Age dependent changes of the diploe in the human skull

This paper presents an approach to the investigation of age-related morphological changes in the diploe of the human skull. Comparative investigations were performed on 10 dried skulls of young and old individuals. Computer tomography was employed followed by filtering of the digital images to visualise more details of the inner structure of the calvarial bones. As a result of our analysis, we concluded that the diploe of the young individuals was homogenous cancellous bone, which tightly fills the space between the outer and inner tables of the calvarial bones. The diploe of the older individual is more porous, showing a trace of sclerosis and with lacunas. Its texture is more scattered in the images and presents a higher level of degradation. The structural differences of the diploe in the skulls of older individuals can be due to a process of involution related to a diminishing of trabecular density in the cancellous bone. These processes are usually accompanied by fluctuations in the mineral components

Automated measurement of foot deformities : flatfoot, high arch, calcaneal fracture

Radiographic measurements of foot deformities are used to determine, among other things, such conditions as flatfoot, high arch, or calcaneal fracture. Those measurements are achieved by estimating four angles. Manual assessment of those angles is time-consuming not to mention inevitable errors of such approximation. To the best of the authors knowledge, currently there is no research focusing on finding those four angles. In this paper an algorithm for automatic assessment of those angles, based on extremely randomized trees, is being proposed. Moreover this diagnostic assisting system was intended to be as generic as possible and could be applied, to some degree, to other similar problems. To demonstrate usefulness of this method, correlations of automated measurements with manual ones against correlations of manual measurements with manual ones are being compared. The significance level for manual-manual measurements comparison is less than 0.001 in case of all four angles. The significance level for automated-manual measurements comparison is also less than 0.001 in all cases. The results show that the search for the aforementioned angles can be automated. Even with the use of a generic algorithm a high degree of precision can be achieved, allowing for a more efficient diagnosis

Virtual planning of dental implant placement using CT double-scan technique : own experience

Background: The correctness of CT performed with the use of a double-scan technique is the basis for achieving proper quality of 3D reconstructions of the maxilla or mandible and subsequent virtual planning of dental implant placement. The aim of this study was the presentation of the methodology of computed tomography scanning and own experience with the use of the double-scan technique. Material/Methods: The study group included 26 individuals who underwent MDCT with a double-scan technique using a MDCT scanner SOMATOM Sensation (Siemens, Germany). The parameters of the examination: slice-collimation 10x0.75 mm, slice-thickness 0.75 mm. The first CT scan in the procedure was the scan of the patient wearing a radiological prosthesis and occlusal index, which was followed by a separate scan of the radiological prosthesis. These two CT scans were copied and transferred to PC with Procera Software program (Nobel Biocare, Sweden) where dental implant placement was virtually planned. Results: In all 26 patients, precise three-dimensional reconstructions of the anatomical structure were obtained. In 11 patients, on the basis of the virtual planning, the implant placement was performed, 5 patients were referred to preparatory procedures, that is, restoration of the alveolar process, otolaryngological treatment of the maxillary sinuses. The remaining 10 patients did not qualify to the procedure because of unfavorable anatomical conditions. Conclusions: Correct computed tomography with double-scan technique enables virtual planning of dental implant placement, on the basis of which the real procedure of implantation can be performed

Segmentation of bones in magnetic resonance images of the wrist

PURPOSE:   Rheumatoid arthritis (RA) is a disease characterized by progressive and irreversible destruction of bones and joints. According to current recommendations, magnetic resonance imaging (MRI) is used to asses three main signs of RA based on manual evaluation of MR images: synovitis, bone edema and bone erosions. The key feature of a future computer-assisted diagnostic system for evaluation RA lesions is accurate segmentation of 15 wrist bones. In the present paper, we focus on developing a wrist bones segmentation framework. METHOD:    The segmentation procedure consisted of three stages: segmentation of the distal parts of ulna and radius, segmentation of the proximal parts of metacarpal bones and segmentation of carpal bones. At every stage, markers of bones were determined first, using an atlas-based approach. Then, given markers of bones and a marker of background, a watershed from markers algorithm was applied to find the final segmentation. RESULTS:   The MR data for 37 cases were analyzed. The automated segmentation results were compared with gold-standard manual segmentations using a few well-established metrics: area under ROC curve AUC, mean similarity MS and mean absolute distance MAD. The mean (standard deviation) values of AUC, MS and MAD were 0.97 (0.04), 0.93 (0.09) and 1.23 (0.28), respectively. CONCLUSION:   The results of the present study demonstrate that automated segmentation of wrist bones is feasible. The proposed algorithm can be the first stage for the detection of early lesions like bone edema or synovitis

Realizacja i użytkowanie sieci PACS w zakładzie radiologii : doświadczenia własne

Background: DICOM created a common software platform enabling communication between devices from different vendors. This allows the creation of a PACS (Picture Archiving and Communication System) - a hospital network of imaging modalities, graphics workstations, film printers, and archiving devices. The aim of this study was to show the practical aspects of using a heterogeneous PACS, composed of equipment from several vendors. Both advantages and problems in the cooperation of theoretically "DICOM compatible" devices are presented. Material/Methods: A heterogeneous PACS was gradually created in our department between 1998 and 2003, currently consisting o f a Siemens CT multi-row scanner, a GE MRI scanner, a GE rotational angiograph, Siemens, GE, Marconi, and eFilm Medical graphics workstations, and Agfa thermal printers. DICOM 3.0 was used as a common protocol and the 100 Mb Ethernet as the hardware solution. Connectivity and interoperability in such a system were tested. Results: Using the DICOM protocol, it was possible to transfer images from the modality of one vendor to the graphics workstation of another vendor and then use sophisticated software for image processing. It was also possible to use storage devices such as CD recorders for images from modalities without a built-in storage option. In spite o f theoretical DICOM compatibility, in some cases it was not possible to achieve correct communication in practice. Conclusions: DICOM enables the gradual creation of a PACS with devices from different vendors, thus reducing implementation costs. Using a PACS, many different imaging modalities may use the same graphic workstations and digital printers. Usually one could expect full compatibility o f all DICOM devices; however, in practice cooperation is sometimes limited or erroneous, reducing the benefits of the standard. Archiving data on CD-ROMs is a solution which greatly reduces the operational costs of a radiology department

Wartość wirtualnej bronchoskopii tomografii komputerowej w ocenie zmian nowotworowych płuc

Background: The aim of the study was to find an optimal method of bronchial tree examination using CT virtual bronchoscopy and to evaluate the method for its diagnostic accuracy in the assessment of lung malignancies. Additionally, diagnostic accuracy of the used CT system was analyzed. Material/Methods: The examination was conducted in 154 patients from the University Hospital in Cracow and the University Hospital in Leuven (Belgium). The first group of patients was examined using single detector-row HeliCat Flash CT scanner (Philips Medical Systems) in the Department of Radiology of the University Hospital in Cracow. The second group of patients was examined using 16-detectorrow Mx8000 IDT 16 CT scanner (Philips Medical System) in the University Hospital in Leuven, Belgium. Lung lesions were evaluated by their central and segmental localization in bronchial tree and the degree of bronchial tree stenosis was assessed subsequently. Results: It was shown that singleslice CT virtual bronchoscopy allows a reliable evaluation of the lesions with central localization in bronchial tree, while diagnostic accuracy of multislice CT virtual bronchoscopy is comparable with bronchofiberoscopy in the evaluation of lesions with central and segmental localization. Conclusions: As a result of the study it was concluded that type of the used CT system affected the obtained results. Multislice CT is more accurate in assessing the lesions localized in bronchial tree in considerably shorter time