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In vascular interventional radiology, procedures generally start with the Seldinger technique to access the vasculature, using a needle through which a guidewire is inserted, followed by navigation of catheters within the vessels. Visual and tactile skills are learnt in a patient apprenticeship which is expensive and risky for patients. We propose a training alternative through a new virtual simulator supporting the Seldinger technique: ImaGiNe (imaging guided interventional needle) Seldinger. It is composed of two workstations: (1) a simulated pulse is palpated, in an immersive environment, to guide needle puncture and (2) two haptic devices provide a novel interface where a needle can direct a guidewire and catheter within the vessel lumen, using virtual fluoroscopy. Different complexities are provided by 28 real patient datasets. The feel of the simulation is enhanced by replicating, with the haptics, real force and flexibility measurements. A preliminary validation study has demonstrated training effectiveness for skills transfer.

This paper provides a survey of medical applications that make use of Web3D technologies, covering the period from 1995 to 2005. We assess the impact that Web3D has made on medical education and training during this time and highlight current and future trends. The applications identified are categorized into: general education tools; tools for diagnosis; procedures training; and collaborative training. A summary of work that has been carried out to validate these tools is also included in the survey.

We present a simulator for guided needle puncture procedures. Our aim is to provide an effective training tool for students in interventional radiology (IR) using actual patient data and force feedback within an immersive virtual environment (VE). Training of the visual and motor skills required in IR is an apprenticeship which still consists of close supervision using the model: (i) see one, (ii) do one, and (iii) teach one. Training in patients not only has discomfort associated with it, but provides limited access to training scenarios, and makes it difficult to train in a time efficient manner. Currently, the majority of commercial products implementing a medical VE still focus on laparoscopy where eye–hand coordination and sensation are key issues. IR procedures, however, are far more reliant on the sense of touch. Needle guidance using ultrasound or computed tomography (CT) images is also widely used. Both of these are areas that have not been fully addressed by other medical VEs. This paper provides details of how we are developing an effective needle guidance simulator. The project is a multi-disciplinary collaboration involving practising interventional radiologists and computer scientists.

Op3D is a new visualisation system for a surgeon. For the first time, patient-specific medical data sets can be rendered in three dimensions using a powerful compute server, with the reconstructions being delivered across the computer network in real time to the operating theatre. A laptop serves as the client computer and an easy-to-use interface has been developed for the surgeon to interact with and interrogate the patient data. This paper describes the Op3D system and presents the initial results from its use in hepatopancreatic surgery. Examples are given from both preoperative and intraoperative use.

We have investigated the ability to quantitate atherosclerosis in the aortic arch of the Watanabe rabbit using noninvasive 3-D ultrasound. Our methodology utilizes postprocessing of videotaped freehand 2-D interrogations to form a compound 3-D data block. Structures may then be segmented on the attributed grey-scale level and volumes measured. Analysis of 3-D reconstructions revealed a low echo structure in the aortic arch of atherosclerotic rabbits, absent in nonatherosclerotic rabbits, at recognized sites of plaque predilection. This structure volume correlated closely with fatty streak volume determined from histology (r = 0.890). During a 30-week study, this structure volume increased in untreated animals, but was blocked by treatment with the antiatherosclerotic agent probucol. Thus, a new 3-D ultrasound methodology has been used noninvasively to detect and quantitate a low echo structure corresponding to fatty streaks in the Watanabe rabbit aortic arch. This new methodology could potentially aid plaque burden quantification in human peripheral arteries.