Equipamentos radiológicos veterinários: CR x DR

The final quality of a radiographic image depends on several factors: the equipment available, the choice of technique used, the patient's positioning under the X-ray beam, and the method of developing or transmitting the acquired image. Regardless of the chosen method for image processing, common to all modalities, whether using conventional films, computed radiography (CR), or digital radiography (DR), is the existence of an X-ray radiation source. This can be fixed, mobile, or portable. Typically, the first is more powerful and operates at a higher milliamperage. Milliamperage is one of the technical factors adjusted for radiographic exposure and is related to the contrast obtained. In acquiring images using radiographic films, a plastic film impregnated with silver salts and housed within a cassette (chassis) is exposed to radiation. Chemicals are necessary for the development process, and the final result is exposed and fixed on this radiographic film. In CR (Computed Radiography), an image plate (IP), similarly housed in a cassette, receives the X-ray radiation emitted by the source. In simplified terms, this IP stores information that is "read" by a scanner and interpreted by the computer system. The image is displayed on the monitor and can be manipulated after acquisition (adjustments to contrast and brightness, for example). The IP is then "cleaned" and reused for new exposures. In DR (Digital Radiography), a series of radiation-sensitive elements make up the image plate to be exposed. There is no film or IP, eliminating the need for development or scanning. Once the plate is sensitized by X-rays, the information is transmitted via cable or wirelessly to the computer, which immediately displays the result on the monitor. Conventional radiographic films are more sensitive to radiation than image plates in CR equipment. DR equipment plates, in turn, are more sensitive to radiographic exposure than these other two types of acquisition. Therefore, to acquire good images with a CR plate, a higher milliamperage is necessary compared to film or DR equipment, which is usually achieved with fixed emitters. The use of techniques with higher milliamperage, as well as kilovoltage, is mainly associated with the patient's size. Techniques with low milliamperage, using CR plates as a means of acquisition, tend to produce grainy, less contrasted, or even less sharp images (in this case due to the exposure time, associated with the milliamperage in some equipment) when the patient to be radiographed is larger and/or has a higher body score. In summary, the use of CR equipment with a low milliamperage source can, in specific cases, generate artifacts in the image and consequently limit diagnostic interpretation, especially when dealing with large patients or the region to be evaluated. However, it is important to clarify that combining portable sources with CR equipment can provide excellent images, provided that the technique used is adapted to the characteristics of the patient undergoing radiographic examination. Therefore, knowledge of the available equipment is necessary so that the choice of configuration to be acquired and used allows for the best final result, meeting the needs of the service and, above all, benefiting the patient with the best diagnostic outcome. --- This is the YouTube channel ‘imagem.vet – Veterinary Teleradiology’. Pioneers in veterinary teleradiology in Brazil, we aim to help promote animal health by disseminating high-quality, ethical, transparent, and agile diagnoses, breaking down the physical barrier of distance using up-to-date digital and technological tools. YouTube becomes our way of freely sharing everything we know so that the quality of life of our little companions helps improve the quality of life of ourselves. www.imagem.vet New videos every month. Creative direction of the channel: Ari Hollaender   / hollaender   Song: Driving Space, Black Hole version, by Michael Lorello