Return on Investment Costs vs. Benefits: Comparing 64-Slice to 256-, 320-Slice CT

ROI for a 320-slice system is easier with regard to high-volume centers to absorb. “It is very costly, but our emergency division (ED) is very busy,” Poon described. Each CT scanner in the Erectile dysfunction handles between 50 in order to 60 cases per day, therefore there is no shortage of individuals to help carry the cost load.

The University of Chi town Medical Center located its 256-slice scanning device next to the emergency department. It's also used by several specialties along with cardiology. Vannier said this spreads the machine’s cost and ensures it doesn't sit idle. The 256-slice program scans much faster than 64-slice methods, so patient throughput is quicker, meaning more patients are visible in a day, he said.

There are other set costs beyond the scanner which facilities need to think about, Vannier additional. These include the cost of personnel to operate the machine and the room in which the CT equipment is located. He also said the cardiac CT program needs to be a whole package, not just a machine. A good efficiently run CT system requires a good internal scheduling program, a clear scheduling contact with individuals, a process to get authorization in the payers and ways to relax and preparation the patient for the study. Great post-processing software also is needed, as well as remote and home entry is a big plus for effectiveness, Vannier said

Four CT Scanner Generations

From historical perspective, four scanner generations are known in CT. Head scanners, which the patient by translation and rotation of the measurement system with pencil beam(a) or a small fan beam(b) and fan beam system. The “3^rd Generation” featuring a rotating detector(c)has clearly outdistance the “4^th generation” ,which utilizes stationary detector rings(d)

 Most commercial translation scanner offered a field of measurement for head examinations only. The first attempt to scan typical body cross sections by CT was also based on translation rotation principle. The ACTA scanner (automatic Computerized Axial Scanner) sampled a field of measurement with 48 cm diameter in a six minutes scans taken during a single brathhold. The instruction of fan beam scanning was the solution to this problem.

Instead of sampling a transmission profile, i.e a projection , by pencil beam with translator motion, a fan beam and a larger detector are were used to measure a complete projection simultaneously. In this approach, the available x ray power is utilized much more efficiently. The translator motion becomes obsolete and the system only executes a rotatory motion. The first whole body scanner with fan beam system came to market

 In 1976 and with this envisaged goal of 20 second per image scan time was achieved. In the first scanners of this type both the x ray tube and the detector rotated around the patient demanding  higher technical efforts but offering advantages with respect a component cost and image quality and image quality (3^rd generation). Only a little later scanner followed with a ring like stationary detector fully encircling the patient, so that only the x ray tube rotated (fourth generation). Only a little later scanner followed with a ring like stationary detector fully encircling the patient, so that quickly accepted, and translation rotation systems meanwhile disappeared almost type is over, both with respect to numbers installed and more importantly, with respect to development of multi row detectors, which will be discussed below, the third generation has prevailed

Spacial Resolution vs. Pieces Comparing 64-Slice to 256-, 320-Slice CT

www.dicardiology.com. When New York Presbyterian Medical center recently decided to give a new scanner because of its dedicated cardiac CT laboratory, the ability to increase spacial quality was the determining factor over quantity coverage. “We had the choice to go with any scanning device, but what we are curious about is increased spacial quality,” Min said. “But, We don’t want spacial resolution at the expense of higher radiation dosage.”

The hospital purchased a General electric Healthcare LightSpeed CT750 High Definition (High definition) 64-slice CT system. The scanning device is supposed to produce pictures 100 times quicker than standard 64-slice methods, with up to 47 % greater image fine detail in the heart. The machine uses GE’s Gemstone technologies with adaptive record iterative reconstruction (ASIR), to provide improved spatial resolution which reduces calcium blossoming artifacts. ASIR also offers as much as 50 percent less rays dose without diminishing diagnostic image high quality.

Many of Min’s patients tend to be older and have a large amount of calcium or numerous stents; traditional CT has had problems penetrating them with regard to clear images.

“We are now able to see through calcium as well as stents better than with the more mature 64-slice systems,” he said. The brand new CT system’s resolution also enhances luminal diameter visualization for any more accurate diagnosis.

“It enhanced our diagnostic guarantee and eliminated the requirement for additional tests,” Minutes said. This assisted reduce the number of individuals referred for additional screening, which helped spend less and the amount of time required to assess a patient’s situation.

New image renovation algorithms also reduce noise, while permitting a lower radiation dosage, Min said.

Aquillion RXL 32 Slice CT Scan Review, Specs and Price

In CT Examination, a series of equally spaced images is acquired sequentially through a specific region, e.g the abdomen or head. There is a short pause after each section in order to advance patient table to next preset position. The section thickness and overlap/intersection gap are selected at outset. Using Toshiba's coneXact™ reconstruction formula the Aquilion RXL is able to produce 32 unique pieces per rotation with increased detail than ever before. The “Double Slice Technology” allows 32 images to be generated in one rotation without dose penalties. The acquired volume information can be reconstructed at dual density, resulting in sharper pictures and provides vastly superior MPR as well as 3D reconstructions.  Showcasing the high-performance MegaCool™ X-ray tube as well as advanced Quantum sensor, Aquilion RXL enables fast helical checking of the entire body. In addition, the Aquillion RXL 32 Slice CT Scan is the newest addition to the Aquilion family with key functions such as ”Adaptive Iterative Dosage Reduction 3D” (AIDR 3D), a good iterative reconstruction formula which has been designed to additional reduce dose whilst preserving excellent picture quality.
The Aquilion RXL provides maximum performance with regard to customers needing to execute a wide variety of routine medical examinations in a sleek workflow, with the objective to provide the best diagnostic high quality at a minimal quantity of radiation. Provides the industry’s greatest low-contrast resolution of 2 millimeters @ 0.3% along with low exposure dosage. Incorporating Quantum Sensor technology and state-of-the-art dosage reduction technologies.

Estimation Price of Aquillion RXL 32 Slice CT Scan 

Used : 900000 to 1.2 million $ in USA

Lightning Speed of Aquillion RXL 32 Slice CT Scan
The Aquillion RXL 32 Slice CT with new console enables substantial improvements in work-flow, with faster renovation, automated processing,as well as remote access abilities. With a reconstruction speed of up to 28* images per second (16 images per second for standard configuration), all the images are available in a flash, even when Toshiba’s unique 0.5 mm slice thickness is used. Furthermore, the enhanced DICOM protocol allows fast data transfer speed up to 60 images per second. Generation of MPR images can be performed automatically in accordance with the exam protocol setting.

• High-Speed Reconstruction
• Automated Processing
• SUREXtension™ (Remote Access)*

Latest Applications option

• Cardiac Examinations*
• Colon View*
• Lung Volume Analysis*
• Vessel View*
• Fat Index View* and more..

Imaging sample result

CT Scanner Technologies Highlighted at SCCT

Since the kVP rise and fall are incorporated into view measurement , a fast switching generator is required, and any reaming low level non idealities are accounted for in the spectral calibration of the data. In order to combat the traditional flux issues that have challenged fast kV switching , low kVp and high kVp acquisitions are flux balanced through advances in the DAS, which allow for dynamically changing view integration times. Additional time allocated to low kVp acquisition relative to the high kV acquisition in oreder to reduce photon starvation conditions. Coupled with the appropriate rotation speed , amore balanced flux condition between the two kVp scans is achieved and serves to minimize patient dose. Fast kV switching scans have designed to minimize the additional dose relative to single energy scans, In a recent dose and low contrast detectability (LCD) comparison(Li et al, 2010), the effectiveness of this sampling scheme with respect to dose was demonstrated by matching the LCD at as a slice thickness equal to 5 mm and object of 3 mm.

The Aquilion Perfect system has an 80-slice sensor, but can be improved in the field to some 180-slice system.Computed tomography (CT) suppliers highlighted several current improvements to their image resolution systems during the Next year Society of Cardio CT (SCCT) annual scientific conference in July within Baltimore, Md. 

GE outlined its Discovery CT750 High definition FREEdom scanner, that provides a new type of sensor for better signal-to-noise percentages and new renovation software to reduce sewing artifacts and sound of low-dose scans. Additionally, it offers the ability to carry out dual energy tests using a single X-ray pipe modulated every 0.Five milliseconds between 80 as well as 140 kVp.

The system’s Independence (Fast Registered Powers and ECG) software provides intelligent motion modification via SnapShot Deep freeze, enhanced coronary visualization even just in the presence of calcium, comprehensive plaque material make up assessment and correct perfusion calculations. SnapShot Deep freeze is supposed to significantly decrease coronary motion and conquer the limitation of hardware-only solutions. It specifically detects vessel movement and velocity as well as determines actual charter boat position and can make corrections.

“SnapShot Freeze is a game changer by increasing the effective temporal quality, and from the preliminary images, I see considerably reduced motion items and significantly enhanced image clarity,” stated James Min, overseer of cardiac image resolution research and co-director associated with cardiac imaging from Cedars Sinai Hospital and present president of SCCT. He's a principal detective for the VICTORY test, which is evaluating the actual diagnostic accuracy associated with SnapShot Freeze movement and stitching madame alexander doll correction.

Toshiba’s newest CT product is the Aquilion Prime, the replacement for its prior 64-slice system. It is an 80-slice program that can be upgraded within the field over a weekend break to a 180-slice system. It provides a 78 millimeters bore and has 660-pound capability tables to accommodate bigger patients.

Earlier this year, Siemens launched the new Stellar sensor for its CT systems, which utilizes integrated, printed microcircuits rather than soldered circuit boards. This particular reduces the amount of digital noise in tests by about 20 %. The new detectors additionally overall improve picture quality by reducing calcium supplement and metal blossoming, so it is easier to assess in-stent restenosis.Noise suppression is automatically Applied to GSI imaging and is used on the material density images in order to enhance the quality of the image without shifting the mean values. This allows for a quantities material density image with good image quality. The noises suppression it self leverages the statistical iterative reconstruction approach taken by ASIR(fan et al,2010).

Filter Component of CT System

The x ray photons emitted from the x ray tube exhibit wide spectrum;many soft (low energy) x rays are present. The low energy x rays mostly absorbed by the patient and contribute little to the detected signal. There fore, it sis necessary to remove these soft x ray to reduce the dose to the patient. To achieve this objective, most CT manufacture employ additional x ray filtration to improve the quality of the beam. The most commonly used filters are the flat filter and the bowtie filter. The flat filter is typically made of copper or aluminum, and is placed between the x ray source and the patient. The flat filter modifies the x ray spectrum uniformly across the entire field of view. Observing the fact the the cross-section of a patient is mostly oval shaped, some manufactures employ a bowie filter to modify the intensity of the x ray beam inside the field of view to further reduce dose to patient. 

To achieve this objective, most CT manufacturers employ additional x ray filtration to improve the quality of the beam. The most commonly used filter is the flat filter and the bowtie filter. The flat filter is typically made of copper or aluminum and is placed between the x ray source and the patient. The flat filter modifies the x ray spectrum uniformly across he entire field of view. Observing the fact that cross section of the patient is mostly oval shaped, some manufactures employ filter to modify the intensity of the x ray beam inside the field of view to further reduce dose the patient.

 

Toshiba Aquilion™ CXL–series Reviews, Specs and Price

Nevertheless, the relevant quantity for risk assessment is the effective dose, which takes not only the organ doses into account but also the relative radiation susceptibility of the various organs and tissues within scanned body region. Aquilion CXL is a Toshiba helical CT technique with a 64-row detector along with presents the latest state of technological innovation inside Multi Slice CT technological innovation. Using AIDR 3D, adaptive iterative dose reduction technology, for ultra low dose and full isotropic imaging through Toshiba’s unique 0.5mm detector technology. With the new coneXact algorithm the Aquilion CXL is able to generate 128 unique slices every rotation with more fine detail than ever before. The well-equipped CXL scanner provides the industry’s best low-contrast quality of 2 mm At 0.3% and incorporates the latest tools pertaining to scanning with "Low Dose" and with "Lightning Speed"! Featuring the high-performance MegaCool™ X-ray tv and the advanced Quantum detector, Aquilion CXL enables quick helical scanning of the human body.
Designed for outstanding functionality the new Aquilion CXL comes regular with highest performance allowing clinicians to boost their clinical benefits with fewer assets in less time with a smaller amount patient dose. Numerous exclusive, ergonomic functions increase patient ease and comfort and operator convenience while making treatments safer and more successful.

Aquilion CXL 64-Slice Configuration and 128-Slice Configuration type that give the Best in class low contrast resolution combined with double slice technology for superior imaging of small structures e.g. Internal Auditory Canal.

The new console enables significant improvements in workflow with faster reconstruction speed, greater flexibility with remote access, and improved efficiency through SURETechnologies software*.

• New Console Architecture, Single or Dual* 
• New reconstruction board for ultrafast image reconstruction
• SUREXtensionTM (Remote Access)
• 0.5 mm x 64 Quantum Detector
• phaseXact (Automated Optimal Cardiac Phase Reconstruction)*
• Automated Bone Removal

Price

$ 1.5 million to 2.5 million in USA

Imaging Sample Aquilion CXL 64-Slice

Provides fast and easy assessment of calcium based on non-contrasted, ECG-gated data directly from the actual Aquilion console.Calculates Los angeles scores using the Agaston technique and the Volume muscle size method A report along with the representative images showing calcium will be automatically generated

Artifacts in ultrasound

The occurrence of artifacts should be understood that sonographer / sonologist can minimize diagnostic interpretation errors that may occur. Some of the artifacts that often occur on ultrasound examination are:
1. Good group of artefacts
a. Acoustic shadow (acoustic shadow), a reduction in the intensity of the echo in the back of the masses, due to strong attenuation in the upper network
 

Figure 1. Acoustic shadow
Source: Ultrasound in Emergency Care, Adam Brooks

b. Enhancement, the sound waves passing through the liquid does not have a strong attenuation, so it looks lighter fluid below.

 

Figure 2. Enhancement
Source: Ultrasound in Emergency Care, Adam Brooks

c. Comet tail. Image looks like a comet's tail has ang caused by multipath reflections

Figure 3. Comet Tail
Source: Ultrasound in Emergency Care, Adam Brooks

2 . The bad artifacts
a. Multiple Reflection (reverberasi), occurs due to the reflection of a barrage of two layers (or more) of each adjacent reflector.

Figure 4. Reverberation artifacts
Sources: Lecture Materials D4, Artefak

b. Multipath reflection, an artifact that arises from repeated reflection of the ultrasound beam in different directions before returning to the transducer, giving rise to mirror image

Figure 5. Mirror image
Source: Ultrasound in Emergency Care, Adam Brooks

 

Figure 6. multipath reflection artifact
1. Boundary line between liver and diaphragm
2. The line between the diaphragm and lungs
3. Line of mirror image artefact
D = muscular diaphragm
Source: Collection of files lectures, Artefak

c. Anisotropic reflector, is a hyperechoic image artifacts caused, if the ultrasound beam perpendicular from the transducer, and hypoechoic when the beam ultrasonic oblique.

d.Beam artifacts, is an artifact that occurs when the object is smaller than the width of the emission ultrasound.Sehingga image depicted is a combination of object and surrounding tissue.

e.Side Grating Lobe and Lobe
Side Lobe, and Grating lobes appear in the form of additional echoes at the edge of a strong reflector.This occurs because of the additional ultra-sound emitted by the transducer in addition to the sound file
 

Figure 7. Side lobe artifacts. In the picture there is a duplication of the right azygos vein, normally in the picture
nothing left.

3. Group of ugly artifacts

• Motion artifacts, this happens to wear color doppler which sector or mechanical Annular Array probes.Because the transducer is driven by the motor so that it can cause a doppler frequency deviation of the actual velocity of blood flow.
• .Elektrical Noise / Artifacts Cross Talk, is an artifact caused by electrical interference and cross talk within the system. It is more easily detected and treated with a good grounding system.

(by: Mrs.Any  Maryani, S.ST)

B-flowmode on Doppler Ultrasound

The B-flowmode is not a Doppler technique based on the processing of the Doppler shift but a B-mode scanning technique that compares gray-scale scans over time to identify changes in the spatial positions of reflectors (blood cells) by the successive emission of coded pulse packets. The echo signals are subtracted from one another, and the brightness is determined by the number of reflectors and partly also by their velocity. The conventional B-scan generated from the stationary echoes is display around the flow information. Since the successive pulses are emitted at defined intervals and in digitally encoded form, it is possible to eliminate interfering echoes and use only the encoded echoes in the subtraction procedure. Hence, only the amplitude signal reflected by moving particles is processed in the interval between two pulses. As the signal strength increases not only with the number of reflecting particles (volume flow) but also with flow velocity, a jet within a stenosis is depicted with a higher signal intensity. The advantage of this technique lies in the simultaneous display in a single image of hemodynamic parameters (comparable to angiography) and morphologic details of the vessel wall with a high resolution while showing no or only little angle dependence. Disadvantages of B-flow imaging are the occurrence of artifacts in highly pulsatile, atherosclerotic vessels, the susceptibility to artifacts caused by wall motion, and the still limited scanning depth. With further technical advancement, B-flow imaging will, in principle, enable morphologic quantification of stenoses and differentiation of the vessel wall from the patent lumen even if only slow flow is present (e.g. in ulceration). The B-mode provides a high-resolution display of the vessel wall contour with separate representation of blood flow in the B-flow mode. There is no superimposition of blood flow information as in color duplex scanning.

Stress Testing on CT & Changes in Reading Images Comparing 64-Slice to 256-, 320-Slice CT

Stress Testing upon CT

Min said the actual higher-slice systems may present an advantage in perfusion image resolution compared with 64-slice, because of their capability to image the entire coronary heart at once. Up until now, he explained only 64-slice systems happen to be evaluated for CT perfusion image resolution. The higher-slice systems will probably show CT can be used for high-quality heart perfusion imaging, but studies are needed. These systems also provide additional perfusion applications with regard to liver and mind imaging. This may assist justify the higher price, if shared in between several specialities.

The actual Aquilion One 320-slice scanner may complete an entire physique scan in 3 seconds and a coronary heart scan without desk movement in less than fifty percent a second. Poon said this particular speed and protection will allow CT adenosine stress image resolution, which is primarily restricted to magnetic resonance imaging (MRI) as well as nuclear imaging.

“Nuclear continues to be the standard of treatment (for perfusion imaging), however the temporal spatial resolution isn't good at all,” Poon stated. He added the reduced resolution can skip small perfusion defects which are easily seen around the 320-slice images.

Changes in Studying Images

The minor misalignments in 64-slice cardiac pictures lead to many items, which radiologists and cardiologists consider when reading. Nevertheless, a 320-slice scanner picture eliminates such items. Poon said what you see may be the actual, full coronary heart frozen at a particular time.

“I had to alter my reading routines,” Poon said. “I was so accustomed to reading 64-slice that I simply assumed many things We saw were items. But now what I 'm seeing is a sore; it’s not an artifact anymore. You have to look at the 330 under a different mild. You can’t assume you will find artifacts anymore.”

The actual University of Chi town Medical Center uses 16-, 64- as well as 256-slice systems. Some individuals had exams carried out at different occasions by two or even all three of the methods. Vannier said the radiologists in comparison these images as well as were able to pick out the actual 256-slice system immediately. Just about all motion was freezing and the images didn't have the “blocky” misaligned sewing artifacts, he said. Our prime motion area close to the diaphragm also contributed to movement blur that made an appearance as a thickening of cells, which would have resulted in an improper prognosis. “We started asking ourself if we were phoning things abnormal once they were actually Okay. It was really sobering,” Vannier stated.