Статті в журналах: "3D soft tissue prediction"

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Olivetti, Elena Carlotta, Sara Nicotera, Federica Marcolin, Enrico Vezzetti, Jacqueline P. A. Sotong, Emanuele Zavattero, and Guglielmo Ramieri. "3D Soft-Tissue Prediction Methodologies for Orthognathic Surgery—A Literature Review." Applied Sciences 9, no. 21 (October 26, 2019): 4550. http://dx.doi.org/10.3390/app9214550.

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Three-dimensional technologies have had a wide diffusion in several fields of application throughout the last decades; medicine is no exception and the interest in their introduction in clinical applications has grown with the refinement of such technologies. We focus on the application of 3D methodologies in maxillofacial surgery, where they can give concrete support in surgical planning and in the prediction of involuntary facial soft-tissue changes after planned bony repositioning. The purpose of this literature review is to offer a panorama of the existing prediction methods and software with a comparison of their reliability and to propose a series of still pending issues. Various software are available for surgical planning and for the prediction of tissue displacements, but their reliability is still an unknown variable in respect of the accuracy needed by surgeons. Maxilim, Dolphin and other common planning software provide a realistic result, but with some inaccuracies in specific areas of the face; it also is not totally clear how the prediction is obtained by the software and what is the theoretical model they are based on.

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LI, SUJIAO, ZHENGXIANG ZHANG, and JUE WANG. "A NEW CUSTOM-CONTOURED CUSHION SYSTEM BASED ON FINITE ELEMENT MODELING PREDICTION." Journal of Mechanics in Medicine and Biology 13, no. 04 (July 7, 2013): 1350051. http://dx.doi.org/10.1142/s0219519413500516.

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High internal stress in the deep tissues adjacent to bony prominences can cause deep tissue injuries. Therefore, internal stress in the soft tissue should be considered when the performance of anti-decubitus cushions is evaluated during cushion design. This paper reports on a custom-contoured cushion (CCC) system incorporated with a three-dimensional (3D) slice subject-specific finite element (FE) model to investigate the internal stress distribution in the soft tissues. This stress distribution was used to transform the interface pressure into the carving depth of the fabricated cushions based on the biomechanical characteristics of the cushion materials. The internal stress in the soft tissues was investigated using an FE model of buttocks and cushion made from three cushion materials. The cushion design was optimized according to the properties of the material. The simulated interface stress between the buttocks and the cushion (18 kPa) was consistent with the measured interface pressure of the CCC (17.1 kPa). The 3D FE model predicted the internal stress and displacement of the soft tissues and cushion. Additionally, it efficiently optimized the selection of cushion material. Fifty subjects (25 subjects with spinal cord injuries (SCI) and 25 healthy subjects) were recruited to investigate the interface pressure and perform subjective comfort evaluation. The CCC decreased the interface pressure under the buttocks and simultaneously increased the subjective comfort and stability. The effectiveness of the cushion materials was predicted by the CCC system, which also validated the clinical performance of decreasing interface pressure.

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Lai, Hsin-Chih, Rafael Denadai, Cheng-Ting Ho, Hsiu-Hsia Lin, and Lun-Jou Lo. "Effect of Le Fort I Maxillary Advancement and Clockwise Rotation on the Anteromedial Cheek Soft Tissue Change in Patients with Skeletal Class III Pattern and Midface Deficiency: A 3D Imaging-Based Prediction Study." Journal of Clinical Medicine 9, no. 1 (January 18, 2020): 262. http://dx.doi.org/10.3390/jcm9010262.

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Patients with a skeletal Class III deformity may present with a concave contour of the anteromedial cheek region. Le Fort I maxillary advancement and rotational movements correct the problem but information on the impact on the anteromedial cheek soft tissue change has been insufficient to date. This three-dimensional (3D) imaging-assisted study assessed the effect of surgical maxillary advancement and clockwise rotational movements on the anteromedial cheek soft tissue change. Two-week preoperative and 6-month postoperative cone-beam computed tomography scans were obtained from 48 consecutive patients who received 3D-guided two-jaw orthognathic surgery for the correction of Class III malocclusion associated with a midface deficiency and concave facial profile. Postoperative 3D facial bone and soft tissue models were superimposed on the corresponding preoperative models. The region of interest at the anteromedial cheek area was defined. The 3D cheek volumetric change (mm3; postoperative minus preoperative models) and the preoperative surface area (mm2) were computed to estimate the average sagittal movement (mm). The 3D cheek mass position from orthognathic surgery-treated patients was compared with published 3D normative data. Surgical maxillary advancement (all p < 0.001) and maxillary rotation (all p < 0.006) had a significant effect on the 3D anteromedial cheek soft tissue change. In total, 78.9%, 78.8%, and 78.8% of the variation in the cheek soft tissue sagittal movement was explained by the variation in the maxillary advancement and rotation movements for the right, left, and total cheek regions, respectively. The multiple linear regression models defined ratio values (relationship) between the 3D cheek soft tissue sagittal movement and maxillary bone advancement and rotational movements of 0.627 and 0.070, respectively. Maxillary advancements of 3–4 mm and >4 mm resulted in a 3D cheek mass position (1.91 ± 0.53 mm and 2.36 ± 0.72 mm, respectively) similar (all p > 0.05) to the 3D norm value (2.15 ± 1.2 mm). This study showed that both Le Fort I maxillary advancement and rotational movements affect the anteromedial cheek soft tissue change, with the maxillary advancement movement presenting a larger effect on the cheek soft tissue movement than the maxillary rotational movement. These findings can be applied in future multidisciplinary-based decision-making processes for planning and executing orthognathic surgery.

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Awad, Daniel, Siegmar Reinert, and Susanne Kluba. "Accuracy of Three-Dimensional Soft-Tissue Prediction Considering the Facial Aesthetic Units Using a Virtual Planning System in Orthognathic Surgery." Journal of Personalized Medicine 12, no. 9 (August 25, 2022): 1379. http://dx.doi.org/10.3390/jpm12091379.

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Virtual surgical planning (VSP) is commonly used in orthognathic surgery. A precise soft-tissue predictability would be a helpful tool, for determining the correct displacement distances of the maxilla and mandible. This study aims to evaluate the soft-tissue predictability of the VSP software IPS CaseDesigner® (KLS Martin Group, Tuttlingen, Germany). Twenty patients were treated with bimaxillary surgery and were included in the study. The soft-tissue simulation, done by the VSP was exported as STL files in the engineering software Geomagic Control XTM (3D systems, RockHill, SC, USA). Four months after surgery, a 3D face scan of every patient was performed and compared to the preoperative simulation. The quality of the soft-tissue simulation was validated with the help of a distance map. This distance map was calculated using the inter-surface distance algorithm between the preoperative simulation of the soft-tissue and the actual scan of the postoperative soft-tissue surface. The prediction of the cranial parts of the face (upper cheek, nose, upper lip) was more precise than the prediction of the lower areas (lower cheek, lower lip, chin). The percentage of correctly predicted soft-tissue for the face in total reached values from 69.4% to 96.0%. The VSP system IPS CaseDesigner® (KLS Martin Group; Tuttlingen, Germany) predicts the patient’s post-surgical soft-tissue accurately. Still, this simulation has to be seen as an approximation, especially for the lower part of the face, and continuous improvement of the underlying algorithm is needed for further development.

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Wang, Li Ping, Yi Guo, Xue Ling Jiang, Jiang Hui Dong, and Long Wang. "Study on Three-Dimensional Surgical Simulation and Face Prediction of the Individualized Maxillofacial Soft and Hard Tissue." Applied Mechanics and Materials 543-547 (March 2014): 1892–95. http://dx.doi.org/10.4028/www.scientific.net/amm.543-547.1892.

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Three-dimensional 3D modeling, surgery simulation and face prediction of the maxillofacial soft and hard tissue has a great significance for the study of facial growth and development, diagnosis and treatment of facial deformity and postoperative face prediction and treatment evaluation. Based on maxillofacial 3D modeling and measurement analysis, real-time variable model is set up. In virtual environment, image feedback, force and tactile perception in combined together surgical simulation. Furthermore, the system of surgical prediction and postoperative results display is proposed, which has great value and clinical significance.

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Abdullah, Johari Yap, Cicero Moraes, Mokhtar Saidin, Zainul Ahmad Rajion, Helmi Hadi, Shaiful Shahidan, and Jafri Malin Abdullah. "Forensic Facial Approximation of 5000-Year-Old Female Skull from Shell Midden in Guar Kepah, Malaysia." Applied Sciences 12, no. 15 (August 5, 2022): 7871. http://dx.doi.org/10.3390/app12157871.

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Forensic facial approximation was applied to a 5000-year-old female skull from a shell midden in Guar Kepah, Malaysia. The skull was scanned using a computed tomography (CT) scanner in the Radiology Department of the Hospital Universiti Sains Malaysia using a Light Speed Plus scanner with a 1 mm section thickness in spiral mode and a 512 × 512 matrix. The resulting images were stored in Digital Imaging and Communications in Medicine (DICOM) format. A three-dimensional (3D) model of the skull was obtained from the CT scan data using Blender’s 3D modelling and animation software. After the skull was reconstructed, it was placed on the Frankfurt plane, and soft tissue thickness markers were placed based on 34 Malay CT scan data of the nose and lips. The technique based on facial approximation by data extracted from facial measurements of living individuals showed greater anatomical coherence when combined with anatomical deformation. The facial approximation in this study will pave the way towards understanding face prediction based on skull structures, soft tissue prediction rules, and soft tissue thickness descriptors.

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Hakonen, Bodil, Linnea K. Lönnberg, Eva Larkö, and Kristina Blom. "A Novel Qualitative and Quantitative Biofilm Assay Based on 3D Soft Tissue." International Journal of Biomaterials 2014 (2014): 1–5. http://dx.doi.org/10.1155/2014/768136.

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The lack of predictablein vitromethods to analyze antimicrobial activity could play a role in the development of resistance to antibiotics. Current used methods analyze planktonic cells but for the method to be clinically relevant, biofilm inin vivolike conditions ought to be studied. Hence, our group has developed a qualitative and quantitative method within vivolike 3D tissue for prediction of antimicrobial activity in reality. Devices (wound dressings) were applied on top ofPseudomonas aeruginosainoculated Muller-Hinton (MH) agar or 3D synthetic soft tissues (SST) and incubated for 24 hours. The antibacterial activity was then analyzed visually and by viable counts. On MH agar two out of three silver containing devices showed zone of inhibitions (ZOI) and on SST, ZOI were detected for all three. Corroborating results were found upon evaluating the bacterial load in SST and shown to be silver concentration dependent. In conclusion, a novel method was developed combining visual rapid screening and quantitative evaluation of the antimicrobial activity in both tissue and devices. It uses tissue allowing biofilm formation thus mimicking reality closely. These conditions are essential in order to predict antimicrobial activity of medical devices in the task to prevent device related infections.

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Garcia Flores, Jose, Ritu Mogra, Monica Sadowski, and Jon Hyett. "Prediction of Birth Weight and Neonatal Adiposity Using Ultrasound Assessment of Soft Tissue Parameters in Addition to Two-Dimensional Conventional Biometry." Fetal Diagnosis and Therapy 48, no. 3 (2021): 201–8. http://dx.doi.org/10.1159/000510637.

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Introduction: We aim to evaluate the supplementary predictive value of soft tissue markers, including fetal limb volumes, for fetal birth weight and fat tissue weight. Methods: This is a prospective study of 60 patients undergoing term induction of labor. Ultrasound was performed 48 h before birth, and 2D sonographic measurements, subcutaneous tissue thickness, and 3D fetal limb volumes were taken. Birth weight and neonatal fat weight were assessed by plethysmography. Clinical data were collected. The relation between ultrasound and neonatal outcomes was assessed by univariate and multivariate predictive models. The estimated and actual birth weights were compared applying different published formulas, and systematic and random error were collected and compared. Results: 3D fetal limb volumes showed a strong relation to birth weight, absolute weight, and relative fat weight. The Lee 6 formula performed better than either Hadlock 3 or Lee 3 with the lowest random error. Fractional limb volumes involve a highly reproducible technique, with excellent correlation (intra-class coefficient >0.90) for both inter- and intra-observer reliability. The prevalence of estimated EFW measures within 10% error from the actual birth weight was 71.7% with the Hadlock 3 model and 95.0% with the Lee 6 model (p = 0.09). Conclusion: Late assessment of 3D fetal limb volume in upper and lower extremities is not only useful for accurately predicting birth weight but is a useful marker for prediction of birth fat tissue weight.

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Jaeger, Rudolf, Julia Glöggler, To Mai Pham, Falko Schmidt, Elena Schramm, Alexander Schramm, and Bernd G. Lapatki. "Experimental and numerical evaluation of simulated dental arch expansion during orthodontic therapy." Current Directions in Biomedical Engineering 8, no. 1 (July 1, 2022): 85–88. http://dx.doi.org/10.1515/cdbme-2022-0022.

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Abstract In this publication, methods are presented to improve predictions of perioral soft-tissue changes following the expansion of the dental arches during orthodontic therapy. Acrylic veneers with different thicknesses were reversibly attached to the buccal surfaces of the upper and lower incisors to simulate their protrusion. The resulting morphological changes of the perioral soft-tissue surface were determined by 3D face scans. Experimentally-determined 3D soft-tissue changes are compared to numerical predictions using detailed finite-element (FE) models of the face of two individuals differing in the body mass index (BMI). The results suggest that common estimates of material constants used by the detailed and individualized FE models might be sufficient to explain absolute soft-tissue displacements although differences occurred between experimental and modeling results regarding the directions of displacements. The aim of this investigation is to create predictions of post-treatment appearance that are helpful for therapy planning.

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Xia, James, Nabil Samman, Richie W. K. Yeung, Dongfeng Wang, Steve G. F. Shen, Horace H. S. Ip, and Henk Tideman. "Computer-assisted three-dimensional surgical planning and simulation. 3D soft tissue planning and prediction." International Journal of Oral and Maxillofacial Surgery 29, no. 4 (August 2000): 250–58. http://dx.doi.org/10.1034/j.1399-0020.2000.290404.x.

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Shobair, Nehal, Mohammed Diaa, Ahmed Barakat, and Amr Ghanem. "The Prediction Accuracy of Dolphin 3D Software for Facial Soft Tissue Changes After Bimaxillary Orthognathic Surgery." Ain Shams Dental Journal 23, no. 3 (September 1, 2021): 55–61. http://dx.doi.org/10.21608/asdj.2022.103220.1080.

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Tiwari, Rahul, P. Srinivas Chakravarthi, Vivekanand S. Kattimani, and Krishna Prasad Lingamaneni. "A Perioral Soft Tissue evaluation after Orthognathic Surgery Using Three-Dimensional Computed Tomography Scan." Open Dentistry Journal 12, no. 1 (April 30, 2018): 366–76. http://dx.doi.org/10.2174/1874210601812010366.

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Background: Facial appearance is an important factor, affects social and psychological well-being. The ideal positioning of jaws and soft tissues is crucial during orthognathic surgery for a better outcome, but the response of facial soft tissues does not always reflect the exact movements of the underlying jaws in 1:1 ratio. So, soft tissue changes following orthognathic surgery require utmost attention during surgical correction to make successful treatment. Aims and Objectives: Evaluation of perioral soft tissue changes after orthognathic surgical procedures. The objectives of the study were to assess and compare pre and post-operative perioral soft tissue changes of lip width, nasolabial and mentolabial angle using Three Dimensional Computed Tomography scan (3DCT). Patient and Methods: The study involved ten patients for evaluation requiring orthognathic surgical procedures (maxillary or mandibular anteroposterior excess or deficiency, transverse deformities, vertical maxillary excess and facial asymmetry) presented to the department of oral and maxillofacial surgery during 2014-2016. Pre and post-operative 3DCT scan were taken after 12 months using iCT 256 slice whole body CT scanner and evaluated for changes using Dicom PMS D view. Results: Significant changes were observed in nasolabial angle after maxillary advancement (1.81°) and maxillary setback procedure (2.73°). The mentolabial angle was significantly increased with mandibular setback procedures (3.27°). Mandibular advancement procedures showed both increase (3.6°) and decrease (7.6°) in mentolabial angle. Conclusion: 3DCT showed a significant difference in perioral soft tissue changes in nasolabial and mentolabial angle but no significant change was observed in lip width. 3DCT is a reliable tool for 3D assessment. The conventional thought of changes in Nasolabial angle after surgery is changing due to the underlying factors which should be considered for prediction.

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LI, SUJIAO, MIN YIN, LIN GAO, SHUN QI, and JUE WANG. "FINITE ELEMENT PREDICTION OF SUB-DERMAL TISSUE STRESSES OF THE BUTTOCKS DURING WHEELCHAIR PROPULSION." Journal of Mechanics in Medicine and Biology 16, no. 04 (June 2016): 1650058. http://dx.doi.org/10.1142/s0219519416500585.

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Pressure ulcers, involving sub-dermal tissue damage and originating in deep tissue injury (DTI), have attracted much attention of physicians and researchers for three decades. Finite element (FE) model is a very efficient tool to investigate internal stresses and strains in human body that induce pressure ulcers. However, there was scarce report available to explore stresses distribution in human buttocks during manual wheelchair propulsion. A three-dimensional (3D) comprehensive FE model, incorporating ischial tuberosities (ITs), muscle, fat, and custom-contoured cushion (CCC), was developed to investigate internal stress distribution in soft tissue of the buttocks. Based on the FE model, pressure distribution under ITs in static sitting and during different wheelchair propulsions is studied. Internal stresses in fat and muscle were about three times and five times higher than that on cushion surface in terms of static sitting and wheelchair propulsion. All peak pressures under wheelchair propulsion were higher than those of static sitting, and peak pressures went on increasing with increase of wheelchair movement speed. This method based on the comprehensive FE model allowed for the optimization of wheelchair seat cushion design.

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Nadjmi, N., W. Mollemans, F. Schutyser, and P. Suetens. "P.162 3D soft tissue predictions for a computer-aided maxillofacial surgery planning system." Journal of Cranio-Maxillofacial Surgery 34 (September 2006): 173–74. http://dx.doi.org/10.1016/s1010-5182(06)60670-7.

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Resnick, C. M., R. R. Dang, S. J. Glick, and B. L. Padwa. "Accuracy of three-dimensional soft tissue prediction for Le Fort I osteotomy using Dolphin 3D software: a pilot study." International Journal of Oral and Maxillofacial Surgery 46, no. 3 (March 2017): 289–95. http://dx.doi.org/10.1016/j.ijom.2016.10.016.

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Thurzo, Andrej, Helena Svobodová Kosnáčová, Veronika Kurilová, Silvester Kosmeľ, Radoslav Beňuš, Norbert Moravanský, Peter Kováč, Kristína Mikuš Kuracinová, Michal Palkovič, and Ivan Varga. "Use of Advanced Artificial Intelligence in Forensic Medicine, Forensic Anthropology and Clinical Anatomy." Healthcare 9, no. 11 (November 12, 2021): 1545. http://dx.doi.org/10.3390/healthcare9111545.

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Three-dimensional convolutional neural networks (3D CNN) of artificial intelligence (AI) are potent in image processing and recognition using deep learning to perform generative and descriptive tasks. Compared to its predecessor, the advantage of CNN is that it automatically detects the important features without any human supervision. 3D CNN is used to extract features in three dimensions where input is a 3D volume or a sequence of 2D pictures, e.g., slices in a cone-beam computer tomography scan (CBCT). The main aim was to bridge interdisciplinary cooperation between forensic medical experts and deep learning engineers, emphasizing activating clinical forensic experts in the field with possibly basic knowledge of advanced artificial intelligence techniques with interest in its implementation in their efforts to advance forensic research further. This paper introduces a novel workflow of 3D CNN analysis of full-head CBCT scans. Authors explore the current and design customized 3D CNN application methods for particular forensic research in five perspectives: (1) sex determination, (2) biological age estimation, (3) 3D cephalometric landmark annotation, (4) growth vectors prediction, (5) facial soft-tissue estimation from the skull and vice versa. In conclusion, 3D CNN application can be a watershed moment in forensic medicine, leading to unprecedented improvement of forensic analysis workflows based on 3D neural networks.

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Ardani, I. Gusti Aju Wahju, Floretta Charlene Dinata, and Ari Triwardhani. "The Importance of the Occlusal Plane in Predicting Better Facial Soft Tissue in Class II Malocclusion in Ethnic Javanese." European Journal of Dentistry 14, no. 03 (June 26, 2020): 429–34. http://dx.doi.org/10.1055/s-0040-1713331.

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Abstract Objectives Class II malocclusion is largely due to a retrognathic mandible. Mandibular rotation is closely related to changes in the occlusal plane during growth. The problems in the occlusal plane could cause disadvantages in the soft tissue profile in Class II malocclusion, presenting treatment challenges for an orthodontist. This study aimed to investigate the importance of the occlusal plane for a better soft tissue profile in Class II malocclusion for Javanese patients. Materials and Methods The total number of cephalogram softcopies of patients with skeletal Class II malocclusion were selected based on ANB values (> 4 degrees), no agenesis teeth except the third molar, and all permanent teeth. The cephalograms were calculated using digital tracing by Morpheus 3D imaging. The points and areas to be analyzed on the cephalogram were predetermined. The examination was performed in a span of 1 month and performed via a statistical test using Pearson’s test and multiple regression analysis (p < 0.05). Results There were significant correlation values between the angles produced by the occlusal plane to sella national, Frankfurt horizontal, mandibular plane, and Z-angle (p < 0.05). Conclusion Patients with skeletal Class II malocclusion have a significant correlation between the occlusal plane and the vertical plane, thereby affecting the shape of the soft tissue profile, which causes a facial imbalance. By improving mandibular movement, the soft tissue profile can also be corrected.

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Vale, Francisco, Jessica Scherzberg, João Cavaleiro, David Sanz, Francisco Caramelo, Luísa Maló, and João Pedro Marcelino. "3D virtual planning in orthognathic surgery and CAD/CAM surgical splints generation in one patient with craniofacial microsomia: a case report." Dental Press Journal of Orthodontics 21, no. 1 (February 2016): 89–100. http://dx.doi.org/10.1590/2177-6709.21.1.089-100.oar.

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Objective: In this case report, the feasibility and precision of tridimensional (3D) virtual planning in one patient with craniofacial microsomia is tested using Nemoceph 3D-OS software (Software Nemotec SL, Madrid, Spain) to predict postoperative outcomes on hard tissue and produce CAD/CAM (Computer Aided Design/Computer Aided Manufacturing) surgical splints. Methods: The clinical protocol consists of 3D data acquisition of the craniofacial complex by cone-beam computed tomography (CBCT) and surface scanning of the plaster dental casts. The ''virtual patient'' created underwent virtual surgery and a simulation of postoperative results on hard tissues. Surgical splints were manufactured using CAD/CAM technology in order to transfer the virtual surgical plan to the operating room. Intraoperatively, both CAD/CAM and conventional surgical splints are comparable. A second set of 3D images was obtained after surgery to acquire linear measurements and compare them with measurements obtained when predicting postoperative results virtually. Results: It was found a high similarity between both types of surgical splints with equal fitting on the dental arches. The linear measurements presented some discrepancies between the actual surgical outcomes and the predicted results from the 3D virtual simulation, but caution must be taken in the analysis of these results due to several variables. Conclusions: The reported case confirms the clinical feasibility of the described computer-assisted orthognathic surgical protocol. Further progress in the development of technologies for 3D image acquisition and improvements on software programs to simulate postoperative changes on soft tissue are required.

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Olivetti, Elena Carlotta, Federica Marcolin, Sandro Moos, Alberto Ferrando, Enrico Vezzetti, Umberto Autorino, Claudia Borbon, Emanuele Zavattero, Giovanni Gerbino, and Guglielmo Ramieri. "Three-Dimensional Evaluation of Soft Tissue Malar Modifications after Zygomatic Valgization Osteotomy via Geometrical Descriptors." Journal of Personalized Medicine 11, no. 3 (March 13, 2021): 205. http://dx.doi.org/10.3390/jpm11030205.

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Patients with severe facial deformities present serious dysfunctionalities along with an unsatisfactory aesthetic facial appearance. Several methods have been proposed to specifically plan the interventions on the patient’s needs, but none of these seem to achieve a sufficient level of accuracy in predicting the resulting facial appearance. In this context, a deep knowledge of what occurs in the face after bony movements in specific surgeries would give the possibility to develop more reliable systems. This study aims to propose a novel 3D approach for the evaluation of soft tissue zygomatic modifications after zygomatic osteotomy; geometrical descriptors usually involved in face analysis tasks, i.e., face recognition and facial expression recognition, are here applied to soft tissue malar region to detect changes in surface shape. As ground truth for zygomatic changes, a zygomatic openness angular measure is adopted. The results show a high sensibility of geometrical descriptors in detecting shape modification of the facial surface, outperforming the results obtained from the angular evaluation.

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Mahmoud, Menna, Mohammed Khashaba, and Nader Elbokle. "Reliability of Using Virtual Planning Software in Prediction of 3D Volumetric Soft Tissue Changes After Genioplasty in Patients With Chin Deformity (Case Series)." Egyptian Dental Journal 68, no. 2 (April 1, 2022): 1389–400. http://dx.doi.org/10.21608/edj.2022.110474.1960.

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Hu, Yongsheng, and Liyi Zhang. "Pseudo CT Generation Based on 3D Group Feature Extraction and Alternative Regression Forest for MRI-Only Radiotherapy." International Journal of Pattern Recognition and Artificial Intelligence 32, no. 06 (February 21, 2018): 1855009. http://dx.doi.org/10.1142/s0218001418550091.

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In recent decades, magnetic resonance imaging (MRI) has attracted attention in radiation therapy as the only modality. This nontrivial task requires the application of pseudo computed tomography (PCT) generation methods. On the one hand, the electron density information provided by the CT scan is critical for calculating the 3D dose distribution of tissues. On the other hand, the bone image provided by the CT is precise enough for the construction of a radiograph. Lately, the use of MRI/CT has combined all of the soft tissue contrast merits which are contributed by the MRI and the virtue of CT imaging. However, owing to the unbalance of voxel-intensities in the MRI and CT scan, the MRI/CT workflow also has shortcomings. Inspired by the random forest-based PCT estimation, this paper investigated the potential of the 3D group feature as the input of the random forest regression, which is based on the 3D block-matching method, taking the correlated central voxel as the target. Four types of features including the voxel level, sub-regional level, whole cubic level with adaptive weighted conjunction and compressed level were introduced to attain the robust features. The group-based random forest regression was then utilized to obtain the approximated PCT only from corresponding MRI, and the feature is extracted from the 3D cubic MRI patches and mapped to the 3D cubic CT patch, which helps in decreasing the computation difficulty, representing the MR patches into an anatomical feature space. The alternative regression forest was used in solving the regression task for enhancing the prediction power compared with the random forest. The proposed method could efficiently capture the correlation that is observable between the CT as well as the MR images on the basis of the alternative random forest (ARF) with cubic features, and the experimental results show the performance and effectiveness of the proposed method compared with the recent learning-based and atlas-based (AB) methods

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Caggiari, Silvia, Bethany Keenan, Dan L. Bader, Mark N. Mavrogordato, Kathryn Rankin, Sam L. Evans, and Peter R. Worsley. "A combined imaging, deformation and registration methodology for predicting respirator fitting." PLOS ONE 17, no. 11 (November 11, 2022): e0277570. http://dx.doi.org/10.1371/journal.pone.0277570.

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N95/FFP3 respirators have been critical to protect healthcare workers and their patients from the transmission of COVID-19. However, these respirators are characterised by a limited range of size and geometry, which are often associated with fitting issues in particular sub-groups of gender and ethnicities. This study describes a novel methodology which combines magnetic resonance imaging (MRI) of a cohort of individuals (n = 8), with and without a respirator in-situ, and 3D registration algorithm which predicted the goodness of fit of the respirator. Sensitivity analysis was used to optimise a deformation value for the respirator-face interactions and corroborate with the soft tissue displacements estimated from the MRI images. An association between predicted respirator fitting and facial anthropometrics was then assessed for the cohort.

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Lee, Yong Jig, Dong Gil Han, Se Hun Kim, Jeong Su Shim, and Sung-Eun Kim. "Discrepancy of the location of depression on the soft tissue and the bone in isolated zygomatic arch fracture." Archives of Craniofacial Surgery 24, no. 1 (February 20, 2023): 18–23. http://dx.doi.org/10.7181/acfs.2023.00031.

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Background: When performing reduction of zygomatic arch fractures, locating the inward portion of the fracture can be difficult. Therefore, this study investigated the discrepancy between the locations of the depression on the soft tissue and bone and sought to identify how to determine the inward portion of the fracture on the patient’s face.Methods: We conducted a retrospective review of chart with isolated zygomatic arch fractures of type V in the Nam and Jung classification from March 2013 to February 2022. For consistent measurements, a reference point (RP), at the intersection between a vertical line passing through the end point of the root of the ear helix in the patient’s side-view photograph and a transverse line passing through the longest horizontal axis of the external meatus opening, was established. We then measured the distance between the RP and the soft tissue depression in a portrait and the bone depression on a computed tomography (CT) scan. The discrepancy between these distances was quantified.Results: Among the patients with isolated zygomatic arch fractures, only those with a fully visible ear on a side-view photograph were included. Twenty-four patients met the inclusion criteria. There were four types of discrepancies in the location of the soft tissue depression compared to the bone depression: type I, forward and upward discrepancy (7.45 and 3.28 mm), type II, backward and upward (4.29 and 4.21 mm), type III, forward and downward (10.06 and 5.15 mm), and type IV, backward and downward (2.61 and 3.27 mm).Conclusion: This study showed that discrepancy between the locations of the depressions on the soft tissue and bone exists in various directions. Therefore, applying the transverse and vertical distances measured from a bone image of the CT scan onto the patient’s face at the indicated RP will be helpful for predicting the reduction location. Abbreviations: 3D, 3-dimensional; CT, computed tomography; RP, reference point

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Florez, Edward, Toms Vengaloor Thomas, Candace M. Howard, Hamid Khosravi, Seth T. Lirette, and Ali Fatemi. "MACHINE LEARNING BASED ON CT RADIOMIC FEATURES PREDICTS RESIDUAL TUMOR IN HEAD AND NECK CANCER PATIENTS TREATED WITH CHEMORADIOTHERAPY." Biomedical Sciences Instrumentation 57, no. 2 (April 1, 2021): 199–211. http://dx.doi.org/10.34107/yhpn9422.04199.

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Surveillance imaging of HNSCC in patients treated with chemoradiotherapy suffers from difficulty in differentiating residual disease from radiation changes and inflammation. Thus, this study assessed ML models based on RadFs extracted from standard CT images pre- and post-chemoradiation to predict HNSCC treatment response. A retrospective analysis of HNSCC patients treated with definitive chemoradiotherapy at our institution between 2006 and 2015 was performed. Thirty-six patients with residual disease on CT scans of the soft tissue of the neck at a two- month interval-either in the primary site, nodal stations, or both-were enrolled. GTV contours from the treatment planning CT (CT1), post-treatment CT (CT2), and CT portion of the PET/CT (CT3) of the neck were exported to MatLab®, where 2D and 3D RadFs were extracted using different methods. Finally, ML models were used to identify the RadFs that predict changes and progression in HNSCC patients treated with chemoradiotherapy. SVM models using 2D RadFs, extracted from CT2, were associated with residual disease on PET/CT exams (AUC = 0.702). 2D RadFs extracted from PET/CT had moderate predictive ability to predict positive pathology for residual tumor (AUC = 0.667). NN and RF models of 3D RadFs extracted from CT2 and PET/CT had good and moderate predictive ability to predict positive pathology for residual tumor (AUC = 0.720 and 0.678, respectively). ML models using 2D and 3D RadFs derived from pre- and post-treatment CT data show promise for predicting residual tumor from radiation changes and inflammation in a small group of HNSCC cancer patients treated with chemoradiotherapy.

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Hatami, Mohsen, Dongmei Wang, Aili Qu, Zeng Xiangsen, Qiugen Wang, and Behzad Baradaran Kazemian. "Dynamic Simulation of Biomechanical Behaviour of the Pelvis in the Lateral Impact Loads." Journal of Healthcare Engineering 2018 (September 18, 2018): 1–11. http://dx.doi.org/10.1155/2018/3083278.

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The objective of this study was to develop and validate a novel 3D dynamic model of a pelvic side-impactor system. The biomechanical responses of a pelvic flexible model (having .mnf file suffix) under the lateral impact load for predicting the bone fracture mechanism are investigated as well. The 3D solid model of the side-impactor system was imported into MSC/ADAMS software for analyzing the dynamic model, and the pelvic flexible model was extracted from the CT images of a Chinese female volunteer. The flexible model of the pelvis system was developed considering a wide range of mechanical properties in the bone complex and soft tissue to achieve a realistic biomechanical response during a lateral impact. Good agreements were achieved between the dynamic simulations and the experimental results of pelvic side impacts, in terms of the biomechanical criteria. The dynamic model of impactor system could be employed to investigate the hip protector effectiveness, improving the vehicle safety, and biomechanical response of the other human organs.

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Ma, Wen, Shiwei Niu, Lidong Wang, Canbang Peng, Shuai Fu, Changbin Zhang, Qingying Cui, Sihang Wang, Ming Li, and Yanhua Xu. "Clinical Application of Individualized 3D-Printed Templates in the Treatment of Condylar Osteochondroma." Healthcare 10, no. 11 (October 29, 2022): 2163. http://dx.doi.org/10.3390/healthcare10112163.

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Background: Osteochondroma (OC) is one of the most common benign tumors of the long bones, but it rarely occurs in the maxillofacial skeleton. However, mandibular condylar OC often leads to severe facial deformity in affected patients, including facial asymmetry, deviation of the chin, and malocclusion. This study aimed to explore the clinical application of individualized 3D-printed templates to accurately and effectively treat condylar OC. Methods: A total of 8 patients with mandibular condylar OC were treated from July 2015 to August 2021. The enrolled patients (5 women and 3 men) had a median age of 27 years (range: 21–32 years). All patients exhibited symptoms of facial asymmetry and occlusal disorders preoperatively. The digital software used to virtually design the process consisted of three-dimensional reconstruction, 3D-cephalometry analysis, virtual surgery, individualized templates, and postoperative facial soft-tissue prediction. A set of 3D-printed templates (DOS and DOT) were used in all cases to stabilize the occlusion and guide the osteotomy. Then, pre- and post-operative complications, mouth opening, clinical signs, and the accuracy of the CT imaging analysis were all evaluated. All the measurement data were presented as means ± SD; Bonferroni and Tamhane T2 multiple comparison tests were used to examine the differences between the groups. Results: All patients healed uneventfully. None of the patients exhibited facial nerve injury at follow-up. In comparing the condylar segments with T0p and T1, the average deviation of the condylar segments was 0.5796 mm, indicating that the post-operative reconstructed condyles showed a high degree of similarity to the reconstruction results of the virtual surgical plan. Conclusions: Individualized 3D-printed templates simplified surgical procedures and improved surgical accuracy, proving to be an effective method for the treatment of patients with slight asymmetric deformities secondary to condylar OC.

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Lin, Wei-Han, Zhijie Zhu, Vasanth Ravikumar, Vinod Sharma, Elena G. Tolkacheva, Michael C. McAlpine, and Brenda M. Ogle. "A Bionic Testbed for Cardiac Ablation Tools." International Journal of Molecular Sciences 23, no. 22 (November 21, 2022): 14444. http://dx.doi.org/10.3390/ijms232214444.

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Bionic-engineered tissues have been proposed for testing the performance of cardiovascular medical devices and predicting clinical outcomes ex vivo. Progress has been made in the development of compliant electronics that are capable of monitoring treatment parameters and being coupled to engineered tissues; however, the scale of most engineered tissues is too small to accommodate the size of clinical-grade medical devices. Here, we show substantial progress toward bionic tissues for evaluating cardiac ablation tools by generating a centimeter-scale human cardiac disk and coupling it to a hydrogel-based soft-pressure sensor. The cardiac tissue with contiguous electromechanical function was made possible by our recently established method to 3D bioprint human pluripotent stem cells in an extracellular matrix-based bioink that allows for in situ cell expansion prior to cardiac differentiation. The pressure sensor described here utilized electrical impedance tomography to enable the real-time spatiotemporal mapping of pressure distribution. A cryoablation tip catheter was applied to the composite bionic tissues with varied pressure. We found a close correlation between the cell response to ablation and the applied pressure. Under some conditions, cardiomyocytes could survive in the ablated region with more rounded morphology compared to the unablated controls, and connectivity was disrupted. This is the first known functional characterization of living human cardiomyocytes following an ablation procedure that suggests several mechanisms by which arrhythmia might redevelop following an ablation. Thus, bionic-engineered testbeds of this type can be indicators of tissue health and function and provide unique insight into human cell responses to ablative interventions.

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Aboul-Hosn Centenero, Samir, and Federico Hernández-Alfaro. "3D planning in orthognathic surgery: CAD/CAM surgical splints and prediction of the soft and hard tissues results – Our experience in 16 cases." Journal of Cranio-Maxillofacial Surgery 40, no. 2 (February 2012): 162–68. http://dx.doi.org/10.1016/j.jcms.2011.03.014.

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Ferreira, Teresa, Lorna Grech Fonk, Myriam Jaarsma-Coes, Guido van Haren, Marina Marinkovic, and Jan-Willem Beenakker. "MRI of Uveal Melanoma." Cancers 11, no. 3 (March 17, 2019): 377. http://dx.doi.org/10.3390/cancers11030377.

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Uveal Melanoma (UM) is the most common primary malignant ocular tumor. The high soft tissue contrast and spatial resolution, and the possibility of generating 3D volumetric and functional images, make Magnetic Resonance Imaging (MRI) a valuable diagnostic imaging technique in UM. Current clinical MRI protocols, however, are not optimized for UM and therefore lack the quality for accurate assessments. We therefore developed a dedicated protocol at a 3 Tesla MRI, using an eye coil, consisting of multi-slice 2D sequences, different isotropic sequences and diffusion and perfusion-weighted images. This protocol was prospectively evaluated in 9 uveal melanoma patients. The multi-slice 2D sequences had the highest in-plane resolution, being the most suited for lesion characterization and local extension evaluation. The isotropic 3D Turbo-Spin Echo (TSE) sequences were the most suitable for accurate geometric measurements of the tumor and are therefore important for therapy planning. Diffusion and perfusion-weighted images aid in differentiating benign from malignant lesions and provide quantitative measures on tumor hemodynamics and cellularity, which have been reported to be effective in predicting and assessing treatment outcome. Overall, this dedicated MRI protocol provides high-quality imaging of UM, which can be used to improve its diagnosis, treatment planning, and follow-up.

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Brassey, Charlotte A., Thomas G. O’Mahoney, Andrew C. Kitchener, Phillip L. Manning, and William I. Sellers. "Convex-hull mass estimates of the dodo (Raphus cucullatus): application of a CT-based mass estimation technique." PeerJ 4 (January 11, 2016): e1432. http://dx.doi.org/10.7717/peerj.1432.

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The external appearance of the dodo (Raphus cucullatus,Linnaeus, 1758) has been a source of considerable intrigue, as contemporaneous accounts or depictions are rare. The body mass of the dodo has been particularly contentious, with the flightless pigeon alternatively reconstructed as slim or fat depending upon the skeletal metric used as the basis for mass prediction. Resolving this dichotomy and obtaining a reliable estimate for mass is essential before future analyses regarding dodo life history, physiology or biomechanics can be conducted. Previous mass estimates of the dodo have relied upon predictive equations based upon hind limb dimensions of extant pigeons. Yet the hind limb proportions of dodo have been found to differ considerably from those of their modern relatives, particularly with regards to midshaft diameter. Therefore, application of predictive equations to unusually robust fossil skeletal elements may bias mass estimates. We present a whole-body computed tomography (CT) -based mass estimation technique for application to the dodo. We generate 3D volumetric renders of the articulated skeletons of 20 species of extant pigeons, and wrap minimum-fit ‘convex hulls’ around their bony extremities. Convex hull volume is subsequently regressed against mass to generate predictive models based upon whole skeletons. Our best-performing predictive model is characterized by high correlation coefficients and low mean squared error (a= − 2.31,b= 0.90,r2= 0.97, MSE = 0.0046). When applied to articulated composite skeletons of the dodo (National Museums Scotland, NMS.Z.1993.13; Natural History Museum, NHMUK A.9040 and S/1988.50.1), we estimate eviscerated body masses of 8–10.8 kg. When accounting for missing soft tissues, this may equate to live masses of 10.6–14.3 kg. Mass predictions presented here overlap at the lower end of those previously published, and support recent suggestions of a relatively slim dodo. CT-based reconstructions provide a means of objectively estimating mass and body segment properties of extinct species using whole articulated skeletons.

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Asad, Usman, Shummaila Rasheed, Waqas Akbar Lughmani, Tayyaba Kazim, Azfar Khalid, and Jürgen Pannek. "Biomechanical Modeling of Human–Robot Accident Scenarios: A Computational Assessment for Heavy-Payload-Capacity Robots." Applied Sciences 13, no. 3 (February 2, 2023): 1957. http://dx.doi.org/10.3390/app13031957.

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Exponentially growing technologies such as intelligent robots in the context of Industry 4.0 are radically changing traditional manufacturing to intelligent manufacturing with increased productivity and flexibility. Workspaces are being transformed into fully shared spaces for performing tasks during human–robot collaboration (HRC), increasing the possibility of accidents as compared to the fully restricted and partially shared workspaces. The next technological epoch of Industry 5.0 has a heavy focus on human well-being, with humans and robots operating in synergy. However, the reluctance to adopt heavy-payload-capacity robots due to safety concerns is a major hurdle. Therefore, the importance of analyzing the level of injury after impact can never be neglected for the safety of workers and for designing a collaborative environment. In this study, quasi-static and dynamic analyses of accidental scenarios during HRC are performed for medium- and low-payload-capacity robots according to the conditions given in ISO TS 15066 to assess the threshold level of injury and pain, and is subsequently extended for high speeds and heavy payloads for collaborative robots. For this purpose, accidental scenarios are simulated in ANSYS using a 3D finite element model of an adult human index finger and hand, composed of cortical bone and soft tissue. Stresses and strains in the bone and tissue, and contact forces and energy transfer during impact are studied, and contact speed limit values are estimated. It is observed that heavy-payload-capacity robots must be restricted to 80% of the speed limit of low-payload-capacity robots. Biomechanical modeling of accident scenarios offers insights and, therefore, gives confidence in the adoption of heavy-payload robots in factories of the future. The analysis allows for prediction and assessment of different hypothetical accidental scenarios in HRC involving high speeds and heavy-payload-capacity robots.

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GOMEZ GARCIA, CARMELO, DAVID PIÑEROS HEREDIA, JOSÉ SEBASTIÁN VELÁZQUEZ BLÁZQUEZ, FRANCISCO LUIS SAEZ GUTIERREZ, JORGE LUCIANO ALIO, and FRANCISCO CAVAS MARTINEZ. "GEOMETRICAL MODELLING OF CORNEAL STRUCTURE IN NON-PATHOLOGICAL INITIAL CONDITIONS. A COMPARATIVE STUDY." DYNA 98, no. 1 (January 1, 2023): 73–77. http://dx.doi.org/10.6036/10649.

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Modelling and numerical simulation have involved a great advance in clinical practice for the prediction of the structural behaviour of soft tissues in certain healthy or pathological scenarios. One of the main features of these simulations is that they can define the geometric parameters of the structure in its initial boundary conditions. In the case of the cornea, there are discrepancies with respect to the initial conditions that depend on whether if it is considered its physiological geometry measured in vivo, or otherwise its geometry in its stress-free state. The choice of one or the other could lead to errors in the simulation model due to the non-linearity of these tissues. In this study, two methodologies were evaluated, the displacement method and the prestress method, to obtain the geometry of non-pathological cornea in its free-of-stress state. Both methodologies allow obtaining the physiological geometry measured in-vivo of the healthy cornea, however, the method of displacements presents a computational architecture that makes it more efficient in numerical simulation, when compared to the pre-stress method. Keywords: 3D Modelling; Computational Modelling; Ophthalmology; Biological Morphology

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Davydov, Dmitriy V., Natalya S. Serova, and Ol'ga Yu Pavlova. "Risk prediction of posttraummatic enophthalmos development on the basis of orbital volume calculations using multislice computed tomography data." Ophthalmology journal 11, no. 3 (December 2, 2018): 26–33. http://dx.doi.org/10.17816/ov11326-33.

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Purpose. To elaborate a method of orbital volume measurement in patients with midface trauma at pre- and postoperative stages on the basis of multislice computed tomography (MSCT); to investigate the capabilities of orbital volume measurement to acquire additional diagnostic information and to estimate the risk of postoperative enophthalmos development. Materials and methods. A total of 71 patients (100%) with midface trauma were examined at the Sechenov University clinic. At pre- and postoperative stages, all patients (n = 71, 100%) were examined using MSCT (Toshiba Aquilion One 640) with 0.5 mm slice thickness in bone and soft tissue regimen. To measure orbital volume, MSCT data were processed using Vitrea workstation: bone borders of the right and left orbit were marked before and after surgical treatment on every axial slice, and orbital volumes were presented in ml. Results. Preoperative MSCT data management revealed increased orbital volume due to orbital trauma in 64 patients (90%), the difference between healthy and traumatized orbit was between 2 ml and 14 ml. In these patients, reconstructive surgical procedure was performed. In 7 patients (10%) with mild midface trauma, the difference between orbital volumes was less than 2 ml, this was considered as a positive prognostic factor, and these patients were not subjects to surgical treatment. After surgery, in 55 patients (77%) the orbital volume restored, the difference between orbital volumes was less than 2 ml. In 9 cases (13%), the difference in orbital volume was more than 2 ml, considered as adverse prognostic factor which means that there still was a risk of postoperative enophthalmos development. In this patient group, additional diagnostic examination was necessary, and patients required planning of residual enophthalmos surgical correction with MSCT control during the post-op period. Conclusion. Postprocessing of the MSCT data gave the possibility to calculate pre-and postoperative orbital volume changes and present it in mathematical units (ml) in 3D mode. As the result the additional information can be acquired in order to identify the risk of postoperative enophthalmos.

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De Vita, Alessandro, Federica Recine, Giacomo Miserocchi, Federica Pieri, Anna Farnedi, Francesco Fabbri, Valentina Fausti, et al. "The potential role of extracellular matrix in the activity of trabectedin." Journal of Clinical Oncology 38, no. 15_suppl (May 20, 2020): e23542-e23542. http://dx.doi.org/10.1200/jco.2020.38.15_suppl.e23542.

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e23542 Background: Soft tissue sarcomas (sts) represent a rare group of solid neoplasm of mesenchymal origin with a 1% incidence of all adult cancers. Liposarcoma and leiomyosarcoma (L-sarcoma) are the most common histotypes. The current first-line treatment for advanced/metastatic L-sarcomas is represented by anthracycline based-regimens. Second-line therapy options include trabectedin, eribulin, ifosfamide, gemcitabine and dacarbazine. In particular, the activity of trabectedin, a tetrahydroisoquinoline molecule, as well as its mechanism of action is not completely elucidated. Methods: The study involved six patient affected L-sarcoma. Patient-derived primary cultures were established after patient surgical treatment. Primary cells were cultured in standard monolayer culture and 3D collagen-based scaffolds. In order to gain inside into the mechanism of action of the drugs, genomic-, chemobiogram, proteomic-, cytometer and in silico analysis were performed. Results: The results confirmed the preservation of tumor gene expression in 3D culture model compared to standard monolayer culture. In particular 3D culture system was able to resemble the patient gene expression of TGFb, SLUG, SNAIL, MMP9 compared to 2D. In silico analysis showed an upregulation of COL1A1 gene, the extracellular matrix component of the present 3D model, in sts compared to other tumors. Pharmacological analysis displayed an increased sensitivity to trabectedin in all the 3D L-sarcoma primary culture compared to 2D culture system, while this was not observed with the other drugs. As previous preclinical evidences suggested that trabectedin mechanism of action include the impairing of ECM proteolytic degradation mediated by tumor cells, we think that its high observed sensitivity depend on the presence of collagen in our 3D- model. Conclusions: These results were suggestive of the losing credibility of monolayer standard culture for pharmacology studies and highlight the promising role of 3D patient-derived culture model for the study of sts biology. Moreover these results shed the light on the potential role of ECM in the mechanism of action of trabectedin in L-sarcomas. The work points out the role of this tumor microenvironment component in predicting response to trabectedin and provide the rationale for better stratifying patients which will be candidate for this drug. Further researches are needed to confirm these evidences.

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Marchand, Robert C., Nipun Sodhi, Manoshi Bhowmik-Stoker, Laura Scholl, Caitlin Condrey, Anton Khlopas, Assem A. Sultan, Jared M. Newman, and Michael A. Mont. "Does the Robotic Arm and Preoperative CT Planning Help with 3D Intraoperative Total Knee Arthroplasty Planning?" Journal of Knee Surgery 32, no. 08 (August 15, 2018): 742–49. http://dx.doi.org/10.1055/s-0038-1668122.

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Although several studies highlight the advantages of robotic arm-assisted total knee arthroplasty (RA-TKA), few investigate its intraoperative outcome. Therefore, the purpose of this study was to analyze the RA-TKA's ability to assist with intraoperative correction of: (1) flexion and (2) extension gaps, as well as its ability to (3) accurately predict implant sizes. Additionally, in this RA-TKA cohort, length of stay, complications, and readmissions were assessed. A total of 335 patients who underwent RA-TKA were included. The robotic software virtually measured the intraoperative prebone cut extension and flexion gaps. Differences in medial versus lateral prebone cut extension and flexion gaps were calculated. A total of 155 patients (46%) had an extension gap difference of between –2 and 2 mm (mean, –0.3 mm), while 119 patients (36%) had a flexion gap difference of between –2 and 2 mm (mean, –0.6 mm). Postbone cut differences in medial versus lateral flexion and extension gaps were measured. Balanced knees were considered to have a medial and lateral flexion gap difference within 2 mm. The robot-predicted implant size was also compared with the final implant size. Additionally, lengths of stay, complications, and readmissions were assessed. All patients achieved a postbone cut extension gap difference between –1 and 1 mm (mean, –0.1 mm). A total of 332 patients (99%) achieved a postbone cut flexion gap difference of between –2 and 2 mm (mean, 0 mm). For 98% of prostheses, the robotic software predicted within 1 implant size the actual tibial or femoral implant size used.The mean length of stay was found to be 2 days. No patients suffered from superficial skin infection, pin site infections or fractures, soft tissue damage, and no robotic cases were converted to manual TKA due to intraoperative complications. A total of 8 patients (2.2%) were readmitted; however, none were directly related to robotic use. The robotic software and use of a preoperative computed tomography (CT) substantially helped with intraoperative planning and accurate prediction of implant sizes. Therefore, based on the results of this study, the RA-TKA device does, in fact, provide considerable intraoperative assistance.

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FALCINELLI, CRISTINA, ENRICO SCHILEO, FABIO BARUFFALDI, LUCA CRISTOFOLINI, and FULVIA TADDEI. "THE EFFECT OF COMPUTED TOMOGRAPHY CURRENT REDUCTION ON PROXIMAL FEMUR SUBJECT-SPECIFIC FINITE ELEMENT MODELS." Journal of Mechanics in Medicine and Biology 17, no. 01 (February 2017): 1750012. http://dx.doi.org/10.1142/s0219519417500129.

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Many studies have addressed the modulation of computed tomography (CT) parameters, and particularly of tube current, to obtain a good compromise between the X-ray dose to the patient and the image quality for diagnostic applications. This study aimed at evaluating the influence of dose reduction by means of tube current reduction on the CT-based subject-specific finite element (FE) modeling. To this aim, CT scans at stepwise reduced values of tube current from 180[Formula: see text]mAs to 80[Formula: see text]mAs were performed on: (i) a densitometric phantom, to quantify the changes in the calibration equation; (ii) a fresh-frozen, water submersed, human cadaver femur, to quantify changes in geometry reconstruction and material mapping from CT, as well as strain prediction accuracy, based on the in vitro strain measurements available; (iii) a fresh-frozen human cadaver thigh with soft tissues attached, to quantify FE results changes in conditions similar to those found in vivo. The results showed that the tube current reduction does not affect the 3D modeling and the femur FE analysis. Our pilot study highlights the possibility of performing CT scans with reduced dose to generate biomechanical models, although a confirmation by performing larger studies with clinical CT data is needed.

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Logunova, Oksana Sergeevna, Iuliia Borisovna Kukhta, and Elena Sergeevna Reshetnikova. "Algorithm development for 3D image visualization: algorithm of layerwise transformation in compression and spread of a digital cube." Программные системы и вычислительные методы, no. 4 (April 2020): 69–81. http://dx.doi.org/10.7256/2454-0714.2020.4.34303.

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One of the promising areas of software development is the modeling of shapes of various objects with graphical representation of the process itself. The relevance of creation of such systems is first and foremost substantiated by providing a potential user with opportunity to visualize the process of shaping the object under the influence of external factors. Such software modules are highly demanded in such fields as modeling of deformation of a steel ingot in manufacturing rolled steel, prediction of occurrence of defects caused by external influence upon objects of various shape, as well as visualization of work of technical equipment related to external impact upon the object, which changes its shape as a result of applied forces. Elaboration of such systems allows inventing emulators that are demanded in educational institutions, as they replace expensive equipment for training practical skills of the students. For example, in medical universities, such software and hardware systems can be used for acquiring practical skills of working with medical equipment, like installation of ultrasonography. The standard training process for carrying out ultrasound examination in a medical university consists of two stages: theoretical and practical. In the course of training, students are not allowed to use ultrasonography machine as many times to be able to acquire sufficient skills in working with medical equipment. Therefore, it is relevant to develop an assistant robotic system for training, which would serve as an emulator of an actual ultrasonography equipment. The first stage of implementation of such project is the development of a specialized software product that would allow visualizing the image of human organs in 3D format with an option of scaling, rotation and deformation, which occurs due to application of pressure on soft tissues using special joystick during ultrasonography examination.

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Assis Pellizzon, Antonio Cassio, Wilber Edison Bernaola-Paredes, Nicholas Pascuotte Filippetti, Leonardo Faria Ramos, Monica Lucia Rodrigues, José Guilherme Vartanian, Henrique Perez Carvalho, Rodrigo Nascimento Lopes, and Antonio Cassio Assis Pellizzon. "Refractory advanced osteoradionecrosis (ORN) in the mandible: Analysis of predictive factors, clinical, imaging, and therapeutic characteristics." International Journal of Case Reports and Images 13, no. 1 (May 11, 2022): 1–9. http://dx.doi.org/10.5348/101308z01vb2022cr.

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Introduction: Osteoradionecrosis (ORN) of the jaws is a late, severe and difficult to manage side effect in patients who underwent radiotherapy (RT) in the head and neck region. Treatment remains controversial, especially in refractory cases that do not respond to multiple attempts with different therapies, due to their complex pathophysiology. It is based on conservative non-surgical approaches, even in large resections using free flaps. The present study aims to present and describe a clinical case of refractory ORN treated through microsurgical reconstruction and adjuvant therapies. Case Report: A 51-year-old female patient with oncological background of oral squamous cell carcinoma (OSCC) of the floor of the mouth, previously treated with marginal mandibulectomy, and who subsequently relapsed. In a second surgical time, left hemimandibulectomy was performed, followed by microsurgical reconstruction with the fibular osteomusculocutaneous free flap, besides, dental implants were placed in the perioperative time. Radiotherapy was performed using a 3D conformal technique technique with a total dose of 66 Gy and after six months the patient developed infection in the treated region and it was observed partial exposure of the fibular flap and intra and extraoral purulent drainage, and after imaging analysis the diagnosis of ORN was established. Some non-surgical therapeutic attempts were performed without clinical response and a new surgical approach was performed based on sequestrectomy, the removal of the titanium plaque and dental implants with a second microsurgical reconstruction with forearm fasciocutaneous free flap to cover the soft tissue defect was done. Conclusion: The pathophysiology of ORN remains controversial and the predictive factors for its appearance, development, and progression are still unclear. Marginal mandibulectomy could be associated with a rapid onset of ORN in patients submitted to adjuvant RT and it could be considered as a potential predictive factor. Combined therapies are reliable alternatives for local control in refractory cases and in advanced stages, and surgical removal with microsurgical reconstruction procedures are still a feasible alternative that has shown satisfactory clinical results.

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Hayford, Claude Fiifi, Emma Pratt, John P. Cashman, Owain G. Evans, and Claudia Mazzà. "Effectiveness of Global Optimisation and Direct Kinematics in Predicting Surgical Outcome in Children with Cerebral Palsy." Life 11, no. 12 (November 27, 2021): 1306. http://dx.doi.org/10.3390/life11121306.

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Multibody optimisation approaches have not seen much use in routine clinical applications despite evidence of improvements in modelling through a reduction in soft tissue artifacts compared to the standard gait analysis technique of direct kinematics. To inform clinical use, this study investigated the consistency with which both approaches predicted post-surgical outcomes, using changes in Gait Profile Score (GPS) when compared to a clinical assessment of outcome that did not include the 3D gait data. Retrospective three-dimensional motion capture data were utilised from 34 typically developing children and 26 children with cerebral palsy who underwent femoral derotation osteotomies as part of Single Event Multi-Level Surgeries. Results indicated that while, as expected, the GPS estimated from the two methods were numerically different, they were strongly correlated (Spearman’s ρ = 0.93), and no significant differences were observed between their estimations of change in GPS after surgery. The two scores equivalently classified a worsening or improvement in the gait quality in 93% of the cases. When compared with the clinical classification of responders versus non-responders to the intervention, an equivalent performance was found for the two approaches, with 27/41 and 28/41 cases in agreement with the clinical judgement for multibody optimisation and direct kinematics, respectively. With this equivalent performance to the direct kinematics approach and the benefit of being less sensitive to skin artefact and allowing additional analysis such as estimation of musculotendon lengths and joint contact forces, multibody optimisation has the potential to improve the clinical decision-making process in children with cerebral palsy.

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Bradley, David. "3D printing soft tissue scaffolds." Materials Today 21, no. 4 (May 2018): 322. http://dx.doi.org/10.1016/j.mattod.2018.03.031.

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41

Lewis, Daniel M., Kyung Min Park, Vitor Tang, Yu Xu, Koreana Pak, T. S. Karin Eisinger-Mathason, M. Celeste Simon, and Sharon Gerecht. "Intratumoral oxygen gradients mediate sarcoma cell invasion." Proceedings of the National Academy of Sciences 113, no. 33 (August 2, 2016): 9292–97. http://dx.doi.org/10.1073/pnas.1605317113.

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Hypoxia is a critical factor in the progression and metastasis of many cancers, including soft tissue sarcomas. Frequently, oxygen (O2) gradients develop in tumors as they grow beyond their vascular supply, leading to heterogeneous areas of O2 depletion. Here, we report the impact of hypoxic O2 gradients on sarcoma cell invasion and migration. O2 gradient measurements showed that large sarcoma mouse tumors (>300 mm3) contain a severely hypoxic core [≤0.1% partial pressure of O2 (pO2)] whereas smaller tumors possessed hypoxic gradients throughout the tumor mass (0.1–6% pO2). To analyze tumor invasion, we used O2-controllable hydrogels to recreate the physiopathological O2 levels in vitro. Small tumor grafts encapsulated in the hydrogels revealed increased invasion that was both faster and extended over a longer distance in the hypoxic hydrogels compared with nonhypoxic hydrogels. To model the effect of the O2 gradient accurately, we examined individual sarcoma cells embedded in the O2-controllable hydrogel. We observed that hypoxic gradients guide sarcoma cell motility and matrix remodeling through hypoxia-inducible factor-1α (HIF-1α) activation. We further found that in the hypoxic gradient, individual cells migrate more quickly, across longer distances, and in the direction of increasing O2 tension. Treatment with minoxidil, an inhibitor of hypoxia-induced sarcoma metastasis, abrogated cell migration and matrix remodeling in the hypoxic gradient. Overall, we show that O2 acts as a 3D physicotactic agent during sarcoma tumor invasion and propose the O2-controllable hydrogels as a predictive system to study early stages of the metastatic process and therapeutic targets.

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Pati, Falguni, Dong-Heon Ha, Jinah Jang, Hyun Ho Han, Jong-Won Rhie, and Dong-Woo Cho. "Biomimetic 3D tissue printing for soft tissue regeneration." Biomaterials 62 (September 2015): 164–75. http://dx.doi.org/10.1016/j.biomaterials.2015.05.043.

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Cinar, Hatice Burcu, and Mekin Sezik. "Correlation of Fractional Limb Volume Measurements with Neonatal Morphometric Indices." Gynecologic and Obstetric Investigation 86, no. 1-2 (2021): 94–99. http://dx.doi.org/10.1159/000512749.

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Objectives: Fractional thigh volume (TVol) and fractional arm volume (AVol) measurements by three-dimensional (3D) ultrasound can reveal valuable information on fetal soft tissue development. However, it is not clear whether TVol or AVol provides better estimates of fetal body proportion and adiposity, independent of routine two-dimensional (2D) ultrasound biometry. The primary objective of the current study was to determine the correlations between fractional limb volumes (FLVs) and neonatal anthropometric parameters. Design: In this cross-sectional study, fetal FLVs were obtained within 24 h before term delivery from 40 medically and obstetrically uncomplicated pregnancies scheduled for elective cesarean section. TVol and AVol were determined using offline software. Postnatal morphometric data including birth weight; crown-heel, arm, and leg lengths; head, abdominal, mid-thigh, and mid-arm circumferences; and anterior thigh, biceps, and subscapular skinfold thicknesses were obtained. Pearson and partial correlation analyses were used to determine the relationships across antenatal volume calculations and neonatal indices. Correlation coefficients (r) were calculated. Results: Mean maternal age, BMI, and parity were 29.1 ± 5.4 years, 29.7 ± 3.5 kg/m2, and 1.0 ± 1.3, respectively. AVol showed moderate correlations with most of the neonatal parameters, including mid-thigh circumference (r = 0.683), mid-arm circumference (r = 0.627), birth weight (r = 0.583), head circumference (HC, r = 0.560), and abdominal circumference (r = 0.542). However, TVol was weakly related to only some of the indices. After controlling for gestational age, maternal age, BMI, parity, and 2D ultrasound biometry, TVol was no longer associated with any of the parameters, while AVol was independently correlated with mid-thigh (r = 0.724) and mid-arm circumference (r = 0.560), birth weight (r = 0.502), ponderal index (r = 0.402), HC (r = 0.382), biceps (r = 0.384), and subscapular skinfold thickness (r = 0.350). Limitations: The current design includes limited number of pregnancies with only scheduled cesarean deliveries. Neonatal percent body fat was not calculated, and air-displacement plethysmography was not used to assess neonatal body composition. The study population was Caucasian with a relatively high maternal BMI, which may limit extrapolation of the results to other settings. Conclusions: AVoL measurements by 3D ultrasound before delivery are significantly correlated with most of the neonatal morphometric indices, independent of maternal characteristics and 2D biometric parameters. AVol may have advantages over TVol for assessing limb soft tissue development in term fetuses. Future research can focus on feasibility and predictive ability of AVol measurements in prospective studies that include serial biometry over time.

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Patil, Santosh R., Mohammad Khursheed Alam, Keita Moriyama, Saeka Matsuda, Masahito Shoumura, and Naoto Osuga. "3D CBCT Assessment of Soft Tissue Calcification." Journal of Hard Tissue Biology 26, no. 3 (2017): 297–300. http://dx.doi.org/10.2485/jhtb.26.297.

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45

Schwenzer-Zimmerer, K., L. Kovacs, C. Holberg, P. Hering, R. Sader, and H. F. Zeihofer. "Modern 3D acquiring of soft tissue surfaces." International Journal of Oral and Maxillofacial Surgery 34 (January 2005): 45. http://dx.doi.org/10.1016/s0901-5027(05)81045-8.

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Turnbull, Gareth, Jon Clarke, Frédéric Picard, Weidong Zhang, Philip Riches, Bin Li, and Wenmiao Shu. "3D biofabrication for soft tissue and cartilage engineering." Medical Engineering & Physics 82 (August 2020): 13–39. http://dx.doi.org/10.1016/j.medengphy.2020.06.003.

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47

Kochel, Janka, Philipp Meyer-Marcotty, Friederike Strnad, Michael Kochel, and Angelika Stellzig-Eisenhauer. "3D Soft Tissue Analysis – Part 1: Sagittal Parameters." Journal of Orofacial Orthopedics / Fortschritte der Kieferorthopädie 71, no. 1 (January 2010): 40–52. http://dx.doi.org/10.1007/s00056-010-9926-x.

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Kochel, Janka, Philipp Meyer-Marcotty, Michael Kochel, Susanne Schneck, and Angelika Stellzig-Eisenhauer. "3D Soft Tissue Analysis – Part 2: Vertical Parameters." Journal of Orofacial Orthopedics / Fortschritte der Kieferorthopädie 71, no. 3 (May 2010): 207–20. http://dx.doi.org/10.1007/s00056-010-9943-9.

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Stratton, Scott, Ohan S. Manoukian, Ravi Patel, Adam Wentworth, Swetha Rudraiah, and Sangamesh G. Kumbar. "Polymeric 3D printed structures for soft‐tissue engineering." Journal of Applied Polymer Science 135, no. 24 (September 14, 2017): 45569. http://dx.doi.org/10.1002/app.45569.

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50

Ashurko, I. P., S. V. Tarasenko, A. V. Esayan, and A. I. Galyas. "3D volumetric analysis at implant sites after soft tissue augmentation." Medical alphabet, no. 7 (April 28, 2022): 79–85. http://dx.doi.org/10.33667/2078-5631-2022-7-79-84.

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Background. The role of soft tissues in the survival of dental implants remains one of the most discussed problem of the modern dentistry. Two main parameters such as the width of the keratinized gingiva and thickness of the peri-implant tissues are known to play an important role in the stability of the dental implants. Soft tissues thickness is necessary to achieve an aesthetic long-term stable result. Different methods for increasing soft tissue thickness are described in the literature.Materials and methods. Study included 30 patients with insufficient peri-implant soft tissue thickness. All patients underwent buccal soft tissue thickness augmentation by two different methods: collagen matrix (1 group) and free connective tissue graft (2 group). In the study we evaluated the amount of soft tissue thickness gain by using volumetric 3D- analysis.Results. The amount of soft tissue thickness before surgery was 1,63±0,7 mm in the 1 group, 1,61±0,7 mm in the 2 group. Three months after surgery the amount of soft tissue gain was 1,18±0,11 mm in the 1 group, 1,55 ±0,11 mm in the 2 group.Conclusion. The use of a free connective tissue graft as well as a collagen matrix is an effective method for increasing the thickness of soft tissues in the peri-implant area.

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