Saturday, March 29, 2014

WILTIMS #129: Doctor, it hertz!

Today was the last day before - you guessed it! - our first round of exams for this, the last block of first year. On Monday we have two exams that I am not looking forward to. At some point this weekend I need to memorize 48 medications, their mode of action, and side effects, and that's just for the Behavioral Sciences exam, supposedly the disproportionately easy class of the block. See you on the other side.

TIL: Tremors can be differentiated by their frequency. A 6-12 hertz vibration is typical of a stress-induced "physiological" tremor, whereas a slower 4 hz is indicative of Parkinson's.

Friday, March 28, 2014

WILTIMS #128: Wombesque

TIL: The term hysteria originated back in Hippocratic times and comes from the belief that hysteria was an exclusively female disorder caused by the movement of uterus within the body (hence it shares the same root with hysterectomy). This unfounded association lasted for centuries and resulting in some bizarre treatment ideas. An older idea was to put nasty things in the mouth of the patient and flowers or perfumes around the vagina to - I kid you not - try to lure the uterus back into position when it had wandered elsewhere in the torso. More recently, hysteria was treated by orgasm. As documented in the 2011 film Hysteria, the first vibrator was invented to treat women with this disorder.

The term hysteria is no longer used clinically in medicine, having been replaced by the broad category of somatization disorders or, more acutely, conversion disorder.

So remember, if you call a joke hysterical, you're really saying it's... womb-y.

Thursday, March 27, 2014

WILTIMS #127: Om nom nom!

TIL: Apparently part of Pixar's Ratatouille is more lifelike than I had originally believed. Supposedly rat colonies actually have "taster rats" that have extra-sensitive taste receptors to detect poison. If the taster rat hesitates or gets sick, the rest of the colony will avoid the food stash. I love this anecdote and it did come from an expert on taste, but I can't find any reputable source on the internet, so take it with a grain of salt. See what I did there?

When you eat something spicy, you tear-up in an effort to dilute the food in your stomach. As you may remember from Anatomy, tears are produced in glands in the upper outside corner of each eye and drain in a canal by the nose into the nasal cavity. If you sniff rather than blow your nose, the tears will flow back down your throat into your stomach. Along with increased salivation and mucous secretion this dilutes the spicy food, lessening any damage to the rest of the digestive tract.

Babies can taste what the mother eats in her milk and have been shown to prefer those foods later in life. But babies also have more taste receptors than adults, so it is nice to scale down the extreme tastes or the baby may have trouble breastfeeding. Perhaps when nursing, go for a spiciness of 2 for your Thai curry instead of the sinus-clearing 4.

How to eat chocolate (I learned it in a med school lecture, so it's legit):
  1. Make sure it's dark.
  2. Make sure it is brittle.
  3. Appreciate the smell.
  4. Enjoy the feel in your mouth
  5. Enjoy the tastes and flavor.
Taste and flavor are not the same thing. A taste is one of the five qualities discerned through our sense of gustation (...taste). Flavor is the complex integration of taste, smell and memory that your brain associates with the ingestion of a food or drink.

A middle ear infection can cause a temporary loss of taste because some of the taste information from the tongue shares a cranial nerve with the middle ear en route to the brain.

Wednesday, March 26, 2014

WILTIMS #126: Poke

Sorry, but there wasn't much in the way of variety or terribly interesting information today. That being said, it is funny that looking back on the day, I disregarded each scheduled event in turn: boring class on US health care history, overwhelming class on psychiatric medications, and neuroanatomy lab playing around with human brains. That the last one has become tediously commonplace is pretty remarkable. I was poking a brain today and it was no big deal.

I promise not to become totally jaded, but as I naturally become desensitized, it takes a little more effort to see the craziness of the crazy things we do on a daily basis. Feel free to remind me to geek out on occasion.

TIL: Imipramine, a tricyclic antidepressant, is also indicated for use as a treatment for bed-wetting (or nocturnal enuresis if you want to sound fancy).

Tuesday, March 25, 2014

WILTIMS #125: Shadows and a shadowy circle

Doing a lecture on cognitive tests in front of medicals students is rather amusing. Everyone is trying to prove how smart they are. We know. You're smart. We all are. We're in med school. That didn't stop everyone (embarrassingly, myself included) from trying to repeat back 9 random digits or reorder a collection of letters and numbers. I guess it should comfort you that your future doctors are in fact above average at simple memory tests.

Quote of the Day: "If you can transplant it, it's probably not that important. " ~Neurosurgeon

TIL: The penumbra is the area around an ischemic stroke that has lost blood flow and become hypoxic but hasn't died. If the stroke is treated quickly, this tissue can still be saved. If you happen to be an astronomy buff, you will recognize the word penumbra from eclipses. For example, the umbra (shadow in Latin) is the area where the moon casts its shadow on the earth during a full lunar eclipse, completely blocking out the sun. The penumbra is the area where the moon is only blocking part of the sun, or a partial eclipse. Penumbra in neurology comes from the same root because it shows up as a "shadow" on x-ray film.

A useful way of remembering what shows up as white on a head CT (at least in urban areas): bone, blood, and bullets.

The Circle of Willis is a ring of anastamoses in the brain consisting of the anterior cerebral arteries, anterior communicating artery, internal carotid arteries, posterior cerebral arteries, posterior communicating arteries, but usually not (depending on the source) the basilar artery and middle cerebral arteries. It's all rather confusing because the loop of communicating arteries is fed by other arteries that you may or may not consider part of the circle itself.

Saturday, March 22, 2014

WILTIMS #124: T-3 years until Match Day

As you may have seen on the internet or news, today was Match Day for fourth year medical students around the country. The Match is the almost dystopian system used to pair graduating medical students with hospitals for residency programs. The whole process is completed by a computer algorithm that finds the best fit between the 35,000 applicants and 30,000 positions based off of ranked lists submitted by both students and hospitals. If you read those numbers correctly, you'll note that not everyone matches, though 94% of US allopathic seniors do (international and osteopathic schools generally don't fare as well).

A week before Match Day, emails go out to all applicants telling them whether they matched and, if they did, not saying where. Then on Match Day, all the matched seniors across the country meet at their schools and, at the stroke of noon eastern time, simultaneously open envelopes that tell them where they will spend the next 3-7 years of their lives.

Here are a couple videos showing the typical level of excitement:

My first-year class had lecture from 9-noon, so we got out of class right after the fourth-years had opened their letters. It was really exciting. Everyone was hugging and laughing and sharing tears of joy. They don't graduate or become doctors for another few months but Match Day is the real finale of medical school - the culmination of 3½ years of hard work (not to mention the years before that working to just get in!).

3 more years!

TIL: The first hospitals were developed as a place to treat travelers or pilgrims who couldn't be treated at home. Hospital, hostel, and hotel as share the same root.

Medical school admissions interviews and photos were first implemented at the University of Michigan to screen out Jewish and black applicants who were not otherwise identifiable by name.

Myelomeningocele, also known as spina bifida overta (or just spina bifida to the general public), causes hydrocephalus in 80% of babies. Spina bifida is a condition where a portion of the lower spinal cord doesn't form correctly and leaks cerebral spinal fluid (CSF) into the open air. This is incredibly dangerous because if, left untreated, the child will develop fatal meningitis within days. But once the hole is surgically sealed, the CSF starts building up in the brain because the normal draining routes never formed. Excess CSF fluid is called hydrocephalus and it requires the surgical implantation of a shunt that connects the CSF cisterns of the brain to the peritoneal cavity of the abdomen, where the fluid is easily absorbed.

Type I Chiari malformation is when the cerebellar tonsils block the foramen magnum (the hole in the skull through with the spinal cord passes), blocking CSF circulation and pinching the brain stem.

Dandy-Walker syndrome results from a malformation cerebellum and enlargement of the fourth ventricle.

Alobar holoprosencephaly is an often fatal deformation of the brain where the two hemispheres never develop.

Friday, March 21, 2014

WILTIMS #123: Oh, behave! (-ioral science)

Today I had my first behavioral science case conference and it was one of the most captivating experiences I have had yet in med school. A quarter of our class (about 50 students) decked out in our white coats filed into a small room in the behavioral health center at the nearby hospital and watched our professor interview an actual psychiatric patient. I won't share any specifics due to patient confidentiality but I think we were all surprised by the level of delusion we witnessed today.

Some thoughts from that session:
  • When interviewing a possibly psychotic patient you must always remain calm and understanding. The patient will be watching to see if you can handle the story they're telling before they are willing to reveal everything.
  • When appropriate, only challenge the delusion once - just to see how solid it is. Then back off and regain the patient's trust. Challenge in this case means merely asking if the patient has ever doubted that the delusion is real - not yelling at them or anything truly confrontational.
  • You must be careful about your emotions when dealing with medication non-compliance. Whereas it might be frustrating with other more physical medical problems, remember that non-compliance is actually part of the illness with psychiatric disorders.

TIL: Deer Hunter is a messed up movie. I'm pretty sure our professor wanted to teach us about PTSD by giving us PTSD using the most disturbing parts of this movie.

If a person with depression has one manic episode ever, then they are diagnosed as having a bipolar disorder.

Generally, bipolar patients who are undergoing treatment maintain the same level of symptoms throughout their lives while schizophrenic patients progressively decline.

1 in 7 people with untreated depression and 1 in 5 with untreated bipolar disorder will die from suicide. There is an emphasis on untreated here, but these numbers are still frighteningly high.

Thursday, March 20, 2014

WILTIMS #122: Glass half-full... vertically

Medical students are often equipped with two tuning forks. One tests hearing at a certain frequency and the other tests the sensation of vibration on the skin. This latter might seem a bit unusual; wouldn't a prod with a finger do just as well for testing the sense of touch? You need to test both, actually. "Crude" touch and vibrational touch are relayed to the brain via two different paths in the spinal cord, the spinothalamic tract and dorsal column respectively. A deficit in either is an important diagnostic sign of damage to the nervous system.

Example drawings from a patient with
contralateral neglect syndrome
TIL: The evolutionary age of the brain can be determined by the number of cell layers. The neocortex is the most recent to evolve with six layers. The archicortex of the hippocampus has only four layers and the paleocortex only three. Accordingly, the neocortex is only found in higher mammals while the archi- and paleocortices are also present in more primitive animals.

If you damage the visual association areas of the brain you can have a deficit whereby you can't recognize the things you see.

If you damage the somesthetic association area you can have a deficit where you literally ignore anything on one side of your vision. It's not that you can't see it or that you don't know what it is, but that you cannot focus your attention on it. This works for body parts too. You might see that your left arm is there but you think it's not your problem, as if it were someone else's arm.

Wednesday, March 19, 2014

WILTIMS #121: Left at Albuquerque

TIL: As per the Director of Undergraduate Medical Education in Psychiatry, "NOS means we don't know what the hell it is." More specifically, NOS stands for "not otherwise specified."

When choosing an initial pharmacological treatment for psychotic disorders you don't choose based on the drugs' respective efficacy but by the side effect profile of the patient. In other words, most of the drugs work equally as well so worrying about the potential side effects is more important.

The third ventricle of the brain is bordered laterally by the thalamus and hypothalamus, anteriorly by the lamina terminalis and anterior commissure, posteriorly by the pineal body and posterior commissure, superiorly by the fornix and coroid plexus, and inferiorly by the optic chiasm, pituitary infundibulum, tuber cinereum, and additional hypothalamus.

Tuesday, March 18, 2014

WILTIMS #120: They did what now?

A page from "The Anatomical Basis of
Medical Practice" (red added by me)
One of the fun quirks of the neuro block is that we get frequent guest lectures by neurosurgeons. This is a rarefied group of lecturers than solicit the attention of medical students faster than a drill sergeant at basic training. They are psychotically confident, they always have the most ridiculous videos, and they only present the positive-outcome cases so they seem like heroes. That said, after watching them in the neurosurgery conferences a few times, I think being half an auditorium away is probably the best distance.

TIL: An anatomy book was released in 1971 that used Playboy-style pictures of women to show surface anatomy. It was so offensive that I honestly could have believed that our chancellor was just messing with us. The authors were doctors at Duke that wanted to make anatomy more approachable... and since most med students at the time were men they thought misogynistic writing and salacious pictures would be an improvement. Thankfully it did not get a second printing.

Friday, March 14, 2014

WILTIMS #119: Penny for your thoughts

TIL: Stereognosis is the ability to perceive a three dimensional object by touch, without the aid of the other senses.

Postage stamps in England do not specify what country they are from. This may seem like an unusual fact to pick up in medical school but, as usual for our history of medicine lectures, it was in service of a larger and more pertinent point. The topic of stamps came up while examining a stampless letter from 1840s Mississippi. The letter was a bill for services done by a doctor for the property of a plantation owner.

Our chancellor has taken pains to avoid teaching only the history of the white male heroes of medicine. Some of this profession's history is less heroic than we'd like to remember, and we should try to learn from the failings of our past to minimize their inevitable repetition in the future. The example at hand was of the role doctors played in the slave trade and slavery in the American South. It is an example of the phrase made famous by Hannah Arendt when describing lower level Nazi administrators: the banality of evil. The majority of evil done in the world is not done by sociopathic masterminds, but by normal people just doing their job and perpetuating the status quo.

But what can a doctor do to protest? We have (or will have) taken an oath to treat the sick. To refuse to work for slaveholders is to damn the slaves to pain and death, but keeping the slaves healthy allows the system to continue. How is this relevant to us today? Doctors stand on the sidelines of every football game, giving players and fans a sense of security that everyone will be ok, because there are medical staff around. But studies keep showing that football does irreparable damage to nearly everyone who plays. Is the medical profession allowing an unethically dangerous activity to go on out of tradition?*

I welcome your thoughts! Feel free to comment below.

*I have a rebuttal to the argument that football is a choice, but don't feel like getting into it tonight, but comment and I will.

WILTIMS #118: Olive anyone?

What do pyramids and olives have in common? They are both the actual anatomical terms for features of the medullary region of the brain stem. There was a good 30 seconds that I thought our professor was just messing with us regarding the "olives."

TIL: Schizophrenia sucks. I kinda figured this already, but now I'm more confident. Not knowing what is real or only in your mind would be truly maddening.

The two hemispheres of the brain are connected in four places: the anterior commissure, the corpus callosum, the commissure of fornix and the posterior commissure.

The tectum of the mesencephalon (midbrain) is also known as the quadrigeminal plate. Quadri- for 4 and -geminal for twins, which discribes the two pairs of lumps featured on its surface.

Thursday, March 13, 2014

WILTIMS #117: When life give you dilemmas, make dilemonade!

Today we had 3 hours of neuro, two hours of FCM and two hours of medical ethics. Ethics was definitely the highlight. We had wonderful, intelligent and lively discussions on a whole array of ethical subjects. Throughout the course each student had to take a turn leading the small group through a case study. Today was my day and the topic was fascinating.

I discussed the surprisingly common practice of medical students performing unconsented pelvic exams on anesthetized hysterectomy patients. We discussed the many ways this could be considered unethical, even under the implicit consent of being treated in a teaching hospital. I then brought up other similar scenarios to see if there were situations where unconsented med student involvement could be ethical. If it was an exam of an ear instead of a vagina, people's feelings were more mixed. In another example, we mostly agreed that if a once-in-a-lifetime opportunity to observe a finding unexpectedly presented itself after the patient had already been knocked out, then bringing more people into the room than was consented would be ethical because the benefit to the education of students (and the future good of their patients) would trump the patient's rights, though the situation would have to be explained to the patient afterward. But that the students would merely be observing was a key point in this case.
The SNARE complex: Botox attacks the
BoNT sites while Tetanus targets TeNT

TIL: Botox, short for botulinum toxin, paralyzes muscles by cleaving the SNARE complexes that are responsible for binding of neurotransmitter-containing synaptic vesicles to the synaptic cleft.

Tetanus toxin works similarly but is only effective on inhibitory synapses. When these are deactivated, muscles are allowed to contract continuously. This is why tetanus is also known as lockjaw; early tetanus infection can cause people to uncontrollably clench their jaw. If left untreated, a common outcome is a broken back from all the back muscles contracting simultaneously. Get your tetanus booster shots!

Wednesday, March 12, 2014

WILTIMS #116: Cheers!

Today was rather mellow since I was in the lucky quarter of the class that had no lab or clinical session this afternoon. So, to supplement my musings for today, I have a couple of overflow points from yesterday's post.

Yesterday I went out with members of the Policy and a Pint club. As the name implies, this is a group that goes out to a local pub and discusses medical policy. The topic yesterday was single-payer and socialized medicine as compared to the US health care system, pre- and post-Obamacare. It was a smallish group this week, but we even had a resident Canadian to weight in. It is one of the highlights of attending medical school that I am surrounded with intelligent, concerned citizens who can respectfully discuss contentious issues and choose to do so at their leisure. Also, free beer.

Secondly, yesterday's topic in History of Medicine was on the role of the marginalized in medical education. Though I presented lots of fun tidbits, I never really broached the bigger point. In all of history, the ability for medical students to learn has been reliant on the bodies of the poor, lower class and subservient peoples. Gladiators were the subjects of Galen; murderers were the cadavers of Harvey; slaves were bought on their deathbeds for dissection in early southern medical schools.

Though we'd like to think that this trend ended alongside the slavery and indentured servitude that enabled it, that would be wishful thinking. My medical school has two major teaching hospitals, a large private hospital in the suburbs and a large urban public one in the city. As is common all over the country, teaching opportunities are fewer in the affluent and correspondingly litigious private hospitals. Thus the best learning experiences are often found at the grimy public hospitals, where the patients are overwhelmingly poor and of minority ethnicities. We still exploit the exploitable in order to learn and we have a ways to go before we fix this inequality.

TIL: If you use the phrases "touch yourself" and "make it rigid" in any context, you will overwhelm even the best resistance to juvenile humor.

You cannot have a diagnosis without impairment. Hearing voices is not a disease unless it causes dis-ease.

Tuesday, March 11, 2014

WILTIMS #115: The triumphant return

Against all odds, I have survived the second block of medical school! Whereas that block was supposed to be the hardest of first year, this next one is supposed to contain the hardest individual class: neuroscience. Fear for my worn out brain aside, I'm excited to get back into the anatomy lab to look at some other brains.

TIL: For hundreds of years, medical students had to rob graves in order to have bodies to dissect. They were called resurrectionists and would go out on - I kid you not - dark and stormy nights in the fall when the ground is still moist and easier to dig. Creepy Halloween story much? Kids were even warned about the "night doctor" who would snatch them off the street to dissect them if they weren't home on time.

In 1788, medical students from Columbia were confronted by an angry mob for dissecting a white woman. The color and gender is important, because no one had a problem with people dissecting black slaves or white male murderers. The governor called in the local militia to protect the anatomists but they wouldn't fight their fellow New Yorkers, so the upstate militia was called in. This was the first major riot in the fledgling United States.

The oldest medical building in the US at the University at Maryland and is built like a labyrinth to keep riot mobs from easily finding the anatomy lab.

In 1989, the University of Georgia started renovating its old medical school building and had to have the anthropology department excavate the bones of dozens of stolen dissection bodies from the dirt floor of the basement.

The Wellcome Museum of Anatomy and Pathology in London is only open to physicians and medical students (and other allied health professionals).