Our Perfectly Attuned
CT Imaging ChainEmpowering low-dose precision medicine for everyone, everywhere
The CT imaging chain is the heart of how CT images are generated. The pieces work together to give you high image quality at fast scan speeds while keeping dose low – invaluable for your daily work. That is why we have created an imaging chain in which all parts work cohesively. Working together, the CT imaging chain provides advantages in diagnostics and can help you speed up clinical workflows. Continue reading to learn about the benefits of each part and how they can help you in your daily work.
The CT imaging chain includes:
- Low kV imaging with high-power technology
- Spectral shaping with Tin Filter
- Low-noise detectors with our well-known Stellar technology and our new photon-counting QuantaMax detectors - completely free of electronic noise
- Spectral imaging for our whole portfolio
Low kV Imaging with high-power Technology
If you use low kV imaging and high-power technology, then you already know the key major benefit –
producing high quality images with enhanced low-contrast resolution, helping you reduce radiation and contrast media dose. The basis for low kV imaging is the mass attenuation coefficient, which depends on the chemical composition and density of a material. In the past, it was not possible to keep image quality constant at all kV levels, as the X-ray tubes were not powerful enough to produce sufficient tube current (mA) at low kV levels.
Today, however, all our CT scanners from the SOMATOM® and NAEOTOM® lines are equipped with X-ray tubes that are powerful enough to produce high mA at low kV.
This gives you the following added benefits:
- Low kV imaging is no longer limited to small-sized patients – that includes even challenging bariatric cases.
- The cost per examination is reduced without excluding kidney-impaired patients – with a solution that helps you minimize the need for contrast media.
- With technology like CARE kV and CARE keV, system automatically selects the tube voltage for multiple clinical applications across wide range of kV settings.
- For NAEOTOM system contrast enhancement can also be achieved at any kV levels through the use of monoenergetic keV levels.
These benefits are the reason that low kV imaging and high-power technology make up an essential part of our CT imaging chain. In combination with intelligent technology – like CARE kV – low-dose CT imaging has become easier for patients of all sizes, providing invaluable diagnostic information.
See the difference for yourself by checking out the clinical examples at the end of the page.
Spectral Shaping – Tin Filter Technology
Spectral shaping is available across our entire fleet of SOMATOM and NAEOTOM scanners. This is due to its high clinical value in the CT imaging chain:
- Tin Filter improves the spectrum for dedicated CT applications where medium energy photons are not of interest – in particular, non-enhanced examinations such as lung, sinus, or bone imaging.
- Spectral shaping with Tin Filter technology allows our scanners to achieve dose levels of around 1.0 mGy. This is comparable with that of conventional radiography – which is far below the required threshold in lung cancer screenings.
- Spectral shaping enables improved suppression of bone beam hardening, even on metal artifacts from implants or casts when using Tin Filter – all without increasing reconstruction time.
See specific examples of this interaction at the clinical images section at the end of the page.
High-resolution Imaging – Thin-slice Technology and Quantum HD
Thin-slice technology gives our CT imaging chain an extra edge by providing thin rows over the entire detector without collimating the selection. Acquiring these sub-mm slices does not compromise the detector coverage, scan speed, or time – providing you with optimal CT scan image processing. This process can be found in both of our CT imaging families: in scanners which use traditional energy integrating detectors like SOMATOM and NAEOTOM Alpha®, the world’s first photon-counting CT.
Our Stellar detector can be found in our SOMATOM fleet. It is state-of-the-art and a major player in our CT imaging chain when it comes to high-resolution. By combining photodiodes and ADCs in one ASIC, the Stellar detector has immediate benefits in traditional CT imaging:
- The Stellar detector uses approximately 70% less power and dissipates less heat than conventional detectors.
- It enables TrueSignal technology for a substantial reduction in electronic noise.
- It provides up to 3x more range than a conventional detector (up to 102 dB) thanks to HiDynamics for differentiating grey and white matter as well as lesion detection.
- It has an increased channel density of 17% for a finer sampling of small details – which is especially important for those bony structures thanks to thin-slice technology.
With NAEOTOM Alpha, the world’s first photon-counting CT scanner, CT images are processed quite differently. This technology signifies a quantum leap from conventional, energy-integrating CT detectors.
- By converting photons directly into electrical impulses — and bypassing the intermediate step of scintillation light — the septa used to avoid optical cross talk between neighboring pixels become redundant and are therefore removed. This optimizes the dose efficiency of the detector, especially in ultra-high resolution CT imaging.
- As photon-counting detectors measure electrical impulses instead of the light impulses created through scintillation, these detectors are able to clearly distinguish between signals created by X-ray photons-, and electronic noise — and subsequently eliminate the latter.
Compared to a high-end conventional CT scanner, the QuantaMax detector produces roughly ten times as much raw data with the same detector area. The result is highly detailed clinical images — with a slice thickness of as low as 0.2 mm, containing spectral results for every exam, free of electronic noise, and with higher contrast-to-noise ratio. This enables unprecedented clinical insights.
See specific examples at the clinical images section at the end of the page.
Spectral Imaging
Spectral imaging, or Dual Energy, is available throughout the entire portfolio of Siemens Healthineers CT scanners. It has a wide range of benefits that make up an integral part of our CT scan imaging chain:
- Produce image sets with two different X-ray spectra to characterize materials while highlighting abnormalities.
- Gain access to clinical information that goes beyond morphology to early detection of diseases that enable earlier treatment.
- Use it for a variety of different applications, such as assessing lung perfusion defects, differentiating brain hemorrhage, and more.
- Get Dual Energy images with the dose level of a single source acquisition performed with conventional 120 kV.
- For NAEOTOM system Quantum Spectral Imaging further supports clinical decision making by providing spectral results at a high level of detail, at any tube voltage and at full scan speed and temporal resolution.
Depending on the CT scanner you have, there are different methods of performing spectral imaging. The following video clips show you the inherent differences between them.
If your curiosity is still not sated, then be sure to take a look at the clinical images below.
NAEOTOM Alpha redefines the way we know spectral imaging. The world’s first photon-counting CT is capable to count the charges created by individual X‐ray photons as well as measuring their energy level, therefore keeping intrinsic spectral sensitivity in every scan while maintaining the highest temporal resolution provided by its Dual Source technology.
See specific examples at the clinical images section at the end of the page.
Clinical case gallery
Courtesy: Data on file
1) Cinematic VRT performed with syngo.via
Occlusion of the abdominal aorta in an obese patient
Single-phase contrast-enhanced CT scan
SOMATOM go.Top
90 kV
CTDIvol: 15.21 mGy
• Low-kV imaging even in obese patients
Courtesy of The Ohio State University Wexner Medical Center
Follow-up after fusion and fixation in an obese patient
Tin Filter scan
SOMATOM go.Top
Sn140 kV
CTDIvol: 15.75 mGy
- High-kV Tin Filter scanning surpresses metal artefact efficiently
Courtesy of Erlangen University Hospital, Erlangen, Germany
Two-step thorax and abdomen imaging with i.v. contrast media application (1/2)
SOMATOM go.Up
Scan parameters: 130 kV
CTDIvol: 3.1 mGy
- Multiple infiltrates and lesions with cavities clearly visualized
Courtesy of Erasmus Medical Center Rotterdam, Rotterdam, The Netherlands
Imaging of severity of the acute pulmonary embolism
NAEOTOM Alpha
120 kVp
CTDIvol: 3.74 mGy
