Computed Tomography, Contrast Media, Hepatic Cancer, Imaging, Pancreatic Cancer
Conditions
Keywords
computed tomography, CT angiography, hepatic imaging, pancreatic imaging, hepatocellular cancer, pancreatic adenocarcinoma, liver, pancreas
Brief summary
To examine inter-subject variations of optimal late arterial phase contrast-enhancement defined as the greatest difference in contrast attenuation of hepatocellular carcinoma (HCC) compared to background liver parenchyma resp. pancreatic lesions compared to pancreatic parenchyma. To evaluate which time-points best depict an optimal late arterial phase.
Detailed description
Background: Many previous studies have analyzed and proposed different strategies to achieve optimal contrast timing and enhancement in the late arterial phase to best depict arterialized lesions in the liver and hypoattenuating tumors in the pancreas(1-12). But even with the use of state-of-the-art protocols, inter-subject variations of optimal contrast enhancement in liver lesions and pancreas parenchyma are still very common. The aim of this study is to first analyze these alterations and to, secondly, use the newly gained knowledge to design a dose-neutral multiple arterial phase protocol. An optimized arterial phase protocol might improve the detection of hepatocellular carcinoma (HCC) and/or pancreatic adenocarcinoma. Purpose: To measure when the greatest difference in attenuation occurs in HCC compared to background liver parenchyma resp. in pancreatic lesions vs. pancreatic parenchyma. To describe the inter-subject variation of these enhancement times and to evaluate at which time-points an optimal late arterial phase can be achieved. The investigators will use the perfusion scanning technique, bolus-tracking and high body-weight-adjusted volumes of contrast media (CM). Anticipated results: The aim is to find the best time points for optimal CM-enhancement in HCC lesions and pancreas parenchyma. The results will show the extent of the inter-subject temporal enhancement differences and will be used to design an optimized late arterial phase protocol for clinical practice and future studies.
Interventions
DIAGNOSTIC_TESTComputed Tomography of the Abdomen
Multi-phasic CT scan of the abdomen: 1 low dose unenhanced scan + 10 low dose arterial perfusion scans + 1 portal-venous phase scan + 1 delayed phase scan. Bolus-tracking threshold in abdominal aorta = 160 HU. Delay of first arterial scan 5 sec after bolus-tracking threshold has been reached; and then 1 scan every 3 sec until 35 sec after threshold. Contrast media (CM) protocol: fixed injection duration: 25 sec, body weight-adjusted CM volume: 750 mgI/kg bodyweight (max 80 kg women, 100kg men), Iomeron 400mgI/ml. Image-reconstruction: Motion-correction, noise-reduction and fusion of the best arterial time points to reconstruct one optimally timed early and one optimally timed late arterial phase.
Sponsors
Karolinska Institutet
Study design
Observational model
ECOLOGIC_OR_COMMUNITY
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
50 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* patients, who are scheduled for a multiphasic liver or pancreas CT because of known or suspected malignancy in the liver or pancreas.
Exclusion criteria
* below 50 years of age, contrast media allergy or decreased kidney function
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Peak enhancement values measured in Hounsfield units(HU) in abdominal aorta. | at the time of intervention (= Multi-phasic CT scan of the abdomen) | Creation of time attenuation curves (TAC) in abdominal aorta. |
| Peak enhancement times measured in seconds in abdominal aorta. | at the time of intervention (= Multi-phasic CT scan of the abdomen) | Creation of time attenuation curves (TAC) in abdominal aorta. |
| Peak enhancement values measured in Hounsfield units(HU) in celiac trunc. | at the time of intervention (= Multi-phasic CT scan of the abdomen) | Creation of time attenuation curves (TAC) in celiac trunc. |
| Peak enhancement times measured in seconds in celiac trunc. | at the time of intervention (= Multi-phasic CT scan of the abdomen) | Creation of time attenuation curves (TAC) in celiac trunc. |
| Peak enhancement values measured in Hounsfield units(HU) in superior mesenteric artery (SMA). | at the time of intervention (= Multi-phasic CT scan of the abdomen) | Creation of time attenuation curves (TAC) in SMA. |
| Peak enhancement times measured in seconds in superior mesenteric artery (SMA). | at the time of intervention (= Multi-phasic CT scan of the abdomen) | Creation of time attenuation curves (TAC) in SMA. |
| Peak enhancement values measured in Hounsfield units(HU) in hepatic artery. | at the time of intervention (= Multi-phasic CT scan of the abdomen) | Creation of time attenuation curves (TAC) in hepatic artery. |
| Peak enhancement times measured in seconds in hepatic artery. | at the time of intervention (= Multi-phasic CT scan of the abdomen) | Creation of time attenuation curves (TAC) in hepatic artery. |
| Peak enhancement values measured in Hounsfield units(HU) in portal vein. | at the time of intervention (= Multi-phasic CT scan of the abdomen) | Creation of time attenuation curves (TAC) in portal vein. |
| Peak enhancement times measured in seconds in portal vein. | at the time of intervention (= Multi-phasic CT scan of the abdomen) | Creation of time attenuation curves (TAC) in portal vein. |
| Peak enhancement values measured in Hounsfield units(HU) in pancreas parenchyma. | at the time of intervention (= Multi-phasic CT scan of the abdomen) | Creation of time attenuation curves (TAC) in pancreas parenchyma. |
| Peak enhancement values measured in Hounsfield units(HU) in pancreatic lesions. | at the time of intervention (= Multi-phasic CT scan of the abdomen) | Creation of time attenuation curves (TAC) in pancreatic lesions. |
| Peak enhancement times measured in seconds in pancreas parenchyma. | at the time of intervention (= Multi-phasic CT scan of the abdomen) | Creation of time attenuation curves (TAC) in pancreas parenchyma. |
| Peak enhancement times measured in seconds in pancreatic lesions. | at the time of intervention (= Multi-phasic CT scan of the abdomen) | Creation of time attenuation curves (TAC) in pancreatic lesions. |
| Peak enhancement values measured in Hounsfield units(HU) in liver parenchyma. | at the time of intervention (= Multi-phasic CT scan of the abdomen) | Creation of time attenuation curves (TAC) in liver parenchyma. |
| Peak enhancement values measured in Hounsfield units(HU) in hepatic lesions. | at the time of intervention (= Multi-phasic CT scan of the abdomen) | Creation of time attenuation curves (TAC) in hepatic lesions. |
| Peak enhancement times measured in seconds in liver parenchyma. | at the time of intervention (= Multi-phasic CT scan of the abdomen) | Creation of time attenuation curves (TAC) in liver parenchyma. |
| Peak enhancement times measured in seconds in hepatic lesions. | at the time of intervention (= Multi-phasic CT scan of the abdomen) | Creation of time attenuation curves (TAC) in hepatic lesions. |
| highest enhancement difference between a hepatic lesion and background liver parenchyma | at the time of intervention (= Multi-phasic CT scan of the abdomen) | To measure the highest enhancement difference in Hounsfield units(HU) between a hepatic lesion and background liver parenchyma |
| time-point of highest enhancement difference between a hepatic lesion and background liver parenchyma | at the time of intervention (= Multi-phasic CT scan of the abdomen) | To depict the time-point of the highest enhancement difference between a hepatic lesion and background liver parenchyma by comparing their tissue attenuation curves |
| highest enhancement difference between a pancreatic lesion and background pancreatic parenchyma | at the time of intervention (= Multi-phasic CT scan of the abdomen) | To measure the highest enhancement difference in Hounsfield units(HU) between a pancreatic lesion and background pancreas parenchyma |
| time-point of highest enhancement difference between a pancreatic lesion and background pancreatic parenchyma | at the time of intervention (= Multi-phasic CT scan of the abdomen) | To depict the time-point of the highest enhancement difference between a pancreatic lesion and background pancreas parenchyma by comparing their tissue attenuation curves |
Countries
Sweden
Outcome results
None listed