Search results for "imagin."
showing 10 items of 7170 documents
Identifying musical pieces from fMRI data using encoding and decoding models.
2018
AbstractEncoding models can reveal and decode neural representations in the visual and semantic domains. However, a thorough understanding of how distributed information in auditory cortices and temporal evolution of music contribute to model performance is still lacking in the musical domain. We measured fMRI responses during naturalistic music listening and constructed a two-stage approach that first mapped musical features in auditory cortices and then decoded novel musical pieces. We then probed the influence of stimuli duration (number of time points) and spatial extent (number of voxels) on decoding accuracy. Our approach revealed a linear increase in accuracy with duration and a poin…
Accuracy between virtual surgical planning and actual outcomes in orthognathic surgery by iterative closest point algorithm and color maps: A retrosp…
2018
Background To evaluate the accuracy between actual outcomes and virtual surgical planning (VSP) in orthognathic surgery regarding the use of three-dimensional (3D) surface models for registration using iterative closest point (ICP) algorithm and generated color maps. Material and Methods Construction of planning and postoperative 3D models in STL files format (M0 and M1, respectively) from CBCT of 25 subjects who had been submitted to bimaxillary orthognathic surgery was performed. M0 and M1 were sent to Geomagic software in semi-automatic alignment surface mesh order of M0 and M1 for registration using ICP algorithm to calculate mean deviation (MD, MD+, MD-, SD) and root mean square (RMS –…
Evaluation of texture analysis for the differential diagnosis of focal nodular hyperplasia from hepatocellular adenoma on contrast-enhanced CT images
2018
PurposeTo explore the value of CT texture analysis (CTTA) for differentiation of focal nodular hyperplasia (FNH) from hepatocellular adenoma (HCA) on contrast-enhanced CT (CECT).MethodsThis is a retrospective, IRB-approved study conducted in a single institution. A search of the medical records between 2008 and 2017 revealed 48 patients with 70 HCA and 50 patients with 62 FNH. All lesions were histologically proven and with available pre-operative CECT imaging. Hepatic arterial phase (HAP) and portal venous phase (PVP) were used for CTTA. Textural features were extracted using a commercially available research software (TexRAD). The differences between textural parameters of FNH and HCA wer…
Study between anb angle and Wits appraisal in cone beam computed tomography (CBCT)
2013
Objectives: To analyse the ANB and Wits values and to study correlations between those two measurements and other measurements in diagnosing the anteroposterior maxilo-mandibular relationship with CBCT. Study Design: Ninety patients who had previously a CBCT (i-CAT®) as a diagnostic register were selected. A 3D cephalometry was designed using one software package, InVivo5®. This cephalometry included 3 planes of reference, 3 angle measurements and 1 linear measurement. The means and standard deviations of the mean of each measurement were assessed. After that, a Pearson´s correlation coefficient has been performed to analyse the significance of each relationship. Results: When classifying t…
Analyzing the teeth next to the alveolar cleft: Examination and treatment proposal prior to bone grafting based on three-dimensional versus two-dimen…
2016
Abstract Purpose The objective was to evaluate the diagnostic and prognostic value of three-dimensional (3D) cone beam computed tomography (CBCT) on information about the cleft and alignment of cleft neighboring teeth. Materials and methods Panoramic X-rays, small-volume CBCTs, and study casts of 20 patients with a total of 22 alveolar clefts were analyzed prior to secondary bone grafting. Six maxillofacial surgeons and 6 orthodontists rated the following parameters: visibility of alveolar cleft expansion, position and probability of alignment of cleft neighbored teeth. Two-dimensional (2D) X-rays and casts were rated first; CBCT and casts followed at least 4 weeks later. Radiologic bone he…
Presurgical evaluation of bony implant sites using panoramic radiography and cone beam computed tomography—influence of medical education
2017
The aim of this study was to compare the subjective quality rating of panoramic radiography (PAN) and CBCT in the planning of dental implant procedures by clinicians with different educational backgrounds.Radiographic images (PAN and CBCT) of 42 patients were examined as follows: the maxillary (MX) anterior region of patients, the MX posterior region of 16 patients and the mandibular (MD) posterior region of 16 patients. These sites were used for planning of dental implant insertion. Data sets were analyzed by examiners with different training backgrounds: three general practitioners (GP), three oral surgeons (OS) and three maxillofacial surgeons (MS). A standardized questionnaire in a stan…
Linear and Volumetric Mandibular Asymmetries in Adult Patients With Different Skeletal Classes and Vertical Patterns: A Cone-Beam Computed Tomography…
2018
AbstractThis study aimed to quantify the height of the mandibular condyle and ramus, condylar volume, and the asymmetry index in adult patients of different sex, skeletal class and vertical pattern using Cone-Beam Computed Tomography (CBCT), and to determine whether there were differences between these groups. The study used CBCT scans of 159 patients with a mean age of 32.32 ± 8.31 years. InVivoDental® software was used to perform both linear (condylar, ramal, and total height) and condylar volume measurements. Linear and volumetric asymmetries were calculated. There were not significant differences between right and left sides. The mean value obtained for condyle height was 7.27 mm, ramus…
Three-dimensional cone-beam computed tomography for diagnosis of keratocystic odontogenic tumours; evaluation of four cases.
2011
The keratocystic odontogenic tumour (KCOT), formerly known as the odontogenic keratocyst (OKC) is a benign intraosseous lesion that derives from remnants of the dental lamina. Due to its characteristics, clinical and histopathological features and various treatment approaches, this pathology is different comparing with other odontogenic cysts. Radiographically the KCOT appears as well-defined unilocular or multilocular radiolucency with thin radiopaque borders. In most cases, conventional radiographic imaging, such as panoramic views and intraoral periapical films, are adequate to determine the location and estimate the size of an KCOT. However, the clinical use for cone-beam computed tomog…
Implant treatment planning regarding augmentation procedures: panoramic radiographs vs. cone beam computed tomography images.
2015
Objectives To evaluate the impact of cone beam computed tomography (CBCT) imaging on treatment planning regarding augmentation procedures for implant placement. Material and methods Panoramic radiographs and CBCT images of 40 patients requesting single-tooth implants in 59 sites were retrospectively analyzed by six specialists in implantology, and treatment planning was performed. Therapeutic recommendations were compared with the surgical protocol performed initially. Results Bone height estimation from panoramic radiographs yielded to higher measures and greater variability compared to CBCT. The suggested treatment plan for lateral and vertical augmentation procedures based on CBCT or pan…
Confabulation: damage to a specific inferior medial prefrontal system
2008
Confabulation, the pathological production of false memories, occurs following a variety of aetiologies involving the frontal lobes, and is frequently held to be underpinned by combined memory and executive deficits. However, the critical frontal regions and specific cognitive deficits involved are unclear. Studies in amnesic patients have associated confabulation with damage to the orbital and ventromedial prefrontal cortices. However, neuroimaging studies have associated memory-control processes which are assumed to underlie confabulation with the right lateral prefrontal cortex. We used a confabulation battery to investigate the occurrence and localisation of confabulation in an unselect…