CT Scanners Offering Reduced Radiation Dose With Improved Image Quality

New image reconstruction techniques and more efficient, larger detector materials have decreased radiation dosages by more than half, while continuously improving image quality.

The healthcare industry has always been prosperous and substantially dependent on product innovation. CT scanners market is no different, which has tremendous potential across the globe, especially for those vendors who can stay in-sync with the latest technologies. According to Transparency Market Research, the demand in the global CT scanners market is projected to increase at a CAGR of 5.9 percent from 2019 to 2022 to reach a value of USD 6429.8 million by 2022, gaining traction from a number of factors such as increasing preference of the patients for minimally invasive diagnostic procedures, improve healthcare infrastructure in various emerging economies, recent product improvements including the advent of portable CT scanners, and escalating geriatric population who require bedside imaging and home healthcare.

Technological advancements
Evolution of CT from first-generation to advancements like cone beam CT, multidetector CT, higher slice system, new detector technology, iterative reconstruction, spectral CT imaging, data integration (Big Data), integrating information across different diagnostic tools, stereolithography, dual source scanner, dual energy, DICOM structured reporting has led newer-generation portable CT with improved application, precision, accuracy, compactness, lightweight feature, low-dose requirement, improved spatial resolution image quality and speed, reduced artifact and noise, and consumption of far less power. Robustness has enabled portable CT to become  mainstream in medical care. Cost profile of a portable CT is superior to that of a fixed CT scanner.

It is the preferred diagnostic toolkit for head and brain imaging which is faster and efficient compared to other modalities like MRI. It is beneficial from both economical and clinical point of view. Doctors can obviate the risks associated with intra-hospital transport in ICU, NICU, neurointervention suites, intraoperative procedures (decreasing postoperative morbidity), and emergency medicine department enabling high patient throughput, ease of use, feasibility, and cost-effectiveness. A paradigm shift in the utilization of portable CT is its installation in ambulances (stroke ambulances) that can be taken to small towns in the remotest part of the country for real-time imaging, prehospital stroke care, and triage of ischemic and hemorrhagic stroke patients.

Multi-slice CT (MSCT), an advancement of single-slice CT (SSCT), offers real volumetric images in a shorter period of time. However, the radiation dose is higher. The major advantages of MSCT include shorter acquisition times, retrospective creation of thinner or thicker sections from the same raw data set, and improved 3D rendering. The possibilities of MSCT acquisition are widespread, the scan of anatomical volumes with standard techniques at significantly reduced scan times, scanning larger volumes previously not accessible in practical scan times, or the scan of anatomical volumes with high axial resolution.

Current developments and trends show systems with a larger number of slices driven by clinical applications, which become possible through the use of such detectors. Recent systems in the market target these applications by introducing multi-slice systems using different technological paths. These technological improvements offer the possibility to acquire 4D images (3D plus time). There are prototype systems that use a special flat-panel detector technology that was originally used for conventional catheter angiography. As the high radiation dose patients are subjected to is the key problem, the introduction of dynamic collimators will eliminate the increasing problem of over radiation in spiral scans, which has increased as a result of increasing detector width.

Hybrid CT. The technology has evolved side by side and starting from single detector gamma cameras, the market has now multi-detector gamma cameras, with the facility of multimodality fusion in the form of single-photon emission CT (SPECT)/MRI and high-resolution multi-detector CT scanners, intrinsically incorporated into the positron emission tomography-CT (PET CT) systems, capable of providing exquisitely detailed CT anatomy by providing very fine (mm sized) slices. Cancer diagnosis, treatment response evaluation, follow up, and surveillance, all can be accomplished to a large extent by undergoing this single imaging modality which combines at least five (sometimes more) regional CT scans and their functional information in one shot. In non-oncological setting, infection imaging, cardiovascular imaging, and functional imaging of neurodegenerative and neuroinflammatory conditions are amongst few conditions where functional imaging often provides valuable information. Systems are being designed for low-cost clinical applications to very high-resolution research applications with improved detector technologies.

Road ahead
Advancements in image acquisition, analysis, transfer, and storage have put medical imaging at the forefront of medical diagnosis. Patient triage, treatment planning and optimization, and real-time image-guided interventions are now integrated into routine clinical practice in most disciplines. There is a continuous trend toward increased use of CT in medical imaging. Concerns remain regarding the risk of patient exposure to ionizing radiation, and with CT contributing most to medical radiation dose, it is imperative that the market will continue to strive for continuous improvements in patient radiation protection in order to keep radiation exposure as low as reasonably achievable.

Ongoing developments in CT technology have the potential to considerably reduce ionizing radiation exposure to patients. Many recent research studies have focused on the utility of new iterative image reconstruction algorithms in this regard and have highlighted the ability of these new software developments to facilitate the CT scanning at low-doses while maintaining diagnostic image quality. Future research will focus on optimizing these algorithms even further in order to achieve the minimum CT radiation dose without compromising diagnostic ability.

Clinicians are also inclined toward analytics solutions, Artificial Intelligence which will help deliver more value by improving clinical pathways to personalized medicine in the near future. Medical cloud will offer reliability, security, and accessibility on the clinical front. Medical device companies are and will be focusing on high-quality, commercially viable, accessible, and affordable solutions which bring large-scale sustainable, socio-economic, and environment impacting technologies. The challenges and the exciting new opportunities show promise for a bright future ahead.