Dosing Iodinated Contrast Media According to Lean vs. Total Body Weight

Study Overview
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Brief Summary
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The purpose of this study is to evaluate the effect of dosing iodinated contrast media according to a patient's total body weight vs. lean body weight. Participants will be randomized into 2 groups based on contrast dosing technique, and solid organ enhancement at uniphasic abdominal CT will be measured.

Official Title
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Dosing Iodinated Contrast Media According to Lean vs. Total Body Weight at Abdominal CT: a North American Randomized Controlled Trial

Conditions
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Contrast Media Dosing

Intervention / Treatment
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* Drug: Iohexol


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: outpatients only patients scanned on modern Siemens scanners at our institution Exclusion Criteria: self-reported history of chronic kidney, heart or liver disease allergy to iodinated contrast acute illness outside maximum threshold limit for weight-based contrast dosing pregnancy image degradation

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Diagnostic
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Total Body Weight<br> | Drug: Iohexol<br>* Iodinated contrast media<br>|
| Active Comparator: Lean Body Weight<br> | Drug: Iohexol<br>* Iodinated contrast media<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Mean hepatic enhancement (MHE): difference in liver attenuation on computed tomography images acquired before and after administration of contrast (in portal venous phase), as measured in Hounsfield units (HU) | Images of the liver will be obtained before and after administration of iodinated contrast media. Regions of interest will be drawn on these pre- and post- contrast computed tomography (CT) images of the liver. The average attenuation before and after contrast administration will be calculated. The mean hepatic enhancement (MHE) will be calculated as the average attenuation post-contrast minus the average attenuation pre-contrast. This will provide a measure of liver enhancement. | 1 hour | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Standard deviation in mean hepatic enhancement (sigma MHE): standard deviation in the difference in liver attenuation on CT acquired before and after administration of contrast (in portal venous phase), as measured in Hounsfield units (HU) | Images of the liver will be obtained before and after administration of iodinated contrast media. Regions of interest will be drawn on these pre- and post- contrast computed tomography images of the liver. The average attenuation before and after contrast administration will be calculated. The mean hepatic enhancement (MHE) will be calculated as the average attenuation post-contrast minus the average attenuation pre-contrast. The standard deviation in MHE will provide a measure of inter-patient variability. | 1 hour |