Presentation QA Xray eqpmnt

QUALITY ASSURANCE

X-RAY EQUIPMENT

AT BUGANDO MEDICAL CENTRE

INTRODUCTION

The aim of this experiment is to provide:

The technical information and testing routines that will allow simple care, maintenance and testing to be carried out on basic X-ray equipment.

• An insight into the choosing and accepting of basic X-ray equipment.

CHOOSING X-RAY EQUIPMENT

Identify your need; the following are the common needs to identify into the choosing of X-ray equipment:- General purpose, fluoroscopy, specialized, mobile.

• Generator (design/output).
• To suite power supply.
• kV, mA, time rangers.
• Tube mounting (overhead/column).
• Table (tilting, fixed, floating top, Bucky).

Upright Bucky.

Anticipated patient through put.

Resources available

• -Maintenance and repair -Finance
• Manufacture warranty

• -Determine responsibility
• Supplier services

Making the choice

• Establish your specifications requirements.
• Review manufacturer’s specifications.
• Make a short list of suitable equipment.
• Submit your requirements to the selected manufacturers for quotations.
• Review quotations.

Make selection.

Ensure that you have the written agreement of the manufacturer or supplier, to supply and install the equipment chosen, at the price quoted and that there are no hidden extras.

GENERATOR

A generator is a device which is used to produce electric energy.

It is part of the electrical system of an X-ray machine which determines radiation output. Any inconsistency in radiation output will adversely influence the quality of the radiograph.

The kV, mA and time must be consistent on all settings. Many factors can influence the radiation output, the ones to be considered are:

• Fluctuations in the main electrical supply.

Inconsistency or inaccuracies in kVp, mA and time.

Fluctuations in main electrical supply

Most X-ray units have a mains compensator that automatically compensates for mains fluctuations.

However, in some less sophisticated units, this must be done by hand. The radiographer must always check the mains compensator meter before making an exposure and make any corrections necessary.

Example of Specifications or Requirements for the choosing of X-ray equipment.

The following Requirements were made for the choosing of X-ray equipment at Bugando Medical Centre (BMC):

Number

BMC/HQ/G/2018-2019/15/LOT-02

• Quantity
• One machine
• Delivery schedule (shipment) in weeks

10 weeks

Description

X-ray stationary floor mounted digital X-ray System (High Powered Xray Unit for General Radiography with Digital Flat Panel Technology)

Description continue…

• Minimum Technical Specifications or Requirements:
• Generator:
• Max. output power: 80kW or more
• Min. kV: 40kV or less
• Max. kV: 150kV or more
• Min. mA: 10mA or less
• Max mA: 630mA or more
• mAs range: 0.5mAs to 800mAs
• Exposure time: 0.001sec to 9.0sec or more
• Automatic Exposure Control (AEC)

Number of focal spots: at least 2

Minimum Technical Specifications or Requirements continue…

Floor Mounted Tube Support:

• Longitudinal movement of X-Ray tube: min. 2950mm
• Transversal movement of X-Ray tube: min. 1400mm
• Vertical movement of X-Ray tube: min. 1400mm
• Rotation of the X-Ray tube around horizontal axis: min. 1500C/1800C
• Rotation of the X-Ray tube around vertical axis: min. 1200C
• Auto-positioning Function
• Synchronization movement of the X-Ray tube support unit and Bucky stand

Synchronization movement of the X-Ray tube support unit and Bucky table

Minimum Technical Specifications or Requirements continue…

• X-ray Tube:
• Focal spots: at least 0.6/12mm or less
• Max anode heating capacity: 140kHU or more
• Max X-ray tube voltage: 125kV or more
• Multi-function touch screen control
• Wireless Flat Panel Detector with Bucky table
• FDP size: at least (43 x 43) +/- 1cm
• Pixel size: at least 139 x 139 µm
• Matrix size: at least 3052 x 2540

Scintillator: Csl

Battery type: Lithium-ion

Minimum Technical Specifications or Requirements continue…

• Wireless Flat Panel Detector with Bucky stand:
• FDP size: at least (35 x 43) +/- 1cm
• Pixel size: at least 139 x 139 µm
• Matrix size: at least 3052 x 2540

Scintillator: Csl

Minimum Technical Specifications or Requirements continue…

• Digital Radiography Computer System for Radiographer:

At least 19” medical grade display, user interface touch panel/ mouse Software for patient identification, entry, viewing, image processing and post-processing (brightness, rotation, inversion, zoom, pan and measurements) DICOM performance, print and store functions UPS

Minimum Technical Specifications or Requirements continue…

• Accessories:

Voltage Stabiliser

• UPS for digital system (where applicable)
• Lead glass: at least 100 x 80cm

DAP meter

Laser Printer (min. 320DPI and print at least 3 sizes of films online 10 x12, 10 x 14, 11 x 14, 8 x 10 and 14 x 17inches.

Re-installation and Backup software

Minimum Technical Specifications or Requirements continue…

• Documents:
• Service and operation manuals in English language for all items supplied in this lot.

Execution guidance or installation drawings Certificates of compliance to safety norms and standards and/or trial tests results at manufacturer’s facility.

Minimum Technical Specifications or Requirements continue…

• Warranty:
• At least 2 years warranty for all items supplied in this lot

Training:

Provide appropriate training at installation location or site in English language for effective and problem free use of the equipment included in this LOT.

Training programme shall be submitted by the Bidder in the tender and should include schedule, duration, title and description of training materials.

ACCEPTING OF NEW X-RAY EQUIPMENT

• Specifications of equipment installed are the same as that ordered.
• Installation has been carried out as stated in the contract.
• Installation is complete and equipment is working efficiently and to your satisfaction.
• All QC tests have been carried out and are satisfactory.
• All accessory equipment has been supplied and is in good order.

Operating manual has been supplied and is the correct one.

NB: Only when you are sure that the installation has been carried out satisfactorily should you sign the acceptance papers.

Minimum Technical Specifications or Requirements continue…

Standards:

All equipment should be from a branded source with a certified quality assurance system and latest ISO (International Standard Organization) certification

TESTS THAT CAN BE DONE FOR X-RAY EQUIPMENT

• Radiation output reproducibility test
• Constancy of Radiation output at different mA settings test
• Accuracy of timer test

Accuracy of kVp test

In this presentation we were only able to come out with explanation of “Accuracy of timer test” due to the lack of some equipments.

ACCURACY OF TIMER TEST

• An X-ray unit timer is used to measure the exposure time of X-rays.

This test is to check the accuracy of the X-ray unit timer.

This test should only be carried out on a 1 or 2 pulse unit. Timers of 3-phase and capacitor discharge units cannot be checked by this method.

FREQUENCY OF TEST

• At the start of a quality control program.
• Yearly or as necessary.

EQUIPMENT REQUIRED

• Manually operated spinning top.
• One loaded 24×30 cassette.

Two sheets of lead rubber.

METHOD

• We place the cassette on the x-ray table face up.
• We place the spinning top in one quarter of the cassette.
• We cover the other three quarters of the cassette with lead rubber.
• We set a 100cm FFD and collimate to cover the spinning top.
• We set an exposure of 70kV, 100mA and a time of 0.1sec.
• Manually, we spin the top till it has settled to a medium speed and make an exposure
• NB: It maybe necessary to experiment before starting the test.
• Repeat the process on each of the remaining quarters of the film.

We process the film.

EVALUATION

The film supposed to show four images, each having a series of spots forming an arc. But we were only able to expose two of four quarters of the film.

• The spots are easily counted, they are not allowed to complete a circle and overlap.

The accuracy of timer is checked by counting the number of spots.

NB: If the mains supply has a frequency of 50Hz, therefore 0.1sec exposure should produce 5 spots.

If the mains supply has a frequency of 100Hz, therefore 0.1sec should produce 10 spots and so on.

Spinning top image of a single pulsed unit using a 60Hz mains supply

A 0.1sec exposure produced 6 spots for a single pulsed unit using a 60Hz mains supply.

• NB: A two pulse unit will generate 12 spots in 1 second.

ACTION

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