Aldo Taddei
MD
Chief of Radiology
Valdelsa Hospital
Poggibonsi (Siena) Italy
E: [email protected]
The Valdelsa Hospital is a modern institution that serves the Siena region and the surrounding territory in Tuscany, Italy, which includes a significant non-Italian population thanks to its popularity as a tourist destination. The Local Healthcare Unit, to which the Valdelsa Hospital belongs, started a significant technological renovation programme in 2005. The goals of this programme were to update existing imaging systems with state-of-the-art technology and create a digital network to connect all the hospitals within the Unit.
[[HHE06_fig1_R38]]
An integral part of the programme was the purchase of six new digital radiography (DR) systems (Italray). We were well aware of the many advantages of DR technology and were keen to see for ourselves how they would improve our workflow. The new system was installed in February 2006. The amorphous silicon (a-Si) flat-panel DR detector is mounted on a multifunctional stand that, thanks to its -20°/+90° tilting, can work in both horizontal (patient on table or gurney) and vertical (patient standing) configurations. When in horizontal configuration, the detector also rotates by 90°, aligning the grid lines with the X-ray beam direction and allowing radiologists to perform oblique projections without any grid shadow. The X-ray tube is mounted on a ceiling suspension and most stand/ suspension movements are motorised and synchronised to enhance productivity and minimise repetitive work. Many DR systems on the market require large rooms; however, thanks to its size, the new system takes up very little space and can therefore be installed also in small rooms. In addition, patient accessibility is advantageous from all sides – a very important feature in emergency and trauma applications.
[[HHE06_fig2_R38]]
Key advantages of DR technology
DR technology produces images that are stored digitally, allowing image transmission, softcopy review, postprocessing, printing and storing without any decay in original image quality. Digital images can be enhanced by working with window/level and by zooming in we can evaluate structures that would be impossible to observe with traditional techniques. Image quality is really outstanding. The flat-panel DR detector has an extremely wide acquisition dynamic range and contrast resolution, which means we can now differentiate extremely subtle morphological and attenuation/tissue differences at all dose/exposure levels present at the same time and in different areas of an image. This greatly enhances the clinical and diagnostic content of our X-ray studies. Images obtained with traditional film/screen and computed radiography do not have enough latitude, which makes it impossible to observe diverse structures, such as mediastinum and bone, on the same image. With DR, one image shows us everything we need to see, which gives us a vastly improved diagnostic capability. Also, thanks to the extremely wide dynamic range, over- and underexposure problems are totally eliminated and image retakes are things of the past.
Patient dose reduction is another key advantage – especially when dealing with children and young women. Dose reduction is achieved without any real decay in image quality and diagnostic content. This is a benefit of the flat-panel DR detector’s high detective quantum efficiency. Images are now available within seconds after exposure. This is particularly important in emergency applications, when an image-based decision has to be taken right away and there is no time to waste. Furthermore, this almost instantaneous image availability allows our technologists to perform the quality control procedure immediately and find out if the acquired image fulfils its goal. If something happened during the exposure (eg, patient movement), then the image can be retaken immediately and patient recalls are practically eliminated. Last but not least, with DR technology images are created as digital files and the burden of carrying around, developing (film/screen) and reading (computed radiography) cassettes is finally over – and this saves a lot of precious clinical time.
Workflow optimisation, system versatility
Integration of the DR system within the internal network and with our RIS was straightforward – when a patient enters the X-ray room we now have all his/her information automatically on the acquisition workstation, significantly reducing data entry errors. When the exam type has been selected, all X-ray parameters are automatically set on the generator. Appropriate preprocessing and visualisation parameters are also automatically set on the workstation and no time-consuming postprocessing is necessary. All these features greatly reduce the exam time and our productivity is now significantly improved. The correct mechanical settings (source to image receptor distance, stand and suspension configuration, and collimation) are also automatically verified for the specific exam as well as the grid type; if something is not correctly set, the system warns us, but we are free to manually adjust all parameters. The system is equipped with a number of automatic motorised movements, but we can always operate it manually if we want, which is a big improvement on other systems that are automatic only. Automatic-only systems have to be slow for safety reasons because all automatic movements could be dangerous if they were too fast.
A new PACS is also being installed in our institution, which will enable us to take full advantage of the new DR system. For example, it will be possible to automatically archive new studies on the PACS as soon as the examination is finished and the patient leaves. Furthermore, softcopy review on monitors will be our standard procedure, allowing workflow improvements (staff can diagnose seconds after the examination) and significant savings in terms of film/ chemicals consumption. Teleradiology applications will also be implemented. Aside from all the clinical advantages, the DR system has enabled us to make significant cost savings.