On this 115th anniversary of the discovery of X-rays, Health Imaging Hub is going to highlight some concepts and details of medical imaging and its advancement at the present time. Medical imaging and related technology is not a story to tell in few lines, it is a concept that involves multiple industries and stakeholders all over the world. Here is a brief introduction to the medical imaging and related disciplines and how the technology will help in coming years in achieving better patient care.
Simply put, Medical Imaging is process of obtaining body images for medical information purposes. Medical imaging includes all sort of imaging (radiology, pathology, endoscope, etc), but the term is widely used to in radiology sciences which is what we are going to discuss.
Medical Imaging in Radiology
The dream of obtaining clear, sharp and fully-detailed medical imaging of the human body internal organs to serve various medical needs came true by inventing and developing means of medical imaging technology. Proper medical imaging providing diagnosis, classification, pre and post operative assessment requires accurate and sensitive imaging with reduced cost and less harm to the patient. Development through ionizing radiation (x-ray and computed tomography) into non-ionizing radiation (ultrasound and magnetic resonance imaging) enabled more features and options that were not available before. The development of contrast media adds more to the sensitivity and specification of the medical imaging techniques. Advanced medical imaging with combination between different imaging modalities even created superior medical imaging advantage over time. Radiology is even used in therapeutic purpose rather than just medical imaging in multiple medical hazards, especially malignancy.
Medical Imaging Equipment
Since the discovery of x-rays by Roentgen, the intelligent minds never stopped designing and creating new facilities for better medical imaging visualization, accurate medical diagnosis and less hazards among the patients. The worldwide propagation of medical services and the great demand for proper medical imaging inspired scientists to develop reliable and robust equipment with user-friendly interface for proper distribution all over the globe.
The x-ray machines gradually developed from low KV tube into high ones producing sharper medical imaging, and the needs for direct visualization encouraged further supplementing with screens producing what is called medical imaging fluoroscopy for direct and live visualization of the internal organs of the human body. Interventional radiology raised the need of developing the medical imaging fluoroscopy into continuous imaging through C arms that enabled minor surgical procedure to be done. The scientific revolution and the widespread of computers made a touch over x-ray machines with invention of digital medical imaging through computed radiography (CR) technique with replacement of ordinary sensitive films by imaging plate, producing sharper medical imaging slides with better details and information. With usage of contrast media, further diagnosis could be obtained through medical imaging of hollow organs and tracts. Due to its reliability and essentiality, x-ray equipment are considered the most commonly available and well distributed medical imaging tool all over the world beside the ultrasound equipments.
Ultrasound was initially invented for military and exploratory purposes, and the medical need for safe imaging tools diverted the interest of ultrasound waves into the medical imaging field. Different modes were developed over years to provide the optimum medical imaging required for proper diagnosis. With its reliability, fast performing, low cost and portable availability, ultrasound equipment are widely spread globally. The invention of multiple transducers enabled access to different regions providing high resolution medical imaging that facilitated the diagnostic process. Obstetrical medical imaging is one the great advantages of the ultrasound among other medical imaging modalities because of its safe procedure over the pregnant woman as well as the fetus. Color Doppler also made a huge step for non-invasive vascular medical imaging which is of great value.
Computed tomography (CT) is a natural development of x-rays, using the same physical source with aid of technology and computers to produce a highly advanced medical imaging beam that enabled soft tissue characterization. Through time the development process crossed the conventional to spiral and multi-slice to dual equipment. The dependence on computers enabled coronal and sagittal reconstruction of axial medical imaging, and further more 3D reconstruction which added more medical benefit for both physicians and patients. Advanced techniques as CT angiography and virtual studies enrich the value of computed tomography. Unfortunately, its dependence on ionizing radiation limits its utilization among certain subjects, but current studies are carried out to reduce radiation doses.
Magnetic Resonance Imaging (MRI) is a unique form of medical imaging that depends on magnetic field and complicated imaging technique. Its main advantage is the safety with no radiation hazards. Although it has some limitations in cases with metallic prostheses and pacemakers, still the technique is of great medical imaging advantage due to its superior soft tissue characterization which is mainly implicated in joints medical imaging. The ability of multi-planning, axial, sagittal and coronal without reconstruction generated obvious medical imaging enhancement with better diagnoses. Magnetic resonance angiography and venography added a new non-invasive vascular medical imaging procedure.
Scintigraphy is also one of the medical imaging forms, although it measures the radiation from the patients body itself. It is implicated in multiple systemic monitoring for function and medical assessment. A special interest is made upon the metastasis in cancer suffering patients.
Modern medical imaging modalities like positron emission tomography (PET) and merging computed tomography (PET-CT) are of great medical imaging value in neoplastic diseases and assess metastatic conditions as well as measuring viability of suspected lesions.
Medical Imaging IT & Software
The overspread of healthcare IT in medical field raised the interest in applying the technology into medical imaging. Many software and applications are created to enhance the images towards better medical imaging diagnoses through advanced imaging reconstruction, subtraction and colors adding. Even more, the demand of organization of radiological data popped up the idea of creating what is called radiology information system (RIS) which is designed to organize the medical imaging workflow inside radiology departments within hospitals and institutions.
The progressive demand for proper archiving and viewing the medical imaging created by different radiological modalities, the picture and archiving system (PACS) is created to facilitate medical imaging storage in an editable form with easy access and transportation. Many universities and engineering departments are working on healthcare IT projects seeking the medical service propagation through medical imaging studies.
Medical Imaging, From a Global Perspective
The critical and vital role of medical imaging in diagnosis and medical assessment forced the installation of medical imaging equipment all over the world even inside the primary care facilities. With lack of experienced radiologists to properly diagnose and provide medical information needed by physician, the concept of telemedicine had to play its role.
Telemedicine is designed to support regions in need of medical service using telecommunication, especially the internet. The imaging portion of tele-medicine is named as tele-radiology services. The association between communication and healthcare IT software enabled a stable platform for viewing medical imaging anywhere in the world with full detailed report delivering to the concerned physician before medical intervention or treatment decision.
The cycle of development is running over serious researches to add more value and medical advantages over the current medical imaging modalities and technology, the near future will carry more and more medical imaging facilities.
Dr. Mohamed El-Refaey, MSc