Siemens Camera Protocol

CEA-Scan ACQUISITION AND PROCESSING
FOR THE SIEMENS SYSTEM

ACQUISITION

ENERGY SETTING: Tc99m - 140 Kev with a 20% Window.

PLANARS:

Whole-body Sweep: Scan speed of 8 - 10 cm/minute starting at the head to the level of the mid-thigh.
Note: ECam - Does not go below 10 cm / Min.

Use: 256x256x16 matrix
Spot Views: Anterior and Posterior Views for 10 minutes/image of the pelvis, abdomen and the chest.

SPECTs: (Always acquire the Pelvic SPECT before the Abdominal SPECT.)

The 64 X 64 matrix is adequate, but the 128 X 128 should produce better images.

Multi-head SPECT: Use a 128 matrix with 3 degree steps for 30-40 seconds/step.
Single-head SPECT: Use a 64 matrix with 6 degree steps for 30-40 seconds/step.
Pelvic SPECT: Position the camera to include the groin to above the bifurcation.
Abdominal SPECT: Position the camera to include the entire liver allowing for some overlap from the Pelvic SPECT.
Chest SPECT: (Acquire the chest SPECT ONLY if there is a clinical indication; image at approximately 18-24 hours post injection.) Position the camera to include the entire chest and the axilla. Use a 64 matrix with 6 degree steps and set the acquisition for 60-70 seconds / step.

PROCESSING

PLANAR DISPLAY:

CHOOSE: D/A
Use Example Display or comparable display protocol
Select Planar Images
Check each image varying the intensity to look for any suspicious areas of uptake.
Use a linear gray scale taking care to not remove any background.
Film the images at two intensities: one lighter and the other dark enough to display the blood vessels intensely.

SPECT PROCESSING

CHOOSE: PROCESS PROTOCOL

Select: SPECT - Example liver
Select: PROJECTION FILE
3 VIEW DISPLAY: Check the CINE for motion
Use the cursor to select TRIAL MODE RECONSTRUCTION at the bottom left of the display.
Use the cursor to move the reference line to a region which best determines proper filtering. For example, try a level through the iliacs for the Pelvic SPECT and a level through the liver for the Abdominal SPECT
Choose: BUTTERWORTH for the RECON filter
Order: 6-10 (Use a lower order if the study is count deficient.)
Cutoff: .25-.45 (Use a cutoff which displays sharp edges of the vessels.)
When the desired filtering is determined return to the 3 VIEW DISPLAY.
Click on PARAMETERS
If all of the reconstructed files are to be saved, click on: TRANSVERSE, SAGITTAL, and CORONAL.
Click on VOLUME RENDERED DATA if the file is to be saved.
Click on File - Save SPECT Paremeter.
Click on DISPLAY to return to the 3 VIEW DISPLAY.
Use the cursor to move the reference lines to include the entire field of view.
Click on RECONSTRUCT.
Click on - File - Save SPECT Data.

Reviewing the SPECT as a 3D Volume is often helpful.

Click on VOLUME RENDERING to create the 3D Volume.
To save the reconstructed files, click on FILE and select SAVE SPECT DATA.
The Volume Rendered Data can be reviewed on the CINE display in the 3 VIEW DISPLAY.

**ATTENUATION CORRECTION: (Use only for the SPECT of the liver, if necessary.)
Occasionally the liver will display a dark rim particularly on the lateral edge of the right lobe. If there is a question of a lesion at the edge of the liver, Attention Correction may help differentiate between a reconstruction artifact and disease. Process the SPECT of the liver with and without attenuation correction and compare the images.

SELECT: PROCESS PROTOCOL

Select: SPECT
Click on PARAMETERS
Select: ATTENUATION CORRECTION
Click on ATTENUATION CORRECTION
Proceed with the SPECT RECONSTRUCTION

SPECT DISPLAY

Use the cursor to select MULTIVIEW at the bottom of the display of the 3 VIEW DISPLAY.
Select: SINGLE DISPLAY (ie. Example Brain)
Click on DISPLAY / No Save Mode.
By moving the cursor to the center image of each line, cross-hairs will appear.
Start with one plane, the transverse for example, and slowly move through the images from top to bottom.
When a suspicious structure appears, move the cross-hairs to the suspicious area and the corresponding other two planes will appear.
Repeat this method using each of the images in the center of each line to triangulate suspicious structures.

Remember to vary the intensity to bring out any subtle structures.

To film the entire study:

SELECT: MULTIVIEW

Use: SINGLE SPLASH (ie: Example Brain).
Film: Transverse, Sagittal and the Coronal images with 2 pixel thick slices.

HELPFUL TIPS:

Do not use any Zoom during the acquisition.
Display a maximum of 16 images for filming.
Read the study on the computer screen, document the abnormalities on film.
Some images may require filming with two or more intensities.
The use of 3D Volume Display may be helpful.

DISCLAIMER:

This procedure was not developed by, or is not meant as an endorsement by Siemens of CEA-Scan. These suggested parameters are based on the experience of various users with this type of equipment and are not a substitute for the physician's or technologist's professional experience or knowledge. Users are ultimately responsible for determining if this procedure is usable with their equipment and standard practices. It is assumed that Quality Control of the imaging equipment is performed according to the manufacturer's recommendations. Please refer to the full product prescribing information and consult your equipment manufacturer's updated user's manual prior to the first use of CEA-Scan.

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