Ask the right questions before investing in a DITI
When you're planning to invest in a DITI system. Remember, you're buying
more than just a camera, you're integrating a whole new technology into
your practice. Don't be confused by technical mumbo-jumbo.
The questions you need to be asking are:
--Is the system I am going to purchase really suitable for the application?
--The technology seems to be constantly changing. Will future upgrades
be necessary and at what cost?
--Will the system be economic from a business perspective? (Can the
system make money for me?)
--What's the total cost of ownership for the system?
-------Any high cost maintenance items?
-------Calibration Intervals? Calibration costs?
-------Are there extra charges for ‘peripherals'?
-------Are you charged for Software updates?
-------Are the Doctors interpreting images certified Thermologists?
Who certifies the doctors ?
-------How much does the interpretation service cost?
--Can I get immediate help if I have technical problems?
--Who interprets the images I take?
--How many systems do you have installed in the USA and Worldwide?
--How long have you been selling these systems?
--Can I contact a list of your system users ?
Q. I heard the Meditherm system was manufactured
overseas somewhere. Does that mean I won't be able to get support in
A. First, the Meditherm camera is
manufactured in the USA and is fully compliant as a medical device. Second, factory phone support
is available between the hours of 0700 to 1800 Pacific Coast Time. Outside
of phone support hours, response to e-mail questions is normally within
Q. Can I get financing for the system?
A. We have several leasing
companies we work with. Professionals can be approved within 24 hours.
Non professionals normally need have been in business for 2 years or
more and have a clean credit record. If you're just starting out there
are programs available at slightly higher rates and may require a deposit.
Contact us for details.
Q. What are typical monthly payments?
A. Typical payments will
be under $800/month. Three to four full-body or six to seven Region-of-interest
scans per month will cover the equipment lease costs.
Q. Can I make money with DITI?
A. We have a Microsoft
Excel demo program that allows you to calculate payback based on your
projected costs. Contact us for a free copy.
Q. What is DITI?
A. DITI, or 'Digital
Infrared Thermal Imaging” is an imaging technique for measuring and displaying
body temperature. It is radiometric; it measures temperatures. It relies
on the principal that all objects at a temperature above 0 ° K
(absolute zero) radiate infrared energy. The amount of radiation is
of the body's physiology. Meditherm's DITI camera captures and records
this energy and converts it to an image that can be viewed on a computer.
Temperature data is digitized and retained for analysis and archiving.
Q. Why doesn't the Meditherm camera measure
from 0 to 300° C?
A. Because we have optimized
for sensitivity within the range of human physiological temperature.
Q. I hear from some people that you need
to "cold stress" the patient. What is "cold stressing?
Do I really need to do it?
A. Cold stressing is a
test to measure sympathetic function, It is a useful test for a number
of conditions including RSD (CRPS). Protocols used with the Meditherm
system for breast screening do not require routine cold stressing but
it may be requested by a referring physician or reading thermologist.
Q. I was told that grayscale thermograms were higher resolution than color, why don't you show grayscale ?
A. Nowadays there is no difference in
resolution between color and grayscale with modern digitized images.
When images were viewed on an old TV screen, it took three phosphors
on the cathode ray tube to make one color dot….. it only takes
one phosphor to make a shade of grey, the resolution in black and white
therefore, would be three times greater than it was in color.
Q. What is the difference between high definition thermography and other types ?
A. Just about all modern cameras provide
high-definition images. The ‘definition’of a thermogram
relates to how many individual temperature measurements are taken to
build the image. The actual definition is not as important as how accurate
and sensitive those temperature measurements are. The higher the definition,
the better the picture will look but this does not mean that the accuracy
is any better.
Describing a thermogram as ‘high definition’maybe confusing
and misleading as most so-called high-definition images are produced
by software manipulation of the data.
Low definition would be considered below 160 x 120 pixels. Industry
standard is between 160 x 120 up to 320 x 240 pixels. High-definition
would be considered above this and can be as high as 640 x 512 pixels.
Q. Why do I need to come back in three months for another breast study ?
A. The most accurate result we can produce is change over time. Before we can start to evaluate any changes, we need to establish an accurate and stable baseline for you. This baseline represents your unique thermal fingerprint, which will only be altered by developing pathology. A baseline cannot be established with only one study, as we would have no way of knowing if this is your normal pattern or if it is actually changing at the time of the first exam. By comparing two studies three months apart we are able to judge if your breast physiology is stable and suitable to be used as your normal baseline and safe for continued annual screening.
The reason a three-month interval is used relates to the period of
time it takes for blood vessels to show change…… a period of time less than three months may miss significant change……..
a period of time much more than three months can miss significant change
that may have already taken place.
There is NO substitute for establishing an accurate baseline. A single study cannot do this.
Q. Everybody talks about resolution.
What is resolution? Is resolution important?
A. First, there are a
couple of resolutions that apply to IR cameras. There's spatial resolution
and there's thermal resolution. Spatial resolution is related to the
number of pixels in an image. This is analogous to today's digital cameras
and their number of pixels/picture, e.g. 2 megapixel vs. 3 megapixel
vs. 4 megapixel, etc. For many or most applications 2 megapixels will
provide excellent pictures for most settings in fact unless you try
to zoom in you would be hard pressed to tell the difference between
2, 3 or 4 megapixels. However, you will find a significant difference
in image file sizes and camera costs. The point here is that the 2 megapixel
camera will work perfectly well for routine picture taking. Using IR
cameras for scanning humans works much the same way. The human body
doesn't exhibit significant temperature changes over very small areas.
The skin tends to form a continuous surface and heat spreads out smoothly
over large areas. In fact research has shown that good pattern recognition
could be performed with IR cameras having resolutions as low as 160
pixels by 160 pixels ( total pixels~26,000).
Thermal resolution is a measure of a camera to detect very small temperature
differences. Say for example one wanted to see 0.25 ° C differences
on a surface, you would need a camera capable of detecting much smaller
differences. As a practical matter, the human body has a typical surface
temperature ranging from just over 30 ° C to around 38 ° C.
Temperature variations on an individual will fall into that range of
temperatures. Meditherm cameras are optimized for viewing this temperature
range. The color scale is set so that maximum contrast can be achieved
to show findings that relate to pathologies that would not otherwise
Want smooth images- use 256 color steps.
Want maximum contrast use 8 degree C range and 16 color steps.
Meditherm's extensive testing protocols are designed to work with the
8 degree thermal window and 16 colors of the 'Medical Map'.
Q. Is system stability important?
A. Yes! Stability is
the characteristic in a system that allows you to accurately perform
studies over time …. (minutes / hours / weeks / years) to detect
any changes . It is because the Meditherm camera has such excellent
stability that screening breast studies can be performed with confidence;
it is due to this stability that certified thermologists (MD's) can
reliably analyze images statistically and provide reports to the thermographer.
Q. I notice some IR cameras use many
more colors in their displays. How come Meditherm only uses 16?
A. We do give you the
choice of many different color displays including the ‘smooth'
looking 250 color scale. Our default color scale uses 16 colors that
make visual identification of temperature differences easier and enhances
Q. I recently saw a camera that had a
real fast scan. Yours doesn't. What's the difference between that one
and the Meditherm DITI?
A. There is a trade off
between speed and sensitivity / accuracy which applies to all systems.
The Meditherm Pro system uses two scanning speeds that give the best
combination of speed, sensitivity and accuracy so you don't have to
pay for speed that you don't need! The Meditherm IRIS system does deliver
real time speed (30 frames per second) and provides sufficient sensitivity
for medical imaging.
Q. What's the difference between a scanning
camera and a focal plane array camera?
A. There are several broad
categories of imagers. They can be lumped into groups as follows:
Single detector/scanning systems, scanned/linear array and staring
or focal plane array. Each has characteristics somewhat unique to itself,
but each can be made to read temperatures (radiometric).
Scanning systems use a single detector and have a scanning mechanism
in the optical path which allows an image to be constructed. A major
benefit to this approach is that the single element is making all the
measurements. Differences in element sensitivities or bad elements,
which occur in focal plane array devices, don't occur thus thermal uniformity
is quite good. The downside to scanning cameras is they take longer
to image, but for stationary objects where temperatures aren't changing
rapidly (as with medical imaging) this is a non-issue.
Focal Plane Array or staring array cameras (FPA's) have the benefit
of providing fast scanning. Images are formed in "real-time".
Each element in the detector array corresponds to a pixel element in
the displayed image. Until recently, FPA's required cooling to be useful.
Liquid nitrogen was used for a long time. Today closed cycle Sterling
Coolers are frequently employed. Downsides to these cameras are expensive
replacement cost for coolers and the fact that there are dead pixel
elements and different sensitivities across the detector which must
be compensated for (or assigned a value).
A new type of FPA, one that doesn't require the Sterling cooler, is
becoming more popular. This is known as the micro-bolometer. It has
the same issue with dead or lower sensitivity elements.
This type of detector is really a hybrid of the other two. It uses
a linear array, offers higher scanning speed than the Scanning detector,
but considerably slower than the Focal Plane Array detectors. To some
degree it suffers from the bad pixel syndrome but since there are fewer
active elements it's a smaller issue. It also needs a cooler, which
can be a costly maintenance item.
The third style, the linear array, uses a line of detectors which are
scanned. This is a cross between a scanned single element and a focal
plane array. It provides marginally faster scans but also has some of
the same bad pixel issues. Currently, linear array cameras use detectors
that require mechanical coolers or use Liquid Nitrogen as the cooling
element. Images, after averaging, can be quite good.
Both FPA's and Linear array cameras have noisier displayed images and
are generally averaged before saving an image. Signal averaging ads
to the overall acquisition time thus reducing the seeming advantage
over scanning systems.
Q. Who certifies your thermographers?
A. Meditherm provides
technician training courses that are approved by the American College
Q. Do I have to be a doctor to operate
A. No. Anyone with computer
skills can be trained as a thermography technician.
Q. How long does it take to learn to
A. Firstly, there is no
necessity for learning to interpret images. With the Meditherm system
you have access to an online interpreting service that is staffed by
fully certified MD's. If you do wish to interpret and report images,
Thermology courses are conducted by the American College of Clinical
Thermology, 300 hours is required for board eligibility.
Q. What is thermal drift ?
A. Thermal drift refers
to the fluctuation of temperature measurements in most industrial cameras.
This can be caused by many contributing factors but is most often related
to uncooled technology; no reference point! Medical DITI must have
stability for comparison of contralateral images and for change over
time. Thermal drift takes the accuracy and sensitivity down to levels
that are not acceptable for medical applications. Thermal drift can
also be caused by poor quality detector cores and startup stabilization
Bottom line: the absolute temperature being recorded may change up or down by whatever the drift factor is.
Meditherm developed a stable reference point within the camera that is used to calibrate each and every temperature measurement to a sensitivity of 1/100th of a degree C. (0.01░C). This solved the problem of thermal drift in Medical Applications. If we had to give a figure I would say 0.01░C to no drift.
Please contact us with any other questions we can add to this list. firstname.lastname@example.org