Biomedical subjects

J Raczkowsky

Publications and source records attributed to J Raczkowsky.

24 records · Page 2Linked to original sources

PubMed2000

A real-time CORBA based system architecture for robot assisted craniofacial surgery.

We present the concept of a system architecture for the computer aided craniofacial surgery. The architecture is based on CORBA, an industrial standard specification for the development of distributed applications. Our concept includes a fundamental behaviour oriented communication model and some fundamental software safety considerations. We've developed a standard library for the integration of new services and devices into our system architecture. It decreases development time noticeably. We tested the performance and usability of our concept on an evaluation set up consisting of a surgery robot system, an infrared navigation system, a force-torque sensor and a visualisation software, obtaining excellent results. Future work will consist in the integration of further devices and the extension of our safety concept. An accurate clinical evaluation will take place continuously.

Computer Graphics↗

PubMed2000

Texture mapping based visualisation methods for the manipulation of CT data: interaction and ergonomics.

The manipulation of large CT datasets needs fast visualisation methods for a comfortable user interaction. Modern visualisation techniques make use texture hardware in graphics workstations extensively. In the following we will present an interactive tool for the positioning of anatomical landmarks in CT datasets of non-pathological children. The tool includes a fast visualisation of CT cross sections based on a texture mapping technique and an interactive three-dimensional view of the segmented CT dataset.

Cephalometry↗

PubMed2000

Synthesis of CAD/CAM, robotics and biomaterial implant fabrication: single-step reconstruction in computer-aided frontotemporal bone resection.

The preoperative manufacturing of individual skull implants, developed by an interdisciplinary research group at Ruhr-University Bochum, is based on the use of titanium as the most common material for implants at present. Using the existing technology for materials that can be milled or moulded, customized implants may be manufactured as well. The goal of the study was to examine biodegradable materials and to evaluate the practicability of intraoperative instrument navigation and robotics. Data acquisition of an adult sheep's head was performed with helical computer tomography (CT). The data were transferred onto a computer aided design/computer aided manufacturing system (CAD/CAM system), and two complex defects in the frontotemporal skull were designed. Standard individual titanium implants were milled for both of the defects. Additionally, for one of the defects a resection template, as well as a mould for the biodegradable poly(D,L-lactide) (PDLLA) implant, were fabricated by the CAD/CAM system. A surgeon carried out the first bone resection (#1) for the prefabricated titanium implant using the resection template and an oscillating saw. The robot system Stäubli RX90CR, modified for clinical use, carried out the other resection (#2). Both titanium implants and the PDLLA implant were inserted in their respective defects to compare the precision of their fit. A critical comparison of both implant materials and both resection types shows that fabrication of a PDLLA implant and robot resection are already possible. At present, the titanium implant and resection using a template are more convincing due to the higher precision and practicability.

Absorbable Implants↗

PubMed1998

Planning and simulation of medical robot tasks.

Complex techniques for planning and performing surgery revolutionize medical interventions. In former times preoperative planning of interventions usually took place in the surgeons mind. Today's new computer techniques allow the surgeon to discuss various operation methods for a patient and to visualize them three-dimensionally. The use of computer assisted surgical planning helps to get better results of a treatment and supports the surgeon before and during the surgical intervention. In this paper we are presenting our planning and simulation system for operations in maxillo-facial surgery. All phases of a surgical intervention are supported. Chapter 1 gives a description of the medical motivation for our planning system and its environment. In Chapter 2 the basic components are presented. The planning system is depicted in Chapter 3 and a simulation of a robot assisted surgery can be found in Chapter 4. Chapter 5 concludes the paper and gives a survey about our future work.

Algorithms↗

PubMed1997

[Robotics in oral and maxillofacial surgery. Possibilities, chances, risks].

Robot systems are being tested in stereotactic neurosurgical interventions, orthopedic surgery of the hip or knee and advancal endoscopic systems for minimally invasive surgery. In contrast to most industrially manufactured products, objects for medical treatment are characterized by plasticity as well as by complex and individual forms. Thus, features of robots in this field have to be further developed in terms of advanced sensory and specific micromotoric systems. Safety and cooperation between surgeon and robot on the patient in the operating room have to be guaranteed. Extensive three-dimensional diagnosis, computer-aided planning and simulation of the intervention as well as sensory systems that monitor the actual performance of the operation are mandatory parts of this concept. In our interdisciplinary study, we aim to examine whether a robot-given a complete preoperative planning and simulation procedure-is able to perform certain surgical operations more precisely than the surgeon. Examples are drilling with depth control, shaping of bone surface by milling, sawing with defined depth in cranial osteotomies, defined preparation of implant sites and the positioning and insertion of dental and other surgical implants, whereby autonomous employment of the robot is not that which is aspired to in these interventions but rather the interactive support of the surgeon.

Humans↗

PubMed1996

A communication system supporting simultaneous planning and execution in cranio-maxillo-facial surgery.

This paper describes the development of a system for simultaneous planning and execution of surgical operations in the cranio-maxillo-facial area. Simultaneous planning and execution is the process of taking an implicit task description, planning a sequence of explicit execution commands (e.g. for robots) and monitoring their execution. As the execution planning process is run completely on-line, during the execution of the assembly task, the planning process is highly reactive, based on sensor information about the robot's present environment. In order to meet the problem that medical data are usually complex and need time-consuming preprocessing, an appropriate architecture for evaluating sensor data has been developed. In this paper, a detailed presentation of the phases of execution planning and sensor data evaluation is given. As an example, the execution of a LeFort I osteotomy is presented.

Computer Communication Networks↗