Aneurysm, Arteriovenous Malformations, Dural Arteriovenous Malformations, Stenosis
Conditions
Keywords
X-ray, Image processing, Neuro angiography, Radiation exposure
Brief summary
ClarityIQ is a novel X-ray imaging technology, that combines advanced real-time image noise reduction algorithms, with state-of-the-art hardware to reduce patient entrance dose significantly. This is realized by anatomy-specific optimization of the full acquisition chain (grid switch, beam filtering, pulse width, spot size, detector and image processing engine) for every clinical task individually. Furthermore, smaller focal spot sizes and shorter pulses are used, which are known to positively influence image quality . The final effect on the clinical image quality is investigated in this study.
Detailed description
The advent of interventional neuroradiology (INR) has changed the treatment of neurovascular diseases by reducing the procedural invasiveness and the recovery time needed by patients, thus improving clinical outcome. However, INR procedures often require many high-quality digital substraction angiography (DSA) runs and long total fluoroscopy times, which can result in patients being exposed to considerable radiation doses levels. In order to introduce a dose reduction technology the most important aspect is to validate the diagnostic image information. Philips has developed a real-time noise reduction algorithm for DSA in neuroradiology that is capable to reduce the patient entrance dose by 75% without loss of image quality.
Interventions
RADIATIONLow dose DSA (75% reduction compared to normal dose) with novel X-ray imaging technology.
Digital substraction angiography (DSA) with reduced dose settings (75% reduction expected) in combination with conventional X-ray imaging technology.
RADIATIONNormal dose DSA with conventional X-ray technology
Digital substraction angiography (DSA) with normal dose settings in combination with conventional X-ray imaging technology.
Sponsors
Philips Medical Systems
Karolinska University Hospital
Study design
Allocation
NON_RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
DIAGNOSTIC
Masking
DOUBLE (Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to 80 Years
Healthy volunteers
No
Inclusion criteria
* Age 18-80 * Normal kidney function * Neurologically intact * Planned for diagnostic angiography or endovascular treatment
Exclusion criteria
* Pregnancy * Other conditions that limit the use of contrast media or ionizing radiation
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Image Quality. For Each Included Participant 2 Images (1 AlluraXper; 1 AlluraClarity) Were Evaluated. | 1 day | The images were evaluated in randomized, blinded, offline readings. The anonymized images were displayed in pairs, i.e. the reference image run on one monitor (randomly left or right side) with the corresponding quarter-dose image run on the adjacent monitor. Three neuroradiologists graded the arterial, capillary, and venous phases separately. For each characteristic the images quality (IQ) were rated on a scale of 1 to 5 as 1 (very poor), 2 (mediocre), 3 (average), 4 (good), 5 (very good/excellent). An overall IQ score (3-15) was calculated as the sum of the score for these characteristics. A paired Student's t test is used to compare the overall IQ score between the 2 imaging techniques. If the upper limit of the 97.5% one-sided CI for the difference overall IQ between the two treatment groups does not exceed the pre-defined non-inferiority margin of 2.5 Clarity will be declared non-inferior to the current image acquisition settings for DSA. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Radiation Dose Measurements: Dose Area Product (DAP) | Participants were followed for the duration of the procedure | Percentage of dose reduction of ClarityIQ vs. AlluraXper in Dose Area Product (DAP) calculated by DAP/frame. |
Other
| Measure | Time frame | Description |
|---|---|---|
| Radiation Dose Measurements: Air Kerma (AK) | Participants were followed for the duration of the procedure | Percentage of dose reduction of ClarityIQ vs. AlluraXper in Air Kerma (AK) calculated by AK/frame. |
Countries
Sweden
Participant flow
Recruitment details
The enrollment of patients occurred between 22 June 2011 and 11 August 2011
Pre-assignment details
20 patients enrolled the study; 16 patients were undergoing diagnostic neuroangiography and 4 were undergoing INR procedures for different pathological conditions. All signed patient consent.
Participants by arm
| Arm | Count |
|---|---|
| AlluraXper - ClarityIQ Angiogram with AlluraXper followed by angiogram with ClarityIQ | 20 |
| Total | 20 |
Baseline characteristics
| Characteristic | AlluraXper - ClarityIQ |
|---|---|
| Age, Continuous | 56 years STANDARD_DEVIATION 11 |
| Region of Enrollment Sweden | 20 participants |
| Sex: Female, Male Female | 7 Participants |
| Sex: Female, Male Male | 13 Participants |
Adverse events
| Event type | EG000 affected / at risk |
|---|---|
| deaths Total, all-cause mortality | — / — |
| other Total, other adverse events | 0 / 20 |
| serious Total, serious adverse events | 0 / 20 |
Outcome results
Primary
Image Quality. For Each Included Participant 2 Images (1 AlluraXper; 1 AlluraClarity) Were Evaluated.
The images were evaluated in randomized, blinded, offline readings. The anonymized images were displayed in pairs, i.e. the reference image run on one monitor (randomly left or right side) with the corresponding quarter-dose image run on the adjacent monitor. Three neuroradiologists graded the arterial, capillary, and venous phases separately. For each characteristic the images quality (IQ) were rated on a scale of 1 to 5 as 1 (very poor), 2 (mediocre), 3 (average), 4 (good), 5 (very good/excellent). An overall IQ score (3-15) was calculated as the sum of the score for these characteristics. A paired Student's t test is used to compare the overall IQ score between the 2 imaging techniques. If the upper limit of the 97.5% one-sided CI for the difference overall IQ between the two treatment groups does not exceed the pre-defined non-inferiority margin of 2.5 Clarity will be declared non-inferior to the current image acquisition settings for DSA.
Time frame: 1 day
| Arm | Measure | Group | Value (MEAN) |
|---|---|---|---|
| AlluraXper | Image Quality. For Each Included Participant 2 Images (1 AlluraXper; 1 AlluraClarity) Were Evaluated. | Investigator 1 | 9.4 Scores on a scale |
| AlluraXper | Image Quality. For Each Included Participant 2 Images (1 AlluraXper; 1 AlluraClarity) Were Evaluated. | Investigator 3 | 11.1 Scores on a scale |
| AlluraXper | Image Quality. For Each Included Participant 2 Images (1 AlluraXper; 1 AlluraClarity) Were Evaluated. | Investigator 2 | 13.1 Scores on a scale |
| Allura Clarity | Image Quality. For Each Included Participant 2 Images (1 AlluraXper; 1 AlluraClarity) Were Evaluated. | Investigator 1 | 11.9 Scores on a scale |
| Allura Clarity | Image Quality. For Each Included Participant 2 Images (1 AlluraXper; 1 AlluraClarity) Were Evaluated. | Investigator 2 | 14.1 Scores on a scale |
| Allura Clarity | Image Quality. For Each Included Participant 2 Images (1 AlluraXper; 1 AlluraClarity) Were Evaluated. | Investigator 3 | 12.1 Scores on a scale |
Secondary
Radiation Dose Measurements: Dose Area Product (DAP)
Percentage of dose reduction of ClarityIQ vs. AlluraXper in Dose Area Product (DAP) calculated by DAP/frame.
Time frame: Participants were followed for the duration of the procedure
Population: All patients with recorded dose information and images for both angiograms were included (n=20)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| AlluraXper | Radiation Dose Measurements: Dose Area Product (DAP) | 72.4 percentage of dose reduction | Standard Deviation 1.95 |
Other Pre-specified
Radiation Dose Measurements: Air Kerma (AK)
Percentage of dose reduction of ClarityIQ vs. AlluraXper in Air Kerma (AK) calculated by AK/frame.
Time frame: Participants were followed for the duration of the procedure
Population: All patients with recorded dose information and images for both angiograms were included (n=20)
| Arm | Measure | Value (MEAN) | Dispersion |
|---|---|---|---|
| AlluraXper | Radiation Dose Measurements: Air Kerma (AK) | 74.6 percentage of dose reduction | Standard Deviation 0.9 |