HERMES
RAPID (Run Anywhere Patient Image Display)
HANDBOOK
Version
2.2
Document Revision Date:
22-January-2008
Document Number:
CD-P0103-0500-06
0413
K002782
Nuclear Diagnostics AB
Skeppsbron 44
S-11230 Stockholm, SWEDEN
Tel: +46 (0)8 190325
Fax: +46 (0)8 184354
HERMES Medical Solution 305 Mary
Beth Drive • Greenville, NC • 27858
Telephone (866) HERMES2 •
Facsimile (360) 604-1940
Info@hermesmedical.com
Nuclear Diagnostics Ltd.
Unit E1 Springhead Enterprise Park
Northfleet, Kent DA11 8HH, UK
Tel: +44 (0)1474 328728
Fax: +44 (0)1474 328718
www.hermesmedical.com
RAPID
 2005 Nuclear Diagnostics
The software described in this manual and the software itself is copyrighted and all rights are
reserved by Nuclear Diagnostics. Neither the software nor the manual may be copied or in
any other way reproduced without prior consent in writing from Nuclear Diagnostics, who
reserve the right to make changes and improvements to the software and the manual at any
time.
Nuclear Diagnostics assumes no responsibility for loss of data.
Nuclear Diagnostics assumes no responsibility for any results and diagnoses
derived from using the program described or from information in this manual.
The users of the software are solely responsible for its use and for all resulting
diagnoses.
Nuclear Diagnostics welcomes feedback from readers of this manual. Please report any
errors in content or typography and suggestions for improvements by E-mail
E-mail: hermes@nud.se
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Table of Contents
Table of Contents...................................................................................3
Introduction ............................................................................................6
RAPID for CD ............................................................................................ 6
RAPID for PC ............................................................................................ 6
Input Data ...............................................................................................7
Reading patient study list .....................................................................7
RAPID for CD ............................................................................................ 7
RAPID for PC - reading the HERMES WORKING directory.................... 7
RAPID for PC - reading a DICOMDIR CD................................................. 7
RAPID for PC - reading studies with JADE............................................. 7
Selecting Studies to View......................................................................7
The Main RAPID window .....................................................................10
Protocols .................................................................................................11
Loading new study..................................................................................11
Snapshot Save ........................................................................................11
Study Information....................................................................................12
Print..........................................................................................................12
Help ..........................................................................................................12
About........................................................................................................13
Colour / Threshold Limits .......................................................................14
Display Options....................................................................................16
Zoom ........................................................................................................16
Pan ...........................................................................................................16
Reset ........................................................................................................16
Full View ..................................................................................................17
Cross Hairs..............................................................................................17
TCS Mode ................................................................................................18
TCS Display ..................................................................................................... 18
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Zooming ........................................................................................................... 19
Vertical TCS Display ........................................................................................ 20
Non-TCS Mode ........................................................................................23
Transverse Display .......................................................................................... 23
Coronal Display................................................................................................ 25
Sagittal Display ................................................................................................ 26
Two Study Mode......................................................................................27
Study View 1/2 ................................................................................................. 27
Align ................................................................................................................. 29
Fusion .............................................................................................................. 30
Volume of Interest (VOI) options ........................................................31
Creating a VOI .........................................................................................31
Pixel values for a pixel or VOI ................................................................32
Growing a region within a VOI................................................................32
Limitations regarding the use of SUVs..................................................34
Tools Page............................................................................................34
General.....................................................................................................35
Local Preferences ............................................................................................ 35
Honour window/level hints ............................................................................... 35
Honour CT window/level hints ......................................................................... 35
New Patient in New Instance ........................................................................... 35
Window Size Option......................................................................................... 35
Window Background ........................................................................................ 35
SUV Option ...................................................................................................... 36
Threshold/Colour Options ................................................................................ 36
Which Control at Start ...................................................................................... 36
VOI Calculation Option .................................................................................... 36
Layout ......................................................................................................37
TCS Layout ...................................................................................................... 37
Cross options ................................................................................................... 37
Order of Images ............................................................................................... 38
Contour Format ................................................................................................ 38
Movie........................................................................................................38
Movie layout ..................................................................................................... 38
Colour Selection Option .................................................................................. 38
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On/Off Options ................................................................................................. 38
Generation options........................................................................................... 38
Print..........................................................................................................38
Protocols .................................................................................................39
CT Window/Level.....................................................................................39
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Introduction
This program displays tomographic data, MIP movie data and screen captures.
Registered pairs of studies, from the same or different modalities, for example PET/CT
and SPECT/MR, can be displayed at the same time and fused.
RAPID comes in two versions:
RAPID for CD
This version of RAPID is primarily designed to allow patient data to be viewed on a
standard Windows1 based PC, without requiring access to a HERMES workstation. This
is accomplished by burning both the RAPID program and the patient data onto a CD on
a HERMES workstation. The patient data is encrypted and the user is required to enter a
password before the studies can be viewed. After inserting the CD in the PC, the RAPID
program runs automatically, firstly displaying a list of patient studies copied to the CD.
This version of the program can only be run from CD.
RAPID for PC
RAPID for PC is installed as an application on a Windows1 based PC and can read
studies in three ways:
•
From a DICOMDIR CD
•
From the WORKING directory of any HERMES system, using a mapped network
drive. This functionality is provided by the Samba file sharing software, installed on
the HERMES system.
•
Using the JADE software, supplied by Hermes Medical Solutions
For accessing studies from a DICOMDIR CD and from WORKING, Rapid is installed
with shortcuts, configured to access the appropriate drive automatically.
RAPID for PC is locked to a particular PC and needs a password from Hermes Medical
Solutions.
When running RAPID from a CD, or when running as a PC application and loading
studies from a DICOMDIR CD, you may experience delays in executing various
functions of the program. This is due to the memory limitations of your computer and/or
the speed at which your computer reads the CD.
The images in this handbook may appear different from those on your screen. This is
because you may be running a different version of the program or because the
configuration of your program is different from that used to produce this handbook.
1
RAPID has been tested on Microsoft Windows NT, 2000 and XP. The program will
not run on Windows 95, 98 or ME
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Input Data
The studies read in RAPID can be in Interfile, DICOM or ECAT format. Three types of
study can be loaded:
•
•
Transverse reconstructed studies
Screen captures (graphics images)
Reading patient study list
RAPID for CD
Insert the CD into the CD drive on the PC. The CD should start loading automatically. If
it does not, double click on the icon for the CD drive in My Computer and double click on
the RAPID icon. As the program loads, an information window will appear and you will
be asked to enter the password for the disk. Click on OK after you have entered the
password. The Patient Selection window will then appear.
Note
Passwords are specific to individual RAPID CDs and will be automatically saved by your
computer for up to 14 days after you use the CD for the first time. This means that you
can use the CD for up to 14 days after initial use without having to re-enter the
password. If you wish to access study data from the CD after 14 days, you will be asked
to re-enter the password.
RAPID for PC - reading the HERMES WORKING directory
Click on the appropriate shortcut RAPID Working. RAPID will read the index of patient
studies on the networked HERMES system automatically, and the Patient Selection
window will then appear.
RAPID for PC - reading a DICOMDIR CD
Insert the DICOMDIR CD and click on the shortcut for the RAPID CD. The Patient
Selection window will then appear.
RAPID for PC - reading studies with JADE
Please see the JADE manual for a description of how to read studies using JADE.
Selecting Studies to View
You can choose which studies to view in the Patient Selection window. The far left
column lists all of the patients with studies on the CD or in WORKING. Click on the Open
All button at the top of the window to reveal the individual studies available for all
patients. Alternatively, you can view the studies available for one single patient by
clicking on the ‘+’ located to the left of the patient’s name. Next, select the individual
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studies you wish to view by clicking on each (you can deselect these using the Clear All
button).
The order in which studies are selected determines the order in which they are
displayed. If radiological (CT or MR) and PET or SPECT studies are being displayed
together, select the radiological study first.
The column width can be adjusted by dragging the separator between the Labels. For
example if the Organ field is too small, drag the border between the Organ and Label
fields with the mouse button held down.
Open All Open all patient folders and show all studies.
Close All Close all patient folders
Clear All Deselect all folders/studies
Cancel Terminate selection and Rapid, if this is the initial search.
Doc … Display this PDF manual in Acrobat. The Acrobat Reader must be installed for
this to work.
The field Type has a character for each data type that exists in the folder, T(ransverse),
M(IP) and P(rint). The folder with the name PET KCPC in the example above has one or
more studies of each data type supported,
After you have selected the studies you wish to view, click on the
button to start the program. As the selected studies are loading, you may be asked if you
want the program to create MIP projections (movies) from the slice data.
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If 2 studies have been selected, and the pixel size and/or slice separation of the 2 are
different, a popup window will appear to indicate that the second study will be resampled
to match the first study. This means that the pixel size and slice separation of the
second study are adjusted to match the first study. The original resolution of each study
remains the same.
The RAPID program assumes that the 2 studies are registered, either because they
have been acquired at the same time (PET/CT) or because they have been registered
using the HERMES Multimodality or similar registration program.
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The Main RAPID window
The main window for RAPID, displaying a single study, is shown below. Three or four
images are displayed per study: three if only a volume study has been loaded and MIP
movies were not requested, and four if a complete dataset (volume and movie) has been
loaded, or a volume study has been loaded and MIP movies requested.
The layout of the main window, the colour tables and thresholding type and many other
options can be set in the Tools page of the program, which is described later in this
document. It is recommended to select the preferred settings and then to save a protocol
and/or save the preferences of the program.
Main window, displaying a complete tomographic and movie dataset. From left to
right are the coronal, transverse, sagittal and MIP movie images
Shows version and build date of the RAPID program.
Note
This logo is only shown if the screen size is set in the Tools page to 1024*1280 or larger.
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Protocols
A predefined protocol can be selected from the list box in the top left corner of the main
window (PET-CT in this example).
It is recommended to create protocols for each study type e.g. PET only, PET and CT,
PET and MR, PET and PET, as each will require different colour table and threshold
settings.
If RAPID is always used for the same study types, it is sufficient to click on Save
Preferences in the Tools page, and the program will then load these preferences when it
starts.
Preferences and protocols are not read or saved with Rapid for CD.
Loading new study
Shows the patient selection window. Depending on the property setting, either the newly
loaded studies will overwrite the current ones, or a new instance of Rapid will be
started.
Snapshot Save
Saves the current window as a bitmap image in the selected directory.
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Study Information
Shows a popup window with patient- and study-related information. The study-related
information includes the radiopharmaceutical used, the dose administered and other
header information (example shown below).
Print
Prints an image of the application window.
Help
Displays this on-line manual. This requires the Acrobat reader to be installed on the PC.
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About
Shows version and build date of the RAPID program.
If a software problem report is sent to Hermes Medical Solutions, the information in this
message should be included.
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Colour / Threshold Limits
The Colour and threshold adjustment controls are located in the left panel of the window
near the bottom.
The units of the threshold sliders can be set in the Tools/General window to percentage,
pixel value, window/level MR or window/level CT. A number of CT presets can be set in
the Tools/CT Window/level window. The CT presets can be changed by right clicking
over either of the Colour/threshold sliders.
The Colour and thresholds can be adjusted separately for the TCS display and the MIP
movie display, provided the Separate Movie Colour Table option is set in the Tools page.
An example of each is shown below. You can switch from one to the other by simply
selecting the appropriate tab (TCS or Movie).
TCS Colour/threshold limits (Pixel Value) - two studies loaded
Movie Colour/threshold limits (Pixel Value) – two study loaded
Some controls may not be displayed, like the Fusion controls with only one study loaded.
So will the Movie tab be disabled if no MIP movie is generated. When more than one
study is loaded, a Fusion control button also appears in this window.
The Colour tables and window/level or threshold settings used while in fusion mode are
independent of those used in non-fusion mode, so these should be set as required and
the preferences saved in the Tools page, or a protocol created and saved.
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Note
If the header of a study has information about window/level type and settings, and the
Honour WL Settings and Honour CT WL Settings are set in the Tools page, these will be
automatically set in the Colour/thresholds limits window when a study is loaded.
For CT studies, the image pixel values represent Hounsfield units, provided the study
header has information to say it is imaging Modality CT. If this is not the case, the pixel
values and level setting will be 1000 larger than would be expected for CT studies.
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Display Options
There are several options for displaying different orthogonal slice views side-by-side
(TCS Mode) or for displaying single views (Non-TCS Mode).
When a single study is loaded, transverse slices are displayed with the number of slices
and slice separation specified in the study header. Coronal and sagittal slices are
displayed with number of slices equal to the matrix size of the study and slice separation
equal to the pixel size specified in the study header.
When two studies are loaded, the scaling (determined from the pixel size) and slice
separation of the second study are adjusted to match the first study. The original
resolution of each study remains the same.
In TCS Mode, transverse slices for both studies separately and for fused studies, are
displayed with the number of slices and slice separation of the first study, so the number
of slices for both studies will be the same. However, coronal and sagittal slices are
displayed with number of slices equal to the study matrix size, whether the studies are
displayed together or separately. Thus a 512 matrix study will have 4 times as many
slices as a 128 study. As a consequence, when two studies of different resolution are
displayed together and you move through the slices, the images and corresponding slice
numbers of one study may be updated and incremented more slowly than the other, as
the higher resolution study will have more images.
In Non-TCS Mode, transverse studies are displayed with number of slices and slice
separation of the first study. Coronal and sagittal slices are displayed with the scaling of
the first study and with number of slices equal to the matrix size of the study with the
lowest resolution. Thus if a CT-PETstudy pair are loaded, the PET study will have the
lower resolution and will determine the slice separation.
For all display options except vertical TCS display, there are additional options which
can be selected by right clicking the mouse button over the image on which the
operation should be applied, or by holding the CTRL or SHIFT keys and dragging with
the left mouse button depressed.
Zoom
Hold the SHIFT key and drag with the left mouse button depressed, to zoom all the
images currently being displayed.
Not applicable to vertical TCS mode, for which a single right click over an image will
zoom to full screen.
Pan
Hold the CTRL key and drag with the left mouse button depressed, to pan all the images
currently being displayed.
Not applicable to vertical TCS mode.
Reset
Select this menu option over any image to reset the image zoom and pan to the original
values.
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Not applicable to vertical TCS mode.
Full View
Select this menu option over an image to zoom the image to full screen. Left click to
return to normal size. Not applicable to TCS and vertical TCS modes. The vertical TCS
has a Full screen viewer. More in that section
Cross Hairs
The style of crosshairs used to triangulate in TCS mode can be changed by right clicking
over any of the displayed images. The choices are, Full Cross, Incomplete Cross, Partial
Cross, or No Cross. The style can also be changed by typing the respective shortcuts
F,I,P or N on the keyboard.
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TCS Mode
TCS Display
This option displays single T, C and S slices and a movie, if required. Click on the TCS
button to display TCS slices together horizontally.
TCS display, showing the coronal, transverse, sagittal and MIP movie views
The order in which the slices are displayed can be changed in the Tools/Layout page.
Triangulating the T, C and S images
The T, C and S images can be triangulated by clicking over any point on any image or
by dragging the center of the crosshairs to a new location. The other two orthogonal
slices will be updated accordingly. As the crosshairs are moved, the pixel count value is
displayed to the left of the main slice display. For PET studies the SUV value for that
pixel is displayed, provided the option to display SUVs is selected in the Tools page.
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The style of the crosshairs can be changed by right clicking over any of the displayed
images, or in the Tools/Layout page.
If two studies have been loaded, and both studies are displayed, the two studies will be
triangulated in synchrony. If only one study is being viewed, the triangulation position will
remain the same as the study view number is changed.
If either the C, S or T display option is invoked, the first slice displayed will be that of the
last triangulation position.
Moving through the slices
The three single slice images and the MIP movie can be stepped through manually or
played as continuous-motion movies. The controls for moving through slices are located
at the bottom of the window. Each set of controls corresponds to the slice display
immediately above it.
Slice
number
Manual slice
control
Stop
movie
Start
movie
Movie
Speed
Zooming
Adjusting the Images Per Row option will change the number of images displayed per
row on the screen and thus the size of the images.
To zoom all the images currently displayed either:
• use the Zoom control on the main page
• hold the SHIFT key and drag with the left mouse button depressed – up to zoom
out and down to zoom in.
MIP
If two studies are loaded and the MIP’s are created the MIP movie can show a fusion of
the two MIP’s. The controls for Opacity and Fusion On/Off works exactly the same way
as for the controls for slices with Fusion.
To save a MIP (with or without Fusion) right click on a MIP, Select Save Movie as
MPEG. A file name box is shown, enter the name and folder to save the file. Do not add
the .mpeg extension, will be done automatically.
For this to work the imagemagick package must be installed, See Install manual.
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Vertical TCS Display
Reference
Image
Slice number control
(use this to view other slices)
Vertical TCS display, showing (from top to bottom) the transverse, coronal and
sagittal views
This will display TCS slices together vertically for a single study at a time.
Triangulating the T, C and S images
The T, C and S images can be triangulated by clicking over any point on any image or
by dragging the center of the crosshairs to a new location. The other two orthogonal
slices will be updated accordingly. As the crosshairs are moved, the pixel count value is
displayed to the left of the main slice display (shown below). For PET studies the SUV
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value for that pixel is displayed, if the option to display SUVs is selected in the Tools
page.
The crosshairs are always displayed as a full cross and cannot be changed.
If two studies have been loaded, triangulation for the two studies is independent.
Moving through the slices
You can move through the slices by clicking on the reference image to the left of each
series or by clicking the arrow keys above each reference image.
Zooming
Adjusting the Images Per Row option will change the number of images displayed per
row on the screen and thus the size of the images.
To zoom all the images currently displayed, use the Zoom control on the main page.
To zoom an individual image to a full screen display, right click over the image. Left click
to return to the main display page.
Full screen display
Rapid can show a full screen (FS) large image of each of the image orientations T/C/S. It
will also remember the positions where a FS image was last placed. This is mainly of
importance for systems with multiple screens, where the physicals screens (monitors)
constitute one large “screen”.
As mentioned above Right click on an image in the vertical TCS will popup the FS
image. It has a small set of controls to set thresholds, colour and slice.
When launched it inherits the settings form the vertical TCS image, but can the
independently be modified and the vertical TCS threshold are left untouched.
Each right click creates a new FS window; an already existing window will not be
replaced.
For example you want to display in full size slice 45 and slice 46, just first right click on
slice 45, navigate in the vertical TCS to slice 46 and a new right click. Move one window
out from the other and if you have a multi screen system you can view and manipulate
thresholds independently.
To close a FS window, right click in it or hit the Escape key.
Note: The FS window does not support Fused images
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Patient Name
and ID
Change Slice.
Up/Down arrow
or the scroll
wheel can be
used to change
slice
Slice Info
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Change Colour
Threshold settings. Can be Pixel
Value or Window/Level
Depending on main Colour mode
setting
Window Level info
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Non-TCS Mode
Transverse Display
Image, Add and Step
controls
Transverse slice display
Images per row
Moving through the slices
In this mode, you can view new slices by any of the following methods
• using the Image control (change the slice number or click the arrows to view new
slices),
• clicking on the reference image to the left of the main display
• using the scroll button at the right of the screen.
Summed images can be created using the Add control (select the number of slices you
wish to combine in each image). The Step control is automatically set to the same as the
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Add control, but can be changed independently if required. The Step control determines
whether there is overlap between the summed slices.
For example, if Add is set to 2 and Step set to 2, the sequentially displayed slices will be
1-2, 3-4, 5-6 etc. If the Add control is set to 2, and Step to 1, the displayed slices will be
1-2, 2-3, 3-4 etc.
Zooming
Adjusting the Images Per Row option will change the number of images displayed per
row on the screen and thus the size of the images.
To zoom all the images currently displayed either:
• use the Zoom control on the main page
• hold the SHIFT key and drag with the left mouse button depressed – up to zoom
out and down to zoom in.
To zoom an individual image to full screen size, right click over the image and select the
Full View option. Left click to return to normal size.
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Coronal Display
Coronal slice display
The options are the same as for the Transverse Display page.
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Sagittal Display
Sagittal slice display
The options are the same as for the Transverse Display page.
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Two Study Mode
Study View 1/2
This option is available if more than one study is loaded. The viewing mode you are in
will determine whether you can choose to display study 1 or study 2 alone, both studies
together or fused studies.
TCS Display
Single study
Two studies
simultaneously
Fused studies
yes
yes
Vertical TCS
Display
yes
no
Non-TCS
Display
yes
no
yes
no
yes
You can select which study to view using the View: control shown below. The 1/2 button
will display both studies simultaneously.
If two studies are being displayed, two independent colour tables are used. As you
triangulate on a study, the corresponding control button is automatically set.
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Study View 1/2 display, with study 1 (CT) in the upper row and study 2 (PET) in the
lower row
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Align
This function allows you to manually register two studies. In the Studies section of the
main window, click on the Align button (indicated in red below) to display the Align
controls:
Click Align to display controls
Align Controls
In order to align the upper and lower studies, the orientation and position of the lower
image can be adjusted using the controls shown.
To align the lower image, drag the slider for the desired axis and release. Alternatively,
the slider can be adjusted by clicking on the arrows to the right of the slider and then
clicking on the Align Volume button (this must be clicked for the alignment to be applied).
Click the Reset button to reset the lower image to its original position when loaded.
The two images can be automatically overlaid, one on top of the other, using the Fusion
control available in the Colour/Threshold Limits section of the main window (see next
page).
Note
If regions have been grown on the lower image, they will be removed when the study is
aligned. A popup window will warn that this will occur.
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Fusion
When viewing two studies together (Study View 1/2), this option allows you to fuse the
images for display. In the Colour/Threshold limits section of the main window, click on
the Fusion button (indicated in red below) to fuse the images.
Fusion Control (indicated in red)
To change the degree of the overlay (the degree of alpha blending), use the slider next
to the Fusion button. When this slider is positioned to the far left, only the first study is
displayed. When it is positioned to the far right, only the second study is displayed.
The colour tables and thresholds or window/levels are separate in fusion mode from
those used in non-fusion mode and must be set and saved as preferences or in a
protocol independently of the main colour tables.
If two MIP movie images are displayed, they are not fused.
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Fused display, with lower study (PET) displayed in colour and overlaid onto the upper
study (CT)
Volume of Interest (VOI) options
The controls for growing a Volume of Interest are found in the VOI section of the main
window.
Creating a VOI
To grow a volume of interest, move the mouse pointer to the center of the region you
wish to draw. Click the VOI button and a box will appear on all three projections. Adjust
the size of the box to encompass the region you wish to grow, by clicking on and
dragging the sides of the box in any of the planes. You can reposition the center of the
box while maintaining its volume simply by clicking on a new desired center. The
maximum pixel and SUV values within the VOI (if applicable) will be updated as you
move the VOI or release the mouse, according to the setting of the VOI Calculation
option in the Tools page. If two studies are selected, VOI data are displayed for both
datasets simultaneously.
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Pixel values for a pixel or VOI
In TCS mode, the program will display the pixel value and the Standard Uptake Value
(SUV)2 value (if applicable) underneath the mouse or in a volume of interest, providing
all the data required to calculate the SUV is available in the data header.
The formula used for calculating SUV 3 is:
The program will report the pixel value and if data is available to calculate it, the socalled SUV4 value under the mouse pointer.
The formula used to calculate SUV is:
 Weight 
SUV = PixelValue
1000
 Dose 
PixelValue
Weight
Dose
Calibrated pixel value in Bq/cc
Patient weight in kg
Injected dose in Bq decay corrected to the time of injection.
1000 is the number of cc/kg for water (an approximate conversion of patient weight to
distribution volume).
The following criteria must be met for the SUV value to be calculated and displayed.
1. Pixel value in Bq/cc5
2. Patient weight in Kg
3. Injection time
4. Scan Start time
5. Injected dose in Bq
6. If injected dose is corrected to scan start
The SUV display can be switched ON and OFF in the Tools page if desired.
Growing a region within a VOI
A region can be grown within the volume of interest, based on an upper limit within the
volume of interest. The grow limit can be set in percentage of maximum value, or in
absolute SUV units, by clicking the Percent and SUV tabs respectively. This setting can
2
SUV Standard Uptake Value
John W. Keys, Jr. Jour Nuc Med. Vol 36, No 10, p 1836-1839
3
Role of Nuclear Medicine in the Evaluation of the Solitary Pulmonary Nodule
Stanley J. Goldsmith and Lale Kostakoglu Seminars in Ultrasound, CT, and MRI,
Volume 21 Number 2, April 2000
SUV: Standard Uptake or Silly Useless Value? John W. Keyes, Jr JNM; Vol 36; No
10, p.1836-1839
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For Gemini PET a special handling is sued, the native data is read from the Dicom
data and proper Bq/cc can be calculated even if the Pixel unit is not Bq/cc in the
header.
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be changed and the region recalculated at any time. Once the limit has been set, the
Grow region option should be clicked and the region will be calculated and the results
displayed for average pixel value, average SUV (if applicable) and volume for the grown
region. The software uses contiguous pixel levels to draw the region, based on the
thresholds set by the user. A sample region and results are shown below. The grown
region can be displayed as solid Colour, as hatched or as an outline, according to the
setting of Contour Format in the Tools page. The grown region is then represented as a
set of contours on the Coronal and Sagittal slices
The SUV display can be toggled off in the Tools page if required. If two studies are
loaded the results for both studies are displayed.
With Volume of Interest OFF (VOI deselected), the SUV and pixel values for the pixel
underneath the mouse are displayed. With Volume of Interest ON (VOI selected) the
maximum pixel value and SUV value within the volume are displayed.
VOI results
Grown region within VOI shown in red, with count and SUV values displayed as
indicated near top left of the main window
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Limitations regarding the use of SUVs
In the paper entitled SUV: Standard Uptake or Silly Useless Value?6 Dr. Keyes
suggests that SUVs are affected (with differences of up to 50%) by several factors,
including:
• Patient size
• Standardized measurement times
• Plasma glucose levels
• Recovery coefficients and partial volume effects
• ROI effects
In addition to these factors, the maximum SUV value of regions of interest may be
reduced, compared to the original acquisition, by registering a PET study to another
study, as voxels will be repositioned during the registration operation. The value may
also be reduced in studies acquired on a combined PET-CT scanner, as the second
study may need to be realigned to the first.
Even if registration has not taken place, the maximum SUV value should be used with
care.
Tools Page
To display the Tools page, click on the button located at the top of the RAPID screen.
The Tools Page has six sub tabs:
At the far bottom of the Tools window is a push button Save Preferences that will save
the current setup as a local preference in
C:\My Documents\Rapid\Preferences\rapidrc.xml.
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SUV: Standard Uptake or Silly Useless Value? John W. Keyes, Jr JNM; Vol 36; No
10, p.1836-1839
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In order for the RAPID program to read the stored local preferences, the setting Read
Local Pref, in the General Tools page, must be ON in the initial preference file. If that
preference is ON, the program will read the locally stored preference file.
Preferences and protocols are not read or saved with Rapid for CD.
General
Local Preferences
If preferences have been stored on the PC by clicking Save Preferences, this will choose
whether they are used or not.
Note
This does not apply to Rapid for CD. The preferences for Rapid for CD can be
configured on a PC running Rapid for PC, saved and the file
C:\My Documents\Rapid\Preferences\rapidrc.xml copied to the Hermes directory
/var/opt/hermes/RAPID4CD/preferences. This file will then be copied onto each Rapid
CD written on that Hermes system
Honour window/level hints
If the studies to be loaded have been saved with the colour table thresholds and/or
window and level settings, and this option is set ON, the studies will be displayed with
the saved values. If the studies have been written to a RAPID CD, these are the values
saved by selecting the Save Window/Level option from the File menu of the Volume
Display program.
For CT studies, the Honour CT window/level hints option must also be set ON if the
saved values are to be honoured.
Honour CT window/level hints
If the studies to be loaded have been copied with the CT window and level settings, and
this option and the Honour window/level hints described above are set ON, the studies
will be displayed with the saved values. If the studies have been written to a RAPID CD,
these are the values saved by selecting the Save Window/Level option from the File
menu of the Volume Display program.
This option allows users to override saved windows and levels and use their own choice
of CT windowing on all studies.
New Patient in New Instance
If it is required to view another study, this selects whether the existing study remains or
is closed before the new one is loaded.
Window Size Option
Set this to the same size as the Display setting in the Windows Control Panel.
Window Background
Select whether the background is black, white or set automatically (recommended).
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SUV Option
Use this option to switch the SUV value display on or off. When the display is switched
off, the maximum and average SUV values for a PET study will not be displayed in the
VOI region of the main window and the SUV values will not be displayed when the
images are triangulated in either of the TCS modes.
Threshold/Colour Options
Use these controls to choose whether to display the lower and upper threshold limits as
percentages, as pixel values for PET studies, or as window-level values for MR and CT
studies. These values are displayed in the Colour/Threshold limits section of the Main
Window.
The CT setting assumes that the image pixel values represent Hounsfield numbers.
The MR setting uses the pixel values in the images.
Which Control at Start
This setting determines which control button is selected when the program is started.
If a CT and PET study pair are loaded, this should be set to #2, as it will almost always
be necessary to change the upper pixel value in the threshold/level setting for the PET
study, whereas the CT window level can be set in a protocol or stored in the
preferences, and may not need to be changed.
VOI Calculation Option
Use this option to choose whether the SUV for a Volume of Interest (VOI) changes as
you move the region, by holding down the mouse button, or whether the number
changes after the region is selected and the mouse button has been released.
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Layout
TCS Layout
Use this control to change the order in which the slices and MIP movie are displayed on
the TCS Display page.
Cross options
There are three options for how the cross appears on the TCS Display images: Full
Cross, Incomplete Cross and Partial Cross. The image can also be displayed without a
cross (Cross Off). These can also be changed by right clicking over any of the TCS
images in the TCS Display.
Full Cross
In full cross mode the lines are visible on the entire image and meet at the center, as
shown below:
Incomplete Cross
In the incomplete cross mode the lines are visible on the entire image except at the
center where they would meet, as shown below:
Partial cross
In partial cross mode, the lines are only visible at the edges of the image frame, as
shown below:
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Cross Off
In this mode, no cross is displayed.
Order of Images
Use this control to change the order in which the program will scroll through slice
images, either manually or as a movie, for each orientation.
Contour Format
The grown region contour can be set to filled-in, semi-filled or non-filled.
Movie
Movie layout
Choose if MIP movie is displayed on the far left or far right of the window in the TCS
Display page.
Colour Selection Option
Select whether the MIP movies have separate colour tables.
On/Off Options
Show or hide the MIP movie
Generation options
Choose whether a MIP movie shall be created from the volume data when the program
starts. If a CT or MR is loaded as study 1 and a SPECT or PET study as study 2, it is
recommended to select the Only Create Second Movie option, which will only create a
MIP movie for the second study if two studies are loaded
Print
Set the print margins and optionally the Windows printer name.
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Protocols
Here protocols can be saved, loaded or deleted. A protocol is loaded after the program
has started, either from this page or from the menu on the main RAPID page.
Changing some options, such as movie generation mode, and window sizes, will have
no effect on the program until it is restarted. The protocols are stored as XML files in
C:\My Documents\Rapid\Protocols.
This does not apply to Rapid for CD.
.
CT Window/Level
Up to 5 window names can be configured here, each with its own window/level setting.
Note
Nuclear Diagnostics has added some private keys to the Interfile header to handle PET
data.
NUD/uid code
NUD/Patient Weight [kg]
NUD/PET SUV Factor
NUD/activity
NUD/activity start time
NUD/radiopharmaceutical
NUD/isotope half life [hours]
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A unique UID like in Dicom
Patient weight in kilograms.
Factor to convert pixel value to SUV
Dose injects in Bq
Dose Start Time
Radio pharmaceutical
Isotope half-life in hours.
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NUD/Pixel Value Units
NUD/rescale intercept
NUD/rescale slope
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Pixel value units (Bq/cc)
Pixel offset to add to Image
Factor to multiply pixel values to get
TRUE pixel value
True Pixel Value =
StoredPixel*slope + intercept.
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