Mobile X-ray equipment
1. X-ray mobile and detector
Portable or mobile x-ray units are considered as mobile equipment as they are equipped with wheels that enable it to me moved to different locations with a Hospital or health care unit. These are powered by an electric motor supplied by a battery that assists the movement when the Radiographer drives the mobile unit with less effort.
Mobile x-ray systems are often used to perform chest radiography to patients who cannot be moved to the Radiology department. As such, a mobile x-ray equipment is designed with such unique characteristics to be able to be moved within limited spaces like in between hospital beds in small wards.
An x-ray mobile system consists of a motorized drive, compact wheelbase that includes the generator, an x-ray tube attached to a positioning column and an exposure control panel. As part of this system the image receptor plays a vital role in terms of the image quality and exposure safety (4). Also, different types of detectors can be used such digital radiography (DR) or computed radiography (CR) systems. DR systems have potential to perform examination at a lower dose, they present a high spatial resolution, image quality, lesion-signal response, and a wide dynamic display range when compared to CR systems. The workflow of DR systems is also better when both systems are compared(5).
Specifications of portable x-ray equipment are different among different vendors and the range of products available from the same vendor. Although, there are some common characteristics that could be highlighted as recommendation (Table 1).
|Mobile unit||Type||Mobile X-ray unit with sliding column|
|Focal point distance from floor||55 to 205cm|
|Batteries||Separate batteries for drive and generator control|
|Power for charging||Single-phase|
|Generator and x-ray tube||Power||20 kW|
|Tube voltage||40-125 kV|
|mAs range||0.1 – 500 mAs|
|Exposure times||0.001-1.25 s|
|Focal spot (S/L)||0.3/1.0|
|Wireless portable detector||Type||CsI|
|Detector sizes||35 x 43 cm; 24 x 30 cm|
|Pixel size||148 mm|
|Image resolution||up to 3.4Lp/mm|