Mental Illnesses 101

Psychiatric illnesses are diseases of the brain, but so are neurological illnesses and delirium. Before we talk about what mental illness is, let’s briefly discuss what it isn’t. As with much in medicine, the lines between the categories of diseases are often gray and hazy, and this is particularly true when classifying diseases as “neurologic” or “psychiatric.”  Generally speaking, a neurologic illness is a brain disorder that is caused by an identifiable cause like an ischemic stroke (a plague blocking an artery that supplies the brain causing that part of the brain to die), an intracranial bleed, or a mass lesion like a tumor. There are also a plethora of diseases that historically have fallen under the realm of neurology even though the causative process isn’t as obvious as a dead portion of the brain, a giant blood clot in your noggin, or a tumor lunching on your noodle. These diseases include epilepsy, multiple sclerosis, and the dementias—the slow decline of cognitive abilities—the best known of which is Alzheimer’s disease. Finally, delirium—a rapid decline in mental status—is also exempted from the realm of psychiatry because most of the causes of delirium are readily identifiable and reversible (e.g. being intoxicated on a bunch of drugs, or being so sick with severe pneumonia that your brain checks out for a few days).

So that’s what mental illness isn’t. Now let’s briefly review the main categories of psychiatric disease and, hopefully, dispel some common misconceptions about them along the way.

Psychosis is a chronic disturbance of reality that often presents with auditory hallucinations (hearing voices) and with delusions—fixed false beliefs that persist even when the patient is presented with overwhelming evidence to the contrary. Delirium can present with hallucinations too, but the difference is that people with delirium become this way rapidly and then snap out of it once whatever is causing the delirium is fixed. Delirious people tend to be totally out of it—not oriented to person, place, or time. In contrast, psychosis is usually chronic, developing over time and presenting with someone who is alert and, relatively speaking, “with it.” Schizophrenia is the best known psychotic disorder and John Nash, the mathematician from the excellent movie, A Beautiful Mind, is an extremely high functioning schizophrenic.

Schizophrenia can be treated with antipsychotic medications; unfortunately, these medications tend to have really horrible side effects, including causing Parkinson’s Disease type movement disorders (shuffling gait, rigidity, “pill-rolling” tremors of the hands) and an involuntary movement disorder of the face that is called tardive dyskinesia. Interestingly, all antipsychotics exert their antipsychotic effects by blocking dopamine—people with Parkinson’s Disease have the opposite problem, not enough dopamine, and one of the primary treatments for that disease is with a dopaminergic medication called levodopa.

Bipolar Disorder is not “split” or “multiple personalities!” Bipolar disorder is a disease that is characterized by alternating between severe depression and mania. Mania is an extremely elevated mood that is closely akin to how people feel/look when they are high on cocaine or methamphetamine. Mania is characterized by the mnemonic “DIG FAST”—Distractibility; Irresponsible behaviors; delusions of Grandeur; Flight of ideas; increased Activity; decreased need for Sleep; and Talkativeness. A manic person is like Woody Woodpecker, bouncing all over the place and talking a million miles per hour! Mania causes people to do really stupid things, like blowing all their savings in one day or having sex with a dozen people that they’ve just met over the course of a week. In bipolar disorder, depression follows mania and the depression is often severe. These patients have a very high risk of committing suicide, as evidenced by Kurt Cobain, the lead singer of Nirvana, who suffered from bipolar disorder. Another famous person with bipolar disorder was Leonardo DaVinci, who lived into old age and died from natural causes with the King of France holding his hand in a gesture of support and respect for the great man.

Tomorrow we’ll discuss depression and the anxiety disorders. Thanks for visiting!

Dr. Leonardo Noto

Physician and Author of Medical School 101, Intrusive Memory, The Life of a Colonial Fugitive, and The Cannabinoid Hypothesis.

Author Bio: Dr. Leonardo Noto is the nom de plume of a former airborne battalion surgeon who is now in private practice. Dr. Noto is the author of four full-length works and he also writes for a medical education corporation that assists medical students, interns, and residents as they prepare for the medical board examinations. Dr. Noto is the proud father of an extremely spoiled 11-month-old American bulldog who enjoys slobbering and tearing up things that he is not supposed to. Dr. Noto is an amateur practitioner of muay Thai and Brazilian jiu jitsu and he is currently learning to play the guitar (but he is currently a quite terrible musician, as his neighbors will readily attest).

Remember to discuss all health concerns with your personal physician (I don’t count!). This blog is intended to present general medical information for entertainment purposes and not as a specific guideline to any medical treatment. The author has made every effort to present accurate information; however, due to the ever-changing nature of medicine and the intrinsic caveats that are inherent in any particular case, no medical decisions should ever be made based on information gleaned from the internet. The internet and self-education are great, but they don’t replace your doc!

Why We Can’t Cure or Prevent the Common Cold

Have you ever mused over the fact that humans have eradicated small pox, nearly wiped polio off the face of the map, and beaten countless other deadly pathogens into worldwide remission in spite of the fact that there is just about nothing that modern medicine can offer to treat, much less prevent, the common cold? Seriously, unless you’re chronically ill with a disabling disease (like cancer, for instance), the best that your physician can do to treat your once or twice yearly cold is to suggest the same things that you could have done for yourself— to take it easy for a few days, cover your mouth/wash your hands so that you don’t spread your pestilence, and drink plenty of fluids. So what gives? Why is there a vaccine for influenza, mumps, and measles but not one for the blasted virus that invariably shows up every year at the worst possible time–like right before you have to give that big presentation in front of your boss, for instance.

There are a few reasons that the common cold is so difficult to prevent via vaccination; in fact, it is impossible to prevent via vaccination at the present. For one thing, cold-like symptoms are caused by a plethora of different viruses and all of these viruses have several strains, each of which can get you sick. Take rhinovirus (Latin for “nose-virus”) as an example because it is the most common cause of the cold. There are at least 100 different strains of rhinovirus alone! Getting sick with one strain of rhinovirus protects you against getting sick from that strain again—but that leaves an awful lot of strains out there just waiting to inflict their misery at that inopportune time. To make matters worse, viruses mutate extremely rapidly, constantly evolving into new strains, many of which are capable of getting you sick all over again. So in order to make an effective vaccine for the common cold you would need to both protect against 100s of viruses and also to constantly update the vaccine to keep up with newly emerging variants of each strain—not a likely prospect in the near future.

The makers of the flu vaccine face these same problems, albeit on a much smaller scale. Influenza is constantly mutating; in fact, next year’s strain of influenza probably hasn’t even been “born” yet. Sometime over the next few months, flu viruses living in pigs, birds, or humans in Asia will swap genes with other strains of flu viruses that happen to be infecting the same unlucky host (fun: being sick with two strains of influenza simultaneously!) and a new virus will be born. Fortunately, since most new flu viruses are born in Asia, living in the Western hemisphere allows the vaccine makers the time to figure out which strain of flu is likely to march around the world and to make a vaccine in time (usually) to prevent a major outbreak—or at least that’s how it would work if people would get their flu shots! Even with influenza, vaccine development is a bit of a guessing game because it takes several months to develop and to manufacture each year’s vaccine—by the time we know for sure which flu virus is going to go globetrotting from Asia to the West it’s too late. The vaccine makers hedge their bets by incorporating the three most likely epidemic-causing flu strains into the yearly vaccine, and they’re usually right with one of them. Perhaps one day we’ll be able to do the same for the common cold, but I wouldn’t count on it in the near future—bed rest, plenty of fluids, cover your mouth, and wash your filthy hands remains the best advice for most people when it comes to the cold.

Factoid: Asia, especially Southeast Asia, has several flu epidemics every year–we’re lucky in the West that we’re far enough away from the region where most strains of flu are born that we only (usually) have one flu epidemic per year.

Dr. Leonardo Noto

Physician and Author of Medical School 101, Intrusive Memory, The Life of a Colonial Fugitive, and The Cannabinoid Hypothesis.

Author Bio: Dr. Leonardo Noto is the nom de plume of a former airborne battalion surgeon who is now in private practice. Dr. Noto is the author of four full-length works and he also writes for a medical education corporation that assists medical students, interns, and residents as they prepare for the medical board examinations. Dr. Noto is the proud father of an extremely spoiled 11-month-old American bulldog who enjoys slobbering and tearing up things that he is not supposed to. Dr. Noto is an amateur practitioner of muay Thai and Brazilian jiu jitsu and he is currently learning to play the guitar (but he is currently a quite terrible musician, as his neighbors will readily attest).

Remember to discuss all health concerns with your personal physician (I don’t count!). This blog is intended to present general medical information for entertainment purposes and not as a specific guideline to any medical treatment. The author has made every effort to present accurate information; however, due to the ever-changing nature of medicine and the intrinsic caveats that are inherent in any particular case, no medical decisions should ever be made based on information gleaned from the internet. The internet and self-education are great, but they don’t replace your doc!

Lymphoma 101

As I said in my previous blog post, the line between leukemia and lymphoma is thin and gray. Both leukemia and lymphoma are cancers of blood cells. Leukemia is usually a cancer of the bone marrow—the soft interior of the bones that make new blood cells—and leukemia also presents with cancerous cells floating around in the peripheral bloodstream, zipping around the body through every blood vessel, big and small, by the current that is produced by your beating heart. Lymphoma, on the other hand, classically presents as a solid mass of the lymphoid tissues. Lymphoid tissues, including lymph nodes, are scattered throughout most of your body and are essentially little filters that contain white blood cells and that help your body to fight off invaders like bacteria. Lymphoma occurs when white blood cells because cancerous (i.e. acquire mutations that allow them to grow uncontrolled) and the types of cancer that comprise lymphoma love to set up shop in the lymphoid tissues.

The most famous type of lymphoma is Hodgkin Lymphoma (aka: Hodgkin’s Disease). Hodgkin Lymphoma is a nasty cancer that most commonly inhabits the lymph nodes that line the borders of the heart and the middle of the chest cavity (the mediastinum). Hodgkin Lymphoma hits you like a semi-truck, causing “B Symptoms”—fever, drenching night sweats, and unexplained weight loss. Fortunately, medical advances over the past half-century have made Hodgkin Lymphoma a highly treatable disease and most patients respond well to chemotherapy, radiation therapy, or a combination of both.

Whereas Hodgkin Lymphoma is special and gets its own category, all of the rest of the lymphomas (and there are A LOT of them) get lumped together and are called “Non-Hodgkin Lymphoma” (“NHL”)—I don’t know about you, but if I were a type of NHL, I would think about suing for discrimination. A few of the most interesting NHLs include Burkitt’s Lymphoma, Mucosa-Associated Lymphoid Tissue Lymphoma (MALT Lymphoma), and Adult T cell Lymphoma. Burkitt Lymphoma is an endemic disease in Africa that is caused by the Epstein-Barr Virus—the same virus that causes mononucleosis (“mono;” the “kissing disease”). In Africa, Burkitt Lymphoma causes disfiguring facial masses with apical ulcerations in young children and it is truly an awful disease. Burkitt Lymphoma also occurs in a sporadic form in Western countries where, oddly, it tends to cause abdominal masses instead of facial lesions. MALT Lymphoma causes cancer of the lymphoid tissue in the gastrointestinal tract and it is caused by infection with the bacteria, H. pylori, that loves to live in our stomachs and which also causes ulcers in susceptible people. MALT Lymphoma is unique in that it is the only cancer that can be cured with antibiotics (using antibiotics to kill H. pylori)—it doesn’t always work, but it often does and when it does patients and doctors are both very happy! Adult T Cell Lymphoma is caused by infection with the Human T cell Lymphoma Virus, Subtype 1 (HTLV-1), and it usually kills within 6-12 months. Adult T Cell Lymphoma is capable of invading just about every tissue in the body, spreading to the skin, the internal organs, and the lymphoid tissues. This awful disease is most common in persons who also have AIDS (immunodeficiency that is caused by another virus, HIV—Human Immunodeficiency Virus).

Dr. Leonardo Noto

Physician and Author of Medical School 101, Intrusive Memory, The Life of a Colonial Fugitive, and The Cannabinoid Hypothesis.

Author Bio: Dr. Leonardo Noto is the nom de plume of a former airborne battalion surgeon who is now in private practice. Dr. Noto is the author of four full-length works and he also writes for a medical education corporation that assists medical students, interns, and residents as they prepare for the medical board examinations. Dr. Noto is the proud father of an extremely spoiled 11-month-old American bulldog who enjoys slobbering and tearing up things that he is not supposed to. Dr. Noto is an amateur practitioner of muay Thai and Brazilian jiu jitsu and he is currently learning to play the guitar (but he is currently a quite terrible musician, as his neighbors will readily attest).

Remember to discuss all health concerns with your personal physician (I don’t count!). This blog is intended to present general medical information for entertainment purposes and not as a specific guideline to any medical treatment. The author has made every effort to present accurate information; however, due to the ever-changing nature of medicine and the intrinsic caveats that are inherent in any particular case, no medical decisions should ever be made based on information gleaned from the internet. The internet and self-education are great, but they don’t replace your doc!

Leukemia Explained

Leukemia has recently been in the press due to the Manti Teo scandal (I have no idea if he was the victim or the perpetrator and I really don’t care, btw). Leukemia is a cancer of the blood and it is characterized by cancerous cells that grow like crazy in the bone marrow—the soft inner cavity of your bones—and then float around in the bloodstream to cause all sorts of mischief. Cancer, in general, is the uninhibited growth of a lineage of cells in your body. This is bad for some fairly obvious reasons—you wouldn’t want a second heart growing inside your brain or a bone growing inside of your liver. To prevent this your body has several control mechanisms that tell cells where to grow, when to grow, and when not to grow. In cancer, mutations (changes in DNA) cause certain cell lines to escape these controls and to grow unabated—in leukemia, the bad boy cells are blood cells.

There are five main types of leukemia: Acute Lymphoblastic Leukemia (ALL), Chronic Lymphoblastic Leukemia (CLL), Acute Myelogenous Leukemia (AML), Chronic Myelogenous Leukemia (CML), and Hairy Cell Leukemia (HCL). ALL is a cancer of the lymphocytes—the B cells that produce antibodies and/or the T cells that function both to directly kill bad cells (like bacteria) and as the “generals” of the immune system (T cells are also the cells that are dysfunctional in AIDS). ALL is a disease of children and adolescents and it presents with a high fever, bleeding, and bone pain due to the cancer expanding in the bone marrow. ALL is treated with chemotherapy or with a bone marrow transplant and, fortunately, it has a fairly good prognosis (about 85% of patients survive for at least 5 years—5 year survival rate is the standard by which response to chemotherapy is usually measured). CLL and HCL are also diseases of lymphoblasts but they are both indolent (slowly progressive) diseases that usually affect the elderly (median age = 65). AML, like ALL, is an acute leukemia—this means that it hits the patient hard and fast. AML is typically a cancer of adults and it is treated with chemotherapy. AML differs from ALL/CLL/HCL in that it is a cancer of myeloid cells (another type of white blood cells) instead of lymphoblasts. CML is also a cancer of myeloid cells and it usually affects people who are 40-60 years old. CML is a chronic cancer but it has a nasty tendency to transform into an acute form that is extremely deadly, especially if the patient doesn’t get treated when their CML is playing more nicely.

Lymphoma is a close relative of leukemia and the line between leukemia and lymphoma is actually quite thin and gray. Whereas leukemia classically is a cancer of the bone marrow and the bloodstream, lymphomas usually form masses in the body, especially in the lymph nodes that are found in just about every tissue from the abdomen, to the extremities, to the chest, to the head and neck. We’ll discuss lymphoma in greater detail next time—thanks for visiting!

Dr. Leonardo Noto

Physician and Author of Medical School 101, Intrusive Memory, The Life of a Colonial Fugitive, and The Cannabinoid Hypothesis.

Author Bio: Dr. Leonardo Noto is the nom de plume of a former airborne battalion surgeon who is now in private practice. Dr. Noto is the author of four full-length works and he also writes for a medical education entity that assists medical students, interns, and residents as they prepare for the medical board examinations. Dr. Noto is the proud father of an extremely spoiled 11-month-old American bulldog who enjoys slobbering and tearing up things that he is not supposed to. Dr. Noto is an amateur practitioner of muay Thai and Brazilian jiu jitsu and he is currently learning to play the guitar (but he is currently a quite terrible musician, as his neighbors will readily attest).

Remember to discuss all health concerns with your personal physician (I don’t count!). This blog is intended to present general medical information for entertainment purposes and not as a specific guideline to any medical treatment. The author has made every effort to present accurate information; however, due to the ever-changing nature of medicine and the intrinsic caveats that are inherent in any particular case, no medical decisions should ever be made based on information gleaned from the internet. The internet and self-education are great, but they don’t replace your doc!

The Medical Physiology of Gunshot Wounds

Unfortunately, gunshot wounds have been in the news lately and for some really terrible reasons. The key to understanding basic gunshot physiology can be boiled down to Newton’s second law of motion: Force = Mass x Acceleration. This little equation explains goes a long way in explaining why an M-16/M-4/AR-15 produces so much more damage than your standard .22 caliber hunting rifle in spite of the fact that the .22 and the M-4 both fire the same size bullet. In short, the M-4 fires that bullet with a much larger powder charge and, if we refer back to our equation, you can increase the force imparted by a bullet either by increasing the size of the bullet OR by increasing its acceleration (i.e. by increasing the amount of powder that you fire it with).

For most of history military muskets (smoothbore weapons) and rifles (weapons with grooved barrels to improve accuracy) fired huge bullets—in the .50 caliber or higher range. However, with the invention of multi-shot rifles and the evolution of the infantryman from a formation fighter, who fired en masse with the rest of his unit, into a more or less autonomous warrior, military engineers realized that it was becoming ever more important on the battlefield for soldiers to carry a lot of bullets. This presented a problem because walking around with sacks of giant lead bullets slows you down because lead is heavy, limiting the amount of ammunition that a soldier could reasonably carry. Their solution was to design rifles that fired small bullets at a very high muzzle velocity, allowing for high capacity magazines that were both lightweight and which still fired ammunition that packed lots of punch (force).

A bullet has two major effects when it hits a person—the permanent cavity and the temporary cavity. The permanent cavity is the actual hole that the bullet punches out when it travels from one side of the body to the other while the temporary cavity is a shockwave that ripples out from the permanent cavity, briefly causing a much larger hole in the body then the one that is caused by the mechanical trauma of the bullet. Depending on where the bullet impacts the human body, the temporary cavity can either be a not very big deal (it is called “temporary,” right) or a really huge problem. Bullets that strike highly compliant tissues, like a bullet that travels through your biceps for instance, do most of their damage with the primary cavity whereas a bullet that lands next to a noncompliant critical structure, like the aorta (the largest artery in the body) can kill you with the temporary cavity even if the actual path of the bullet (the permanent cavity) doesn’t hit a critical structure. A shockwave that causes the aorta to rupture is just as fatal as a bullet that actually passes through this artery—you’re dead in a matter of seconds.

Now for the caveats, the first and foremost of which is tumbling. Firing bullets at a very high velocity often results in the tumbling of the round in the human body and can also result in the fracturing of the bullet into several pieces, all of which do a huge amount of damage. The round that is fired by the M16/M4 is specifically designed to have both of these effects. The round first tumbles at about 10cm of penetration, resulting in a greatly enlarged permanent and temporary cavity since the bullet is now traveling through the body sideways and head-over-heels. The round is also grooved around the mid-section and this results in the fragmentation of the bullet a few centimeters after it begins tumbling—the effect is to produce several permanent cavities instead of just one. Finally, although illegal on the battlefield and not fired by the military, hollow-tipped bullets are a common modification that also results in a much larger permanent cavity than you would expect based on the size of the round being fired. Hollow-tipped bullets flatten when they impact tissue, resulting in a much wider bullet traveling through the body than the one that exited the gun.

Dr. Leonardo Noto

Physician and Author of Medical School 101, Intrusive Memory, The Life of a Colonial Fugitive, and The Cannabinoid Hypothesis.

Author Bio: Dr. Leonardo Noto is the nom de plume of a former airborne battalion surgeon who is now in private practice. Dr. Noto is the author of four full-length works and he also writes for a medical education entity that assists medical students, interns, and residents as they prepare for the medical board examinations. Dr. Noto is the proud father of an extremely spoiled 11-month-old American bulldog who enjoys slobbering and tearing up things that he is not supposed to. Dr. Noto is an amateur practitioner of muay Thai and Brazilian jiu jitsu and he is currently learning to play the guitar (but he is currently a quite terrible musician, as his neighbors will readily attest).

Remember to discuss all health concerns with your personal physician (I don’t count!). This blog is intended to present general medical information for entertainment purposes and not as a specific guideline to any medical treatment. The author has made every effort to present accurate information; however, due to the ever-changing nature of medicine and the intrinsic caveats that are inherent in any particular case, no medical decisions should ever be made based on information gleaned from the internet. The internet and self-education are great, but they don’t replace your doc!

The Medical Physiology of Brazilian Jiu Jitsu Submissions

I’m in the mood to have a little bit of fun for the weekend, and fun to me means either spending time with my dog or spending some time on the jiu jitsu mats! For the uninitiated, Brazilian jiu jitsu is an advanced form of Japanese jiu jitsu that was developed by the Gracie family in Brazil during the early 20th century, especially by Helio and Carlos Gracie. Helio was a 140lb little guy who routinely fought in no holds barred, full contact fights in Brazil against opponents who usually were twice his size, winning every fight during his long career save one. Helio’s son later went on to become the Champion of the first 4 Ultimate Fighting Championships (UFC) in spite of the fact that he only weighed 175lbs and that many of his opponents topped the scales in the high 200s, the 300s, and even the 400lb range! Brazilian jiu jitsu is essentially the art of using chokes and joint locks to enable a smaller person to defend themselves against a much larger opponent—here’s how it works. Before I explain this stuff, you obviously should not try any of this at home, or anywhere else for that matter, without the supervision of someone who knows what the heck they are doing (e.g. a Brazilian jiu jitsu instructor)—many of these techniques are potentially fatal if not performed by a skilled practitioner.

The most famous chokes in Brazilian jiu jitsu are the rear naked choke and the triangle choke. The rear naked choke is performed by getting behind your opponent and wrapping your arm around their neck so that their trachea (windpipe) rests in the crook of your elbow. Using your other arm as a brace and as a fulcrum, the choking arm is then closed around your opponents neck, using the forearm and the biceps to squeeze both sides of the neck, resulting in the rapid unconsciousness (and if not quickly released, death) of your opponent. This choke is a “blood choke” and it works by compressing the carotid artery that is located on either side of the neck. The carotid artery is responsible for ~80% of blood flow to the brain and, because the brain has an extremely high metabolism (metabolism shuts down without oxygen, which is carried in blood), it calls it quits after 10-15 seconds of choking and unconsciousness is the result. A brain that is deprived of blood for greater than about 4 minutes suffers irreparable damage so this choke is rapidly let go in a training environment—in a street fight it is deadly, and easily so. The triangle choke is performed similarly but instead of squeezing both sides of the opponents neck with your arm the jiu jitsu practitioner instead use their leg to squeeze one side and their opponents trapped arm to squeeze the other side. This technique is performed from your back (your “guard”) and, although difficult to learn initially, is easily performed by a trained practitioner of jiu jitsu and it is one of the most common submissions in competitive mixed martial arts.

The other form of choke is the “air choke,” a choke that is performed by directly crushing the windpipe. Unlike the blood choke, which can be safely performed in training by people who know what they’re doing, the air choke is very likely to cause severe damage to the trachea which may necessitate a trip to the emergency room or the morgue. The simplest way air choke is performed by ramming the outer bone of the forearm, the ulna, down onto your opponents neck—this technique is primarily used in extreme self-defense or combat situations and, if I haven’t said it enough, should not be tried at home!

Joint locks are probably the most common form of submission by grapplers in both grappling competitions and in mixed martial arts fights. Joint locks, like arm bars and knee bars, are obviously painful but they are also potentially fatal for reasons that aren’t quite as obvious. The knee bar is the best example, as I’ll explain, but this holds true for the arm bar as well. A knee bar is performed by wrapping yourself around that front of your opponent’s leg and then forcibly straightening the knee joint until it is locked. Pressure is then applied to the joint to straighten it farther than it is naturally supposed to go, resulting in pain. Now it doesn’t take a genius to figure out that you could break someone’s leg this way, and since a proper knee bar places all of your body weight on top of the person’s leg it also is fairly evident that this isn’t a very difficult thing to do if you really needed to to defend yourself. However, what isn’t so obvious is that a huge artery, the popliteal artery that supplies your lower leg, lies directly behind the knee joint and if the knee joint is broken the popliteal artery is likely to rip as well, leading to massive blood loss. Arm bars are similar because the brachial artery, which also is fairly large, is located just over the elbow joint and an elbow that gets bent the wrong way (i.e. broken) can tear this artery to shreds. And one final time because there is no shortage of idiocy in the world—do not try any of these techniques at home!!! If you want to learn how to grapple for self defense, go join a jiu jitsu gym, which is also a great way to get into shape and to build self-confidence and self-esteem!

Dr. Leonardo Noto

Physician and Author of Medical School 101, Intrusive Memory, The Life of a Colonial Fugitive, and The Cannabinoid Hypothesis.

Author Bio: Dr. Leonardo Noto is the nom de plume of a former airborne battalion surgeon who is now in private practice. Dr. Noto is the author of four full-length works and he also writes for a medical education entity that assists medical students, interns, and residents as they prepare for the medical board examinations. Dr. Noto is the proud father of an extremely spoiled 11-month-old American bulldog who enjoys slobbering and tearing up things that he is not supposed to. Dr. Noto is an amateur practitioner of muay Thai and Brazilian jiu jitsu and he is currently learning to play the guitar (but he is currently a quite terrible musician, as his neighbors will readily attest).

Remember to discuss all health concerns with your personal physician (I don’t count!). This blog is intended to present general medical information for entertainment purposes and not as a specific guideline to any medical treatment. The author has made every effort to present accurate information; however, due to the ever-changing nature of medicine and the intrinsic caveats that are inherent in any particular case, no medical decisions should ever be made based on information gleaned from the internet. The internet and self-education are great, but they don’t replace your doc!

Radiology 101 Continued — MRI and Radionuclide Studies

Radiology 101 Continued — MRI and Radionuclide Studies

The way that magnetic resonance imaging, or “MRI” for short, got its name has as much to do with psychology as it does with radiology. Not surprisingly, magnetic resonance imaging is based on magnetic fields (you don’t say!). The MRI technique was perfected by organic chemists and its real name is nuclear magnetic resonance imaging (NMR); however, because the term “nuclear” scared the heck out of people during the Cold War, the good old days when the threat of nuclear annihilation was on the news every other night, physicians decided to go with the more politically correct term MRI instead. A really powerful magnet—so powerful that they have killed people when oxygen tanks and other heavy metal objects were unfortunately carried too close to the MRI machine—induces the nuclei of the atoms in your body to all spin in the same direction. This uniform spin, as opposed to the naturally more chaotic arrangement, is at a higher energy state and the atoms begin to return to their ground state (a naturally lower energy state/spin) as soon as the magnetic force is removed—don’t let me scare you with the physics here, I’m about to explain all of this in English. When the atoms in your body return to their ground state they emit energy, the energy that the magnetic force imparted upon them before we turned it off, and this energy is detected by the MRI machine. Specifically, an MRI is calibrated to detect the energy given off by the hydrogen atoms in water molecules as they return to their ground state. Since the concentration of water differs from body tissue to body tissue, this allows extremely detailed imaging of your insides.

One notable side effect that NMR/MRI does NOT have is the danger of being exposed to radioactivity—the dangerous energy that is emitted by some nuclear processes (processes involving the nucleus of atoms), including the processes used by X-ray and CT scan. The “nuclear” in NMR/MRI here simply refers to the use of a big ole magnet to change the way the nucleus is spinning (like spinning a top or a dradle in the other direction) and there is no dangerous radioactive energy involved. With that said, MRI definitely does have its drawbacks. For one, large metal objects that get to close to the machine can (and have) become deadly projectiles and metal shards in the eyes of people who work with sheet metal without eye protection (a bad idea) can move around and damage the retina, potentially causing blindness. MRI can also interfere with the function of some really important implantable medical devices including pacemakers and automated internal defibrillators. MRI also takes a really long time, is super expensive, is performed in a claustrophobic cylinder, and is so noisy that you have to wear ear plugs during the procedure—these can be major issues for young children and for people who are claustrophobic or who do not have health insurance. So MRI has a lot of really big drawbacks, but its upside is that in most instances it produces the best medical imaging that currently exists—the images can be so lifelike that they more or less look exactly like a dissected cadaver or a body that is cut open on the operating table (and I know because I’ve dissected two complete cadavers in my life and I’ve been present for a lot of surgeries).

Radionuclide imaging is our last stop on this tour of the world of medical imaging. In a nutshell, a substance that is naturally present in the body and that is naturally taken up by your cells (e.g. the sugar glucose) is labeled with a small amount of a radioactive isotope. The radiation that is given off by the radiolabeled substance is transmitted out of the body to a detector, a really useful technique for getting functional images of the body. Functional images? Yes, because cells that are more metabolically active (like cancer cells, for instance) take up more glucose, including more radiolabeled glucose, and then emit a stronger signal, telling the radiologist exactly where the tumor is, even if it is too small to be seen with more conventional imaging techniques. A similar procedure uses radioactive phosphorus to detect small fractures in the bones, a technique that works really well because bones are primarily composed of calcium and phosphorus and they contain a much greater amount of phosphorus (and thus take up more of the radioactive phosphorus) than other tissues. Because the body is working overtime to heal fractures, the areas of the bones that are fractured will take up an even greater amount of the radioactive phosphorus than the surrounding, healthy bone.

Radionuclide imaging sounds scary but the amount of radioactive energy that you are exposed to during these procedures is actually quite small, about the same amount as you are exposed to during a single X-ray and a whole, whole lot less than the amount of radiation that your body gets blasted with during a CT scan. The downside of radionuclide imaging is that its images are fuzzy and generally only useful for a few highly specialized procedures, like the ones that I described above, and not very useful most of the time.

Thanks for visiting! I hope that you’ve enjoyed my blog and that I’ll see you again soon!

Dr. Leonardo Noto

Physician and Author of Medical School 101, Intrusive Memory, The Life of a Colonial Fugitive, and The Cannabinoid Hypothesis.

Author Bio: Dr. Leonardo Noto is the nom de plume of a former airborne battalion surgeon who is now in private practice. Dr. Noto is the author of four full-length works and he also writes for a medical education entity that assists medical students, interns, and residents as they prepare for the medical board examinations. Dr. Noto is the proud father of an extremely spoiled 11-month-old American bulldog who enjoys slobbering and tearing up things that he is not supposed to. Dr. Noto is an amateur practitioner of muay Thai and Brazilian jiu jitsu and he is currently learning to play the guitar (but he is currently a quite terrible musician, as his neighbors will readily attest).

Remember to discuss all health concerns with your personal physician (I don’t count!). This blog is intended to present general medical information for entertainment purposes and not as a specific guideline to any medical treatment. The author has made every effort to present accurate information; however, due to the ever-changing nature of medicine and the intrinsic caveats that are inherent in any particular case, no medical decisions should ever be made based on information gleaned from the internet. The internet and self-education are great, but they don’t replace your doc!