Model note · CT Scanner
Siemens SOMATOM Definition AS / AS+
SOMATOM Definition AS is Siemens Healthineers' single source multislice CT. Configurations scale from 20 to 128 slices, and an on site upgrade path lets one gantry grow with the department. It has been sold new and as Siemens refurbished ecoline units for well over a decade, so it is a common workhorse CT. Most of its recall history is software, with several gantry cover hardware actions.
The model
Maker, model and type.
- Maker
- Siemens Healthineers (Siemens Healthcare GmbH / Siemens Medical Solutions USA, Inc.)
- Model
- SOMATOM Definition AS / AS+ (model 8098027)
- Device type
- CT Scanner
- Main document
- Open the public document
Key specifications
What the public record says.
| Item | Value | Source |
|---|---|---|
| Slice configurations | 20, 40, 64 and 128 slice versions, upgradable on site from 20 to 128 slices | Source |
| Fastest rotation time | 0.28 s (added with software syngo VA48) | Source |
| Scan speed and temporal resolution (manufacturer) | Up to 23 cm/s coverage; 150 ms temporal resolution | Source |
| Table load | Up to 676 lb (about 307 kg) | Source |
| Detector | Stellar detector option with dynamic range up to 102 dB; 0.5 mm slices | Source |
| Lowest tube voltage mode | 70 kV scan mode | Source |
| Footprint | 193.7 square feet (about 18 square metres) | Source |
| FDA classification | Computed tomography X-ray system, 21 CFR 892.1750, Class II, product code JAK | Source |
| Software clearance example | K143400, syngo VA48 (SOMARIS/7 VA48), decided 8 April 2015, adding TwinBeam dual energy and adaptive spiral for sliding gantry | Source |
| Dose and artefact options | CARE Dose4D, HandCARE, ADMIRE iterative reconstruction, iMAR and MARIS metal artefact reduction | Source |
Recalls
Known FDA recalls.
- Z-0473-20222021-11-19
Software VB20_SP5 could seriously degrade head image quality.
FDA record - Z-0284-20222021-08-30
syngo.CT VB20 to VB20_SP4 workflow interruptions causing delays, rescans or extra contrast.
FDA record - Z-0406-20202019-10-07
syngo CT VB20 scan aborts and system crashes across SOMATOM models.
FDA record - Z-1745-20182017-11-08
CARE Dose4D software issue risking unnecessary radiation exposure.
FDA record - Z-0604-20172016-10-19
Laser light marker windows in the front cover could loosen or drop out.
FDA record - Z-2624-20162016-07-13
Firmware and software communication error meant the injector did not start in coupled mode.
FDA record - Z-0929-20092008-12-09
Possible improper installation of the tilt transport lock or tilt limiter.
FDA record
Safety
Safety warnings from the record.
- Reaching through an open laser window in the front cover can expose a person to rotating or electrical gantry parts. Source
- Software faults on this platform have been linked to rescans with extra dose, extra contrast and, in the worst case, accidental radiation to the user. Source
- A CARE Dose4D software issue could expose patients to unnecessary radiation. Source
Sources
Where this note comes from.
- Siemens Healthineers SOMATOM Definition AS page (ecoline, US)
- FDA 510(k) K143400 summary, SOMATOM Definition AS/AS+ with syngo VA48
- openFDA recall search, Definition AS
- openFDA MAUDE problem counts, brand SOMATOM Definition AS
Not covered: Gantry bore, generator power and X-ray tube type were not given on an official page that could be opened (the ecoline page shows a garbled bore figure, so it is omitted). Siemens service documentation and error messages are not public, so errorCodes is empty. Over 20 recall records exist, mostly software; only representative ones are listed. Recall text was read through openFDA because FDA recall pages returned errors at drafting time.
BMEssentia knowledge drafted from public information, reviewed by Hasan Khaled Ismail on 2026-10-24. Always follow the manufacturer's instructions for use and service manual.
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