<p>In this episode, radiologist/engineer, Raj Attariwala, explains how he was able to apply his engineering background to create a unique MRI scanner that is capable of constructing whole-body images with a resolution that is unmatched in the industry. Peter and Raj discuss the implications of such a robust, radiation-free imaging tool on the early detection of cancer. They dive deep into cancer screening and define terms such as sensitivity and specificity that are necessary to really understand this complex space. They then describe the biggest risks involved in this type of screening (false positives) and how Raj's unique technology and process might drive down this risk substantially. But before that, they discuss all the common imaging technology from X-ray, to CT scan, to PET scans, to ultrasound, to MRI, and more. They touch on the history of each, how they work, the usefulness and limitations of each of them, as well as the varying risks involved such as radiation exposure. If you are interested in cancer screening and/or you've ever wondered how any radiology tool works, this episode is for you.</p> <p> <span style="margin: 0px; font-family: Georgia, serif;">We discuss:</span></p> <ul type="disc"> <li style="font-size: 11pt; font-family: Calibri, sans-serif; margin: 0px;"> <span style="margin: 0px; font-family: Georgia, serif;">Raj's road from engineering to radiology [7:45];</span></li> <li style="font-size: 11pt; font-family: Calibri, sans-serif; margin: 0px;"> <span style="margin: 0px; font-family: Georgia, serif;">How X-ray works, the risk of radiation exposure, and the varying amounts of radiation associated with the different imaging technologies [18:00];</span></li> <li style="font-size: 11pt; font-family: Calibri, sans-serif; margin: 0px;"> <span style="margin: 0px; font-family: Georgia, serif;">Computed tomography scans (CT scans): The history of CT, how it works, and why we use contrast [27:45];</span></li> <li style="font-size: 11pt; font-family: Calibri, sans-serif; margin: 0px;"> <span style="margin: 0px; font-family: Georgia, serif;">Ultrasound: Benefits and limitations, and a special use for the heart [40:45];</span></li> <li style="font-size: 11pt; font-family: Calibri, sans-serif; margin: 0px;"> <span style="margin: 0px; font-family: Georgia, serif;">Detecting breast cancer with mammography: When is works, when you need more testing, and defining 'sensitivity' and 'specificity' [51:15];</span></li> <li style="font-size: 11pt; font-family: Calibri, sans-serif; margin: 0px;"> <span style="margin: 0px; font-family: Georgia, serif;">Magnetic resonance imaging (MRI): How it works, defining terms, and looking at the most common types of MRI [1:03:45];</span></li> <li style="font-size: 11pt; font-family: Calibri, sans-serif; margin: 0px;"> <span style="margin: 0px; font-family: Georgia, serif;">Brain aneurysms: Using MRI to find them and save lives [1:23:45];</span></li> <li style="font-size: 11pt; font-family: Calibri, sans-serif; margin: 0px;"> <span style="margin: 0px; font-family: Georgia, serif;">Raj's unique MRI technology [1:30:00];</span></li> <li style="font-size: 11pt; font-family: Calibri, sans-serif; margin: 0px;"> <span style="margin: 0px; font-family: Georgia, serif;">The risk of false positives in cancer detection, and how Raj's MRI can reduce the number of false positives (i.e., increase specificity) [1:43:40];</span></li> <li style="font-size: 11pt; font-family: Calibri, sans-serif; margin: 0px;"> <span style="margin: 0px; font-family: Georgia, serif;">The unique software Raj created to pair with his MRI machine [1:51:15];</span></li> <li style="font-size: 11pt; font-family: Calibri, sans-serif; margin: 0px;"> <span style="margin: 0px; font-family: Georgia, serif;">Comparing the radiation exposure of a whole-body PET-CT to Raj's equipment (DWIBS-MRI) [1:53:40];</span></li> <li style="font-size: 11pt; font-family: Calibri, sans-serif; margin: 0px;"> <span style="margin: 0px; font-family: Georgia, serif;">How diffusion-weighted magnetic resonance imaging (DW-MRI) has revolutionized cancer screening [1:55:15];</span></li> <li style="font-size: 11pt; font-family: Calibri, sans-serif; margin: 0px;"> <span style="margin: 0px; font-family: Georgia, serif;">Why a DW-MRI is still not a perfect test [1:59:00];</span></li> <li style="font-size: 11pt; font-family: Calibri, sans-serif; margin: 0px;"> <span style="margin: 0px; font-family: Georgia, serif;">The potential for advancing MRI technology: Where does Raj think it could improve in the next 5-10 years? [2:03:00];</span></li> <li style="font-size: 11pt; font-family: Calibri, sans-serif; margin: 0px;"> <span style="margin: 0px; font-family: Georgia, serif;">Are there any commercially available scanners that can match the resolution of Raj's images? [2:06:00];</span></li> <li style="font-size: 11pt; font-family: Calibri, sans-serif; margin: 0px;"> <span style="margin: 0px; font-family: Georgia, serif;">Machine learning: When and where might machine learning/AI impact the field of radiology? [2:08:40]; and</span></li> <li style="font-size: 11pt; font-family: Calibri, sans-serif; margin: 0px;"> <span style="margin: 0px; font-family: Georgia, serif;">More.</span></li> </ul> <p><span style="margin: 0px; font-family: Georgia, serif;"><span style="white-space: pre-wrap;">Learn more at <a href="http://www.peterattiamd.com/">www.PeterAttiaMD.com</a><br /> Connect with Peter on <a href="Facebook.com/PeterAttiaMD">Facebook</a> | <a href="Twitter.com/PeterAttiaMD">Twitter</a> | <a href="Instagram.com/PeterAttiaMD">Instagram</a>.<br /></span></span></p>
Actionable Insights
1. Minimize CT Scans for Young Females
Be aware that younger individuals, especially females, have a greater risk of cancer induction from CT scans, so minimize exposure, particularly in pediatric cases.
2. Electively Screen for Brain Aneurysms
Consider screening for brain aneurysms using MRI, as early detection allows for elective treatment options like coiling or clipping, significantly reducing the high mortality risk associated with rupture.
3. Screen for Aneurysms with Family History
If there is a family history of aneurysms, especially at a young age, consider MRA (magnetic resonance angiography) screening due to a potential genetic component, even if insurance initially declines coverage.
4. Personalize Cancer Screening Decisions
Understand that cancer screening is a very personal decision with risks, particularly false positives leading to emotional distress and potential harm, so approach it thoughtfully.
5. Combine Mammogram and DWI MRI
For comprehensive breast cancer screening, combine mammography (to detect calcifications) with a high-quality diffusion-weighted imaging (DWI) MRI, as this combination is highly sensitive and unlikely to miss cancer.
6. Consider Additional Imaging for Dense Breasts
If you have dense breast tissue, a mammogram might not be sufficient, so consider additional imaging modalities like ultrasound or MRI to effectively screen through the glandular tissue.
7. Know Your Breast Density
Understand your breast density, as mammogram sensitivity is significantly lower (around 55%) for dense breast tissue compared to fatty tissue (over 95%), impacting the test’s effectiveness.
8. Check Mammogram for Density
Always check your mammogram report for information on breast tissue density, as this detail helps you understand if the mammogram alone is sufficient for effective screening.
9. Get Regular Mammograms
Get mammograms at regular intervals (one or two years) because comparing images over time is far more sensitive for detecting subtle changes than evaluating a single mammogram.
10. Early Breast Screening for Family History
If you are under 40 and have a family history of early-age breast cancer, consider discussing screening options, as standard mammography guidelines often exclude this age group.
11. Consider Prostate MRI Screening
Explore MRI with diffusion-weighted imaging (DWI) for prostate cancer screening, as it is becoming a de facto standard in some countries for better differentiation of aggressive versus indolent cancers.
12. Be Cautious About MRI Quality
Be aware that MRI quality and standardization vary significantly between clinics and machines, unlike CT scans, so research and choose your MRI provider carefully.
13. Know Imaging Radiation Exposure
Understand that different imaging technologies, like X-rays or mammograms, expose you to varying amounts of radiation, generally increasing from simple X-rays to whole-body PET-CTs.
14. Calculate Personal Radiation Dose
Use an online calculator to determine your personal radiation dose from various exposures, including medical imaging and travel, as this is a requirement for professions like pilots.
15. Seek Clear Imaging Answers
When undergoing imaging, aim for technologies that provide clear ‘yes or no’ answers regarding potential problems, such as combining functional and anatomic imaging for definitive diagnoses.
16. Embrace AI for Longitudinal Imaging
For repeat scans, machine learning can significantly improve efficiency by performing ‘subtraction’ analysis to highlight subtle differences over time, helping to detect changes more easily.
17. Utilize AI for Imaging Review
Be open to the future integration of machine learning and AI as a ‘second reader’ for imaging, which aims to improve radiologist efficiency and reduce missed diagnoses, similar to its current use in mammography.
18. Understand Medical Imaging
Listen to this technical episode if you’ve ever had an X-ray, CT scan, ultrasound, or MRI, as it provides crucial understanding of these technologies that most doctors don’t fully grasp.
19. Utilize Show Notes for Visuals
Refer to the show notes for this episode, as they will pair discussions with images to help visualize and understand complex radiology concepts, especially MRI.
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