Ultra Low Iodine Loaded Spectral CT Angiography (CTA)

Peripheral Arterial Disease Clinical Trial

Official title:

Ultra Low Iodine Loaded Spectral CT Angiography (CTA) of the Aorta and Lower Limb: A Randomized Controlled Trial

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT05488899
• Other study ID #: 2018_070
• Status: Completed
• Phase: N/A
• Start date: January 28, 2019
• Est. completion date: October 16, 2020

Study information

• Verified date: August 2022
• Source: University Hospital, Akershus
• Contact: n/a
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The objectives of this study are:

Evaluation of ultra-low iodine load CTA protocols of the aorta and lower extremities.

To investigate whether dual-layer in combination with with virtual monoenergetic imaging (VMI) allows for reduction of contrast medium (CM) in CTA of the aorta and lower limbs i with sustained objective and subjective image quality parameters.

Description:

CT angiography (CTA) of the aorta and the lower limb is one of the most important tools for diagnostic, evaluation of the severity of the peripheral arterial disease, decision making, treatment planning and follow-up; but usually requires the use of iodine contrast medium.

Due to the high prevalence of renal impairment (eGFR < 90 ml/min/1.73m) in the elderly hospitalized population (more than 90% among inpatients aged over 60 years) contrast-medium-induced nephropathy is a major concern in this population.

The recently introduced spectral CT technique utilizes x-rays covering a spectrum of energy-levels as opposed to conventional CT in which x-rays are set to one specific energy level.

This technology offers many possibilities, such as "boosting" the x-ray contrast effect of iodine. This improves the vascular enhancement of the contrast medium using low-energy, virtual monoenergetic imaging (VNI).

The objectives of this study are:

Evaluation of ultra-low iodine load CTA protocols of the aorta and lower extremities.

To investigate whether dual-layer in combination with with virtual monoenergetic imaging (VMI) allows for reduction of contrast medium (CM) in CTA of the aorta and lower limbs i with sustained objective and subjective image quality parameters.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 216
• Est. completion date: October 16, 2020
• Est. primary completion date: October 16, 2020
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

• Inpatients and outpatients with kidney function (eGFR) allowing for safe administration of standard contrast dose (as calculated with the OmniVis calculator).

• Patients with clinical suspicion of disease of the aorta and/or arteries in the lower limb.

• Referral to CTA diagnosis, treatment planning or follow-up.

Exclusion Criteria:

• Iodine contrast medium allergy

• Age < 18 years

• Lack of informed consent

• Critical ischemia of the lower extremities

Related Conditions & MeSH terms

• Peripheral Arterial Disease
• Peripheral Vascular Diseases
• Renal Insufficiency

Intervention

Diagnostic Test:
• Half iodine Spectral CT
Patients receive half dosage of iodine contrast agent, and Spectral CT acquisition with Virtual Monoenergetic Images at 40 and 50 keV.
• Standard iodine conventional CT
Patients receive standard dosage of iodine contrast agent, and conventional 120 kv Polychromatic CT acquisition.

Locations

Country	Name	City	State
Norway	Akershus University Hospital	Lørenskog	Viken

Sponsors (2)

Lead Sponsor	Collaborator
University Hospital, Akershus	Oslo Metropolitan University

Country where clinical trial is conducted

Norway, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Other	Image noise	Image noise was defined as the standard deviation of arterial attenuation measurements (see outcome 1) measured in HU digitally by placing a ROI on the CT-images in the aorta, common iliac-, femoral- and popliteal arteries.	Measured on CT-images acquired at time of inclusion
Other	Contrast to noise ratio (CNR)	Contrast to noise ratio was defined as: (Arterial attenuation - Background attenuation) / Image noise; Arterial attenuation: (see outcome 1) measured in HU digitally by placing a ROI on the CT-images in the aorta, common iliac-, femoral- and popliteal arteries.; Background attenuation: defined as attenuation in muscle measured in HU digitally by placing an identical size ROI on the CT-images in muscle tissue at the same anatomical levels as the arterial measurements.; Image noise: see outcome 4	Measured on CT-images acquired at time of inclusion
Other	Signal to noise ratio (SNR)	Signal to noise ratio was defined as: Arterial attenuation / Image noise; Arterial attenuation: (see outcome 1) measured in HU digitally by placing a ROI on the CT-images in the aorta, common iliac-, femoral- and popliteal arteries.; Image noise: see outcome 4	Measured on CT-images acquired at time of inclusion
Primary	Mean arterial attenuation	Attenuation (x-ray density) is measured in Hounsfield units (HU) digitally by placing a "region of interest" (ROI) circle in the Aorta, common iliac-, femoral- and popliteal arteries on the CT images acquired at the time of inclusion.	Measured on CT images acquired at time of inclusion
Secondary	Subjective examination quality	Examination quality rated by interventional radiologists on a 4-point scale at the anatomic levels: aorta, common iliac, femoral, popliteal- and calf arteries.; Subjective examination quality rating scale: (best) - Excellent: The demarcation of the vessel lumen is excellent, more than sufficient for confident diagnosis or exclusion of stenosis or occlusion.; - Good: The demarcation of the vessel lumen is sufficient for confident diagnosis or exclusion of stenosis or occlusion.; - Adequate: The demarcation of the vessel lumen is adequate for diagnosis or exclusion of stenosis or occlusion, but with limited confidence.; (worst) - Non-diagnostic: There is insufficient demarcation of the vessel lumen for diagnosis or exclusion of stenosis or occlusion.	Rated on CT images acquired at time of inclusion
Secondary	Rate of diagnostic quality angiography	Based on measurements of attenuation in the aorta, common iliac-, femoral- and popliteal arteries. Diagnostic quality defined as arterial attenuation >200 Hounsfield units (HU)	Measured on images acquired at time of inclusion