Digital Mammography Quality Control Manual: Tests, Phantoms and Schedules

Structure of a mammography quality control programme

A programme normally has three layers. Acceptance testing is performed once, after installation or major repair, to prove the unit meets its specification and your protocol. Constancy testing then checks that performance stays within limits through routine tests of increasing depth. Finally, periodic reviews audit image quality, dose and repeat rates.

Responsibility is shared: technologists perform the frequent simple tests, the medical physicist carries out the detailed tests, and the radiologist reviews image quality. The manual should name who does each test, which form records it and what action follows a failure.

Standards and accreditation references

Common references are the European guidelines for quality assurance in breast screening (EUREF), the ACR mammography accreditation programme and its quality control manual, and the IEC 61223-3-2 standard for acceptance tests of mammographic X-ray equipment. Which one applies to your facility depends on your regulator and your accreditation choice.

ACR mammography accreditation is a voluntary programme originating in the United States, and some UAE facilities follow it or similar international schemes. Confirm current UAE requirements with the relevant authority (MOHAP, DHA or DOH) and with your medical physicist before you finalise the manual.

Mammography QC tests: typical daily to annual schedule

Exact lists differ between protocols, so use this as a framework. Daily and weekly tasks usually include cleaning, visual checks, a phantom image or flat-field image to check uniformity and artefacts, and display and workstation checks. Monthly tasks often include compression force and thickness indication checks and review of repeat rates. Annual tasks, carried out by the physicist, cover tube output, half-value layer, automatic exposure control performance, detector response, geometry, dose estimates and image quality assessments.

Whichever protocol you adopt, record results in a trend chart, so that a slow drift is seen before it fails.

• Daily or weekly: artefact and uniformity check, phantom image, monitor check
• Monthly: compression check, repeat analysis, visual inspection
• Annual and after repair: physicist tests of tube, AEC, detector, geometry, dose

Mammography phantom: what it is used for

A mammography phantom is a test object made of breast-equivalent material with embedded details such as fibres, specks and masses of various sizes. Imaged under defined conditions, it gives a repeatable measure of contrast and detail visibility and lets you compare results over time or between units. Some phantoms also allow checking of the AEC response across thicknesses.

Tomosynthesis requires phantoms or protocols suitable for 3D, and you should ask whether your supplier provides QC tools or procedures for it. The Villa Melody IIID TS has integrated tomosynthesis with three scan angles, so its QC plan must include tomosynthesis tests as well as 2D.

What to request from the supplier

Ask for the service manual sections that describe calibration, the factory acceptance data, a list of the tests recommended by the manufacturer, and support for your physicist during acceptance testing. Verify that detector calibration procedures, described in our article on mammography machine maintenance, are included in the service scope. The Melody IIID has density-based automatic exposure control and Smart Micro Press compression, both of which should appear in the QC schedule.

Beckfinity's specialists can supply documentation, coordinate acceptance testing with your physicist and arrange maintenance visits. Request a quote or a consultation to plan the QC programme alongside the purchase.