Memorandum
Apri1 12, 2001
To:
Jerry Redmon, Procurement Officer
From: John Doe, Business Manager
Subj: Sole Source Justification of Agilent Technologies Echocardiograph System
RQ043927; $245,942; UDAK: 2220100832652021 MUCR
I am writing to you to justify the sole source certification of the purchase of an Agilent
Technologies Sonos 5500 Ultrasound Imaging System ($245,942.00). This
echocardiograph equipment and evaluation station will be used to obtain ultrasonic
images of animal models used in cardiovascular basic research studies. Funding is
provided by the NllI Shared Instrumentation Grant SI0-RRI5723-01 ($291,408; P.I.Michael Zile, M.D.). The current state of the art technology provided by the Sonos
Fusion Imaging System allows us to reliably and accurately assess cardiac function in
small animals such as the mouse. Recent advances in technology have given us the ability
to alter the genetic make-up of animals. Now, in a controlled manner, we are able to
manipulate the expression of genes that we believe are responsible for specific diseases,
and or physiological processes. The mouse has become the animal of choice for these
transgenic and genetic knockout models. Our laboratories have numerous mouse strains
in which we have altered genes that we believe affect cardiac function. The equipment
that we have requested will be used to evaluate cardiac function in several animal model
species, but we have chosen this particular equipment for its superior ability to provide
high resolution images of the mouse heart.
I)
The Agilent Technologies Sonos 5500 with its 15-6L ultraband high frequency
linear transducer is the highest fidelity echocardiograph imaging system
commercially available. In ultrasonic imaging there is a direct and linear
correlation between the frequency of the probe or transducer, and the amount of
detail of the information derived. Higher frequencies allow for more detailed
images. Agilent Technologies highest sensitivity transducer is the 15.6L ultra
band high frequency linear transducer. It produces a frequency of 15J\.1Hz. This
is unmatched by other vendors. Agilent Technologies closest competitor is
Acuson Corporation whose Sequoia 256 Echocardiograph System with 15L8W
Transducer produces frequencies of 14J\.1Hz. While this is an improvement over
the technology of the only two years ago when the maximal frequency available
on commercial units was only 10MHz, it can not obtain the same information
derived from Agilent Technologies 15MHz Transducer. Other vendors such as
ATL and have transducers that only go to the 10MHz to 12MHz range.
Traditionally these are used in vascular labs where human arteries and veins are
analyzed. We use these in mice where the heart is only one-sixteenth of an inch
below the skin. Although the total size of a mouse heart is smaller than a garden
pea, we are still able to measure minute changes in ventricular wall thickness, and
measure ejection fraction and contractile function.
2) In addition to having the highest sensitivity transducers, Agilent Technologies also
offers
several other key features that are not available on echocardiography systems offered
by other vendors. These include the S3 ultraband transducer with 1.3MHz harmonics
which provides myocardial contrast echocardiography and real time perfusion of the
heart. In this particular case the lower the frequency
the better the image. This is because the image is taken of a contrast dye that is
injected into the heart, not the tissue that comprises the heart. Higher frequency
probes interfere with the contrast dye and cause the bubbles that provide the contrast
to create the image to burst. Agilent offers the lowest frequency available for cardiac
contrast dye images. Other vendors supply transducers in the 2MHZ range. Again,
these differences in frequencies provide differences in the quality of the images.
3) The technology that comprises the acquisition phase of the transducers is also
superior in the Agilent Technology system. The transducers are comprised of an array
of individual sensors or processing channels. The Agilent Technology system has 512
digital processing channels while the Acuson and other systems have 256 available.
4) These ultrasound systems use sound waves to produce images of tissue in the same
way that a radar system works. It emits waves of specific frequencies that are
reflected back from objects that it encounters. The higher the decibel level of a
system, the more sophisticated it is. The Agilent Technology system has a dynamic
range of up to range of l50DB vs lOODB for their competitors.
5) Another factor that affects the quality of the image is frame acquisition rate.
Agilent Technologies frame acquisition rate of 300 MHz is the highest commercially
available.
6) Acoustic quantification, color kinesis, dynaniic stress echo and integrated 3-D
acquisition is not provided by other manufacturers. These allow for simultaneous
grayscale and color analysis of echocardiographic data.
7) The unique color compare and m-mode color compare features allow us to see real
time gray scale and simultaneous real time combination of gray scale and color
doppler images.
8) Angio Compare ability to look at grayscale and combination of grayscale angio
images simultaneously. These simultaneous functions are important when trying to
discern cardiac function comparisons between different imaging techniques and are
not available from other vendors.
10) Agilent technologies provides real-time contrast imaging. The power modulation
technique employed by this system allows for the finest myocardial contrast imaging
available today.
The Agilent Technologies Sonos 5500 is the most sophisticated echocardiographic
imaging system available on the commercial market today. For the reasons, listed
above and because we are basing the purchase on how it works in the evaluation of
mouse hearts we have asked that this be treated as a sole source purchase.