An Automated Dynamic Phantom to Produce a Figure of Merit for the Image Quality of Medical Ultrasound Imaging Systems

No abstract available

Advances in Ultrasonic Cutting to Reduce Unwanted Thermal Effects

No abstract available

Exploration of Thermal Issues in Treatment Planning for Focused Ultrasound Surgery

No abstract available

A Study of Echogenic Regional Anaesthesia Needles in Thiel Cadavers

No abstract available

Automated Transducer Testing and Calibration With a Dynamic Phantom

Variation in transducer array performance for biomedical imaging and non-destructive testing (NDT) is inherent in manufacturing, and performance degradation also occurs when the devices are in service. It is already straightforward to determine basic device functionality through transmit and receive sensitivity measurements and from electrical impedance. However, this requires special equipment and procedures likely to be inaccessible to end users. Nevertheless, validation of transducer performance is of increasing importance as the use of array systems grows for NDT and for medical diagnosis and treatment management by non-specialist users. Our objective here was to produce an automated system for array validation through calculation of the resolution integral (RI). The dynamic phantom that has been developed is based on imaging two filamentary targets positioned in a tank of liquid tissue-mimicking material under computer control. The mechanism for this is reliable and inexpensive, with the filaments coupled magnetically through the tank wall. Images are captured and analysed to assess targets resolution in an automated feedback loop. The new phantom has been tested on a total of 18 imaging systems in clinical use. Results were repeatable and consistent when compared with those produced with more conventional techniques. Furthermore, RI calculation successfully differentiated recent, high quality scanners from others and also differentiated linear flat and convex probes and phased arrays. The dynamic phantom thus offers assessment of ultrasound imaging systems quantitatively for purchasing decisions, delivery acceptance and on-going quality assessment. With further work, it will be developed to test systems rigorously and to benchmark them for comparison and prior to introduction to service

Validation of an Automated Dynamic Phantom to Assess the Performance of Ultrasound System

There are many different approaches to evaluate image quality of ultrasound systems. Usually these tests are carried out manually, they are very time consuming, the results are subjective and repeatability can be poor. As one proposed improvement, the resolution integral produces one single figure of merit for image quality. The work reported here is based on a novel approach for grey-scale testing, based on the resolution integral, which can produce non-subjective and repeatable results for each combination of imaging system and transducer array. A total of 21 systems have been tested with three different depth settings to demonstrate its capabilities