IQ•SPECTThe art of minimizing dose while maximizing speed
A key trend in nuclear medicine is the ever-increasing demand for faster MPI exams. IQ•SPECT™ is a cardiac imaging solution that uses a combination of converging collimators, modified cardio-centric acquisition, and special reconstruction methods to deliver ultrafast cardiac imaging that is four times faster than conventional SPECT acquisition.
Features & Benefits
Siemens IQ•SPECT is the only technology today that performs ultra-fast cardiac imaging with a general purpose camera. Its unique collimator design, cardiocentric image acquisition and advanced reconstruction technology acquires four times more counts than conventional methods for high quality images independent of age, body shape or size. With IQ•SPECT, physicians can perform a myocardial perfusion imaging study in approximately 4 minutes using the standard dose, 8 minutes using half the standard dose or 16 minutes using one quarter of the standard dose.
With its SMARTZOOM collimators, modified cardio-centric acquisition and special reconstruction methods, IQ•SPECT is the solution for fast cardiac imaging using half the dose with twice the speed.
SMARTZOOM
Siemens SMARTZOOM collimators employ the magnifying properties of a cone-beam collimator near the center of the field of view and eliminating truncation at the edges of the field of view similar to a parallel-hole collimator. The unique position and shape of each hole in the collimator, also referred to as a vector map, is measured in the factory at Siemens and stored with the collimator to be used during reconstruction. The result is an increase of up to four-times more sensitivity.
Aquisition
IQ•SPECT positions the heart in the center of the collimator field of view and positions the detectors at a 28 cm radius for the cardiocentric orbit. IQ•SPECT uses the flexibility of the Symbia™ gantry to position each detector at an optimal distance to maximize sensitivity gain and minimize feelings of claustrophobia.
Conventional scanners use parallel-hole collimators and orbits about the center of the gantry. Detectors rotate in close proximity to the patient, often causing feelings of claustrophobia.
IQ•SPECT positions the heart in the center of the collimator field of view and positions the detectors at a 28 cm radius for the cardio-centric orbit. IQ•SPECT uses the flexibility of the Symbia™ gantry to position each detector at an optimal distance to maximize sensitivity gain and minimize feelings of claustrophobia.
Combined with advanced reconstruction, this method allows for a selection of optimized protocol options:
- 4 min, standard dose
- 8 min, half dose
- 16 min, quarter dose
Reconstruction
The advanced IQ•SPECT reconstruction method is a proprietary implementation of a conjugate-gradient iterative reconstruction algorithm. The algorithm is optimized to accurately reflect the measured geometry of the SMARTZOOM collimators and the cardio-centric orbit of the detectors. A 3D measurement of gantry deflection allows correction of gantry motion based image distortions. Measurements of hole size, shape, and pointing direction for all 48,000 holes in the SMARTZOOM collimator ensure accurate image reconstruction.
Conventional reconstruction algorithms do not fully account for detector motions, deflections of the gantry, collimator hole size and shape, and distance from the patient to the detectors. This may result in artifacts and truncation that can affect image quality. For example, gravitational deflections of the detector heads during gantry rotation can potentially degrade tomographic resolution.
After data acquisition is complete the study is transferred to the Symbia.net first user workstation for reconstruction. The advanced IQ•SPECT reconstruction method is a proprietary implementation of a conjugate-gradient iterative reconstruction algorithm. The algorithm is optimized to accurately reflect the measured geometry of the SMARTZOOM collimators and the cardio-centric orbit of the detectors.
A 3D measurement of gantry deflection allows correction of gantry motion based image distortions. Measurements of hole size, shape and pointing direction for all 48,000 holes in the SMARTZOOM collimator enables accurate image reconstruction.
The IQ•SPECT construction method has been developed to achieve the following objectives:
- It maintains the same reconstructed resolution as LEHR collimators in a non-circular orbit
- It realizes the four-fold sensitivity gain of the SMARTZOOM collimator
- It corrects for the effects of patient attenuation, scatter and motion
- It performs reconstruction in a clinically acceptable time
General Requirements
System
- Symbia Evo
- Symbia Intevo
- Symbia Intevo Bold
- Symbia Intevo Excel
- Symbia.net Client Server
- c.cam eco
Other
SMARTZOOM collimators require space in an Integrated Collimator Cart (ICC) or a detached collimator cart. Requires a dedicated, standalone workplace for reconstruction.
Please Note: Additional technical pre-requisites may apply. Upon receiving your request, your local Siemens Healthineers representative will clarify whether your system meets the requirements.
