Setting the record straight about Ezra
Full-body MRI scans are a new tool for early disease detection, capable of finding cancer and other conditions at early stages when treatment can be more effective. However, for you to make an informed decision about which provider to choose you need the facts. This page provides you with important information about Ezra’s full-body MRI service versus Prenuvo’s, focusing on facts (not marketing) to help you make informed decisions - information that you might not otherwise get from Ezra. Where there is a lack of information we have provided our consensus opinion based on our extensive experience in whole body MRI encompassing well over 100,000 patients.
What you don’t know about Ezra that might be important
Ezra’s Medical Team
You may be surprised to hear that Ezra’s Chief Medical Officer is not a radiologist, and the Company does not employ any full-time radiologists in its business (rather they outsource to third party radiologists). By contrast, Prenuvo has invested deeply in medical leadership and considers physician governance critically important to ensuring imaging quality and diagnostic accuracy, particularly in an emerging field such as whole-body MRI. We proudly have a medical group which consists of over 100 licensed providers, including 80+ Board Certified radiologists. Prenuvo’s medical leadership team includes Dr. Daniel J. Durand (CMO - trained at Johns Hopkins), Dr. Amar Patel (VP of Neuroradiology - Stanford), Dr. Ty Vachon (VP of Quality, Safety and Informatics - US Naval Medical Center San Diego), Dr. Vikash Modi (Senior Medical Director of Preventative Medicine - Medical College of Georgia).
The truth about Ezra’s image quality relative to Prenuvo’s on important metrics
Medical image quality is notoriously difficult for consumers to understand. In order to clarify things, we took the images from an Ezra Flash scan and compared them to a Prenuvo comprehensive scan. We evaluated each on four dimensions:
- Voxel count. A voxel, a 3D pixel, is a unit of information about your physiology. The more voxels acquired, the more clinically relevant signal there is.
- Reconstructed voxel count. There are various techniques to accelerate image acquisition (or acquire better images). The most common are compressed sense, parallel imaging and deep learning (in k-space or in image space). Prenuvo takes advantage of all of these techniques (though only performs deep learning in k-space). Ezra imaging will likely depend on the particular machine that is used to acquire their images.
- Tissue-weighted score. A weighting score that rewards the number of different tissue weighting and orientations that are taken of each part of the body. A “weighting” is an image set filtering for blood, fluid, fat, proteinaceous tissue, etc, and an orientation is sagittal, axial or coronal. The more tissue weighting and orientations present, the more medically accurate the radiology can be.
- Diffusion-voxel average counts. Diffusion is a special filter for “hardness” that is particularly important for lesion identification and classification into concerning/benign. A higher count generally leads to greater sensitivity for cancer and fewer false positives.
The logic for these 3 metrics is better explained here: https://prenuvo.com/blog/breaking-it-down-prenuvos-whole-body-mri-screening-explained
Below you will find a comparison of scan across these four metrics.
Ezra doesn’t offer any clinical study data on the effectiveness of its scan
Ezra proudly claims that it “has helped 6% of our members identify potential cancer early”. However to our knowledge Ezra has never published any scientific study reporting on the actual efficacy of its scan - that is, how many of those potential cancers turn out to be cancer and how many actual cancers it misses on average. Without publishing any outcomes-based research, the 6% tells one absolutely nothing about how medically accurate the exam is. Prenuvo by comparison has published extensively, including work on patient outcomes. In our largest study of patient outcomes that followed over 1,000 patients for 1 year, we reported potential cancer in about 2% of screened patients at 1 year follow-up and we found a positive biopsy rate of approximately 50% (about half of patients who reported being biopsied after a Prenuvo scan had found evidence of pathologically proving cancer). The same study found a false negative rate of just 0.2%, suggesting a negative Prenuvo scan offers patients reassurance based on real world evidence.
Ezra doesn’t operate its own facilities - it’s a virtual operation
If you take a look at Ezra’s website you will see imagery of patients checking into what appears to be an Ezra facility, complete with a sign on the wall that reads “Ezra”. Ezra does not operate any of its own facilities, subcontracting instead with various outpatient imaging centers. These imaging centers are not specialized in whole-body image acquisition, operate a wide range of different imaging equipment, and mainly focus on doing more traditional and far simpler outpatient scans like knee MRIs. Thus, patient experience and accuracy may be very different depending on where you happen to live. You can think of Ezra as a “virtual operation”. Prenuvo believes that owning and operating facilities is an important advantage as it enables the selection of optimal hardware, the development of tailored imaging protocols, the standardization of image quality, the hiring and training of high-quality MRI technologists and the provision of an excellent clinic experience for patients.
Ezra doesn’t perform its own radiology
The most important aspect of a whole-body examination is the radiology reading. At Prenuvo, we work with 80+ board certified radiologists, many of whom primarily or even exclusively practice whole-body radiology. Ezra contracts out its radiology to its partner imaging centers for which Ezra radiology is a small part of their business. In fact, many of these imaging centers may screen fewer Ezra patients in a month than a single Prenuvo clinic does in a day. Prenuvo believes that mastery in radiology comes from frequent repetition, particularly for a complex imaging exam like a whole-body examination. Additionally, Prenuvo radiologists work together as a community to improve the quality of whole-body reading, something which is hard to replicate under Ezra’s model. Prenuvo’s internal standards for radiologist quality are extremely stringent. As a group, Prenuvo radiologists perform quality assurance at a rate that is approximately double the industry standard.
Impact of AI in the Ezra imaging exam (or lack thereof)
Ezra claims in various communications that its use of image acquisition AI leads to various benefits including “more accurate early cancer detection” and the ability to achieve the same benefits and image quality from a 30 minute MRI as compared to a far more thorough MRI such as Prenuvo’s 45 minutes Whole Body Scan or a 60 minute MRI. These statements go beyond the marketing claims that Ezra’s FDA clearance allows, notably that these algorithms simply “reduce image noise.” Further, Ezra makes use of these algorithms to noisier, lower resolution scans, which means the use of the algorithm is really intended to reduce scan time and lower costs for Ezra and their partners – even if it means sacrificing the image quality (and, in turn, cancer-detection potential) provided by a 45 or 60 minute MRI scan. Prenuvo believes that deep learning-based image post-processing algorithms should not be employed in a clinical setting because of the risk that the signal of a small but clinically significant pathology (e.g. a small 1 cm cancer) is lost in the noise of the low resolution images acquired.
Putting it all together - Innovating within diagnostic medicine requires full ownership
Whole body MRI is a revolutionary technology that has the potential to change the way people understand and manage their health. But consistently and responsibly delivering high-quality whole body MRI services in the real world requires a rare and nuanced combination of people, process, and technology. Prenuvo has invested heavily in each of these pillars to ensure both the precision and accuracy of our services across the globe: we operate a fleet of essentially identical research-grade MRI machines; we have built standardized protocols for acquiring images, reading scans, and communicating the results and subsequent care pathway recommendations to patients and physicians; we directly employ/contract the professionals who obtain the images and read the scans and care for our patients. Ezra is a virtual operation and has to our knowledge not done all or most of these things. Based on our market-leading level of experience serving over 100,000 patients, we believe that Prenuvo is the better choice in terms of precision, accuracy, and patient outcomes.