Important Note: This site is designed to work best in Firefox, Safari or Chrome. Please update your browser to view the complete site.

Cardius® X-ACT

It’s faster, it’s lower dose, and it’s got one serious size advantage.

The Digirad Cardius® X-ACT provides higher clinical quality, faster imaging, lower dose, reduced operational costs and a solid pathway to the future.

X-ACT Advantage:

  • Solid-State: Three flat panel detectors used for acquisition of both gamma ray and x-ray
  • Effective: Fluorescence attenuation correction improves diagnostic confidence
  • Protective: Triple-head detector geometry reduces patient dose by 3X
  • Compact: Can be used in rooms as small as 8’ x 9’
  • Patient-centric: Enhanced comfort for obese or claustrophobic patients
Request a Consultation ➝ Download a Brochure ➝


The Cardius® X-ACT diagnostic imaging system raises the bar in nuclear cardiac imaging with its advanced SPECT/FAC technology.

With its triple-head, solid-state detectors and proprietary fluorescence attenuation correction, the X-ACT allows for greater speed and throughput, high precision, and superb reliability.

The system’s high-definition, solid-state (HDSD) detectors, together with our nSPEED™ software enable a 3X reduction in patient dose or three times faster imaging time compared to conventional dual-head systems. And with its compact design, Cardius X-ACT can be used in rooms as small as 8’x 9’ (72 sq. ft.) without the need for room shielding or architectural modifications. Plus, the patient-friendly, open gantry design provides greater comfort for patients up to 500 pounds, as well as bariatric, claustrophobic and COPD patients.

Attenuation Correction


The X-ACT elevates the performance and clinical confidence of myocardial perfusion imaging studies (MPI) to a level that was unimaginable, until now. Rapid emission imaging is made possible through the use of Digirad’s proprietary high count-rate, solid-state high-definition detectors (HDSD); high-efficiency triple-head geometry; high sensitivity fanbeam collimators; and rapid 3D-OSEM reconstruction techniques. Rapid transmission imaging is made possible by the use of a novel mono-energetic X-ray line source. Not only is imaging fast, but the images are of consistent outstanding quality, patient to patient, day after day.

The X-ACT represents an advanced genre of fully-integrated SPECT/FAC designs where high-speed solid-state detectors have the ability to collect both the emission and the transmission data, eliminating the need to move the patient between the emission and transmission data collections, providing greatly improved registration accuracy and efficiency over alternative in-line SPECT/VCT approaches. The 27 inch [69cm] wide FOV low dose fluorescence attenuation correction approach delivers 80 times more counts than isotopic techniques with 3.5 times less noise during a short, 1 minute scan that encompasses approximately 10 to 15 respiratory cycles. The results, the transmission images are free of truncation or beam hardening artifacts and the respiratory co-registration of the E/T data sets is excellent. These are key reasons why the quality of studies performed on the X-ACT are so good. To top it off, the patient radiation exposure is a low 5 microsieverts, or nearly 100 to 1,000 times lower than other commercially available CT-based AC approaches.

The open upright design of the X-ACT makes the system very patient- friendly, which is a big contrast from the deep tunnel-like supine imaging designs of other SPECT/CT systems. The open design and wide orbit radius enables you to image claustrophobic, COPD and bariatric patients up to 500 lbs [227kg]. Since the diaphragm lowers when patients are imaged upright, you also get better separation of the heart from the liver and bowels, so artifacts from overlying activities are significantly reduced. The small size of the detectors mean a patient’s arms do not have to be raised nearly as high, as with ‘Anger’ systems and it is possible to bring the detectors tight to the patient’s chest, ensuring consistent high image quality results, for patients of any size. Patient motion is minimized by use of a saddle-seat that provides passive resistance to sliding and the use of Digirad’s fully-automated STASYS™ motion correction software - and of course, fast imaging.

Attenuation Correction from Digirad

The Co-Registered Transmission/Emission and Short Axis Slices images above display how an image appears with and without Attenuation Correction



High statistical precision with up to 1,000x less AC patient radiation exposure.


Patient-friendly, open and upright design allows for easy access for patients up to 500 lbs.


No movement of patient between emission & transmission images increases co-registration accuracy.


The solid-state triple-head design with nSPEED™ 3D-OSEM reconstruction and integrated attenuation correction reduces total imaging time


No truncation or beam hardening artifacts with wide 27” [69cm] transverse beam and use of novel mono-energetic fluorescent X-ray line source.


Compact, lightweight design less than 1,000 lbs [454kg]. Only 8 ft. X 9 ft. room required [2.4m X 2.7m]. No lead shielding required. Only 20Amp/110V electrical.


Superb clinical performance and reliability with high-definition solid-state detectors. Enabling technology for future protocols.

Digirad — Revolutionary solid-state nuclear cardiology equipment and services.

Making Healthcare Convenient. As Needed. When Needed. Where Needed.