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Strategies to Reduce Contrast Medium in Spectral CT Pulmonary Angiography

Not Applicable
Completed
Conditions
Pulmonary Embolism
Interventions
Diagnostic Test: Low iodine Spectral Detector CT Pulmonary Angiography
Registration Number
NCT05592444
Lead Sponsor
University Hospital, Akershus
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.

Recruitment & Eligibility

Status
COMPLETED
Sex
All
Target Recruitment
330
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

Study & Design

Study Type
INTERVENTIONAL
Study Design
PARALLEL
Arm && Interventions
GroupInterventionDescription
Low concentrationLow iodine Spectral Detector CT Pulmonary AngiographyPatients receive a contrast medium with an iodine concentration of 140 mg/ml. The volume is 1 ml/kg which result in a dose of 140 mg/kg. Maximal dose of contrast medium is 90 ml i.e. 12.6 g of iodine.
Saline DilutionLow iodine Spectral Detector CT Pulmonary AngiographyPatients receive a contrast medium with an iodine concentration of 350 mg/ml. The contrast medium is diluted 1:1 with saline. The injected volume is 0.8 ml/kg which result in a dose of 140 mg/kg. Maximal dose of contrast medium is 72 ml i.e. 12.6 g of iodine.
Low volumeLow iodine Spectral Detector CT Pulmonary AngiographyPatients receive a contrast medium with an iodine concentration 350 of mg/ml. The volume is 0.4 ml/kg which result in a dose of 140 mg/kg. Maximal dose of contrast medium is 36 ml i.e. 12.6 g of iodine.
Primary Outcome Measures
NameTimeMethod
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 Outcome Measures
NameTimeMethod
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

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).

Signal to noise ratio (SNR)Measured on the CT images from the examination performed at enrollment

SNR is measured as Vascular attenuation / Image noise

Trial Locations

Locations (1)

Akershus University Hospital

🇳🇴

Lørenskog, Viken, Norway

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