Dual-energy imaging is an advanced imaging technique, which has become one of the forefronts in the recent CT technology. It can increase the amount of information about the tissue by applying X-rays at two different energies. With Toshiba’s unique Dual Energy helical scanning, exposure is only from the tableside of the patient. This technique not only reduces the dose, but also minimizes exposure to radiosensitive organs such as the breasts and eye lens to provide safer exams to patients.
What is dual energy?
CT imaging is based on the principle that various anatomical structures within the body attenuate X-rays differently. Unfortunately, structures with similar Hounsfield units (CT numbers) remain very difficult to differentiate from each other.
However, structures that produce similar Hounsfield units at one beam energy may respond differently at another. Dual energy scanning can increase the amount of information available from CT imaging. For example, uric acid in renal calculi can be readily identified by analyzing images acquired at both 135 kVp and 80 kVp.
Toshiba's Aquilion ONETM dual energy
Toshiba's Dual Energy approach takes advantage of the accuracy provided by the temporally uniform image volumes created by Aquilion ONE's 16 cm coverage.
Dual energy imaging in Aquilion ONE features:
- Image noise matching
- kV and mA switching ensures consistent image quality for all data sets
- Perfectly synchronized rotations at each kVp
- Whole organ coverage eliminates table motion an improves accuracy
- Proven Quantum V detector data acquisition
Dual Energy Result
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Noise matching by kV and mA switching
The Aquilion ONE dual energy scan mode automatically adjusts the mA settings for each kVp to provide image volumes with similar noise characteristics to ensure accurate dual energy analysis.
Low kV high mA High kV low mA
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Volumetric dual energy advantage
The Aquilion ONE's 16 cm of detector coverage enables acquisition of whole organs in a single rotation. Consequently, two temporally uniform volume scans¸ are acquired with synchronized rotations and no couch top movement. This ensures high quality-images for accurate dual energy analysis.
Scan information - dual energy volume:
- Two volume scans with different kV are acquired
- mA can be set independently
- kV switch time is < 1s
- Scan starts are synchronized
- Except from cardiac, any organ can be scanned
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Scan information - dual energy helical:
- One helical scan is made during which energy switches between low and high kV
- To completely cover the region by both energies a low pitch is used
- Exposure can be turned off at the front side of the patient to minimize dose to the breast area
- When kV is switched also the mA can be adjusted to achieve identical noise levels in both scans
- Dual energy helical scans can be made for all rotation speeds under 1s
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