1. The X-ray tube is the headline risk

A CT tube is a consumable with a finite life, and a replacement is one of the largest single costs in the CT lifecycle. The tube is therefore the first thing to establish, not the last.

  • Ask for the tube's accumulated exposure — usually expressed as scan seconds, mAs or exposure counts depending on the manufacturer.
  • Ask whether the tube is original or a replacement, and if replaced, when and with what (OEM, refurbished or third-party).
  • Ask for the expected life of that tube type and compare it against the accumulated figure.
  • Budget for a replacement if the tube is past roughly two-thirds of its expected life. Treat that budget as part of the purchase price.

A cheap scanner with an exhausted tube is not cheap. A slightly more expensive scanner with a recently replaced tube often is.

2. Slice count and detector rows

Detector rows determine coverage per rotation and therefore clinical scope. Broadly: 16-slice systems suit routine head, spine and general body imaging; 64-slice systems open up CT angiography and better volumetric work; 128 slices and above support cardiac and demanding vascular protocols. Match the configuration to the clinical work actually planned, not to the most impressive number available.

Be careful with marketing designations. Some systems described by a slice number achieve it through reconstruction techniques rather than physical detector rows. Ask for the physical detector configuration.

3. Detector condition

Detector modules degrade and individual channels can fail, producing ring artefacts that calibration cannot fully remove. Ask when the detector was last calibrated, whether any modules have been replaced, and whether there is any known artefact. Review recent phantom images if available — a uniformity phantom will reveal ring and streak artefacts quickly.

4. Gantry, table and mechanics

Check rotation smoothness and noise, slip-ring condition, table travel accuracy and load rating, and the condition of covers and the patient-facing surfaces. Table positioning accuracy matters clinically; a table that has drifted out of calibration or shows mechanical play is a repair, not a cosmetic issue.

5. Software version, options and licences

As with MRI, note the platform release and the licensed application packages: cardiac, dual-energy where applicable, perfusion, dental, advanced vessel analysis, iterative reconstruction and dose-reduction packages. Iterative reconstruction in particular has a direct effect on dose and image quality, and is licensed separately on many platforms.

Confirm licence transferability to a new owner and site, and confirm the version is still supported by the manufacturer or by a qualified third-party service provider.

6. Console, workstation and connectivity

Confirm what is included: acquisition console, reconstruction hardware, any separate post-processing workstation, and the DICOM options needed to connect to a PACS or RIS. Check for DICOM Store, Query/Retrieve, Modality Worklist and Structured Reporting as required by your workflow. Missing connectivity licences are a common and easily avoided delay at commissioning.

7. Logs, error history and utilisation

Request service history, error logs, and the number of scans or operating hours. Look for repeated faults in the same subsystem, a pattern of tube arcing, cooling faults or gantry errors. A single dramatic incident that was properly repaired is usually less concerning than a long tail of the same recurring error.

8. Dose, quality assurance and acceptance

Ask for the most recent quality assurance and dose measurements, and for the acceptance or constancy test reports required in the seller's jurisdiction. At the destination, most countries require radiation authority notification or authorisation and an acceptance test by a qualified medical physicist before clinical use. Plan and budget for that step.

9. Site and infrastructure fit

CT rooms are simpler than MRI rooms — there is no Faraday cage — but they still need lead shielding designed by a qualified expert, adequate power and stable supply, room cooling sized to the heat load, floor loading capacity, and an access route wide enough for the gantry. Confirm the gantry can physically reach the room before purchase.

10. Commercial terms worth fixing in writing

  • Tube condition and, if relevant, a tube warranty or price adjustment mechanism
  • What is included: consoles, workstations, injector, phantoms, accessories, spare parts
  • Deinstallation, packing, transport and insurance responsibility
  • Delivery terms, and the point at which risk and title transfer
  • Installation, calibration and acceptance testing responsibility
  • Warranty scope and duration, and what happens if the system fails acceptance

Quick summary

  • Establish tube exposure and remaining life first — it dominates the economics
  • Confirm physical detector rows, not marketing slice numbers
  • Look for ring artefacts and ask about detector module replacements
  • Check which software and DICOM options are licensed and transferable
  • Read the error logs for recurring faults
  • Budget for shielding design, acceptance testing and physicist sign-off at destination

Frequently asked questions

How long does a CT X-ray tube last?

Tube life varies widely by tube type, scanner model and workload, and manufacturers express it in scan seconds, mAs or exposure counts rather than years. The practical approach is to ask for the accumulated figure and the expected life for that specific tube type, then treat anything past roughly two-thirds of expected life as a replacement to budget for.

Is a 16-slice CT still worth buying?

For routine head, spine, chest, abdomen and general body imaging, a well-maintained 16-slice system remains clinically capable and is often the most cost-effective option. It becomes limiting for cardiac CT, demanding CT angiography and high-throughput trauma work, where 64 slices or more is the practical minimum.

What is the difference between refurbished and used CT?

'Used' generally means sold in its current condition, as removed from the previous site. 'Refurbished' implies a defined process — inspection, replacement of worn parts, cleaning, reassembly, calibration and testing against specification, with documentation. Because terminology is used loosely in the market, ask for the actual scope of work performed and the test results rather than relying on the label.

What does a used CT scanner cost to install?

Beyond the equipment price, plan for deinstallation and rigging, transport and insurance, customs and duties, room preparation including lead shielding designed by a qualified expert, electrical and cooling works, installation and calibration, acceptance testing by a medical physicist, and the first year of service cover. These items commonly total a significant fraction of the equipment price.

Related guides

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Checklist for Buying a Used MRI Scanner

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How to Identify a Medical Imaging Spare Part

How to identify MRI coils, CT tubes, detectors, boards and workstation components from labels and part numbers, what to .

 Regulatory

Importing Refurbished Medical Imaging Equipment

What to check before importing a used or refurbished MRI or CT scanner.

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Published 2026-08-12 by Radiology Invest Group, Bucharest, Romania. General information for planning purposes; always confirm requirements against the equipment manufacturer's documentation and the applicable authority at your destination.