Trial Outcomes & Findings for Breast Displacement and CT Radiation Dose (NCT NCT01261559)
NCT ID: NCT01261559
Last Updated: 2018-07-06
Results Overview
Skin entrance radiation doses will be measured with Thermoluminescent dosimeters (TLDs) affixed to the subject's chest and breast during CT of the abdomen. TLD #1 is at the inframammary fold, serving as internal control for each subject. Three additional TLDs (#2-4) are affixed to the subject's breast at 3 pre-ascribed locations. The same is done for the right and left breasts (8 TLDs total). TLDs will then be submitted to Landaeur for measurement.
COMPLETED
NA
72 participants
from time potential subject approached about possible enrollment to time device and TLDs were removed, on average 1 hour
2018-07-06
Participant Flow
Recruitment: December 2010 to February 2012, at Harborview Medical Center (inpatient wards, outpatient clinics, and emergency departments)
All women who were approached for the study were screened for exclusion criteria prior to enrollment. 110 eligible patients were approached, and 37 declined participation or met exclusion criteria. 1 subject was scanned but TLD readings were clearly erroneous and were therefore excluded. 72 subjects were ultimately included in analyses.
Participant milestones
| Measure |
Standard CT
Women assigned to undergo CT using the standard dose reduction methods (including bismuth shielding and tube current modulation) but without the Chrysalis device.
|
Chrysalis CT
Women assigned to undergo CT using the standard dose reduction methods (including bismuth shielding and tube current modulation) plus application of the Chrysalis device for breast displacement.
|
|---|---|---|
|
Overall Study
STARTED
|
36
|
36
|
|
Overall Study
COMPLETED
|
36
|
36
|
|
Overall Study
NOT COMPLETED
|
0
|
0
|
Reasons for withdrawal
Withdrawal data not reported
Baseline Characteristics
Breast Displacement and CT Radiation Dose
Baseline characteristics by cohort
| Measure |
Standard CT
n=36 Participants
Women assigned to undergo CT using the standard dose reduction methods (including bismuth shielding and tube current modulation) but without the Chrysalis device.
|
Chrysalis CT
n=36 Participants
Women assigned to undergo CT using the standard dose reduction methods (including bismuth shielding and tube current modulation) plus application of the Chrysalis device for breast displacement.
|
Total
n=72 Participants
Total of all reporting groups
|
|---|---|---|---|
|
Age, Categorical
<=18 years
|
0 Participants
n=93 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=27 Participants
|
|
Age, Categorical
Between 18 and 65 years
|
36 Participants
n=93 Participants
|
36 Participants
n=4 Participants
|
72 Participants
n=27 Participants
|
|
Age, Categorical
>=65 years
|
0 Participants
n=93 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=27 Participants
|
|
Age, Continuous
|
40.2 years
STANDARD_DEVIATION 12.9 • n=93 Participants
|
40.3 years
STANDARD_DEVIATION 12.8 • n=4 Participants
|
40.3 years
STANDARD_DEVIATION 12.8 • n=27 Participants
|
|
Sex: Female, Male
Female
|
36 Participants
n=93 Participants
|
36 Participants
n=4 Participants
|
72 Participants
n=27 Participants
|
|
Sex: Female, Male
Male
|
0 Participants
n=93 Participants
|
0 Participants
n=4 Participants
|
0 Participants
n=27 Participants
|
|
Region of Enrollment
United States
|
36 participants
n=93 Participants
|
36 participants
n=4 Participants
|
72 participants
n=27 Participants
|
PRIMARY outcome
Timeframe: from time potential subject approached about possible enrollment to time device and TLDs were removed, on average 1 hourSkin entrance radiation doses will be measured with Thermoluminescent dosimeters (TLDs) affixed to the subject's chest and breast during CT of the abdomen. TLD #1 is at the inframammary fold, serving as internal control for each subject. Three additional TLDs (#2-4) are affixed to the subject's breast at 3 pre-ascribed locations. The same is done for the right and left breasts (8 TLDs total). TLDs will then be submitted to Landaeur for measurement.
Outcome measures
| Measure |
Standard CT
n=36 Participants
Women assigned to undergo CT using the standard dose reduction methods (including bismuth shielding and tube current modulation) but without the Chrysalis device.
|
Chrysalis CT
n=36 Participants
Women assigned to undergo CT using the standard dose reduction methods (including bismuth shielding and tube current modulation) plus application of the Chrysalis device for breast displacement.
|
|---|---|---|
|
Skin Entrance Radiation Dose During Computed Tomography (CT)
Mean entrance skin dose at inframammary fold
|
1775 mrad
Standard Deviation 1634
|
1325 mrad
Standard Deviation 1158
|
|
Skin Entrance Radiation Dose During Computed Tomography (CT)
Mean breast entrance skin dose (average TLD2-4)
|
625 mrad
Standard Deviation 677
|
259 mrad
Standard Deviation 334
|
PRIMARY outcome
Timeframe: from time potential subject approached about possible enrollment to time device and TLDs were removed, on average 1 hourRelative skin entrance dose at the breast (group mean of patient's average skin entrance dose at TLDs 2-4) divided by skin entrance dose at the inframammary TLD (TLD 1) in %. For each patient, doses at TLDs 2-4 were averaged, and then the group mean of this was divided by the group mean at the inframammary TLD, then multiplied by 100 to get % dose. A relative dose of 20% means that the skin entrance dose at the breast was 20% of the skin entrance dose at the inframammary fold.
Outcome measures
| Measure |
Standard CT
n=36 Participants
Women assigned to undergo CT using the standard dose reduction methods (including bismuth shielding and tube current modulation) but without the Chrysalis device.
|
Chrysalis CT
n=36 Participants
Women assigned to undergo CT using the standard dose reduction methods (including bismuth shielding and tube current modulation) plus application of the Chrysalis device for breast displacement.
|
|---|---|---|
|
Relative Skin Entrance Radiation Dose in % During Computed Tomography (CT)
|
37 percentage of dose
Standard Deviation 30
|
36 percentage of dose
Standard Deviation 11
|
SECONDARY outcome
Timeframe: two monthsPopulation: In some cases, a reliable measurement of noise could not be measured on the location. For example, if the breast was not included on the CT, breast noise could not be measured (12 controls and 21 Chrysalis). Too little retroperitoneal or subcutaneous fat was present to draw the relevant ROI in 1 control and 1 Chrysalis subject, respectively.
To evaluate image noise, mean of the Standard deviation (SD) of the pixel values, measured in Hounsfield units (HU), will be measured in Picture Archiving and Communication System (PACS) using a region of interest (ROI) measuring 90-110 mm\^2 in size drawn over each of these body regions: hepatic dome, spleen, renal cortex, retroperitoneal fat, subcutaneous fat, paraspinal muscles, and if present, breast tissue, avoiding vascular structures in each case. SD for ROI measuring 90-110 mm\^2 in size will also be drawn over the aorta and inferior vena cava (IVC), remote from contrast mixing artifact, and over medullary bone of the spine. HU is the linear scale by which digital image data are displayed in PACS and reflect relative attenuation compared to distilled water at a standard temperature and pressure (STP) (defined as 0 HU) and of pure air at STP (defined as -1000HU). Within a drawn ROI, the PACS will give the mean attenuation (in HU) and the standard deviation of HU (reflecting
Outcome measures
| Measure |
Standard CT
n=36 Participants
Women assigned to undergo CT using the standard dose reduction methods (including bismuth shielding and tube current modulation) but without the Chrysalis device.
|
Chrysalis CT
n=36 Participants
Women assigned to undergo CT using the standard dose reduction methods (including bismuth shielding and tube current modulation) plus application of the Chrysalis device for breast displacement.
|
|---|---|---|
|
CT Image Noise
Medullary Bone of Spine
|
31.2 Hounsfield units
Standard Deviation 7.4
|
34.8 Hounsfield units
Standard Deviation 18.2
|
|
CT Image Noise
Paraspinal muscle
|
19.8 Hounsfield units
Standard Deviation 7.7
|
17.9 Hounsfield units
Standard Deviation 5.6
|
|
CT Image Noise
Liver dome
|
17.1 Hounsfield units
Standard Deviation 5.9
|
16.4 Hounsfield units
Standard Deviation 6.9
|
|
CT Image Noise
Spleen
|
23.2 Hounsfield units
Standard Deviation 8.1
|
21.1 Hounsfield units
Standard Deviation 7.3
|
|
CT Image Noise
Kidney
|
26.8 Hounsfield units
Standard Deviation 8.0
|
24.5 Hounsfield units
Standard Deviation 6.8
|
|
CT Image Noise
Aorta (without mixing artifact)
|
19.7 Hounsfield units
Standard Deviation 5.0
|
21.1 Hounsfield units
Standard Deviation 7.26
|
|
CT Image Noise
IVC (without mixing artifact)
|
21.1 Hounsfield units
Standard Deviation 5.1
|
22.9 Hounsfield units
Standard Deviation 5.7
|
|
CT Image Noise
Retroperitoneal fat
|
24.4 Hounsfield units
Standard Deviation 7.9
|
23.4 Hounsfield units
Standard Deviation 7.0
|
|
CT Image Noise
Subcutaneous fat
|
13.3 Hounsfield units
Standard Deviation 4.0
|
12.9 Hounsfield units
Standard Deviation 3.5
|
|
CT Image Noise
Breast (if imaged)
|
26.0 Hounsfield units
Standard Deviation 9.9
|
26.1 Hounsfield units
Standard Deviation 11.1
|
SECONDARY outcome
Timeframe: two monthsCT images acquired will be reviewed for the presence of artifacts that might be attributed to the displacement device or to the presence of the breast tissue. To evaluate for artifacts, the exam will be qualitatively reviewed by a board certified radiologist for imaging artifacts, such as streak artifact. It will be noted on a per participant basis whether any imaging artifacts are identified.
Outcome measures
| Measure |
Standard CT
n=36 Participants
Women assigned to undergo CT using the standard dose reduction methods (including bismuth shielding and tube current modulation) but without the Chrysalis device.
|
Chrysalis CT
n=36 Participants
Women assigned to undergo CT using the standard dose reduction methods (including bismuth shielding and tube current modulation) plus application of the Chrysalis device for breast displacement.
|
|---|---|---|
|
Number of Participants With Presence of Artifacts Based on CT Image Quality
|
0 Participants
|
0 Participants
|
Adverse Events
Standard CT
Chrysalis CT
Serious adverse events
Adverse event data not reported
Other adverse events
Adverse event data not reported
Additional Information
Results disclosure agreements
- Principal investigator is a sponsor employee
- Publication restrictions are in place