EBME Forums Forums Free discussion Free discussion why not repair rx tubes? Inserts

Determining the location of that image would be a bit of fun, perhaps for the non-work related site.
I can think of a few deductions:
1) from the corrosion on the antennas: saline or very humid environment, perhaps close to the sea
2) from the angle of the solar collectors (few) close to the equator, or at least above the tropics.
3) Obviously warm (many parasols)
4) densely populated
5) buildings of similar height (builders' decision not to be exposed to the winds? typhoon zone? Monsoons?
I rule out America and Africa; I'll risk India or Southeast Asia

Old tubes aside, what technologies are you using on the CR (or DR) side of things?

As you know, in general terms x-ray bean quality is determined by kVp ... and (in theory at least) a degraded tube should still be useful (up to a point) with modern image receptors and DI (etc.) software. In other words, modern systems can produce quality radiographic images almost regardless of how clumsy the radiographer (that is, less than optimal factors being set at the control panel). That's the beauty of the modern digital system.

However, I recall that various manufacturers came up with their own approaches to Exposure Indexing. I am hoping that by now IEC 62494 has introduced some badly needed standardisation and conformity.

Meanwhile, medDream looks interesting. I include the link as a point of reference; and it also contains a fair amount of (hopefully relevant) information.

Old tubes aside, what technologies are you using on the CR (or DR) side of things?[/quote]

CR in most cases. I have my reservations about DR technology. They are expensive, at least in this part of the world; suffer from the deterioration of delicate electronics and are sensitive to rough treatment. Finally, they only pay for themselves with high usage rates, which is not our case.

Meanwhile, medDream looks interesting. I include the link as a point of reference; and it also contains a fair amount of (hopefully relevant) information.[/quote]

Interesting, thank you very much for the information, for the moment we use the integrated viewer (WEASIS)

Yes; I should imagine there are still thousands of screen-film radiography (SFR) systems around the world (not to mention old-school radiographers) that continue to produce perfectly adequate images of diagnostic quality.

CR (and DR) set-ups can also lead to "poor" practices too ... sloppy collimation, for example, and over-exposure(s) due to "dose creep"; both resulting in higher doses to the patient.

However, most of the stuff I have seen these days seems to assume an "onward march" ... SFR->CR->DR. There is probably a nice career to be made there in "project managing" all those system upgrades (or evolutions).

You point about cost is also a good one. In the various articles and papers I have seen excitedly espousing the virtues and advantages of "digital radiography" (and there are indeed many) I have hardly ever seen "cost" being mentioned (and certainly no valid cost-benefit analysis).

Anyway, back to tubes. What do you reckon about the feasibility of prolonging the usefulness of old (deteriorating) x-ray tubes by employing the "magic" (digital processing) of CR? Perhaps you have already done (or are now doing) this?

WEASIS looks interesting (I had not come across it before).

Totally agree, see this:
“Because of the automatic adjustment of grayscale in digital imaging, until the limit of adjustment is reached, overexposed images have a more pleasing appearance than underexposed images. Technologists respond to feedback from radiologists who naturally prefer less noisy images. Thus, receptor exposures tend to increase over time, and consequently, patient exposures also increase”
From: “One Year’s Results from a Server-Based System for Performing Reject
Analysis and Exposure Analysis in Computed Radiography” Journal of digital Radiography 2009
A. Kyle Jones,1 Raimund Polman,1 Charles E. Willis,1 and S. Jeff Shepard1

There are some analyses, but unfortunately they can go against the grain, at least in some market approaches.

In the accompanying figure (I take the image from cep 07011) imagine the functional costs in services that serve between 5 and 10 studies per day.

Regarding mammographic studies, the CEP 08015I report is very good, a cost calculator for mammography that includes the NHS reference values.

Taking into account that CR systems allow a local calibration (Shading calibration) applying a theoretical dose of 20uG.
If we intervene in conjunction with a non-invasive meter of radiographic values ??we can adjust the final image result of the CR for an adequate quality, discarding the metallization and aging of the tube that degrade performance. This allows us to make a relative adjustment to the site (Hermanar CR with RX emitter). The meter we use has an ionization chamber so there is an extra supervision of the 20uG value.