What is PET-MRI?
Positron emission tomography – magnetic resonance imaging (PET-MRI) can be considered as a hybrid imaging technology that includes MRI soft tissue morphological imaging and positron emission tomography functional imaging.
Brain PET-MRI based on phase:
As of now, the incorporation of positron emission tomography (PET) and magnetic resonance imaging (MRI) as a hybrid imaging modality is getting massive attention in its merging clinical applications and the preclinical field. A couple of designs based on different interesting types of PET detector technologies have been developed over the last couple of years, some of which have been used for first preclinical examinations.
A couple of companies offer MR-compatible preclinical PET scanner embeds for use in the bore of an existing MRI, enabling simultaneous PET/MR image acquisition.
2. Clinical Systems
The first two clinical whole body PET-MRI systems were launched by Philips at Mount Sinai Medical Center in the United States and Geneva University Hospital in Switzerland, in 2010. The system incorporated a PET and MRI scanner isolated by a moving bed. Siemens was the first company to offer simultaneous PET/MR acquisitions, with the primary systems launched in 2010 based on avalanche photodiode detectors.
On 16th February 2013, Apollo Hospitals launched the very first PET-MRI in South Asia. PET-MRI was launched at Indraprastha Apollo Hospitals by the Chief Minister of Delhi, Smt. Sheila Dikshit and is an office supported by the House of Diagnostics. Currently, Siemens and GE are the first company to offer an integrated whole body and coordinate acquisition PET-MRI system. The Siemens system (Biograph MMR) got a CE mark and FDA endorsement for customer purchase in 2011.
Brain PET-MRI based on product:
1. Traditional PET-MRI Systems
In the brain PET-MRI industry, conventional PET-MRI holds a predominant position because of the developing improvement of these instruments by the makers. Top makers, for example, Siemens Healthcare, GE Healthcare, and Bruker have created conventional brain PET-MRI frameworks that take helium to cool the magnet. The utilization of helium in these MRI devices further complex its usefulness and creates different sorts of issues during its installation.
2. Helium-free PET-MRI Systems
Helium-free PET-MRI frameworks are considered to develop massively in the application shortly. The expense of helium gets reduced during the development and utilization of these tools, which is anticipated to decidedly influence its adoption rate across different segments.
To tackle different issues related to customary brain PET-MRI frameworks, top makers are concentrating on improving the advancement of PET-MRI frameworks that are helium-free. Different makers are concentrating on creating helium-free MRI machines, that can be incorporated with PET to make a helium-free PET-MRI machine.
Advantages of PET-MRI systems:
The benefits of combined PET-MRI when compared with conventional imaging methods are many. Some of them are given below:
- Lesser radiation part from MRI.
- Multi-modality preclinical imaging happens in a simultaneous manner.
- Incredible soft-tissue contrast.
- Many tracers are available for PET.
- Permit incredible visualization, measurement, and translational research.
- Cryogen-free magnet use significantly reduces framework needs.
Disadvantages of PET-MRI systems:
Coordinated PET-MRI technology has a few limitations also when we contrast it and other traditional hybrid imaging technologies. A few of the disadvantages are given below:
- It needs a massive initial capital cost.
- There is a lack of convention and standardization as a result of huge variations in MR components.
- No consolidated listing of PET and MR segments.
- Limited adaptability of coordinated PET/MR systems.
- High timings of obtaining of up to 60 min.
Uses of Integrated PET-MRI
- Incorporated PET-MRI has critical applications in oncology. It allows high-resolution imaging of the four key steps in cancer formation namely, apoptosis resistance, cancer angiogenesis, cancer proliferation, and cancer metastasis.
- PET-MRI has its applications in a couple of key clinical and exploration applications in fields such as neurology and cardiology.
- Coordinated PET-MRI imaging modality enables multifunctional and anatomical imaging at the same time in small animals, which significantly impacts biomedical imaging in research and clinical settings.
PET/MRI delivers the potent 'one-stop solution’ blend of anatomical, metabolic, and molecular imaging, which turns out to be better than PET/CT or independent PET system. The post data acquisition including attenuation correction and reconstruction techniques isn't sufficient to infer to the ideal results from it. Also, the weaknesses of the current system must be approached with wonderful designs to layout a superior structure.
The evolvement of PET/MR has applications in the field of Neuroscience, Oncology, Musculoskeletal, and so on, hence, ending up being a frontier in the period of integral hybrid imaging. However, it additionally requires further research on the different utilizations of PET/MRI for pre-clinical and clinical trials.