Scanning the Horizon

Ultra-high-end MRI systems will create a new MRI market segment, bringing a paradigm shift in imaging across existing as well as new clinical areas.

For decades now, magnetic resonance imaging (MRI) has been noted for its excellent soft-tissue imaging capability with zero radiation dose. It has been called the imaging modality of the future over and over, but due to its complexity, long exam times, and high cost, its growth has been severely limited. The global market is currently experiencing steady growth (mid-single-digit growth rate). Although economic uncertainty and budgetary constraints have slowed down the market in certain countries, technological innovation and extended/new clinical applications of MRI due to their high importance in the imaging space have enabled it to overcome the restraints.

Over the years, Indian medical imaging equipment market has been growing at a robust pace on account of rising demand from hospitals, increasing incidence of chronic diseases, and introduction of hybrid imaging systems. Indian medical imaging equipment market is projected to cross
USD 1.6 billion by 2021. Rising number of global players foraying into the country, coupled with escalating number of applications of diagnostic imaging systems and rising healthcare expenditure, has also been fueling demand for medical imaging equipment in the country. Moreover, growing awareness regarding early diagnosis of diseases among people and increasing technological advancements is expected to drive the medical imaging equipment market in India in the coming years.

Recent national initiatives provide robust growth opportunities for the Indian medical devices industry, including medical imaging equipment. With 100 percent FDI allowed in medical devices industry, India is emerging as an attractive hub for foreign companies to set up their research and manufacturing facilities. Backed by all these factors, Indian medical imaging equipment market is anticipated to grow at a robust pace over the next five years.

Indian Market Dynamics
The Indian MRI equipment market is estimated at 1632 crore, at 380 units in 2016. The 1.5T systems continue to be popular with a 63 percent value share, and a 68 percent volume share in this segment. 3T systems, which are seeing fast growth have a 25 percent value share and an 11.3 percent volume share. The 0.2T–0.5T systems, although gradually perceived as exiting this segment, continue to maintain presence with a 2 percent share in the Indian market. The refurbished segment constitutes the balance share. Indian market has not yet procured any 7T system.

GE, Philips, and Siemens have a combined share of 95 percent in the Indian market; the balance is shared by Hitachi and Toshiba.

The digital MRI systems with advanced clinical outcomes and new imaging protocol workflows are gaining preference. The discerning customer appreciates the flexibility of adjusting and retrospectively correcting the scan. A higher-speed system takes almost one-third the time of the conventional scan. The only noise a patient hears in a silent MRI is the room level noise. Awareness that MRI imaging capacity can be expanded through data-driven workflow optimization is removing major operational bottlenecks at the facilities.

Global Market Dynamics
Developing nations focused on investing in their healthcare infrastructure should spur growth in the global market for medical MRI. BCC Research reveals that countries, such as China, India, Brazil, and the Middle- East, represent opportunities for growth in the MRI market. The market should reach nearly USD 6.1 billion and USD 8 billion in 2016 and 2021, respectively, growing at a five-year compound annual growth rate (CAGR) of 5.7 percent.

The North American market for MRI systems should reach USD 3.1 billion in 2021 and USD 2.4 billion in 2016, growing at a five-year CAGR of 5.4 percent. The MRI systems market in the Asia-Pacific region is expected to reach USD 2.1 billion in 2021, up from USD 1.5 billion in 2016, growing at a five-year CAGR of 7.3 percent.

Wide-bore magnetic resonance imaging systems comprise over 85 percent of the US medical imaging market. The US market for MRI systems includes low-, mid- and high-field MRI systems as well as wide-bore and closed-bore MRIs for all field strengths. Growth in this market is driven by a shift toward mid- and high-field strength systems as they become more and more accessible to various consumers due to declines in average selling prices.

Mid-field MRI systems represent the largest medical imaging market in the US and will continue to experience steady growth. Mid-field systems are projected to lose some market share as purchasers shift to improved high-field systems, but mid-field systems will still maintain stable market growth until 2022. However, low-field MRI systems are rapidly declining as these systems are becoming obsolete due to both their low image quality compared to mid-field and high-field systems, and the accelerating growth in the refurbished market for mid-field systems. Similar to mid-field systems, closed-bore systems will lose market share to wide-bore systems as their popularity continues to grow. The ASP of these systems will continue to fall due to competition from higher-field systems.

Improving socioeconomic conditions in emerging regions and substantial investments by their governments in building and enhancing their healthcare infrastructure have increased demand for medical imaging systems.

Three Big Predictions

• The commercial launch of ultra-high-end MRI systems (for example, 7T and 9T – currently used for research purpose) during 2016–2020 will create a new MRI market segment, bringing a paradigm shift in imaging across existing as well as new clinical areas.
• While MRI for neurology and brain disorders dominates the current market (about 35–41%), the use of MRI in cardiac, abdominal, lung, and breast imaging is expected to triple over the next four years extending the use of MRI in new clinical applications.
• Improvements in MRI systems such as high-performance gradients, surface coils, reduction techniques in terms of noise, artifacts and dosage, coupled with parallel imaging techniques and imaging informatics have substantially increased the level of quality and speed of image acquisition, thereby boosting the clinical performances.

Technology Update – Throwing out the Ideal Scanner
Despite decades of massive investment, traditional MRI still yields only qualitative images that are not resolved enough to guide database-driven diagnoses and research in the age of big data.

A new effort to overcome these challenges began with work led by Mark Griswold at Case Western Reserve University and published in Nature, which described magnetic resonance fingerprinting (MRF). Prior to that, MRI scanners had to wait for the magnetic spins to return to their normal equilibrium between each sequential radio wave pulse, a profound hindrance to imaging speed. MRF instead built images from the complex interplay of overlapping signals, a distinctive fingerprint matched to tissue qualities.

With advances in computation, MRF images were built on a small fraction of the scanner data matched to databases of known tissue patterns. The method replaced slower approaches required to process all the data to build an image from scratch. Despite this innovation, the first author of the current paper, NYU Langone magnetic resonance (MR) physicist Martijn Cloos, PhD, who is also an assistant professor in the Department of Radiology, saw that MRF was held back by its attempt match the real spins it captured to patterns from a simulated scanner calibrated to offer perfectly uniform exposure.

Unable to force uniformity, MRF images did not always reflect reality. To correct this, Cloos and colleagues designed Plug-and-Play MR Fingerprinting (PnP-MRF), which embodied their decision to throw out the ideal scanner.

Described in the newly published study, PnP-MRF matches its measurements to a simulated database of every possible magnetic field interaction or distortion as it builds images, and so requires zero calibration. Along with capturing spin characteristics, the new method was shown to effectively map the distortions that occur as MR radio waves interact with tissue, which radiologists had previously sought to erase via calibration. The study authors argue that these same field distortions also serve as a new set of tissue parameters that can aid in diagnoses.

Where MRF used a single source of radio wave pulses to generate signals, PnP-MRF is a circling strobe light of many broadcast magnetic fields, hitting the atoms from different directions separated by milliseconds to create a new kind of fingerprint. An artifact introduced by any one radio wave pulse may show a dark spot in one version of an image, but not in the same place in all data sets, enabling the dismissal of errors.

Taken together, these innovations enable PnP-MRF to correct for each scanner’s peculiarities and magnetic field-tissue interactions, conclusions confirmed by a series of numerical and tissue experiments.

“In our design, the complexity in creating MRI images has moved from the machinery to the computation,” says Cloos, “Rather than building chambers to house extensive magnet coils that fight non-uniformities, near-future scanners, by embracing heterogeneous fields, will consist of simple tabletop magnets, or possibly even hand-held MRI wands.”

Way Ahead
MRI has continued to rapidly develop since its introduction as a clinical tool in the early 1980s. Technological advancements have helped it to emerge as a standard diagnostic technique in the global healthcare system. The technology has a clear edge over other modalities such as CT due to its non-ionizing nature, enabling its use in high-risk as well as pediatric patients. The technique also allows anatomic as well as functional imaging that allows its application in perfusion and diffusion imaging as well as navigation and planning in surgery. Widespread use of 3T scanners is already becoming a reality and future developments in coil technology and new image contrasts will continue to provide new tools for clinical diagnosis. The future holds good for MRI with ultras high-field systems with 7T and 9.4T systems currently being evaluated. Combined modalities and targeted contrast media are further on the clinical horizon, but will become a reality for specialist referral centers in the coming years.

Second Opinion