Options in technology from major manufacturers are expanding the
capabilities of lower-end scanners, reducing the compromises that
users make when they buy equipment on a budget. For example, Aspire
Continuous ImagingTM (CI) technologies, which enable radiologists
to view an x-ray computed tomography (CT) study as it's acquired,
are now available on the Xpress and Xvision Series CT scanners from
Toshiba America Medical Systems, Inc. (Tustin, CA). "As new, more
efficient technologies become available, we intend to offer options
and upgrades," said Charles Corogenes, director of the CT Business
Unit at Toshiba.
Aspire CI includes SureStart, a technology that allows scanning
to be delayed until the contrast agent arrives at the region of
interest. According to Toshiba, this capability results in
high-quality images with up to 25% less contrast, a significant
potential cost savings.
Moving interventional procedures from surgery to
"We believe this technology will move many of the guided
interventional procedures from the operating room into the
radiology department because they can be performed more quickly,
less invasively and, therefore, at lower cost," said Mr. Corogenes.
(Several of the CT technologies mentioned in this column could
become valuable tools for interventional applications, which will
be covered in more detail in the July 1998 Applied Radiology, a
special focus issue on interventional radiology.)
Toshiba also has new CT technologies that are works-in-progress,
including a movable CT gantry for use in a surgical CT system, and
an upright CT-both capable of helical scanning, according to the
In the surgical CT, the self-propelled gantry travels in the
axial direction so it can be used with a standard surgical table in
an operating room or other specialized location. "This system could
be particularly beneficial in the emergency room when you need to
obtain a high-grade scan quickly and then move the scanner out of
the way," said Mr. Corogenes.
The upright CT, with the gantry suspended from the ceiling, is
built horizontally to facilitate localization of tumors that will
be treated with heavy-ion radiation beams. "The ion accelerator
beams are horizontal, and the patient is treated in the sitting
position," said Mr. Corogenes, adding that the CT device provides
for more accurate treatment planning and delivery.
Suite of CT options
Picker International (Cleveland) recently introduced a group of
options, called VenueTM, for x-ray computed tomography. Venue is
designed to expand the CT suite beyond diagnostics to include
One option with Venue is FACTSTM (fluoro-assisted computed
tomography), a c-arm fluoroscopy x-ray unit that allows minimally
invasive imaging procedures to be performed in the CT suite. This
ability adds convenience and saves time by eliminating the need to
transport patients to a separate room to perform an invasive
According to Picker, FACTS was the only solid-state fluoroscopy
system available when it was introduced at the 1997 Radiological
Society of North America (RSNA) meeting. It includes an integrated
flat-panel detector, which can be positioned between the CT gantry
and patient couch, that uses a new amorphous silicon flat-panel
photodiode array. The array is "light and compact," according to
the company, unlike other c-arm fluoroscopy systems that contain
large, heavy intensifier tubes that may be awkward to position.
Another option with Picker's Venue, C-ViewTM, is a new c-arm
rail-mounted on the ceiling for positioning on either side of the
CT scanner (figure 1). The "slide back" couch can be used for
routine CT imaging or can be pulled back for angiography
C-View features a high resolution digital imaging system,
according to Picker, with real-time edge enhancement, digital spot
capability, road-mapping, and multi-image display.
Digital x-ray detectors
Also at the 1997 RSNA, GE Medical Systems (Milwaukee) announced
an agreement with EG&G, Inc., to manufacture a
"first-of-its-kind, multi-purpose" digital x-ray detector. The new
system replaces conventional x-ray film and chemicals with computer
images that can be stored and sent electronically. There also is a
potential use for computer-aided detection of abnormalities with
these digital x-ray images.
The new detector will form the basis of a new family of GE x-ray
products, complemented by networking and archiving options. "The
digital detector is the product of one of GE's biggest and most
long-range R&D efforts ever. Its 10-year, $100-million
development has involved more than 100 scientists and engineers and
has resulted in nearly 80 patents," said Lewis S. Edelheit, senior
vice president for Corporate R&D at GE.
"This technology gives us the unique ability to make full-sized
detectors in one piece, which differs significantly from other
approaches that combine several smaller detectors to make a large
one," said Mr. Edelheit. "Detectors based on GE's large-area
technology will serve the whole spectrum of x-ray applications,
from mammography and radiography to real-time fluoroscopy and
angiography," he added.
The digital x-ray detector currently is undergoing clinical
investigation at mammography and radiology sites, including
Massachusetts General Hospital, the hospitals of the University of
Massachusetts and University of Colorado, and the Hospital of the
University of Pennsylvania. "In preliminary trials, the prototype
digital mammography system is producing quality images with all the
benefits of digital imaging," said Dr. Daniel Kopans, director of
the Breast Imaging Division at Massachusetts General Hospital.
Faster CT scanning, thinner slices
GE also introduced two technologic advances that result in
faster CT scanning and thinner slices. With SubSecond Scanning for
the ProSpeedTM CT scanner, users can obtain greater helical
coverage per breath-hold or 20% shorter scans, according to GE.
With SmartHelicalTM for the HiSpeedTM CT/i scanner, users can
reduce the dose of contrast medium by 33%, according to the
company. SmartHelical also reduces mA, allowing users to perform
longer helical runs with thinner slices. According to GE,
physicians can obtain 3-mm slices in the same amount of time
required for 5-mm slices with standard helical scanning. "A
standard helical scan that might be done at 300 mA for 30 seconds
could be done with SmartHelical at 200 mA for 75 seconds, a 150%
increase in helical coverage," explained GE.
C-arm systems with isocentric design
Siemens Medical Systems, Inc. (Iselin, NJ) now offers three
c-arm systems featuring isocentric design. Isocentricity means that
the c-arm's location does not require readjustment when the
rotational projection angle is changed, explained Siemens, which
can reduce patient and operator x-ray exposure and save examination
The SIREMOBIL® Iso-C is designed for a broad range of operating
room applications. The POWERMOBILTM series features a 20-kW
generator and high frame-rate pulsed fluoroscopy for such
procedures as coronary angiography and minimally invasive
cardiosurgical interventions. The ARCOSKOP® is designed for trauma
and emergency room applications.
Expanding range of fluororadiography
Siemens also introduced QuattroVision imaging, with a 2048 ¥
2048 pixel matrix and a 10-bit gray scale, for its FLUOROSPOTT
T.O.P. digital fluororadiography system. This technology expands
the application of fluororadiography to include skeletal and
thoracic diagnostics, according to Siemens.
A new generation radiology information system (RIS) was recently
introduced from Per-Se Technologies (Atlanta). The ProgRIS 98
release features advanced capabilities such as a web-enabled report
browser that gives referring physicians access to reports from any
internet-connected computer, at any time, without installing
The three-tiered client/server architecture improves remote
access for physicians and transcriptionists, according to Per-Se.
In addition, two-way communication between ProgRIS 98 and picture
archiving and communication systems (PACS) support the tracking of
image histories. The ProgRIS 98 also incorporates voice recognition
ProgRIS 98 runs on a Windows 95 or Windows NT client with NT or
UNIX servers and an SQL-compliant relational database. The system
is designed for single and multi-site hospitals and imaging center
The company also offers an optional Mammography Information
Reporting and Tracking module, fully integrated with the base
ProgRIS. This module features direct or check-list entry of
mammographic findings, automated patient report generation,
tracking of patient medical history, and recommended follow-ups,
pathology results, and statistical reporting. According to Per-Se,
the module is based on the American College of Radiology (ACR)
BI-RADS [Breast Imaging Reporting and Data System] standard and
complies with all applicable ADR, MQSA, and Medicare
Consumer electronics companies continue to grab more of the
medical imaging market. The Medical Systems Division of Sony
Electronics, Inc. (Montvale, NJ), for example, recently introduced
two high-resolution, black-and-white thermal printers designed for
radiology, ultrasound, and the cardiac catheterization lab.
The UP-980, a Multiscan® video graphic printer, incorporates an
advanced thermal print head and offers 256 gray-scale control,
according to Sony. The printer features two frames of memory and a
selectable multiple print mode that allows for printing two, four,
or six images per sheet. The UP-960, also featuring 256 gray
levels, is an international model. Both printers accept NTSC and
The company now provides a blue transparency medium for the
UP-980 for printing black-and-white images on transparent film,
designed for radiology applications that require "quick reference,"
such as sports medicine, c-arm imaging, and ultrasound.
Medical computer display
Sony has also introduced its first medical computer display.
Developed for patient monitoring applications such as bedside
display or central monitoring in the operating room, the
PGM-100P1MD features a variable resolution of 640 x 480 to 1280 x
1024 dots. The monitor incorporates Multiscan capability, and an
"anti-reflection coated" Trinitron® cathode ray tube (CRT) that
clearly displays information in brightly lit environments,
according to Sony. The display's "splash-proof" cabinet is designed
to protect the system from liquid spills.
Still image recorder
To enable medical images to be stored digitally on a 2-3/4" data
MiniDisc, Sony has developed a digital still image recorder. The
DKR-700/1 receives analog or digital signals of black-and-white or
"Though medical procedures currently are being recorded on
videotape, more and more of the medical community is using digital
mediums to archive, transfer, and present this information. With
the DKR-700/1, Sony provides the ideal system to transform video
into a digital format," said Jim Sandy, vice president of medical
systems for Sony Electronics' Business and Professional Group.
According to the company, the DKR-700/1 can digitally store and
play back from 100 to 1,000 still images of standard NTSC video on
a single 140-megabyte data MiniDisc. Images also may be retrieved
from the disk by an appropriately configured personal computer.
Anticipating the much-dreaded year 2000 problem for computer
systems (generally programmed to interpret "00" as the year 1900),
GE Medical Systems (Milwaukee, WI) announced in March that it has
developed a program to help its customers avoid this problem in
their radiology equipment.
"Year 2000 is an issue that we have taken very seriously," said
Jeffrey R. Immelt, president and CEO of GE Medical Systems. "We
have anticipated this issue for some time and are offering a
Year-2000 warranty on new system purchases. We've also committed
ourselves to providing software updates on currently manufactured
systems at no charge to our customers," he explained. For older
systems that are no longer manufactured by GE, the company said it
would offer either a software solution or "functional workaround."
GE's Year-2000 updates will be available over the next 18