This month’s column highlights some of the ultrasound news from the 83rd Scientific Assembly and Annual Meeting of the Radiological Society of North America (RSNA), held December 1997 in Chicago.
This column highlights some of the ultrasound news from the 83rd
Scientific Assembly and Annual Meeting of the Radiological Society
of North America (RSNA), held December 1997 in Chicago.
By: Linda E. Ketchum
Ultrasound pursues harmonics, microbubbles, panoramic imaging,
and the 3rd dimension
Acuson demonstrates NativeTM Tissue Harmonic Imaging
Some patients who are difficult to image with ultrasound require
additional tests or repeated ultrasound exams. Difficult-to-image
patients may include those who are overweight, elderly, or
muscular; those with narrow rib spaces, thick body walls, excessive
scarring, or multiple gestations; and patients who have undergone
surgery, chemotherapy, or radiation therapy.
To help solve this problem, Acuson Corporation (Mountain View,
CA) has developed Native Tissue Harmonic Imaging. This technology
transmitslower-frequency sound waves to improve penetration, while
receiving and processing only higher frequency echoes produced by
the body's inherent harmonic characteristics, explained Acuson.
This application is now available for the SequoiaTM system (figure
1), and should be available by mid-1998 for the AspenTM system.
"Native Tissue Harmonic Imaging may be as significant a
development in the history of ultrasound as color Doppler," said
Philip W. Ralls, MD, professor of radiology, Los Angeles
County/University of Southern California Medical Center. He said
that the technology provides images superior to conventional
ultrasound in about 80 to 90% of patients, "especially
difficult-to-image patients." Acuson estimates that these patients
may comprise 20 to 30% of those referred for ultrasound
"Microsonography" performed with high-resolution
Acuson also displayed its 15L8w, part of the MICROSONTM
high-resolution transducer family, as a work-in-progress.
"Combining high-resolution,high-frequency technology with a wide
footprint, the 15L8w gives us the ability to display extremely
small abnormal lesions with the surrounding normal tissueon a
single frame," said Peter Murphy, RDMS, chief sonographer at North
Coast Radiology in Lismore, Australia. With the new transducer, "we
candisplay dynamically the relation of tendons and muscles
interacting with the surrounding tissue. As a result, we can better
understand the nature of muscle/tendon injury and we also can
follow the healing process duringtreatment," he explained.
According to Acuson, this family of transducers will create a
"new era of microsonography," and can be useful for small-parts
applications such as imaging the breast, testes, salivary glands,
pediatric kidneys, andperipheral nerves. With enhanced gray-scale
imaging and color Doppler, this new transducer allows for
visualization of microvasculature, said Acuson.
Color SieScapeTM panoramic imaging
SieScape, the panoramic imaging technology from Siemens Medical
Systems, Inc. (Issaquah, WA), will soon be available in color.
SieScape collects thousands of single images and combines then
instantly into a dynamic image of the entire area being scanned.
Color SieScape may simplify routine color-flow ultrasound scans,
according to Siemens, and enable clinicians to collect a more
complete data set to assess blood flow in carotid arteries, check
for aortic aneurysms, verify vessel patency, and evaluate the
success of vessel grafts in bypass operations. In addition, the
company said that Color SieScape may improve assessments of
perfusion by depicting patterns of blood flow to organsand tumors
in a single, panoramic ultrasound image.
Siemens is developing other advanced applications with its
CrescendoTM MultiDimensional Image Processor, a supercomputer
described by the company as capable of processing 4 billion
instructions per section. Future applications in development are
real-time three-dimensional (3D) imaging, quantitativecontrast
imaging, and automatic calculation programs.
Hitachi EUB-8000 now fully digital
Hitachi Medical Systems (Tarrytown, NY) introduced its new fully
digital EUB-8000 ultrasound system. With Quadra MAX Imaging, the
system offers advancedimaging capabilities with linear, convex,
phased-array, and phased-convex-array transducer technology.
According to Hitachi, the system's QUAD ImageProcessing, using the
MAX Quadra Beamformer, receives acoustic data from the patient at a
rate four times higher than most conventional ultrasound
The system also features DIGITAL Dual Vector Doppler
architecture, which allows the physician or sonographer to select
two separate vectors forcomparison of flow data. The operator also
can independently control each vector for beam direction, sample
width and depth, gain control, wall filter,baseline shift, and
Doppler angle correction, explained Hitachi.
"We're developing some new transducer crystal designs that will
enable the EUB-8000 to improve its capabilities by focusing on
higher sensitivity and broader band-widths," said Rich Murphy,
senior manager for product planning and marketing at Hitachi. These
transducers are based on multiple layers of proprietary
piezo-ceramic design. Since Hitachi is a giantelectronics company,
noted Mr. Murphy, the ultrasound developers here can take advantage
of high technology that's not always available to other ultrasound
Kodak's dedicated ultrasound PACS
Eastman Kodak Company (Rochester, NY) displayed new
image-handling features and connectivity enhancements to the Access
digital image management network, a dedicated ultrasound system.
Access supports the acquisition and storage of gray-scale and color
images, as well as dynamic loops. For example, the system now
allows sonographers to create notes online and attach them to
patient studies, and a "study compare" function enables users to
independently control several patient studies for side-by-side
Features designed to improve workflow include the SmartClerk
background operation, which is initialized at the start of each
exam. "SmartClerk checks the local database for previous studies
from the same patient, creates a new electronic 'study folder,' and
queues the folder for immediate use on the network. The SmartLoad
operation then begins routing theseelectronic patient 'folders' and
images to the Access workstations according to the user-defined
workflow," explained Roger Camp, director of general imaging for
ultrasound products at Kodak's Health ImagingDivision.
On February 3, 1998, a DICOM "query/retrieve" function became
available. This new feature enables clinicians to view images from
other modalities, such as x-ray computed tomography (CT), and
magnetic resonance (MR), from the Access workstation. Access, which
is DICOM-compliant, can be integrated into an overall picture
archiving and communication system (PACS). (DICOM stands for
Digital Imaging and COmmunications in Medicine, the standardfor
electronic image data transfer.)
Harmonics and Flash Echo from Toshiba
Toshiba America Medical Systems (Tustin, CA) introduced the
PowerVision 7000system, based on an all-digital platform. The
company also announced two works-in-progress technologies: a
harmonics package, to use with ultrasoundcontrast agents, and Flash
Echo imaging. Designed for the all-digital PowerVision 7000 system,
the harmonics package enables the system to detectmicrobubble
vibrations of a contrast medium. With harmonics, the system
separates the contrast echo from the tissue echo; higher
frequencies, known as"harmonic frequencies," are generated by
microbubbles. With Flash Echo, ultrasound transmission is used
intermittently to preserve contrast agent microbubbles, which
collapse when ultrasound is pulsed continuously. Clinicians can
customize transmission intervals to the characteristics of the
contrast agent. With Flash Monitoring Mode, the system can display
side-by-side Flash Echo and real-time images.
According to Toshiba, when the PowerVision 7000's
high-frame-rate imaging is combined with Flash Echo, the system can
accumulate and store up to15 frames of consecutive information.
This feature ensures that highly enhanced microbubble images are
obtained during the first transmission, and thatsuccessive frames
capture accumulations of new microbubbles as the region begins to
perfuse, explained Toshiba, which should improve detection of
dynamicchanges in contrast clarity.
GE to acquire Diasonics
On February 13, 1998, GE Medical Systems (Milwaukee, WI)
announced an agreement to acquire Diasonics Vingmed Ultrasound,
Ltd. (Santa Clara, CA), adivision of Elbit Medical Imaging (Haifa,
Israel), for $230 million. "This acquisition represents our entry
into cardiology ultrasound, the fastest-growing segment in the
industry," said Jeffrey R. Immelt, president and chief executive
officer (CEO) of GE Medical Systems. He said that the company had
not yet decided if GE will retain the Diasonics brand name, or
whether to move U.S. base of Diasonics from California to
At RSNA 1997, GE announced that it had received clearance from
the U.S. Food and Drug Administration (FDA) for 3DViewTM for use on
its LOGIQ 700 MRultrasound system. "Our vision is that someday all
ultrasound will be done in 3D," said Omar Ishrak, global ultrasound
general manager at GE. "For 3D imaging to be diagnostically
relevant, it must have uncompromisedimage quality, fast
reconstruction times, and it must be integrated into the system,
making it easy to use. We invested in 1024-acquisition-channel
active matrix arrays because we feel this level of technology is
required to achieve the reduced beam-slice thickness necessary for
exceptional 3DView imaging," said Mr. Ishrak.
A radiologist at Emory Healthcare (Atlanta, GA) reports that
speech recognition technology is having more of an impact on
workflow than a filmlesspicture archiving and communication system
(PACS). "I have found that speech recognition is far more important
to report turnaround and the overallefficiency of the department
than PACS," said Richard Stiles, MD, a radiologist at Emory Clinic
North. (Emory Healthcare includes The Emory Clinic, Inc. and The
Reduce transcription costs by 80%
Dr. Stiles has been involved in test-piloting a filmless PACS,
as well as the PowerScribe radiology speech recognition system from
The MRC Group(Cleveland, OH). In June, 1997, the company installed
five pilot test stations for speech recognition. Emory now plans to
expand the number of PowerScribestations to 30 or 35, and predicts
that speech recognition can reduce its $500,000 annual expenditure
on transcription by 80%.
The old dictation system in place now at Emory requires
radiologists to dictate their reports into a "tank." Reports are
then pulled from thetank for transcription, a system that costs
$500,000 per year at Emory. The time elapsed from exam completion
to the signed report can range from two to 40hours.
"Physicians can't wait up to 40 hours to take some kind of
clinical action," said Scott Wheeler, manager of radiology
information systems at Emory Healthcare. "Often, they have to make
a medical diagnosis before the radiology report is complete. We are
concerned that important factors of a diagnosis may be missed," he
Keeping radiology in the loop
If referring physicians are making diagnoses without radiology
reports, radiology may eventually be taken out of the loop on many
clinical cases. Inaddition, insurance companies view excessive
turnaround times for medical reports as a quality control problem,
which can increase patient lengths ofstay in hospitals and
contribute to rising healthcare costs.
Speech recognition with PowerScribe can save physician dictation
time through the use of "canned normals" and macros. This feature
enablesradiologists to reduce their dictation time by speaking
short phrases, such as "normal chest," which translates into
standard sentences, paragraphs, or entire reports. Radiologists can
customize their own normals or usedepartmental macros shared among
several radiologists. "We anticipate that 60 to 70% of the workload
will be driven by macros," said Mr. Wheeler.
Over the past several years, voice recognition technology has
greatly improved. With continuous speech recognition, radiologists
can dictate reportswithout altering their natural speech
Works with standard PCs, interfaces with RIS
Emory chose MRC's PowerScribe for several reasons: The system is
designed to fit with the natural workflow of the radiologist. It
features a handheld microphone with standard dictation controls
(play, rewind, record, etc.) to which radiologists are accustomed.
PowerScribe is based on a proprietary speech recognition algorithm,
combined with a proprietary language model of 26,000 words, which
results in high rates of recognition and accuracy.Each radiologist
can determine his or her own dictation review process.
PowerScribe works with standard personal computers, so the
hardware investment is lower than with other speech recognition
systems available toradiology. In addition, PowerScribe can
interface with an existing radiology information system (RIS).
"Chest x-rays and ultrasounds are my biggest volume here. Since
I began using the continuous speech recognition system, I have
easily achieved 95%recognition, and often 100%. Compared with other
systems I have evaluated, I like PowerScribe because it allows me
to dictate several reports in a row andthen go into a signing
mode," said Dr. Stiles.
American Institute of Ultrasound in Medicine Ultrasound
The AIUM's Ultrasound Practice Accreditation Commission offers
ultrasound practices in the U.S., Canada, and Puerto Rico an
opportunity to examine their standards and practices and compare
them with nationally accepted ones.
Becoming an accredited ultrasound practice sends a message to
your patients and the medical community that your accredited
• Meets nationally accepted standards of patient care
• Demonstrates consistent excellence
• Is current with the latest ultrasound technology
• Has met an objective assessment by the most respected
professionals in the field-YOUR PEERS.
The AIUM accreditation process is a realistic and insightful
program focusing on the practitioner's and the patient's needs. The
Ultrasound Practice Accreditation Commission members include
physicians andsonographers representing multiple specialty areas of
For more information, contact:
AIUM, Attn: Accreditation Dept.
14750 Sweitzer Lane, Suite 100
Laurel, MD 20707-5906
Phone: (800) 638-5352 or (301) 498-4100
Fax: (301) 498-4450