CT scanners serve to implant internal body structures. They provide detailed anatomical information based on the principle that different types of histological structures are displayed in the image as different gray shades. Intravenous or oral contrast media can be used to further intensify differentiation between tissues
The core components of the CT scanner are a curved banana of an x-ray tube and a detector or a flat panel with a circular aperture. The patient's long axis (Z) has a number of such detector arcs, resulting in the multiple-slice CT expression.
Multi-detector CT is also commonly used. Depending on the CT scanner model, the detection rows range from 12 to 160 mm.
CT scanner technology has evolved in the past few years for more efficient, more stable sensors, more sophisticated engineering and technology solutions for data collection systems and electronics as well as faster computers
These CT scanners developed largely to scan longer lengths of a patient, slices. As a result, CT scanners were formed from a slice-slice diagnostic imaging system as a truly volume imaging method where images can be reconstructed in any plane without losing image quality. This led to increased use of multi-plane and 3D display modes during diagnosis.
However, it is important to note that the performance of CT scanners in practice depends on the compromise between image quality and exposure. As a result, each system should be evaluated for clinical performance, taking into account the radiation dose used.
Generally, multiple scratch scanners cover the patient's volume in rotation between 20 and 40 mm. The most recent diagnostic multi-slotted CT scanners can represent up to 160 mm patient batches per batch
The length of the detector array of CT scanners determines the number of rotations needed to calculate the total scan length, and consequently all scanning time. The one-time, less rotation test allows you to minimize headaches in the X-ray tube to allow longer scanning.
The CT scanners detector blocks are divided into two types: fixed and variable. Fixed arrays have equal z-axis size detectors in the entire array array while the variable arrays; the central part contains finer detectors. For variable arrays, the full scan time for the given length is longer because the z-axis coverage is reduced.
CT Scanners with Larger Transmission 64 Contains Fixed Blocks
Full The organs coverage is beneficial for both dynamic perfusion and heart rate testing. The z-axis sensor for the current 64-slice scanners is up to 40 mm long enough to cover these organs with only a few rotations. The length of 160 mm coverage generally allows full organic coverage with a rotation, so the entire body function can be controlled over time.
The development of CT scanners reflects different strategies to accommodate future developments and allows production costs. There are also some small savings that use larger sensor elements for lower-slice category scanners
Spatial resolution is the ability of CT scanners to form an object without blur. Often the sharpness of the image is described. It is possible to distinguish the shortest object size and evaluate it as such using high contrast test objects where the signal noise level is high and does not affect perception.
Modern CT scanners should be able to reach isotropic resolution: the z-axis resolution that is the same or close to the test plane as this is essential for high-quality, multilevel and 3D reconstructions.
It is useful to note that high spatial resolution of CT scanners in high visual noise or high patient radiation dose when tube current is increased to reduce image noise
Contrast resolution of CT scanners is the ability of CT scanners similar. Sometimes it is also referred to as low contrast detectability. The ability to detect an object depends on the contrast, the size and size of the image noise. Contrast resolution is usually determined by the minimum size of a given contrast difference object that can be solved for a specific scanning set
The time resolution of CT scanners is the time that a temporal resolution is usually associated with heart test in CT scanners. The CT of the heart is designed to minimize image information thanks to the movement of the heart. This can be achieved by using ECG gating techniques and the heart can be mapped during the minimum heart rate movement that results in very short time-to-resolution resolution of the heart rate
The optimum combination is the number of panes and the number of each spin speed.
CT Scanner Detectors captures the patient's beam and transforms it into electrical signals that are later converted to binary coding for a further computerized processing system
CT Scanners Detectors must be able to respond to a signal at an extreme speed without delay, they must quickly discard the signal and prepare for the next one. They must be small and demanding too. CT scanners detectors have high capture efficiency, high absorption efficiency and high conversion efficiency. These three parameters are known as detector efficiency
capture efficiency is how well the detectors are able to detect the patient's photons. Determined primarily by sensor size and distance between sensors
Absorption efficiency is the ability of sensors to convert incoming x-rays. This is mainly determined by the materials used and the size and thickness of the sensor.
Determines conversion efficiency by how the sensor converts absorbed photon data to CT scanners manufactured by the computer's digital signal
the entire set of sensors consists of groups of sensors, each of which is known as a detector module, connected to the system board.
Flat sensors have been developed for radiography and fluoroscopy aimed at replacing standard X-ray film, film filter systems and image sensors with a state-of-the-art solid-state sensor system. Flat sensor technology offers high dynamic range, dose reduction and fast digital conversion – yet with a compact design. It seems logical to apply the same design to them.
The use of flat panel detectors for CT scanners is a very effective way of detecting x-ray radiation and acoustics. Flat sensors provide great spatial resolution. However, there are also disadvantages: relatively lower dosage efficiency, smaller areas or views, and lower temporal resolution
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