Pulmonary Embolism
Conditions
Keywords
Pulmonary Embolism, Spectral Detector CT, Contrast medium
Brief summary
The purpose of this study is to assess the effect of three different strategies to inject at reduced volume of contrast medium in Computed Tomography Pulmonary Angiography (CTPA). 330 patients referred for CTPA are randomized to receive either a low-concentration, a low-volume or a saline-diluted injection. Effects on the level and homogeneity of contrast enhancement are measured and compared between groups.
Detailed description
Spectral detector CT facilitates large reductions in contrast medium in vascular CT examinations. To our knowledge, no studies have so far compared different strategies to inject this reduced contrast dose. The purpose of this study is to assess the effect of three different strategies to inject at reduced volume of contrast medium in Computed Tomography Pulmonary Angiography (CTPA). 330 patients referred for clinically indicated CTPA are randomized to receive either a low-concentration, a low-volume or a saline-diluted injection. All patients receive the same amount of iodine (140 mg/kg). Effects on the level and homogeneity of contrast enhancement, image noise, contrast-to-noise-ratio and signal-to-noise-ratio are measured in the CT images and the results are compared between groups.
Interventions
DIAGNOSTIC_TESTLow iodine Spectral Detector CT Pulmonary Angiography
Low iodine Spectral Detector CT Pulmonary Angiography
Sponsors
University Hospital, Akershus
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
DIAGNOSTIC
Masking
TRIPLE (Subject, Investigator, Outcomes Assessor)
Masking description
Acquired CT images are identical for all participants. The study arm is unknown to all, except the radiographers (radiology technicians) performing the examination.
Intervention model description
Patients are randomly assigned to one of three injection methods: low concentration, low-volume and saline-dilution.
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Inpatients and outpatients with kidney function (eGFR) allowing for safe administration of contrast dose (as calculated with the OmniVis calculator). * Patients with clinical suspicion of disease of PE * Referral to CTPA diagnosis, treatment planning or follow-up. * Peripheral venous catheter (PVC) =/\< 18 G
Exclusion criteria
* Contraindication to iodinated contrast medium * Age \< 18 years * Lack of informed consent * Pregnancy
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Contrast enhancement (Vascular attenuation) | Measured on the CT images from the examination performed at enrollment | Contrast enhancement measured as attenuation in the pulmonary artery Branches on the acquired CTPA examination |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Homogeneity of contrast enhancement (image noise) | Measured on the CT images from the examination performed at enrollment | Homogeneity of contrast enhancement is measured as the standard deviation of attenuation in the pulmonary artery branches (equals image noise). |
| Contrast to noise ratio (CNR) | Measured on the CT images from the examination performed at enrollment | CNR is measured as (Vascular attenuation - Muscular attenuation) / Image noise |
| Signal to noise ratio (SNR) | Measured on the CT images from the examination performed at enrollment | SNR is measured as Vascular attenuation / Image noise |
Countries
Norway
Outcome results
None listed