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Abstract

This article is devoted to works on using natural user interfaces (NUI) in computer support systems of aircraft service. The concept of such interfaces involves the usage in human-machine communication the same measures as in the communication between people, that is sound or gesture. In the case of gesture communication, it is indispensable to adopt methods related to computer vision algorithms. One of them is a three-dimensional reconstruction of objects based on processing techniques of a pair of two-dimensional images. The above method and the results of its application were presented to obtain a three-dimensional cloud of points describing the hand shape. The obtained software will constitute an element of gesture classifier based on the analysis of the spatial location of the acquired points of the cloud.

-sectional anatomic features of the manus in cadavers of dogs without forelimb disease. Am J Vet Res 2009, 70:1450-1458. 9. Rycke LM, Gielen IM, Bree H, Simoens PJ: Computed tomography of the elbow joint in clinically normal dogs. Am J Vet Res 2002, 63:1400-1407. 10. Vekens EV, Bergman EHJ, Vanderperren K, Raes EV, Puchalski SM, Bree HJ, Saunders JH: Computed tomographic anatomy of the equine stifle joint. Am J Vet Res 2011, 72:512-521. 11. Sora MC, Genser-Strobl B, Radu J, Lozanoff S: Three-dimensional reconstruction of the ankle by means of ultrathin slice plastination. Clin Anat

Summary

The phenomenon “vessels within vessels” was initially described by Merchant S et al. as arteries found free-floating inside the lumen of veins. We have described another version of the “vessels within vessels”complex, composed of arteries found inside the lumen of lymphatic vessels. The purpose of the present study was to describe the structure of the lympho-arterial vascular complex in a breast tissue specimen from a male subject using three- dimensional tissue reconstruction. A histological specimen from a 64 year-old male subject diagnosed with gynecomastia was used. The tissue sample was sectioned in a multi-step manner. An overall of approximately 150pm thick tissue material was sampled. Immunostaining with anti-CD34 antibody and anti-podoplanin antibody was performed. Three-dimensional reconstruction of the vessel within the vessel structure was performed with “Reconstruct” software When the reconstruction of the breast parenchyma was revealed as a 3D image, it became apparent that the arterial vessel was situated inside the lymphatic vessel and could be followed along the entire length of the vascular segment studied. We have proved that these vascular complexes are not artificial phenomenon and do exist. The function of the vascular complexes is still uncertain, and is probably related to lymph propulsions in the initial collector vessels.

Abstract

The aim of this study was to evaluate the mandibular morphometric measurements of male and female rabbits using three-dimensional digital model and real bone measurements. Ten (5 female, 5 male) rabbits with no bone deformities were used in the study. Three-dimensional models were produced from two-dimensional microcomputed tomography images of the rabbit’s mandible. Biometric data were obtained by using the same measuring points over both three-dimensional models and real bone samples. There was only a significant main effect of gender for the greatest length of the mandible, length from aboral border of the alveolus of third molar teeth to infradentale, length of the diastema, height of the vertical ramus (measured in projection), distance from the incisor to the oral border of mental foramen, distance from aboral border of mental foramen to caudal border of mandible, distance between retroalveolar foramen and caudal border of mandible. For these measurements, calculated data for females are significantly higher than the males (p<0.05). It was found to be statistically significant between methods only for the length of the cheek tooth row and height of the vertical ramus values (p<0.05). In this study, it was understood that 3D morphometric measurements for bone tissue could be used with accuracy and reliability especially in anatomy and orthodontics areas as an alternative to traditional measurements made with a digital caliper.

Abstract

The technologies of sonar and laser scanning are an efficient and widely used source of spatial information with regards to underwater and over ground environment respectively. The measurement data are usually available in the form of groups of separate points located irregularly in three-dimensional space, known as point clouds. This data model has known disadvantages, therefore in many applications a different form of representation, i.e. 3D surfaces composed of edges and facets, is preferred with respect to the terrain or seabed surface relief as well as various objects shape. In the paper, the authors propose a new approach to 3D shape reconstruction from both multibeam and LiDAR measurements. It is based on a multiple-step and to some extent adaptive process, in which the chosen set and sequence of particular stages may depend on a current type and characteristic features of the processed data. The processing scheme includes: 1) pre-processing which may include noise reduction, rasterization and pre-classification, 2) detection and separation of objects for dedicated processing (e.g. steep walls, masts), and 3) surface reconstruction in 3D by point cloud triangulation and with the aid of several dedicated procedures. The benefits of using the proposed methods, including algorithms for detecting various features and improving the regularity of the data structure, are presented and discussed. Several different shape reconstruction algorithms were tested in combination with the proposed data processing methods and the strengths and weaknesses of each algorithm were highlighted.

Abstract

Background: Fusion of the spine region for congenital, traumatic, and degenerative lesions is more common now. Many orthopedic surgeons prefer posterior arthrodesis to restore the stability. Several studies have reported benefits, technical demands, clinical results, and postoperative complications with each method. For lumbar spine fusion, the best technique for a particular patient remains controversial.

Objective: We described a technique of posterior spinal fusion that can achieve solid fusion and produce clinical success.

Method: Between June 2008 and May 2010, a single surgeon treated 46 patients with this modified technique of posterior spinal fusion. All patients underwent postoperative computed tomography (CT) with coronal and sagittal three-dimensional reconstruction in assessing lumbar spine fusion. All patients were instructed to complete a self-assessment Oswestry Disability Index (ODI) questionnaire. These patients were analyzed for clinical outcome and fusion rate.

Results: The study group included 24 women and 22 men with a mean age of 71.2. Mean operating time was 106 minutes in a single-level fusion, 133 minutes in a two-level fusion, 210 minutes in a three-level fusion, and 288 minutes in a four-level fusion. The amount of blood loss during the operation and on the first postoperative day was 632 ml in a single-level fusion, 738 ml in a two-level fusion, 986 ml in a three-level fusion, and 1122 ml in a four-level fusion. There were postoperative complications in two patients. The minimum follow-up period was two years. Postoperative ODI was reduced significantly and had evidence of spinal fusion in CT scan assessing.

Conclusions: This posterior spinal fusion technique is effective in degenerative lumbar disease. Success rates have also been noted. This method of fusion can give the osseous fusion. It may also improve the clinical outcome. This modified posterior spinal fusion technique has some benefits when comparing to the previous methods.

Comparison of CT and MRI in diagnosis of cerebrospinal leak induced by multiple fractures of skull base

Background. Multiple basilar skull fracture and cerebrospinal leak are common complications of traumatic brain injury, which required a surgical repair. But due to the complexity of basilar skull fracture after severe trauma, preoperatively an exact radiological location is always difficult. Multi-row spiral CT and MRI are currently widely applied in the clinical diagnosis. The present study was performed to compare the accuracy of cisternography by multi-row spiral CT and MRI in the diagnosis of cerebrospinal leak.

Methods. A total of 23 patients with multiple basilar skull fracture after traumatic brain injury were included. The radiological and surgical data were retrospectively analyzed. 64-row CT (mm/row) scan and three-dimensional reconstruction were performed in 12 patients, while MR plain scan and cisternography were performed in another 11 patients. The location of cerebrospinal leak was diagnosed by 2 experienced physicians majoring neurological radiology. Surgery was performed in all patients. The cerebrospinal leak location was confirmed and repaired during surgery. The result was considered as accurate when cerebrospinal leak was absent after surgery.

Results. According to the surgical exploration, the preoperative diagnosis of the active cerebrospinal leak location was accurate in 9 out of 12 patients with CT scan. The location could not be confirmed by CT because of multiple fractures in 2 patients and the missed diagnosis occurred in 1 patient. The preoperative diagnosis was accurate in 10 out of 11 patients with MRI examination.

Conclusions. MRI cisternography is more advanced than multi-row CT scan in multiple basilar skull fracture. The combination of the two examinations may increase the diagnostic ratio of active cerebrospinal leak.

-tumoural microvessel density in human solid tumours. Br J Cancer , 2002; 86:1566-1577. 8. Digka A, Lyroudia K, Jirasek T, Kasampalidis I, Karayannopoulou G, Kubinova L . Visualisation of human dental pulp vasculature by immunohistochemical and immunofluorescent detection of CD34: A comparative study. Aust Endod J , 2006; 32(3):101-106. 9. Takahashi K, Kishi Y, Kim S . A scanning electron microscope study of the blood vessels of dog pulp using corrosion resin casts. Three-dimensional reconstruction of the pulpal vessels. J Endod , 1982; 8:131-135. 10. Lyroudia K, Nikolaidis N

). Highquality three-dimensional reconstruction and noise reduction of multifocal images from oversized samples. Journal of Electronic Engineering, 24 (5). [8] Montgomery, D.C., Runger, G.C. (2003). Applied Statistics and Probability for Engineers, 3rd ed. John Wiley & Sons. [9] Yio, M.H.N., Mac, M.J., Wong, H.S., Buenfeld, N.R. (2015). 3D imaging of cement-based materials at submicron resolution by combining laser scanning confocal microscopy with serial sectioning. Journal of Microscopy, 258 (2), 151-169.

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