MULTICENTRE COMPARISON OF PATIENT AND DETECTOR DOSE FOR X-RAY-GUIDED EMBOLISATIONS OF ARTERIOVENOUS MALFORMATIONS IN THE BRAIN.

Dosimetric benchmarking at four hospitals was performed to investigate incident entrance dose and dose rate on a phantom, and entrance detector dose and dose rate for protocols that are used in routine clinical practice for complex neuroradiological treatment of arteriovenous malformations (AVMs). Measurements were performed with a head phantom that simulates the attenuation and scattering of the human head for the lateral and posteroanterior (PA) views. For fluoroscopy, the measured incident entrance dose rate and entrance detector dose rate were in the range of 44-172 and 0.

MULTICENTRE COMPARISON OF IMAGE QUALITY FOR LOW-CONTRAST OBJECTS AND MICROCATHETER TIPS IN X-RAY-GUIDED TREATMENT OF ARTERIOVENOUS MALFORMATION IN THE BRAIN.

The treatment of brain arteriovenous malformations (AVMs) can be performed as a minimally invasive X-ray-guided procedure using a microcatheter for navigation to reach the target site. The performance of the interventional vascular surgery devices used for AVM was compared in four hospitals. The relation between image quality and the entrance surface air kerma (ESAK) was assessed for the default protocols for digital subtraction angiography (DSA) and fluoroscopy.

A RFID specific participatory design approach to support design and implementation of real-time location systems in the operating room.

Information technology, such as real-time location (RTL) systems using Radio Frequency IDentification (RFID) may contribute to overcome patient safety issues and high costs in healthcare. The aim of this work is to study if a RFID specific Participatory Design (PD) approach supports the design and the implementation of RTL systems in the Operating Room (OR). A RFID specific PD approach was used to design and implement two RFID based modules.

Safety status system for operating room devices.

Background: Since the increase of the number of technological aids in the operating room (OR), equipment-related incidents have come to be a common kind of adverse events. This underlines the importance of adequate equipment management to improve the safety in the OR.

Objective: A system was developed to monitor the safety status (periodic maintenance and registered malfunctions) of OR devices and to facilitate the notification of malfunctions.

Unbinding of targeted ultrasound contrast agent microbubbles by secondary acoustic forces.

Targeted molecular imaging with ultrasound contrast agent microbubbles is achieved by incorporating targeting ligands on the bubble coating and allows for specific imaging of tissues affected by diseases. Improved understanding of the interplay between the acoustic forces acting on the bubbles during insonation with ultrasound and other forces (e.g.

Dynamics of coated microbubbles adherent to a wall.

Molecular imaging with ultrasound is a promising noninvasive technique for disease-specific imaging, enabling for instance, the diagnosis of thrombus and inflammation. Selective imaging is performed by using ultrasound contrast agent microbubbles functionalized with ligands, which bind specifically to the target molecules. Here, we investigate in a model system, the influence of adherence at a wall on the dynamics of the microbubbles, in particular, on the frequency of maximum response, by recording the radial response of individual microbubbles as a function of the applied acoustic pressure and frequency.

"Compression-only" behavior: a second-order nonlinear response of ultrasound contrast agent microbubbles.

Oscillating phospholipid-coated ultrasound contrast agent microbubbles display a so-called "compression-only" behavior, where it is observed that the bubbles compress efficiently while their expansion is suppressed. Here, a theoretical understanding of the source of this nonlinear behavior is provided through a weakly nonlinear analysis of the shell buckling model proposed by Marmottant et al. [J.

Subharmonic behavior of phospholipid-coated ultrasound contrast agent microbubbles.

Coated microbubbles, unlike tissue are able to scatter sound subharmonically. Therefore, the subharmonic behavior of coated microbubbles can be used to enhance the contrast in ultrasound contrast imaging. Theoretically, a threshold amplitude of the driving pressure can be calculated above which subharmonic oscillations of microbubbles are initiated.

Nonlinear shell behavior of phospholipid-coated microbubbles.

The influence of the stabilizing phospholipid-coating on the nonlinear dynamics of ultrasound contrast agent microbubbles is investigated. We record the radial dynamics of individual microbubbles with an ultra high-speed camera as a function of both driving pressure and frequency. The viscoelastic shell was found to enhance the nonlinear bubble response at acoustic pressures as low as 10 kPa.