Fluoroscopy or CT-scan?
The advantage of fluoroscopy over CT-scan is not obvious to the layman. Yet it is the imagery of choice for the treatment of pain in the vast majority of centers.
Benefits
Fluoroscopy:
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Real-time examination (i.e. if you move the needle, the image moves at the same time on the screen)
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Viewing the entire needle
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Visualization of an entire volume
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High spatial resolution (1536x1536 sensor for 30 cm x 30 cm)
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Low dose of irradiation
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Easy to clean and integrate into a "sterile" operating room type environment
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Dedicated use most often
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Procedure performed by a pain treatment specialist (SSIPM)
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Reasonable cost of the device
CT-scan:
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Easier to recognize certain anatomical structures (especially in the section plane)
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Better visualization of non-bony structure (such as disc or root)
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Possibility of reconstruction in multiple planes (at the cost of an acquisition with many cuts)
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Dose of radiation received by the doctor and the team reduced (advantage of not being in real time)
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Profitability of equipment that is often underused (due to the superiority of MRI over CT-scan for many indications)
Disadvantages
Fluoroscopy:
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Difficulty recognizing certain structures if the fluoroscopy angles are incorrectly chosen
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Invisible non-bony structures (disc, nerve, etc.) and their position is determined in relation to bone landmarks (requires a better knowledge of local anatomy)
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Dose of radiation received by the doctor higher because the fluoroscopy is done in real time
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No reconstruction in other plans on conventional devices
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You have to understand geometry to use images properly
CT-scan:
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Deferred time examination (that is to say, we move the needle blindly, then we make cuts to locate it)
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Partial visualization of the needle always leaving some uncertainty about the position of its tip
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Viewing one cut at a time
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The needle is never completely in the cutting plane
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Metallic needle artifact interfering with visualization
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Low spatial resolution (sensor of 1024 for 30 cm) with a slice thickness of about 3 mm ( thinner slices up to 0.6 mm are possible but increase noise ). Subjectively excellent image quality is achieved by mathematical smoothing, not true resolution.
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High dose of irradiation
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Difficult to clean and integrate in a "sterile" operating room type environment
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Shared use (with the risk of bringing resistant germs with patients with multiple diseases)
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Procedure performed by a radiologist (rarely a specialist in SSIPM pain treatment)
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You have to understand mathematics and computer science to use images properly
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High cost of the device