GE CT-9800

GE MEDICAL SYSTEMS CT 9800 QUICK SYSTEM
Rev. 6 Direction 18000
6-11-3
3. Mount the patient headholder to the end of the cradle.
4. Turn on the alignment lights.
5. Advance the table into the gantry until the internal alignment light cuts the headholder at the point where you
want to scan (arbitrary).
6. Perform an axial scan of the headholder using the following technique:
Azimuth : 0°
Small Cal
10 mm. aperture
120 kV
40 mA
Gantry Tilt:0°
7. Enter the Display Function and display the resultant image of the headholder (see Ill. 6-11-2).
8. Using the MEASR DISTN (Measure Distance) Function Key and the display grid, measure the distance from
the centerline to each side of the headholder. The difference from centerline to right side and from
centerline to left side shall be less than 0.3 cm.
NOTE: You can measure from the center of the display to the inside or the outside of the
headholder just as long as you are consistent for both sides of the headholder. For
example, in Ill. 6-11-3, the measurement was made from the centerline to the outside
of the headholder. DIST #1 and #2 were both the same (i.e., 10.01 cm.). Therefore,
the difference between DIST. #1 and DIST #2 is zero.
9. If the headholder is off - centered by more than 0.3 cm., then move the table the required amount to center
the headholder in the scan plane. You will have to rescan the headholder to verify proper centering
NOTE: Once you have moved the table until the headholder is centered,
recheck table perpendicularity to scan plane per section 11-1.
10. Tighten down the table base mounting bolts to 20 ft. - lbs.