G. Marcenaro

Integrated imaging for neurosurgery

The authors address using the concept of multimodal bioimage integration at the local area network level, using 3D MRI and PET data of the human head. Here, integration is intended between structural and functional multidimensional images of the same body area of a patient. They analyze the role of present technology and standards (such as the X Window protocol) in providing the physician with a better understanding of the structure-to-function relationships of a given biological organ. They analyze the concept of integration intended as a tool to extract the significative information content from bioimages, i.e. to perform image analysis. The fusion of visual eidetic and linguistic knowledge, which plays an important role in medical diagnosis formation, is seen as a significant step towards obtaining quantitative evaluation of the relevant information content of bioimages.<<ETX>>

A laboratory for computer-assisted orthopaedic surgery

The overall architecture and the objectives of a laboratory devoted to investigate the integration of planning and executing procedures for orthopaedic surgery are presented. The main components of the architecture are a graphic workstation for processing and manipulating medical images in the planning phase, and two industrial robot manipulators, equipped with a number of different sensors, for executing surgical interventions.<<ETX>>

A system for computer and robot assisted knee implantation

This paper describes the first implementation of a system for assisting the surgeon before and during the implant of a knee prosthesis. The semi-automatic procedure we are testing lets the surgeon plan the intervention on a workstation SUN, and aims at the execution of precise resections. Cuts are performed by a robotic manipulator, after a matching phase based on some markers inserted in the femur and the tibia before the pre-operative CT analysis.

Analysis of multidimensional images on the Connection Machine system

The Connection Machine (CM) has been demonstrated to be an efficient and fast computational engine for the solution of many problems related to image processing. The high-level parallelism of the CM naturally fits to many large-scale data intensive applications. In this paper the implementation of parallel algorithms for the analysis of multidimensional images on the CM is presented. Different aspects in the analysis of multidimensional images are considered. In the field of artificial vision, the implementation of algorithms for the filtering of image sequences (both in space and time) and the estimation of the optical flow is described and some results in terms of accuracy and computation time are presented. The processing of three-dimensional images is investigated in the field of biomedical engineering. In this case the goal is the development of algorithms for the 3-D reconstruction of human body segments and their visualization. The parallel implementations exploit the fine grain parallelism allowed by the CM, processing each point of the data on a different processor. This mechanism is allowed by the possibility of dynamically reconfiguring the connectivity of the CM nodes and of defining a huge number of virtual processors. Moreover, as the CM processors operate on one-bit data, it is possible to tune the number of bits for each data point to match the accuracy required by the application.

Use of 24-bit false-color imagery to enhance visualization of multiparameter MR images

Biomedical image analysis workstations can be linked to 3D data-oriented devices for a new approach to image manipulation in biology and medicine. Stereo monitors allow an intuitive approach to medical diagnosis. The use of 3D head-tracking devices allows a more compelling 3D illusion to be generated. A stylus can be used as an electronic knife for dissecting a 3D data set; furthermore, other 3D sensors are available for tracking operator arm movements. The overall character of this work is firmly application oriented, in order to provide concrete operational tools to the medical user. Such tools range from diagnostic up to therapeutic and robotized use of bioimages.

Three-dimensional reconstruction of Paramecium primaurelia oral apparatus through confocal laser scanning optical microscopy

The oral apparatus of the ciliate protozoan Paramecium primaurelia, a single-celled eukaryotic organism, is a highly organized structure whose arrangement is of important taxonomic, phylogenetic and developmental significance. This paper analyses oral structures by means of a confocal laser scanning optical microscope (CLSM), which allows their three-dimensional visualization and measurement. The extraction of the intrinsic three-dimensional information related to the biological objects under investigation can in turn be related to their functional state, according to the classical paradigms of structure to function relationship identification. In our experiments, we acquired different data sets. These are optical slices of the biological sample under investigation, acquired in a confocal situation, through epi-illumination, in reflection. For comparison with conventional microscopy, two-dimensional images were acquired via a standard TV camera coupled to the microscope itself. The volumes obtained by piling up the slices were rendered through different techniques, some of them directly implemented on the workstation controlling the CLSM system, some of them on a SUN SPARCstation 1, where the original data were transferred via an Ethernet link. In this last instance, original software has been developed for the visualization and animation of the three-dimensional structures, under UNIX and X-Window, according to a ray-tracing algorithm.

BIOCELL: An Integrated and Interactive Tool for the Management of Linguistic and Eidetic Biological Data

An exhaustive description of most biological data requires, beside a set of analytic information, an eidetic representation of the data itself. Biocell is a sort of biological atlas containing the linguistic and eidetic description of cell lines, plus a set of tools to correlate, insert, update, manipulate, display and delete such data.

3D Brain Anatomy And Surgery In X-11 Environment

Biomedical images play an important role in clinical practice not only at diagnostic but at therapeutic level as well. In this last context, 3D and 4D anatomical and physiological data sets from multimodality imaging techniques need to be integrated and processed. In this work, a standard networking interface protocol such as the X window system has been used as a suitable environment for simultaneous image display. Furthermore, a model for visual and symbolic integration at voxel level is presented. The X window system, even if suffering of several limitations for graphic applications in the multi-D case, offers interesting features in relationship to this perspective, considering the situation of local area network connected workstations. It allows standardization of the user interface and software portability between various hardware nodes, resulting in a friendly and flexible tool for the final medical user.

Cuore: a graphical user interface to analyze heart wall motion in MR bioimages

A graphical user interface realized using K-Windows for cardiological diagnostic examinations is presented. It is based on optical flow (OF) theory and it represents an useful tool to detect movement of the cardiac wall during the normal pulse rate in cyclic sequences of MR images. The visualization of the movements is realized using a vectorial representation of the original images.

Spatio-temporal analysis of single-celled organisms (protozoa) structures via confocal microscopy

This work aims to study in vivo vesicle formation, transport and fusion during the digestive process of the ciliated protozoan Paramecium primaurelia.