A cost effective simulator for education of ultrasound image interpretation and probe manipulation

Ultrasonography is the lowest cost no risk medical imaging technique. However, reading an ultrasonographic (US) image as well as performing a good US probe positioning remain difficult tasks. Education in this domain is today performed on patients, thus limiting it to the most common cases. In this paper, we present a cost effective simulator that allows US image practice and realistic probe manipulation from CT data. More precisely, we tackle the issue of providing a realistic interface for the probe manipulation with a basic haptic feedback.

Clinical evaluation of a respiratory gated guidance system for liver punctures

We have previously proposed a computer guidance system for liver punctures designed for intubated (free breathing) patients. The lack of accuracy reported (1 cm) was mostly due to the breathing motion that was not taken into account. In this paper we modify our system to synchronise the guidance information on the expiratory phases of the patient and present an evaluation on 6 patients of our respiratory gated system. Firstly, we show how a specific choice of patient allows us to rigorously and passively evaluate the system accuracy. Secondly, we demonstrate that our system can provide a guidance information with an error below 5 mm during expiratory phases.

A Complete Augmented Reality Guidance System for Liver Punctures: First Clinical Evaluation

We provided in an augmented reality guidance system for liver punctures, which has been validated on a static abdominal phantom. In this paper, we report the first in vivo experiments. We developed a strictly passive protocol to directly evaluate our system on patients. We show that the system algorithms work efficiently and we highlight the clinical constraints that we had to overcome (small operative field, weight and sterility of the tracked marker attached to the needle...). Finally, we investigate to what extent breathing motion can be neglected for free breathing patient. Results show that the guiding accuracy, close to 1 cm, is sufficient for large targets only (above 3 cm of diameter) when the breathing motion is neglected. In the near future, we aim at validating our system on smaller targets using a respiratory gating technique.