Electronic Military & Defense magazine was developed for engineers, program managers, project managers, and those involved in the design and development of electronic and electro-optic systems for military, defense, and aerospace applications.
Issue link: https://electronicsmilitarydefense.epubxp.com/i/707574
Trends with respect to critical organs before moving the patient (i.e., in the field) is likely to have a material impact on patient well-being, considering that shrapnel readily migrates within the body, potentially causing further damage. As such, aides in localizing structures and providing estimations of foreign object position and size are required in the field. The ability to view a comprehensive 3D image of any area before surgery also limits unexpected outcomes in the operating theater and increases the efficiency of treatment. 15,16,17,18,19 There are several diagnostic tools available for shrapnel detection, including general X-ray imaging, computed tomography imaging (CT), ultrasound, and angiography. These tools are used in a hospital setting before surgery for shrapnel removal or directly following a blast injury event. Ultrasound currently is the best imaging method to use in determining the relationship between the shrapnel and other structures in the body, such as tendons. The introduction of ruggedized, handheld ultrasound devices by SonoSite in 1999 transformed diagnostic capability on the modern battlefield. 1 Metal detectors have also been used and are the most portable device for shrapnel detection but, as with the Geiger counter, will not detect metal deep in the body or inform of the shrapnel's relative anatomical position. Non- metallic shrapnel also would not be detectable. Magnetic resonance imaging (MRI), normally a critical tool for surgical planning, is unsuitable for imaging shrapnel, as the strong magnetic fields used may move the shrapnel inside the body, causing further injury. MRI equipment is bulky and difficult to deploy in field-forward hospitals. X-rays, meanwhile, are the oldest and most commonly used form of non-invasive medical imaging and have recently shown promise for in-the-field use. X-ray radiation passes through the body to image a person's internal structure, depending on the degree of interaction with the variable density organic material. Such methods allow the presence, size, and location of areas of interest to be imaged in detail. 20 The importance of radiology in field medicine was first recognized in the Second Boer War (1899-1902), and it was subsequently used in World War I by army surgeons, who quickly became accustomed to working with radiologists in a team. Medical imaging techniques, such as X-ray imaging, are currently invaluable patient management methods within the golden hours of a combat emergency for first responders in combat casualty care, as well as civilian disaster medical support, helping to image the site and measure the extent of the injury, which feeds into emergency surgery decisions. 9,21,22,23 X-ray CT in military hospitals was used for the first time during Operation Desert Storm in the Saudi Arabian desert, and it remains the gold standard for trauma imaging. 14 However, CT equipment is heavy and bulky, making it difficult to deploy. Digital systems, advances in low-power sources, and the increasing importance and prevalence of portable X-ray systems (Figure 2) are changing the future potential of X-ray imaging in Role 1 battlefield imaging applications. 24 Mobile healthcare technology, such as tomosynthesis and its 3D imaging capability, should allow faster processing and transport of patients, improved accuracy of triage, and better monitoring of the unattended at a disaster scene, improving scarce transportation and human resource allocation in high-risk arenas for improved patient care and survival outcomes. 13,21,25 X-ray tomosynthesis uses multiple projections acquired over a limited range of angles to image a stationary patient. 26 As such, tomographic images can be rendered in 3D (similar to CT), with high in-plane spatial resolution, obtained at low dose and with scanning times of approximately 10 seconds, using a moving source. 27 Tomography, combined with novel technologies for automated shrapnel localization and quantification, potentially adds to the arsenal of decision-making tools for enhancing patient care, especially where prompt diagnosis and treatment of medical and surgical conditions is required. Existing tomosynthesis systems rely on motorized tube-based X-ray sources, which reduce the systems' ease of mobility. However, it now is possible to realize a rugged, compact, lightweight, and portable X-ray-based diagnostic 3D imaging system, with wireless integration and versatility of power source, for use in the field for war zones, disasters, and emergency settings (Table 1 and Figure 3 compare various available technologies). Advancements in X-ray source technology allow motion- free tomosynthesis with lightweight distributed sources. The enhanced diagnostic 3D imaging capability will accurately localize shrapnel/foreign bodies in relation to anatomic structures to better determine the approach for their removal. Using innovative image reconstruction techniques, the field image will be of sufficient quality (high sharpness and signal-to-noise) to allow a go/no-go decision with respect to transporting the patient for further treatment or assessment across a diverse range of battlefield settings and mass casualty events. 1,8,21 For shrapnel detection, a panel X-ray source (either curved or flat), comprising an array of emitters across the Electronic Military & Defense Annual Resource, 6th Edition 21 Figure 2: Examples of "portable" X-ray imaging systems: (left) MinXray 2D conventional source, and (right) Adaptix conceptual mobile tomosynthesis distributed motion-free source.