COMPUTER SYSTEMS OPERATOR'S CONSOLE Computer Keyboard Monitor Mouse/Trackball The operator's console is the primary interface between the technologist and the scanner, and it usually includes: Nowadays, operator's consoles resemble personal computers more than specialized diagnostic equipment. Adjusting scan parameters Accessing patient information Providing post-processing instructions Filming archiving data Networking At the console, you can perform various tasks such as: The screen's visual design is known as the user interface. Systems often use graphics such as icons and folders to initiate tasks, is called the GUI OPERATOR'S CONSOLE Input device (Mouse + Keyboard) Output device (Display) Central Processing Unit (CPU) / Image Reconstruction System (IRS) Internal memory External memory The host computer is the primary link between the technologist and other CT components. It works like a regular computer, receiving commands from the operator's console and directing other components. It comprises five hardware components, which are as follows: HOST COMPUTER Patient information Imaging parameters for the scan System commands for post-processing tasks Image manipulation commands Archiving commands for storing images. Keyboards belong to the category of input devices, which are hardware components used to provide data and instructions to a computer system. The keyboard is an input device used to enter the following data: KEYBOARD Navigating the graphical user interface (GUI) Planning the scan Selecting scan parameters Displaying images Choosing post-processing options. Newer CT scanners typically include a mouse that looks like a regular PC mouse, while older models may not have had one or had it as an optional accessory. The mouse/trackball can be used for the following tasks in a CT scanner: MOUSE / TRACKBALL Graphical user interface (GUI) Feedback on commands entered by the user Various images, such as clinical or diagnostic images Network information, if the device is connected to a network. The monitor is a display device that can be used to show the following: MONITOR Displays images made up of small picture elements called pixels The arrangement of pixels forms an image matrix. Higher matrix size results in more pixels, leading to better image resolution. Brightness in the image is determined by the Hounsfield Unit (HU), which is the measure of attenuation. MONITOR CRT (Cathode ray tube) LCD (Liquid crystal display) Lower cost Compact size Low power consumption Better color representation Excellent image resolution High luminance (brightness) There are two types of monitors: LCD monitors are now commonly used in modern scanners by manufacturers. Advantages of LCD monitors: MONITOR CRT LCD 12:1 15:1 20:1. Laser camera is used to record or print CT images onto film. CT prints on 14 x 17” single emulsion film. Typical image formats: LASER CAMERA It's speed. Newer CPUs operate at GHz speeds. The amount of data it processes. The CPU is the main component of a computer that executes program instructions, arithmetic functions, and manages access to memory and peripherals. It is also the largest integrated circuit on the motherboard. CPU power is based on: CENTRAL PROCESSING UNIT (CPU) External memory refers to data stored on an external storage media. It is designed to be removable from the host computer. This makes it easy to transfer data onto another workstation. External memory includes magnetic optical discs , DVDs , e xternal hard drives , and dedicated servers like the Picture Archiving and Communications System (PACS) EXTERNAL MEMORY Managing table movement Adjusting the tilt angle of the gantry Initiating or terminating X-ray tube exposure Overseeing intercom controls The scan controller, which includes the scan control module or system console, is responsible for the following functions: This component is considered the central core of the CT scanner and plays a crucial role in both image acquisition and scanner controls. SCAN CONTROLLER Amplifying analog signals Converting them to digital signals Transmitting signals for reconstruction Digital-to-analog converter (DAC) High Voltage Generator Amplifier Sample/Hold Analog-to-digital converter (ADC). The electronics set receives patient data and performs three tasks: The DAS includes: These components collaborate to convert patient data into a digital format for image reconstruction. DATA ACQUISITION SYSTEM (DAS) DAC is the component of the interface is responsible for transforming digital numbers from the computer into analog voltages or currents. In preparation for sending instructions to the gantry and high voltage generator, the technologist's input from the scan controller must be converted from a digital format to a continuous analog signal Since the high voltage generator, gantry, X-ray tube, detectors , and patient table all rely on analog signals, this transformation process is essential for proper functioning of the CT scanner. DIGITAL-TO-ANALOG CONVERTER (DAC) It used to be a large and heavy piece of equipment, securely fastened in the CT room for safety. Modern innovations have led to the development of smaller and lighter high- voltage generators. In some modern CT scanner models, the high- voltage generator is housed within the gantry itself. The High Voltage Generator produces the voltage required for X-ray generation. The X-ray tube is supplied with high voltage via a large, bulky, high-tension cable. HIGH VOLTAGE GENERATOR Traditional high voltage generators were large and heavy. Modern generators are smaller and lighter, and can be housed inside the gantry. X-ray tube is supplied with high voltage through a bulky high-tension cable, which can be a disadvantage. In modern CT scanners, high voltage generators are safely attached to a stationary location in the CT room. High Voltage Generator generates voltage needed to produce X-rays. HIGH VOLTAGE GENERATOR The signals from the gantry are sent directly to the amplifier. The amplifier amplifies the analog signals and sends them to the sample/hold component. Amplification is done without any conversion of signals. The amplified signals are then processed and reconstructed to generate the final image. The amplifier is a component in CT scanner that receives analog signals from detectors and converts them back to digital signals. AMPLIFIER Receives amplified signal from the amplifier Samples the image Differentiates among structures imaged with various densities Assigns various shades of gray to the pixels in order to represent those structures. The Sample/Hold Component is an important circuit board located between the amplifier and the Analog-to-digital converter (ADC) in the Data Acquisition System (DAS) of a CT scanner. Its main functions and features are: SAMPLE/HOLD COMPONENT It converts the analog signal back to a digital signal. The digital signal is necessary for the data to be understood and analyzed by the host computer The data will then be sent to the array processor for reconstruction Analog-To-Digital Converter (ADC) is a circuit board that performs the opposite function of the DAC. ANALOG-TO-DIGITAL CONVERTER (ADC)