ABSTRACT
In mandibular reconstructive surgery, straight surgical plates are predominantly used for osteotomy. In this process, a straight plate is bent to fit to the shape of the patient's defect. This potentially compromises the stability of the plate because of changes in mechanical properties resulting from plastic deformation; however, the effect of plastic deformation on stability has yet been investigated. In this study, we assess the stability of three types of commonly used bent plates for two types of mandible defect cases, using three-dimensional finite element analysis (FEA). We compare the stability of plastically deformed plates with customized plates having the same shape, but not the residual stresses from plastic deformation. The results indicate that while the bearing strength of the bent plate is sufficient, there is much higher stress in the plate due to the residual stresses from the bending process that may significantly decrease the safety of the reconstruction surgery.
Subject(s)
Bone Plates , Mandibular Reconstruction/instrumentation , Finite Element Analysis , Materials TestingABSTRACT
Compared to conventional mandibular reconstruction surgery, a recent approach of virtual planning can reduce surgical time providing reliable surgical outcomes. We present our virtual surgical planning software using automatic segmentation and user-friendly techniques. Evaluation experiments compared with a commercial software prove that the proposed software can achieve successful surgical planning in reduced time with reliable accuracy.
Subject(s)
Imaging, Three-Dimensional/methods , Mandibular Reconstruction/methods , Software , Electronic Data Processing , Fibula/anatomy & histology , Humans , Image Processing, Computer-Assisted/methods , Mandible/anatomy & histology , Programming Languages , Surgery, Computer-Assisted , Tomography, X-Ray Computed , User-Computer InterfaceABSTRACT
This paper introduces a glasses-typed wearable system to detect user's emotions using facial expression and physiological responses. The system is designed to acquire facial expression through a built-in camera and physiological responses such as photoplethysmogram (PPG) and electrodermal activity (EDA) in unobtrusive way. We used video clips for induced emotions to test the system suitability in the experiment. The results showed a few meaningful properties that associate emotions with facial expressions and physiological responses captured by the developed wearable device. We expect that this wearable system with a built-in camera and physiological sensors may be a good solution to monitor user's emotional state in daily life.
Subject(s)
Emotions/physiology , Facial Expression , Monitoring, Physiologic/instrumentation , Female , Humans , MaleABSTRACT
If an early predictor of motor functional outcome after stroke were available, stroke patients would receive more appropriate treatments for motor recovery. We performed a correlation analysis of the electroencephalography (EEG) signal patterns of nine subacute stroke patients (recorded 22.9 ± 7.1 days after onset) and their motor recovery rates (measured 100.2 ± 8.9 days after onset). The beta band spectral power in the bilateral motor cortex after physical upper limb movement correlated significantly with the motor recovery rates [Fugl-Meyer assessment (FMA) scores; Pearson's linear correlation, p <; 0.05]. The R-squared of a regression model of the FMA scores and the EEG features was 0.89. These results suggest that the EEG patterns in motor areas correlate with motor recovery after stroke and can be used as an early predictor of motor functional outcome.