Advanced Ultrasonic Imaging Research

Trahey Lab at Duke University, Pratt School of Engineering

Facilities

• Siemens Elegra scanner is available for full-time research and clinical studies. Contains a custom data acquisition card capable of storing 64M samples of radio frequency data in real time. Also includes features common to current state-of-the-art scanners including B-mode, M-mode, CW and spectral Doppler, and Color Flow. Currently equipped with 5, 7.5, and 10 MHz transducers, was well as a Sony UP-5600 MD Digital Color Video Printer and a Sony SVO-9500MD SVHS Videocassette recorder.
• Siemens Antares scanner is located in the Instrumentation Laboratory and available full time for research and clinical purposes. The system has many commercial and custom probes, including the CH6-2, L10-5, Acunav, ISL8, and VF13-5.
• Beowulf style Linux cluster. This cluster consists of (8) compute nodes with dual AMD Opteron 270 processors and 8GB of RAM, (10) compute nodes with dual AMD Opteron 246 processors and 2GB of RAM, (6) compute nodes with dual AMD Opteron 240 processors and 8GB of RAM each, (5) compute node with dual 2.4Ghz Intel Xeon processors and 2GB of RAM, and (1) head node with dual 1.13GHz Pentium III processors, 2GB of RAM, and an 18GB RAID1 SCSI disk array. Each node has a 1000 Mbps connection to a Cisco network switch. For storage, there is (1) file server with dual 2.8GHz Xeon processors, 2GB of RAM, and a 5.5TB SATA RAID5 array on (2) 3ware 9500-12 hardware RAID cards, and (2) file servers with dual 2.2GHz Xeon processors, 2GB of RAM, and 1.92TB IDE RAID5 arrays on (4) 3Ware 7500-8 hardware RAID cards. These file servers also have 1000Mbps connections to the cluster switch.
• Beowulf Linux minicluster, consisting of 8 compute nodes each. Each node contains a 3.0GHz Intel Pentium 4 processor and 1GB RAM. The nodes are coupled with 1000Mbps Ethernet. A total of 40GB disk storage is available within the cluster. The cluster communicates with the Siemens Antares scanner over a 100Mbps Ethernet link.
• 11 Dell Optiplex GX270 2.8GHz Intel Pentium 4 PCs. Each member of our group has a PC on their desk for dedicated data and word processing. Each PC has 2GB RAM and a 40 GB hard drive. All contain rewriteable CD drives. Matlab licenses allow each user to analyze data locally, and all computers are connected by high-speed links. Backups of all user desktops and the storage servers (above) are performed every night to an Overland Library Pro AIT3 tape library.
• 2 3x80, and 1 8x128 8.0MHz custom transducer arrays (Tetrad Inc.)
• Newport 3d automated translation stage with Motionmaster MM3000 controller, 0.1 micron resolution. This stage provides joystick, panel or computer control, and is used for phantom experiments requiring very high translation accuracy in three dimensions.
• Calibrated PVDF membrane hydrophone (Sonic Technologies) for acoustic measurements.
• UHDC flow pump (UHDC, London, Ontario, Canada) and blood-mimicking fluid. This pump supplies a calibrated volume of fluid per unit time. It is able to generate time-varying user-specified and physiological flow waveforms under computer control.
• Phantom fabrication and characterization facility, for the design, development and characterization of phantoms with acoustic and mechanical properties consistent with those of tissue. This includes pistons, custom test fixtures, digitizing oscilloscope connected via GPIB to a PC for data acquisition, function generator, power amplifier, receiver, scales, hot plates, etc.
• Custom acoustic and mechanical tissue mimicking phantom designed with CIRS, Inc. (Norfolk, VA) including multiple 3 mm diameter lesions with calibrated stiffness and acoustic contrast
• RMI (Appleton, WI) lesion contrast phantom with multiple lesions with calibrated positive and negative acoustic contrast

The Instrumentation laboratory features an array of electronic prototyping and testing equipment, including digital oscilloscopes, power supplies, power amplifiers, and function generators. The network of computers in our research group has sophisticated document preparation capabilities as well as software applications for numerical mathematics (e.g. Matlab, LS-DYNA, Hypermesh, PSFLEX), and ultrasound system simulation (e.g. Field II). The Department of Biomedical Engineering has office staff available for administrative and clerical support. The department also maintains a machine shop and a full-time Biomedical Instrument Designer who works exclusively for department research programs.