ACQUISITION

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

PLANAR:

• Whole-body Sweep: ABDY - Scan of 8 - 10 cm/minute (10 Minute / Meter) starting at the head to the level of the mid-thigh.

OR

• ASTA- Spot Views: Anterior and Posterior Views for 10 minutes/image of the pelvis, abdomen and chest.
• Matrix: 256
• Word mode

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

• ATOM-
• Single-head SPECT: Use a 64 matrix with 64 total views for 30-40 seconds/view.
• Dual-head SPECT: Use a 128 matrix with 128 total views for 30-40 seconds/view (The 64 X 64 matrix is adequate, but the 128 X 128 should produce better images).
• 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; perform approximately 18-24 hours post injection ) Position the camera to include the entire chest and the axilla. Use a 64 matrix with 64 total views and set the acquisition for 60-70 seconds/step.

PROCESSING

PLANAR DISPLAY:

• DISP
• 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.

CINE RAW DATA DISPLAY:

• DISP-
• Check SPECT for motion and vary intensity to look for any suspicious uptake.

SPECT PROCESSING

USE: RECON

• Set the transaxial slice to 2
• Reconstruction: 2
• Choose Butterworth as the prefilter
• Cutoff: .25-.45 (Use a cutoff which displays sharp edges of the vessels.)
• Set the power to 10 (Use a lower power if the study is count deficient.)
• Use a RAMP filter for the backprojection filter.
• Define the limits to include the entire field of view.

**ATTENUATION CORRECTION COMMAND = ADAT:
(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.

Use Image Triangulation to Evaluate the study.
TRIANGULATION COMMAND = TRIF

• By viewing the other two corresponding planes, suspicious structures can be triangulated.
• Repeat this method for each plane.

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

SPECT DISPLAY

SPECT DISPLAY COMMAND = DISP

• Display a maximum of 16 images.

HELPFUL TIPS:

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

DISCLAIMER:

This procedure was not developed by, or is not meant as an endorsement by GE 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.