Brilliance 64 HCOR problem

Hi there,
Have you done air before? Is there bad detectors found on system? Have you aligned proper phantoms? Does it says while common hcor or per slice? Are images clear from any objects? Check for correct type of phantom in preferences. It should be one part phantom. Email me with the images to ct.spare.part@gmail.com I'll try to help.
Regards
Artem.

During HCOR calibration the system automatically pulls ROI's from different materials within the phantom. If any of the hounsfield numbers are far enough outside of the expected values for that material it will not continue and apply the correction offsets. This can be caused by several issues including bad air cals, reference detector problem, temperature environment, etc..... However if your numbers are ok during normal scans the most probable cause is phantom centering. Since the regions are pulled by software it is critical to have near perfect centering in all 3 axis. If it is slanted then the slice it is using for data could be going through more attenuation for that substance and hence your hounsfield numbers are off.

Thank you guys for the prompt answer but I have the solution. I post it here for the sake of completeness.

HCOR Problem description and solution

Description

In the ……. was not possible to run the HCOR procedure. The procedure always stopped at the 80KV 340mA phase
tellint to the operator that it was not possible to update the hcor parameters due to a too far distance between the adjustment gap of 2% and the actual 13%. The image shown at this step reported wrong CT numbers as you can see
in the image file of this folder. See the text file of this folder for the HCOR output file.

Solution

To solve the problem it is necessary to update the air tables in the CIRS issuing the command SetTablesUts.bat under C:/usr/diamond.root/bin in a DOS window of the host.

HCOR Output:

May-15-15 15:29:04.234 Scan: 0.75sec, 16x2.5mm, STD, 120kV, 267mA, DFSX, WLarge, filter TiFull
May-15-15 15:29:32.421 Message: Auto moving the patient table to Y-position 121 mm.
May-15-15 15:29:44.390 Scan: 0.75sec, 16x2.5mm, STD, 120kV, 267mA, DFSX, WLarge, filter TiFull
May-15-15 15:29:54.156 Scan: 0.75sec, 32x1.25mm, STD, 80kV, 267mA, DFSX, WLarge, filter TiFull
May-15-15 15:30:05.328 Results: Meas.CT = 3.3, std = 19.5591, Curr.F = 0.9429. New F = 0.9398 (updated) Diff. from default = 0.5%
May-15-15 15:30:05.328 Results: Measured CT for central slices (15-18): 3.30 3.49 3.35 3.32 3.03
May-15-15 15:30:05.828 Scan: 0.75sec, 32x1.25mm, STD, 120kV, 267mA, DFSX, WLarge, filter TiFull
May-15-15 15:30:17.984 Results: Meas.CT = 2.4, std = 8.6660, Curr.F = 1.0643. New F = 1.0617 (updated) Diff. from default = 0.4%
May-15-15 15:30:17.984 Results: Measured CT for central slices (15-18): 2.44 2.57 2.46 2.42 2.30
May-15-15 15:30:18.468 Scan: 0.75sec, 32x1.25mm, STD, 140kV, 267mA, DFSX, WLarge, filter TiFull
May-15-15 15:30:30.515 Results: Meas.CT = 2.4, std = 7.1567, Curr.F = 1.1002. New F = 1.0976 (updated) Diff. from default = 0.4%
May-15-15 15:30:30.531 Results: Measured CT for central slices (15-18): 2.37 2.60 2.41 2.34 2.12
May-15-15 15:30:31.000 Scan: 0.75sec, 32x1.25mm, STD, 80kV, 340mA, DFSX, WLarge, filter TiFull
May-15-15 15:30:43.921 Results: Meas.CT = 162.1, std = 54.3647, Curr.F = 1.0075. New F = 0.8670 (NOT UPDATED) Diff. from default = 13.7%
May-15-15 15:30:43.921 Results: Measured CT for central slices (15-18): 162.10 163.04 162.72 164.24 158.39
May-15-15 15:30:43.921 Results: New F = 0.8670, differs from Default F of 1.0050 by 13.73%, more than the tolerance of 2.00%.