptotic breast shape, which is seen in the majority of cases, the sub-mammary fold remains obscured when the breast is captured in an upright body posture. A self-designed positioning frame for 3D breast capture was utilized as a safe positi...

During cone beam computed tomography (CBCT) scanning, intra-oral metallic objects may produce streak artefacts, which impair the occlusal surface of the teeth. This study aimed to determine the accuracy of replacement of the CBCT dentition with a more accurate dentition and to determine the clinical feasibility of the method. Impressions of the tee...

The motivation for orthognathic surgery is to improve facial appearance and quality of life. This study aimed to validate a three-dimensional (3D) orthognathic planning programme (Maxilim) for predicting soft tissue changes following Le Fort I advancements. Cone beam computed tomography (CBCT) scans were taken before surgery (T1) and at 6-12 months...

Background: To date breast assessment has been conducted mainly subjectively. However lately validated objective three-dimensional (3D) imaging was developed. The study aimed to assess breast reconstruction subjectively and objectively and conduct a comparison. Methods: In forty-four patients after immediate unilateral breast reconstruction with...

A new method for automatic tracking of facial landmarks in 3D motion captured images (4D). Int. Abstract. The aim of this study was to validate the automatic tracking of facial landmarks in 3D image sequences. 32 subjects (16 males and 16 females) aged 18– 35 years were recruited. 23 anthropometric landmarks were marked on the face of each subject...

The aim of this study was to evaluate the impact of simultaneous capture of the three-dimensional (3D) surface of the face and cone beam computed tomography (CBCT) scan of the skull on the accuracy of their registration and superimposition. 3D facial images were acquired in 14 patients using the Di3d (Dimensional Imaging, UK) imaging system and i-C...

The aim of this study was to validate the automatic tracking of facial landmarks in 3D image sequences. 32 subjects (16 males and 16 females) aged 18-35 years were recruited. 23 anthropometric landmarks were marked on the face of each subject with non-permanent ink using a 0.5mm pen. The subjects were asked to perform three facial animations (maxim...

Because there is no complete three-dimensional (3D) hybrid detector integrated PET+MRI internationally, this study aims to investigate a registration approach for a two-dimensional (2D) hybrid based on characteristic localization to achieve a 3D fusion from the images of PET and MRI as a whole. A cubic-oriented scheme of "9-point and 3-plane" for a...

Facial functional impairments develop from a variety of causes. In order to quantify the impairments of animations, the reproducibility of facial animations was investigated. In this paper, non-verbal facial animations of maximal smile, check puff and lip purse were captured by a video stereo photogrammetry system; and anatomical facial landmarks w...

Background: Errors derive from the variability seen in the repeat volume measurements for a particular individual. The aim of this study was to evaluate the variation and errors of a three-dimensional (3D) multiple stereo camera system for objective breast assessment. It was also investigated whether there was any correlation between these errors...

The latissimus dorsi muscle flap is a common method for the reconstruction of the breast following mastectomy. The study aimed to assess the quality of this reconstruction using a three-dimensional (3D) imaging method. The null hypothesis was that there was no difference in volume between the reconstructed breast and the opposite side. This study w...

To investigate a registration approach for 2-dimension (2D) based on characteristic localization to achieve 3-dimension (3D) fusion from images of PET, CT and MR one by one. A cubic oriented scheme of"9-point & 3-plane" for co-registration design was verified to be geometrically practical. After acquisiting DICOM data of PET/CT/MR (directed by radi...

The aim of this study was to evaluate the validity of a three-dimensional (3D) multiple stereo camera system for objective breast assessment. A multiple stereo camera system, which consisted of four pods and eight cameras, two cameras on each pod, developed by Glasgow University, was used. Nine specially shaped plaster breast models were captured o...

This paper presents a fully automatic approach to fitting a generic facial model to detailed range scans of human faces to reconstruct 3D facial models and textures with no manual intervention (such as specifying landmarks). A Scaling Iterative Closest Points (SICP) algorithm is introduced to compute the optimal rigid registrations between the gene...

This paper presents an automatic framework for face model and texture reconstruc-tion, facial expression transferring, and face tracking from 3D and 4D range scans. Tak-ing the scale transformation into consideration, an extension of the iterative closest points (ICP) algorithm is introduced to solve the problem of registering a generic face model...

We present a self-correction approach to improving the 3D reconstruction of a multi-view 3D photogrammetry system. The self-correction approach has been able to repair the reconstructed 3D surface damaged by depth discontinuities. Due to self-occlusion, multi-view range images have to be acquired and integrated into a watertight non-redundant mesh...

This paper presents an automated approach to transferring facial expressions from a generic facial model onto various individual facial models without requiring any prior correspondences and manual interventions during the transferring process. This approach automatically detects the corresponding feature landmarks between models, and establishes t...

The displacement and strain fields of the PLC band are quantitatively measured using a technique based on high-speed digital photography and digital speckle correlation (DSC) method. The results show the nucleation process of a type B band within a few milliseconds. Even the type A band intermittently propagates with steps smaller than the band wid...

The V-Man project has developed an intuitive authoring and intelligent system to create, animate, control and interact in real-time with a new generation of 3D virtual characters: The V-Men. It combines several innovative algorithms coming from Virtual Reality, Physical Simulation, Computer Vision, Robotics and Artificial Intelligence. Given a high...

In this paper, we present a method for constructing dense correspondences between 3D open surfaces that is sufficiently accurate to permit clinical analysis of 3D facial morphology. Constructing dense correspondences between 3D models representing facial surface anatomy is a natural extension of landmark-based methods for analysing facial shape or...

A photogrammetric stereo imaging system was used to capture 3-D models of live pigs, and quantitative shape measurements were extracted from cross sections of the models. Stereo images were captured of 32 pigs, divided into high-lysine and low-lysine diet groups, and 3-D models were built from the images. Each pig was imaged once per week for 14 we...

We develop a 3D thermography imaging standardization technique to allow quantitative data analysis. Medical Digital Infrared Thermal Imaging is very sensitive and reliable mean of graphically mapping and display skin surface temperature. It allows doctors to visualise in colour and quantify temperature changes in skin surface. The spectrum of colou...

A mesh conformation approach that makes use of deformable generic meshes has been applied to establishing correspondences between 3D shapes with missing data. Given a group of shapes with correspondences, we can build up a statistical shape model by applying principal component analysis (PCA). The conformation at first globally maps the generic mes...

A novel method for integrating multiple range images in a multi-view stereo imaging system is presented here. Due to self-occlusion an individual range image provides only a partial model of an object surface. Therefore multiple range images from differing viewpoints must be captured and merged to extend the surface area that can be captured. In ou...

A stereo imaging system with six high-resolution cameras (3032 × 2028 pixels) and three flash units was developed to capture the 3D shapes of live pigs. The cameras were arranged in three stereo pods, which captured the side, top and rear views of each pig. The image resolution was 0.4 mm per pixel on the surface of the pig.The system was used to c...

We have succeeded in capturing porcine 3D surface anatomy in vivo by developing a high-resolution stereo imaging system. The system achieved accurate 3D shape recovery by matching stereo pair images containing only natural surface textures at high (image) resolution. The 3D imaging system presented for pig shape capture is based on photogrammetry a...

In this paper we present a new workflow allowing the creation of 3D characters in an automated way that does not require the expertise of an animator. This workflow is based of the acquisition of real human data captured by 3D body scanners, which is them processed to generate firstly animatable body meshes, secondly skinned body meshes and finally...

In this paper we present a new workflow allowing the creation of 3D characters in an automated way that does not require the expertise of an animator.

The advent of photogrammetry-based 3D data collection techniques means that the highly accurate 3D surface of a specific person can now be collected in a matter of milliseconds. Existing human animation models provide excellent tools to control articulated motion and body surface deformations according to body postures, but modelling a specific ind...

Realistic human figure animation has to take account of the deformations of body, hands and face as well as the articulate motion. We proposed to make best utility of high quality 3D human body scans for human body animation by combining it with available human animation models, such that a specific person can be animated in the virtual world. The...

This paper describes a hybrid least squares stereo matching and feature detection approach for the accurate metric recovery of 3-D facial shape and shape change. We have incorporated an active shape model to enable a priori image segmentation, facilitate adaptive window stereo matching and to locate seed point correspondences on which full field di...