ACQUISITION

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

PLANARS:

• Whole-body Sweep: Scan speed of 7.5 or 10 cm/minute starting at the head to the level of the mid-thigh.

OR

• Use: 256 x 256 Matrix
• Static Acquisition: Anterior and Posterior views for 10 minutes / image of the pelvis, abdomen and chest.

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

CAMERAS: GCA-602, GCA-901, GCA-7200, GCA-7100, GCA-9300, ECAM.

• Single-head camera:

• Use a 64 matrix with 6 degree steps for 30-40 seconds/step.

• Dual-head camera:

• Use a 128 matrix with 3 degree steps for 30-40 seconds/step (The 64 X 64 matrix is adequate, but the 128 X 128 should produce          better images).
• Ellipse: YES for elliptical, or

• RoboContour: ON for GCA-7100 / 7200.
• Use RoboContour to control ellipse for GCA-7100/7200.

• Ellipse Radius: Set four (4) ellipse points for GCA-602 / 901 / 9300.

• 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 a chest SPECT ONLY if there is 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 6 degree steps for 60-70 seconds/step.

IMAGE DISPLAY

PLANAR DISPLAY:

• Select: FORMATTED DISPLAY
• Select; STATIC or WHOLE BODY - TEMPLATE.
• Check each image varying the UPPER LEVEL to look for any suspicious areas of uptake.
• Use a LINEAR GRAY SCALE taking care to not remove any background with the LOWER LEVEL control.
• Film the images at two intensities: one lighter and the other dark enough to display the blood vessels intensely.

CINE DISPLAY:

• Check each SPECT for motion and vary the intensity to look for any suspicious areas of uptake.

SPECT PROCESSING

SELECT: SPECT

• Use: Recon - > Sagittal - Coronal
• Click on: OBJECTS
• Select: LOAD FILE
• Thickness: 2
• Set cursors to include the entire field of view
• Click on: OPTIONS
• Pre-filter:
• 9BUTTERWORTH for 64 X 64 matrix, or
• F_BUTTERWORTH for 128 X 128 matrix.
• Select: FILTER PREVIEW to try various filter levels.
• Order: 8 (Toshiba only has an Order of 8.)
• Cutoff: (Use a cutoff which displays sharp edges of the vessels.)
• Use .25 to .45 if study was acquired on a 64 X 64 matrix, or
• Use .10 to .25 if study was acquired on a 128 X 128 matrix.
• Reconstruction filter: RAMP
• Click on: APPLY

**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: SPECT

• Use: RECON - > Sagittal - Coronal
• Click on: ATTENUATION
• Use: CYLINDRICAL CHANG
• Select a value for Tc99m from .12 to 15 1/cm
• Continue SPECT PROCESSING

SPECT DISPLAY

Reviewing the SPECT as a 3D Volume is often helpful.
5500 Computers:

• Use: MAX INTENSITY PROJECTION

550 Computers:

• Use: GPL Program for 3-D
• To film the entire study:

SELECT: DISPLAY

• Use: SPECT DISPLAY
• Display a maximum of 16 images.
• Use a LINEAR GRAY SCALE adjusting only the UPPER LEVEL to change the intensity.

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: