- The benefits of more slices (6 vs 64)
In this comparison we compare the performance of two systems.
One has 6 slices (like an Emotion 6), the other has 64 slices (like a Sensation 64). However, since the increase in performance in terms of slices is almost linear other devices may also be considered.
Of course slice thickness and rotation times also play a role. To keep the comparison as simple as possible we assume a slices thickness of 1mm and a rotation time of 1sec. per full rotation.
Image quality is one of the most important, if not the most important factor to be considered because only with good image quality a doubtless diagnose can be made.
Although the layer thickness plays a greater role here a larger number of lines also allows a larger image. Thus entire organs are assembled from fewer individual images. This results in an image with fewer artifacts which usually occur at the interfaces between two images. Especially with moving organs like the heart this makes a big difference.
The scan time is reduced linearly with the number of slices. This means a 6-slice-scan takes 10.66 times as long for the same task as a 64-slice-scan.
An area of 30cm is to be scanned.
The 6-slice-scanner covers 0.6mm per second and thus takes 50 seconds.
The 64-slice-scanner covers 6.4mm per second and therefore only needs about 4.7 seconds.
Therefore in facilities with a high volume of patients high slice CT systems are a clear advantage as a lot more patients can be served in within the same time.
Although tubes for a 64-slice device are usually much more expensive to buy they are also much more profitable to use. The more slices the device has the shorter one must scan. That means that for each scan a tube accumulates less scan seconds to it‘s count which represent the generally recognized value for tube wear and come along with a high decline in value.
The operatin costs for a 30cm scan can be up to 10€. And even with smaller scans this makes a big difference after a few thousand patients.
- Save money with exchange prices
When buying spare parts you can save a lot of money, as long as you can stick to a few small rules. Besides the outright prices there is the option of exchange prices, especially for the more expensive items.
How does this work?
It’s actually quite simple: you exchange your defective part for the new one and pay the difference. And since even defective parts still have a very high material value, the price difference can be enormous.
How big are the price differences?
This can vary greatly from part to part and is therefore difficult to say, but anything from 2-18% is possible. With a brand new tube this can mean that the exchange price is 12.000€ less than the outright purchase price. This corresponds to the value of a small car.
What is important to know?
As long as the defective part was not damaged intentionally or through negligence or is destroyed beyond recognition exchange prices, if they exist for the respective part, are possible.
In addition, there is often a time limit that must be observed. These deadlines indicate the time in which the part must be sent to the supplier for the exchange price to be approved and are usually related to manufacturer specifications.
Any information about these deadlines should be obtained directly from the supplier. However, if you are given an exchange price but no deadline, it is always a good idea to ask again.
- Sensation vs Emotion
Emotion devices are significantly smaller than those of the Sensation series. It is not only the gantry itself that has smaller dimensions but space must also be created in the floor and outside the building for a Sensation CT. These additional requirements are related to the water cooling of the device which needs the right cooling hoses and an external cooling device known as a chiller.
So if space is limited an Emotion CT is the more appropriate choice.
As already mentioned Sensation CTs are cooled with a water circuit. This requires an additional cabinet which houses the pump and the heat sink (usually placed on the roof) outside the building. To keep everything connected hoses have to be laid which can be a quite complex task depending on the building.
Emotion CT, on the other hand are air-cooled and therefore do not require any additional external attachments or similar additives.
So why would you want a Sensation for the extra effort?
The big advantage of water cooling is that you can scan without a break. The cooling is so effective that the device never overheats when in working order.
An Emotion on the other hand usually needs a cooling break of 15-20 minutes after 10 consecutive scans at the latest and is therefore not suitable for facilities with a high patient volume.
Sensation devices also offer a significantly higher number of slices. You can choose between 4, 10, 16, 40 and 64 slices.
The Emotion devices offer 1, 2, 6 or 16 slices.
The top device of the Sensation series therefore has 4 times the number of slices of the top Emotion device and since more slices always bring a linear increase in performance you can scan 4 times faster with a Sensation 64 compared to an Emotion 16.
More information about slices can be found in our article “The benefit of more slices”.
The biggest price difference is always related to the slices of the device. Nevertheless Sensation CTs are usually more expensive. Both in terms of installation and maintenance.
The one exception is an Emotion 16, which can be a bit more expensive to maintain than some Sensation devices with 16 slices or less. The reason for this is the tube price.
An Emotion 16 is equipped with a Dura 422, which is more expensive than an Akron Q, which can be found in Sensation 4, 10 and some 16s.
From 40 slices up you will only find Straton tubes in Sensation CTs which cost considerably more than all other tubes.