From eye exams to blood tests and surgery: how doctors use light to diagnose disease
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This is the next article in our ‘Light and health’ series, where we look at how light affects our physical and mental health in sometimes surprising ways. Read other articles in the series.
You’re not feeling well. You’ve had a pounding headache all week, dizzy spells and have vomited up your past few meals.
You visit your GP to get some answers and sit while they shine a light in your eyes, order a blood test and request some medical imaging.
Everything your GP just did relies on light. These are just some of the optical technologies that have had an enormous impact in how we diagnose disease.
1. On-the-spot tests
Point-of-care diagnostics allow doctors to test patients on the spot and get answers in minutes, rather than sending samples to a lab for analysis.
The “flashlight” your GP uses to view the inside of your eye (known as an ophthalmoscope) is a great example. This allows doctors to detect abnormal blood flow in the eye, deformations of the cornea (the outermost clear layer of the eye), or swollen optical discs (a round section at the back of the eye where the nerve link to the brain begins). Swollen discs are a sign of elevated pressure inside your head (or in the worst case, a brain tumour) that could be causing your headaches.
The invention of lasers and LEDs has enabled many other miniaturised technologies to be provided at the bedside or clinic rather than in the lab.
Pulse oximetry is a famous example, where a clip attached to your finger reports how well your blood is oxygenated. It does this by measuring the different responses of oxygenated and de-oxygenated blood to different colours of light.
Pulse oximetry is used at hospitals (and sometimes at home) to monitor your respiratory and heart health. In hospitals, it is also a valuable tool for detecting heart defects in babies.
2. Looking at molecules
Now, back to that blood test. Analysing a small amount of your blood can diagnose many different diseases.
A machine called an automated “full blood count analyser” tests for general markers of your health. This machine directs focused beams of light through blood samples held in small glass tubes. It counts the number of blood cells, determines their specific type, and reports the level of haemoglobin (the protein in red blood cells that distributes oxygen around your body). In minutes, this machine can provide a snapshot of your overall health.
For more specific disease markers, blood serum is separated from the heavier cells by spinning in a rotating instrument called a centrifuge. The serum is then exposed to special chemical stains and enzyme assays that change colour depending on whether specific molecules, which may be the sign of a disease, are present.
These colour changes can’t be detected with the naked eye. However, a light beam from an instrument called a spectrometer can detect tiny amounts of these substances in the blood and determine if the biomarkers for diseases are present, and at what levels.
3. Medical imaging
Let’s re-visit those medical images your GP ordered. The development of fibre-optic technology, made famous for transforming high-speed digital communications (such as the NBN), allows light to get inside the body. The result? High-resolution optical imaging.
A common example is an endoscope, where fibres with a tiny camera on the end are inserted into the body’s natural openings (such as your mouth or anus) to examine your gut or respiratory tracts.
Surgeons can insert the same technology through tiny cuts to view the inside of the body on a video screen during laparoscopic surgery (also known as keyhole surgery) to diagnose and treat disease.
How about the future?
Progress in nanotechnology and a better understanding of the interactions of light with our tissues are leading to new light-based tools to help diagnose disease. These include:
- nanomaterials (materials on an extremely small scale, many thousands of times smaller than the width of a human hair). These are being used in next-generation sensors and new diagnostic tests
- wearable optical biosensors the size of your fingernail can be included in devices such as watches, contact lenses or finger wraps. These devices allow non-invasive measurements of sweat, tears and saliva, in real time
- AI tools to analyse how blood serum scatters infrared light. This has allowed researchers to build a comprehensive database of scatter patterns to detect any cancer
- a type of non-invasive imaging called optical coherence tomography for more detailed imaging of the eye, heart and skin
- fibre optic technology to deliver a tiny microscope into the body on the tip of a needle.
So the next time you’re at the GP and they perform (or order) some tests, chances are that at least one of those tests depend on light to help diagnose disease.
Matthew Griffith, Associate Professor and ARC Future Fellow and Director, UniSA Microscopy and Microanalysis Facilities, University of South Australia
This article is republished from The Conversation under a Creative Commons license. Read the original article.
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10 Healthiest Foods You Should Eat In The Morning
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For many of us, our creative minds aren’t their absolute best first thing in the morning, and it’s easy to reach for what’s available, if we haven’t planned ahead.
So here’s some inspiration for the coming week! If you’re a regular coffee-and-toast person, at least consider alternating some of these with that:
- Oatmeal with fresh fruit: fiber, energy, protein, vitamins and minerals (10almonds tip: we recommend making it as overnight oats! Same nutrients, lower glycemic index)
- Greek yogurt parfait: probiotic gut benefits, along with all the goodness of fruit
- Avocado toast: so many nutrients; most famous for the healthy fats, but there’s lots more in there too!
- Egg + vegetable scramble: protein, healthy fats, vitamins and minerals, fiber
- Smoothie bowl: many nutrients—But be aware that blending will reduce fiber and make the sugar quicker to enter your bloodstream. Still not bad as an occasional feature for the sake of variety, though!
- Wholegrain pancakes: energy, fiber, and whatever your toppings! Fresh fruit is a top-tier choice; the video suggests maple syrup; we however invite you to try aged balsamic vinegar instead (sounds unlikely, we know, but try it and you’ll see; it is so delicious and your blood sugars will thank you too!)
- Chia pudding: so many nutrients in this one; chia seeds are incredible!
- Quinoa breakfast bowl: the healthy grains are a great start to the day, and contain a fair bit of protein too, and served with nuts, seeds, and diced fruit, many more nutrients get added to the mix. Unclear why the video-makers want to put honey or maple syrup on everything.
- Berries: lots of vitamins, fiber, hydration, and very many polyphenols
For a quick visual overview, and a quick-start preparation guide for the ones that aren’t just “berries” or similar, enjoy this short (3:11) video:
Click Here If The Embedded Video Doesn’t Load Automatically!
PS: They said 10, and we only counted 9. Where is the tenth one? Who would say “10 things” and then ostensibly only have 9? Who would do such a thing?!
About that chia pudding…
It’s a great way to get a healthy dose of protein, healthy fats, antioxidants, and a lot of other benefits for the heart and brain:
The Tiniest Seeds With The Most Value
Enjoy!
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Q&A with the 10almonds Team
Q: Very interested in this article on CBD oil in the states. hope you do another one in the future with more studies done on people and more information on what’s new as far as CBD oil goes
A: We’re glad you enjoyed it! We’ll be sure to revisit CBD in the future—partly because it was a very popular article, and partly because, as noted, there is a lot going on there, research-wise!
And yes, we prefer human studies rather than mouse/rat studies where possible, too, and try to include those where we find them. In some cases, non-human animal studies allow us to know things that we can’t know from human studies… because a research institution’s ethics board will greenlight things for mice that it’d never* greenlight for humans.
Especially: things that for non-human animals are considered “introduction of external stressors” while the same things done to humans would be unequivocally called “torture”.
Animal testing in general is of course a moral quagmire, precisely because of the suffering it causes for animals, while the research results (hopefully) can be brought to bear to reduce to suffering of humans. We’re a health and productivity newsletter, not a philosophical publication, but all this to say: we’re mindful of such too.
And yes, we agree, when studies are available on humans, they’re always going to be better than the same study done on mice and rats.
As a topical aside, did you know there’s a monument to laboratory mice and all they’ve (however unintentionally) done for us?
❝The quirky statue depicts an anthropomorphic mouse as an elderly woman, complete with glasses balanced atop its nose. Emerging from two knitting needles in its hands is the recognizable double-helix of a strand of DNA.❞
~ Smithsonian Magazine
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The Insomnia Breakthrough – by Katherine Coleman
10almonds is reader-supported. We may, at no cost to you, receive a portion of sales if you purchase a product through a link in this article.
The author, a massage therapist, knows plenty about relaxation. But how to put that to use when it comes to getting good quality sleep?
She takes a holistic approach, and yes, does start by covering all the things you’d expect to find in any guide to better sleep (aim for regular schedule, have darkness when you sleep, cool room, clean sheets, no alcohol or caffeine before bed, etc).
What she offers in particular beyond that, is the integration of calming routines, building in mindfulness for sleep (when very often people will go for the opposite!), and small cumulative lifestyle adjustments that are conducive to getting a better night’s rest every night.
The style is very light pop-science (as one might expect from someone who is not, in fact, a scientist), and while we do get a bibliography at the back, it’s a meagre 4 pages. Nevertheless, there’s a lot of interdisciplinary knowledge here, explained well.
Bottom line: if improving your sleep is something you’d like to do, this book can almost certainly get you on the right track.
Click here to check out The Insomnia Breakthrough, and don’t stay up too late reading it!
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Thriving Beyond Fifty – by Will Harlow
10almonds is reader-supported. We may, at no cost to you, receive a portion of sales if you purchase a product through a link in this article.
We’ve featured this author sometimes in our video section; he’s an over-50s specialist physiotherapist with a lot of very functional advice to offer.
In this book, Harlow focusses heavily on three things: mobility, strength, endurance.
You may not want to be a gymnast, powerlifter, or marathon-runner, but these things are important for us all to maintain to at least a fair degree:
- Mobility can be the difference between tweaking one’s shoulder getting something from a high shelf, or not
- Strength can be the difference between being able to get back up, or not
- Endurance can be the difference between coming back from a long day on your feet and thinking “that was a good day; I’m looking forward to tomorrow now”, or not
One of the greatest strengths of this book is its comprehensive troubleshooting aspect; if you have a weak spot, chances are this book has the remedy.
As for the style, it’s quite casual/conversational in tone, but without skimping on science and detail. It’s clear, explanatory, and helpful throughout.
Bottom line: if you’d like to maintain/improve mobility, strength, and endurance, then this book is a very recommendable resource.
Click here to check out Thriving Beyond Fifty, and keep thriving at every age!
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Foods That Cause You to Lose Weight – by Dr. Neal Barnard
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We previously reviewed Dr. Barnard’s “The Power Foods Diet”, and this time his work is about weight loss.
This time there are more recipes (which take up most of the book, so this one could be reasonably described as a cookbook), but not until after nearly a hundred pages of concepts, principles, and tips.
The recipes themselves are again very respectable, even if some may be a little redundant (e.g. the double-page recipe for blueberry muffins is followed by a double-page recipe for banana and date muffins, instead of just saying “or substitute this”—things like that) and run the gamut from salad dressings to hearty main meals.
A strength of the book is that it’s about what you eat, not how much of it you eat, so if you love eating (which is a very healthy trait to have in general), then you’ll enjoy that aspect.
Bottom line: if you’d like to eat more and weigh less, then this is a top-tier book for you.
Click here to check out “Foods That Cause You To Lose Weight”, and enjoy eating!
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How Gluconolactone Restores Immune Regulation In Lupus
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Let’s be clear up front: this will not cure lupus.
However, it will interrupt the pathology of lupus in such a way as to, as the title says, restore immune regulation—so that your body stops attacking itself, or at the very least, attacks itself significantly less.
What is gluconolactone anyway?
Gluconolactone (also called glucono-δ-lactone) an oxidized derivative of glucose, when glucose is exposed to oxygen and a certain enzyme (glucose oxidase). It’s used in various food-related fermentation processes, and also helps such foods to have a tangy flavor.
It’s also known as E575, showing that E-numbers need not always be scary 🙂
How does it work?
First, a recap on how lupus works: lupus is an autoimmune disease where the immune system attacks its own tissues, causing inflammation and organ damage (to oversimplify it in very few words).
Next, how lupus is currently treated: mostly with immunosuppressant drugs, which reduce symptoms but have significant side effects, not least of all the fact that your immune system will be suppressed, leaving you vulnerable to infections, cancer, aging, and the like. So, there’s really a “damned if you do, damned if you don’t” aspect here (because untreated lupus will run your immune system into the ground with its chronic inflammation, which will also leave you vulnerable to the aforementioned things).
See also: How to Prevent (or Reduce) Inflammation
Now, how gluconolactone works: it increases the number of regulatory T-cells (also called “Tregs” by scientists who don’t want to have to say/write “regulatory T-cells” many times per day), which are the ones that tell the rest of your immune system what not to attack. It also inhibits pro-inflammatory T-helper-cells that are otherwise involved in autoimmune dysfunction.
Where is the science for this?
It’s a shiny new paper that covers three angles:
- In lupus-suffering mouse in vivo studies, it improved Treg function and reduced inflammatory skin rashes
- In human cell culture in vitro studies (with cell cultures from human lupus patients), it bolstered Treg count and improved immune regulation
- In human patient in vivo studies, a gluconolactone cream controlled skin inflammation and improved the clinical and histologic appearance of the skin lesions within 2 weeks
❝These results suggest that gluconolactone could be a targeted treatment option with fewer side effects for autoimmune diseases such as lupus.
Gluconolactone acts like a ‘power food’ for regulatory T cells—a real win-win situation for immune regulation❞
~ Dr. Antonios Kolios
You can find the paper itself here:
Where can I get gluconolactone?
At the moment, this is still in the clinical trials phase, so it’s not something you can get a prescription for yet, alas.
But definitely keep an eye out for it!
We would hypothesize that eating foods fermented with E575 (it’s sometimes used in feta cheese, hence today’s featured image, and it’s also often used as a pickling agent) may well help, but that’s just our hypothesis as it isn’t what was tested in the above studies.
Want to learn more?
In the meantime, if you’d like to learn more about lupus, we recommend this very comprehensive book:
*The “et al.” are: Jemima Albayda, MD; Divya Angra, MD; Alan N. Baer, MD; Sasha Bernatsky, MD, PhD; George Bertsias, MD, PhD; Ashira D. Blazer, MD; Ian Bruce, MD; Jill Buyon, MD; Yashaar Chaichian, MD; Maria Chou, MD; Sharon Christie, Esq; Angelique N. Collamer, MD; Ashté Collins, MD; Caitlin O. Cruz, MD; Mark M. Cruz, MD; Dana DiRenzo, MD; Jess D. Edison, MD; Titilola Falasinnu, PhD; Andrea Fava, MD; Cheri Frey, MD; Neda F. Gould, PhD; Nishant Gupta, MD; Sarthak Gupta, MD; Sarfaraz Hasni, MD; David Hunt, MD; Mariana J. Kaplan, MD; Alfred Kim, MD; Deborah Lyu Kim, DO; Rukmini Konatalapalli, MD; Fotios Koumpouras, MD; Vasileios C. Kyttaris, MD; Jerik Leung, MPH; Hector A. Medina, MD; Timothy Niewold, MD; Julie Nusbaum, MD; Ginette Okoye, MD; Sarah L. Patterson, MD; Ziv Paz, MD; Darryn Potosky, MD; Rachel C. Robbins, MD; Neha S. Shah, MD; Matthew A. Sherman, MD; Yevgeniy Sheyn, MD; Julia F. Simard, ScD; Jonathan Solomon, MD; Rodger Stitt, MD; George Stojan, MD; Sangeeta Sule, MD; Barbara Taylor, CPPM, CRHC; George Tsokos, MD; Ian Ward, MD; Emma Weeding, MD; Arthur Weinstein, MD; Sean A. Whelton, MD
The reason we mention this is to render it clear that this isn’t one man’s opinions (as happens with many books about certain topics), but rather, a panel of that many doctors all agreeing that this is correct and good, evidence-based, up-to-date (as of the publication of this latest revised edition) information.
Take care!
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