Hi,
I am a radiographer so might be able to offer some advice.
The gantry system will have one major technical advantage - Higher heat capacity
A low heat capacity ultimately will limit the amount of radiation that can be delivered per second during exposure which theoretically could mean that the signal to noise ratio for obese patients might be poorer or the exposure time longer and therefore the images exhibit graininess and/or motion blur.
All other advantages will be operational including: The gantry is already on site, so less setup time? Does not clutter up and obstruct the patient during examination?
Disadvantages include loss of service if it breaks down, it can't easily be replaced/repaired without disruption whereas a mobile can be swapped and serviced away from the department. Unless the funding is generous, it is unlikely to utilise the most modern flat panel detectors, as it will not be used frequently enough to justify the cost.
There are some swanky expensive technologies that could be incorporated into the gantry machines, such as digital tomosynthesis and energy subtraction - but these are likely to be too fiddly for routine use in resus when the pressure is on (despite giving some stunning image quality gains see these: http://www.youtube.com/watch?v=dIxARb70ssA&feature=mfu_in_order&list=UL and http://www.youtube.com/watch?v=J8RnM3eg8mU )
The 'digital' mobile that the radiology manager has suggested is a good solution for basic radiography because the reduction in heat capacity reduces cost for the x-ray generation technology, and therefore the flat panel detector becomes cost effective. The mobile will be able to serve the entire A&E department including cubicles - so its cost is defrayed against a much higher usage.
Another reason the radiographers will prefer the flat panel detector is the fact that it can provide instant (7 seconds) review images. These can be used to alter setup and retake to gain a higher quality image without delay. It might engender higher radiation doses if this is done too frequently, and therefore this must be subject to audit. Another risk to guard against is that the images produced for review will be used for quick diagnosis. The image quality is NOT DIAGNOSTIC and a protocol will need to be drawn up to transfer these quickly to a local PACS workstation for DIAGNOSIS.
Regards
Phil
Philip Cosson, MAS, MBIR, MSR, RHPC
Diagnostic Radiographer
Short C.V. http://myprofile.cos.com/philipcosson
Philip Cosson | Senior Lecturer | Room H1.19, Centuria Building | M: +44 (0)7817 362823 | www.tees.ac.uk
University Open Day: 22 June 2011, 10.00am - 3.00pm - view event details
Middlesbrough, Tees Valley
TS1 3BA UK
T: +44 (0)1642 384175
F: +44 (0)1642 384105
Click Here for campus map
-----Original Message-----
From: Accident and Emergency Academic List [mailto:[log in to unmask]] On Behalf Of Jason Carty
Sent: 16 June 2011 10:06
To: [log in to unmask]
Subject: Gantry vs Mobile
Dear all,
Currently we are in the process of putting together a procurement list for a new ED. The originals plans/provisions were for an x-ray gantry in resus but our radiography service manager would rather have a digital mobile machine. The radiology argument is that a mobile machine would be easier to use and offer a greater scope of x-rays that could be done as portables. I'm not a radiographer so I find it hard to find a reason to prefer the gantry option beyond the aesthetic appearance of the machine.
Has anybody else on the list had this debate about gantry v portable?
Regards
Jason Carty
EM Consultant,
Kerry General Hospital, Tralee, Co.Kerry
|