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According to my Facebook friends, the world is ending yet again. A few months ago it was Jew-hatred, inspired by the Trumpenfuhrer (see “Donald Trump is threatening Jews?“) and manifested as phone calls to Jewish schools and community centers. Now that the perpetrators turn out to have been an Israeli Jew with an autodialer and an anti-Trump journalist here in the U.S., my friends have been posting like crazy about the dire planet-melting consequences of an American withdrawal from the Paris climate agreement. Here are some samples of their posts and shared posts:

As a parent, as a global citizen, as a human being, as a life form sharing this planet, I cannot fully describe how upset I will be if our ignorance-pandering President does what he is apparently likely to do and exits the most promising global compact of any sort in recent years.

Ugh. Ashamed of my country that made such blind idiocy possible.

Jackass. Pulling out: idiotic. Toying with it arrogantly, omnipotently, to keep the world in suspense: disgusting.

Be there if you can to protest should Trump make good on his reckless promise to pull the United States out of the Paris climate accord. The rest of the world is aghast. This is no longer just about us or about stupid Trump voters — this decision affects the entire planet. [Regarding an Emergency Rally at the White House.]

I’m embarrassed to admit that, though perhaps I once did know what this agreement was (and in 2015 even asked about it here, with Dumb climate change agreement question: how is it different than a diet pledge?), I’d completely forgotten about it until this Facebook frenzy. I’m trying to reeducate myself on what friends tell me (shout at me, actually) is an item of cataclysmic importance to the planet’s future. So far I’ve read “Q. & A.: The Paris Climate Accord” (nytimes):

Unlike its predecessor treaty, the Kyoto Protocol, the Paris deal was intended to be nonbinding, so that countries could tailor their climate plans to their domestic situations and alter them as circumstances changed. There are no penalties for falling short of declared targets. The hope was that, through peer pressure and diplomacy, these policies would be strengthened over time.

So this is like my daily visits to the gym that I conduct annually? And my strict all-organic steamed vegetable diet that I alter as circumstances change, e.g., when bacon is available?

While the current pledges would not prevent global temperatures from rising more than 2 degrees Celsius above preindustrial levels, the threshold deemed unacceptably risky, there is some evidence that the Paris deal’s “soft diplomacy” is nudging countries toward greater action.

Countries are sending each other positive vibes?

Because the deal is nonbinding, there are no penalties if the United States pulls out.

Now I’m more confused that ever. If I go to the Big Texan with friends and chow down on a 72 oz. steak (never beat Molly Schuyler, though, sadly), how would they knew whether or not I am still officially adhering to my steamed vegetable diet?

This agreement seems hardly more than an excuse for a lot of highly paid bureaucrats to gather periodically in beautiful resorts at their respective taxpayers’ expense. (Was it ever approved by Congress, the way that a treaty would be? Is the agreement reflected in any U.S. laws?) So the only arguments that I could see for withdrawing are to save money and to save the planet by keeping these folks from flying around to meetings. But here in the U.S. the government spends $4 trillion per year. Cutting expenses at this level is not a Presidential matter.

So why would Donald Trump even bother to mention this nonbinding penalty-free agreement to make, essentially, New Year’s resolutions? And why do my friends think it makes a difference? If they’re interested in keeping up with things that might affect atmospheric CO2, why wouldn’t they be looking more at solar cell production and innovation, windmill design and installations, etc.?

 

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“Chelsea Clinton: Kathy Griffin’s Trump-beheading photo ‘vile and wrong'” quotes Chelsea Clinton as saying “It is never funny to joke about killing the president.”

Let’s accept this as true. But isn’t the necessary implication that it is at least sometimes funny to joke about killing people who are not the president? When are those occasions? And why would it be funnier to imagine the death of a non-president versus imagining the death of a president?

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In October 2008 I wrote “Will Obama be a friend to the poor once in office? Would you?“. Excerpts:

Barack Obama’s campaign has been damaged to some extent by quotes from his days as a community organizer. He sounded like a socialist back then. …

Suppose that Barack Obama arrives in the White House and reminds himself that he still has about 40 years to live, only 8 of which will be spent as President. Those 32 post-presidential years could be spent being celebrated by welfare recipients or as the guest of Fortune 500 CEOs. Those 32 post-presidential years could be spent living on a government pension or as billionaire.

…

My prediction that Obama will win stands, though I fear that my 5 percent margin of victory may be understated now that the Republicans have nominated a candidate who is 90 percent dead. My new prediction is that Obama will be the friendliest president ever to the rich and powerful and that Obama will be the richest person ever to have been president.

Now it seems that Obama is “speaking truth to power” at $400,000 per hour (USA Today).

What do readers think? Did I call this one correctly? Stepping back and taking the long view, was Obama reasonably friendly to the one-percenters (including those in the health care industry!) during his Presidency?

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Eye week started off with a two-hour dissection of the orbit (cavity of the eyeball). We used bone chisels to open the orbit and remove an eyeball by cutting the various ligaments and nerves anchoring it to the skull and brain. A human eyeball feels squishy but not delicate.

The eye comprises several layers: eyelid, cornea/sclera, iris, lens, retina, sclera (again). The eye lids contain conjunctiva epithelia which is continuous with the white outer sclera of the eyeball. The sclera is a white, fibrous connective tissue. The sclera merges with the cornea, a thin transparent convex protrusion that provides much of the optic refractive index of the eye. Behind the cornea is a cavity filled with aqueous humor, a watery secretion. The iris (colored portion of eye) is actually a muscle with radial and circular fibers that control the size of the pupil. The pupil is literally a hole in front of the lens. Light hits the cornea, enters the anterior (front) chamber, traverses through the pupil into the posterior chamber, and hits the lens to be focused on the retina, which is at the back of the vitreous chamber. Classmates, including myself, tended to hear the term “posterior chamber” (in front of the lens) and erroneously identify the much larger vitreous chamber (behind the lens).

Most of my anatomy group left early, but one classmate and I stayed to open the eyeball. We cut open the sclera with a scalpel and held the lens in our hands. It felt like a marble with an opaque yellowish tint. Several cadavers had artificial lenses, which felt surprisingly similar. The vitreous humor, inside the vitreous chamber, felt gelatinous. The retina looked like a white transparent sheet, except for a small protrusion on the medial aspect (closer to the nose) of the retina. This was the optic disk, where nerve fibers merge to exit the eye and the retinal artery enters the eye to supply the retinal layers with blood. The retina peeled off with forceps. We put the eye back together and placed it back in the orbit.

The retina, except at the optic disk, contains photosensitive compounds that transduce light into electrical signals. Rods, cells with the pigment rhodopsin, are sensitive to small amounts of light (as small as a single photon) and line most of the retina. Cones, cells with different photopigments excite depending on the specific wavelength (color), require larger amounts of delivered energy to activate. The density of photosensitive cells increase in an area of the macula with the highest density of cones in the fovea. Rods are important for night vision, while cones enable us to see color and detail.

A student asked, “What is the resolution of the eye?” Doctor J said this is hard to define. Each eye has 150 million photosensitive cells (rods and cones) [compare to 100 megapixels for the highest-resolution cameras circa 2017]. These signals converge onto 1.2 million ganglion cells that transmit the information via the optic nerve to the brain. Most of these ganglion cells originate from the fovea, a region the size of 1.5 mm. Image details are integrated by the primary visual cortex and visual association cortex. If you’re looking for something small at night, try scanning with your peripheral vision because the density of rods is higher outside of the fovea.

Our eyes have six extraocular muscles that provide the extraordinary range of motion of the eye. To support binocular vision and depth perception, the eyes have elaborate mechanisms to maintain foveation through the horizontal and vertical gaze centers in the brainstem. Strabismus (“cross eye”) is a misalignment of each eye causing an image to hit different parts of each retina. Strabismus causes diplopia (seeing double). Compression of one of the nerves that innervates these extraocular muscles can lead to diplopia when they gaze a certain direction.

Our patient case: George, 74-year-old white male with hypertension and hypercholesterolemia presents for blurry vision. An eye exam reveals intact extraocular muscles with decreased visual acuity. Inspection of the macula with an ophthalmoscope reveals the characteristic geometry of drusen (lipid deposits in the choroid vascular region deep to the photopigment layer).He is immediately referred to an ophthalmologist for Age-associated Macular Degeneration (AMD).

[AMD is the leading cause of vision loss for individuals, with white Americans being at high risk starting around age 65. Fifteen percent of white Americans over age 80 have AMD (https://nei.nih.gov/eyedata/amd). Type-A Anita muttered “white privilege” when we went over a clinical trial of a drug to treat AMD. Reflecting the higher prevalence among whites, the study had 93-percent white enrollment.]

The ophthalmologist performed an Optical Coherence Tomography (OCT), shooting low energy light (infrared) into George’s retina to create beautiful micron-resolution images of the retinal layers. The study revealed detachment of the macula due to wet AMD. The choroid plexus (blood vessels on the exterior of the retina that supplies the pigmented cells) began to grow into the photopigment layers causing microhemorrhages. George was fortunate to get this diagnosed before his whole macula became detached.

Every six weeks, George goes to his ophthalmologist for a shot of Bevacizumab (Avastin), which contains antibodies against vascular endothelial growth factor (VEGF). This drug is injected into his vitreous chamber to prevent the growth of the invading blood vessels. “These drugs have saved my vision. I am able to drive, read, really do everything I want to do.” George was going in this week to get his shot before departing on a cruise next week.

“VEGF treatment has really been a godsend,” explained the ophthalmologist. “It prolongs patients’ vision for years. For the unfortunate few who do not respond, there are some other options.” One was a telescope implant to replace the lens with a magnifying telescope that focuses an image on a different part of the macula that is healthy. Students dubbed this “going bionic”. A more drastic treatment option is macular rotation. Surgeons detach the retina and rotate is to have a new, more healthy vascular choroid plexus.

A student asked about the difference between Avastin, originally developed as a treatment for colon cancer, and Lucentis. Lucentis, FDA-approved to treat wet AMD, is a cleaved form of the anti-VEGF monoclonal antibody Avastin, at roughly 1/40th of the dosage used for colon cancer patients. Lucentis may be able to penetrate deeper into the retinal layers because of the antibody’s lower molecular weight. Lucentis costs $2,000 per dose, whereas the amount of Avastin necessary for wet AMD therapy costs $50. The ophthalmologist explained he always starts with off-label Avastin. “I have only anecdotal evidence that a few of my patients respond better to Lucentis.” [This makes sense given that the drugs are essentially chemically identical.] Genentech makes both Avastin and Lucentis. “Why would the company fund a multi-million dollar trial to approve a drug that costs less?” If all Medicare patients were prescribed Avastin instead of Lucentis, Medicare Part B is estimated to save $18 billion and patients save nearly $5 billion over a 10-year period (http://content.healthaffairs.org/content/33/6/931.abstract).

That evening, I spoke with some fourth-year medical students going into surgery about the match process. I learned that many general surgery (“Gen Surg”) residencies are trending towards the “5 + 2” option. Gen Surg residencies had typically been five years. After residency, you could then get a job, or apply to a 1-2 year fellowship (e.g., cardiothoracic, vascular, etc.). In order to make graduates more competitive when applying for fellowships, some prestigious surgery residencies are now requiring two years of research in the middle, hoping that the publication record will appeal to fellowship admissions committees. Thus what had been 4 years of medical school, plus 5 years of residency, plus up to 2 years of fellowship (11 years) might now turn into a 13-year training process.

An attending repeated his wish (see Week 8) that regulations would allow him to teach us more. “LCME caps the number of formal class hours at about 26-28. There just isn’t enough time to do extra projects, especially if they do not advance LCME-designated areas.” He told administration that he would even volunteer his time for optional events. “Administration responded by saying, ‘Students would complain that they feel obligated to go…’ Don’t we have capitalism? Instead of stooping to the lowest denominator, you work harder, get better, and make more money.”

At lunch, Type-A Anita lamented the loss of Obama. Several students agreed, but added, “Trump’s election is actually a blessing. Now we have unprecedented activism against racism and sexism. In the long run this will be good.” Type-A Anita agreed, “But honestly, if we blow up the world?” They ended by saying how much they missed Obama’s dogs and looking at a Pinterest account of Merkel Faces.

Statistics for the week… Study: 10 hours. Sleep: 7 hours/night; Fun: 1 night. Example fun: Afternoon drinks at recently opened brewery. There must be six new breweries planning to open by the end of the year.

More: http://fifthchance.com/MedicalSchool2020

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The AOPA review of the Cirrus Jet contains some interesting parts. For example:

as we’ve come to expect from Cirrus, this model has a whole-airplane parachute. … And, because of the jet’s greater speed operating envelope, a pull of the overhead T handle in the jet doesn’t necessarily immediately fire the rocket to deploy the chute. Instead, if the airspeed is above about 135 KIAS, the autopilot takes control, doing what is necessary to slow the airplane.

Finally an aircraft manufacture writes some software that vaguely makes sense! (Don’t think that you need a parachute given the historical reliability of turbine engines? Consider that our government’s elaborate regulatory apparatus didn’t bother to insist that the drones imported into the U.S. have an automatic collision-avoidance capability with respect to human-occupied aircraft! If you hit a drone you’ll be a lot happier in a Cirrus than in Hillary Clinton’s Gulfstream G450!)

The airplane has limited payload and range, but it promises to be simple to operate. My friends are heaping derision on this product, comparing it to a TBM (longer range, higher speed turboprop). I think the right way to look at this airplane is as an improved SR22 for about twice the price ($2 million instead of close to $1 million for a fully optioned SR22). What if you want to take a few friends to Bar Harbor, Maine from Boston or New York? Or fly from Boston to D.C.? Or SF to LA? JetBlue and United beat (literally beat in the case of United, of course!) any GA aircraft for a flight longer than that.

Disturbing omission from the review: interior noise. The fuselage is composite, usually a recipe for an oppressively loud cabin. The engine is bolted to the top of the fuselage instead of placed out on a pod or a wing.

Readers: Now that you’ve seen this review, what do you think of the Cirrus Jet? At what price would it be cheap enough to revitalize consumer interest in general aviation? [personal estimate: $500,000; Flying from December 1970 says that an A36 Bonanza, a mass-market 6-seater, had a base price of about $50,000 back then ($307,000 in today’s mini-dollars).]

Related:

• official company product page
• Plane and Pilot preview

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Here are a couple of walk signs in Trafalgar Square:

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A Londoner told me that part of the country’s divide regarding Brexit was based on the fact that EU membership had made it easy for employers in London to grab up the best people from any European country experiencing an economic or political crisis. “When Spain collapsed, all of the best people in Spain were available to the banks here,” he said. “That’s been great for London, but it doesn’t help people to the north.”

The cream of the European crop is already in London (and how many more crises can Europe have?), and London has certainly run out of housing, sidewalk space, etc. So even without Brexit perhaps the city’s economic growth was due to slow?

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In anatomy, we performed a laminectomy. We removed the posterior vertebral structures to reveal the spinal cord, about the diameter of the thumb. We opened up the dura (outer meninges that forms a fibrous protective layer), a continuous white sheath that covers both spinal cord and brain. At each intervertebral level, four roots come off the spinal cord to form bilateral spinal nerves. The ventral root is where all the motor fibers exit the spinal cord to control muscles and glands. The dorsal root is where sensory fibers enter into the spinal cord. Several spinal nerves in the lumbar and cervical regions were surprisingly large, about the diameter of a pinky. How could something the size of a thumb contain nerves that occupied so many pinkies? The answer turns out to be that nerves within the spinal cord are highly myelinated, which maintains conduction speed without the need for a large diameter. Once the neurons fan out from the spinal cord, however, not all of these nerves are myelinated and therefore must be thicker. We also saw the aptly named cauda equina (horse’s tail). The spinal cord stops at L4 but the spinal nerves must exit from the lower vertebrae. The spinal nerves flow down the vertebral foramen fibers forming a horse’s tail!

This week in lecture we learned about the cerebellum (from the Latin for “little brain”) and basal ganglia. The cerebellum is located in the posterior inferior (back/lower) portion of the skull under the occipital lobe and contains an estimated 50 billion neurons in the cerebellum—more than in the entire rest of the brain and spinal cord combined! These cells can be thought of as writing computer programs to determine muscle activity and timing. One program, for example, might determine the sequence of firing hand muscles to grasp a cup. “Anyone who has had one too many cold ones knows what happens when you lose cerebellum function,” noted Doctor J. Alcohol affects the the purkinje neurons of the cerebellum first, causing the characteristic drunk stumble.

The cerebellum uses the same neural architecture to process different inputs. For example, whether information is coming from the vestibular (balance) apparatus, or coming from proprioceptive information of the big toe, the information ascends to the densely packed purkinje neurons. The purkinje cells form massive planar dendritic trees that stack together in parallel. Purkinje cells have the same branching pattern as fan coral. Information received from the nervous system is sent along parallel fibers that travel perpendicular to the purkinje dendritic trees, synapsing along the way. This allows an immense amount of connectivity.

Cerebellar lesions, for example from a stroke, are devastating. Simple tasks become near impossible as the victim has difficulty timing an action. We practiced various cerebellar tests including the finger-to-nose test where you ask patients to reach out to your finger and touch their noses. They will have an intention tremor as they near the end of the action. Doctor J commented, “Do not use their nose as the endpoint. A stroke patient will poke his/her eyes out. Use the chin.”

We had two lectures on the basal ganglia, cell bodies deep in the brain that are involved in filtering information passing through the thalamus (relay station) to the cerebral cortex. While the cerebellum’s outputs dictate the timing of muscle firings, the basal ganglia determine which muscles need to be activated. Lesions of the basal ganglia, for example Parkinson’s disease, cause debilitating rest tremors (tremors while not performing an action). We learned that stripes of tape on the floor can help Parkinson’s patients with stability. The visual cues of the tape are thought to override the abnormal baseline thalamic input. This simple addition has huge benefits for the patient and caretakers, for example, when the patient tries to get out of bed to the bathroom. “This is an easy way to help keep a Parkinson’s patient out of the hospital.”

Doctor J brought out a VHS cassette showing various tremors, reflexes, and symptoms of patients with neurological disorders. “It might be old, but it’s the best display of these symptoms.” It took two IT staff 15 minutes to get it playing. We saw symptoms and movements associated with Parkinson’s disease and Huntington’s disease. The video was apparently worthwhile; the next day, a classmate shadowing an internist diagnosed a 40-year-old patient with Parkinson’s.

Our patient case: Martha, a 62-year-old female with Parkinson’s disease accompanied by her daughter Janine. The class quickly fell in love with Martha. She was witty, humble, and kind. Martha was diagnosed about eleven years ago with Parkinson’s after presenting with balance issues, difficulty writing, and a rest tremor in her hands. The neurologist explained there are two stages of Parkinson’s. “The first stage involves movement and dexterity. Typically two decades after diagnosis, patients enter a second phase characterized by significant cognitive deterioration. There are drugs, for example carbamoyl-levodopa, that are effective at treating the tremor and movement disorders.”

Martha explained that it took a while to find the right balance. Too much of these powerful drugs can also cause tremors. She takes her medications every four hours or as needed if the tremors get worse. “If I do not take my medications, I have this terrible slowness,” explained Martha. “I want to walk but my feet do not move. They just twitch up and down with the rest of my fidgety body. My body does not respond to my mind.”

Asked to describe her typical day and what she wanted others to know about Parkinson’s, Martha responded, “Oh, I still do lots of stuff. I cannot drive, but I love to garden and cook. Everything just takes longer for me. Appreciate that it is difficult for me to get to an appointment or brunch at 10:00 am. It takes me several hours with the help of Janine to get ready.”

What was her greatest concern? She immediately responded, “That I will become dependent on Janine.” She explained that Janine was the only family member who was a significant help. A student asked Janine, “How has this changed your life?” Janine responded, “She is the center of my world. I wouldn’t change it. I wish people understood that her disease has not destroyed everything of her. There is a whole life after diagnosis. It doesn’t stop there.”

Friday afternoon, we practiced motor and reflex tests on each other. Reflexes are elicited by sudden changes in muscle length. Swinging a reflex hammer at a tendon causes a sudden increase in the length of the tendon, which sends this stretch information to reflex centers in the spinal cord. Upper motor neurons communicate with these centers for a net inhibitory effect. Therefore, an upper motor neuron lesion may result in hyper-reflexia (e.g., doctor gets hit in the nose by the patient’s foot). As we practiced on each other, two student-examinees shouted, “I got the clonus!” Clonus is when a muscle undergoes a series of involuntary contraction-relaxation cycles after a sudden change in the fiber length. The hospitalist told them not to get too excited about a few beats of clonus: “Wait until you are on the hospital wards.”

Seven students stuck around to speak to the physician. One of our classmates had suffered a stroke at age 10. He reluctantly volunteered to have his reflexes tested. We quickly identified hyper-reflexia in his left lower extremity (left leg below the knee). For the patellar reflex (knee), the leg straightened at the knee and then kept going up towards the ceiling. After that we saw more than 5 seconds of sustained clonus. This is entered on a chart as “Grade 4+” (2+ is normal). Further, the physician elicited the “Babinski sign” by moving a pen along the underside (“plantar” surface) of the classmate’s foot. His toes fanned out, which is normal for a baby under six months old. After six months, this reflex is typically eliminated as upper motor neurons suppress the primitive response. We thanked our good friend and classmate.

The next day, Doctor J held a group “question and answer” session. The class gets into six-person groups to answer challenging questions. Each group is required to hold up an answer. Doctor J would then delve into why Group 1 picked “C” whereas Group 2 erroneously picked “D”. Type-A Anita did not attend stating, “I feel humiliated when I go to these question/answer sessions and he pimps me about why I got the question wrong.”

Lunch outside with nine classmates: A woman checked CNN headlines about the missile strike on Syria on her phone and yelled that Trump was a warmonger. Type-A Anita added, “On top of this, Gorsuch was confirmed. We are going back to the Stone Ages.” The topic somehow turned to race relations. A classmate chimed in, “Ben Carson got appointed only because he is black.” A female classmate from a rural conservative family opined, “America has our class divisions but we are by far the most tolerant country compared to anywhere else.” Immediate reactions stormed in. “This is because Western culture portrays whites as heros and blacks as criminals,” a female Asian student asserted. “It is the West’s fault that other countries are not tolerant because they watch our movies and pop culture.” The discussion settled down after someone brought up the livestream of April the Giraffe (a pregnant resident of an animal park in New York).

Statistics for the week… Study: 8 hours. Sleep: 8 hours/night; Fun: 1 night. Example fun: After class, we played soccer with Ph.D. students in the rain followed by burgers and beers.

More: http://fifthchance.com/MedicalSchool2020

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Two London-based Airbus A320 captains explained the avionics in their $100 million workhorse: “Because of certification regulations, none of it has been updated since the 1980s. When you touch a button you can see the computer working to update numbers. It would be a lot better to have one iPad per side running SkyDemon.” (This would replace the navigation equipment of the Airbus; the primary flight display for attitude, airspeed, etc. would remain.)

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Anatomy lab was less than 30 minutes: we removed with blunt dissection the posterior muscles around the vertebral column to prepare for next week’s laminectomy (removal of the vertebral laminae to expose the spinal cord)! We went over spine anatomy and common spine disorders such as a herniated (“slipped”) disk (the gelatinous nucleus pulposus part of the intervertebral disk herniates through the outer fibrocartilage annulus fibrosus) and spondylolisthesis (anterior or posterior displacement of a vertebra). We discussed how aging causes loss of the elastic dampening capabilities of the nucleus pulposus.

Lectures detailed two sensory systems, the anterolateral and medial lemniscal tracts. The anterolateral tract conveys tissue damage (pain), whereas the medial lemniscal tract conveys fine touch and proprioception (vibration and positional awareness). Sensing vibration requires extremely responsive transducer elements in the skin to convert rapid changes in pressure into electrical signals. All these tracts end in the postcentral gyrus in the cerebrum, which forms the sensory homunculus. The medial part receives sensory input from the lower extremity. The genitalia neurons are adjacent to the foot neurons, a potential explanation for why some humans have a foot fetish. The lateral part of the brain receives sensory input from the upper extremities.

Doctor J called the tallest student up to the front. He grabbed a measuring tape and asked the student to step on one end of it. He then measured all the way up his back to the end of his neck — 5’6. “This is the length of a single neuron in your body.” The whole class was amazed. Neurons that sense fine touch and proprioception travel from the big toe up to the spinal cord, ascend the spinal cord in large bundles, and finally synapse in the medulla (part of the brainstem). One cell.

Our patient case: Sherry, a 50-year-old overweight female accountant with uncontrolled diabetes presents to her primary care physician with a foot ulcer. During tax season she is so busy that she forgets to take care of herself. She has not refilled her medications, including metformin, for several months. A neuromuscular exam, specifically using a 256 Hz tuning fork to test for vibration sensitivity, reveals diminished sensory ability in both extremities. She explains that her foot has felt numb for weeks. A cut on the foot went unnoticed, and got infected.

Sherry suffers from diabetic peripheral neuropathy. Uncontrolled glucose levels lead to non-enzymatic glycosylation (adding sugar groups) of proteins,lipids, and nucleic acids. These advanced-glycosylated products (AGEs) interfere with normal function and activate inflammatory pathways. A familiar complication of diabetes is vascular (arteries and veins) damage, which leads to increased risk of atherosclerosis, heart attack, and stroke. This inflammation also damages neurons and their companion Schwann cells (cells that myelinate peripheral nervous system axons). The longest axons are affected first. The neurological deficits such as numbness, loss of pain sensation and balance difficulty start in the foot and travel up the leg. By mid-calf, the sensation loss also begins in the hands. Fifty percent of diabetics have peripheral neuropathy (eighty percent after 15 years). Interestingly, the physician mentioned that twenty percent of prediabetics have some sign of developing nerve damage, suggesting that vibration tests should be used as a screening tool for diabetes.

Sherry had trouble simply walking. As is common among laypeople, classmates associate diabetes with laziness: failure to exercise, overeating. This case prompted us to ask “How could someone exercise if they cannot walk?” The physician concluded, “It is critical for diabetics to check their feet daily. They might not even realize they have a cut or foot ulcer. The infection can spread to the bone requiring hospitalization and, too commonly, amputation.” He reminded us that diabetes is the leading cause of amputations [73,000 in 2010]. Sherry described her diabetic foot ulcer, now cured, as a wake-up call. She was discharged from the hospital three months ago and has been taking her medications regularly.

A diagnostic radiologist and an interventional radiologist led a lunch session about their respective specialities. Diagnostic radiologists complete 5 years of training: an internship year typically on general surgery followed by a 4-year radiology residency. Interventional radiologists conventionally would complete a separate 2-year interventional radiology (IR) fellowship, making for a total of 7 years of post-MD training. There are now direct IR residencies that take just 5-6 years.

IR is a subspecialty of radiology. Interventional Radiologists perform minimally-invasive procedures using imaging guidance such as x-ray and ultrasound. These procedures include: central line placement, endovascular (e.g., stents and thrombectomy of blood clots) procedures, radiation treatment, and bile duct obstruction procedures. Other specialities overlap with many of these. Indeed, there is sometimes tension what specialty group performs a given procedure at different health systems. For example, stents can be placed by IR or interventional cardiology; strokes can be treated by neurosurgery or IR.

The interventional radiologist explained why he chose IR: “I loved anatomy. And I like working with my hands doing procedures.” The diagnostic radiologist explained why she choose radiology: “I had the worst internal medicine rotation fourth-year. Day after day, I would have a patient die on me. The worst was a 30-year-old cystic fibrosis patient, the exact same age I was. I was so miserable I considered quitting medical school or not completing a residency. A radiologist lived upstairs of me and noticed how miserable I was. He suggested I shadow radiology. Never looked back.”

She described radiology as the “experts’ expert.” Clinicians increasingly rely on imaging procedures as opposed to physical examination skills. “Do not go into radiology if you cannot wield responsibility. You decide if someone in the ED goes to the OR or gets sent home.” We learned that radiologists are highly compensated, but also have a higher liability profile: “Every radiologist will be sued several times.”

What will the role of machine learning play in radiology? “Computers will not replace radiologists. They will just make radiologists much better at their jobs.” The diagnostic radiologist elaborated, “Computer algorithms in some areas are just as good as radiologists in identifying if something is wrong with a patient [high sensitivity]. However, computers are terrible at ruling out issues [low specificity].” I attended a neurosurgery informal dinner where I asked a similar question about radiology. The neurosurgeon was shocked by the radiologist’s response, and exclaimed, “Radiologists are terrible at ruling things out. Every report is littered with: ‘cannot rule out x, y, or z’. Give me a break, they will be replaced.” (See “A.I. Versus M.D.,” New Yorker, April 3, 2017.)

I’ve been working on a personal project in the evenings. My favorite trauma surgeon comes in most Wednesdays at noon to evaluate my progress. She tidies up my dissection then sends me on another mission that our class did not have time to explore during formal anatomy lab. Examples: Find the annular ligament of the radius, the ulnar nerve, or the anterior humeral circumflex arteries. One thing that makes medical school different is that an after-hours project may involve a dead body. In this case, I have a whole cadaver to myself, unlike in anatomy lab where we switch bodies every few months. The cadaver was a black 60-year-old, mildly overweight female. I have developed a deep sense of appreciation for this woman who donated her body so that I could pursue this upper extremity (arms) project focused on nerve and blood vessel anatomy.

One evening around 9:30 pm there was a knock on the locked door. I took off my soaked gloves and opened the door to find the head dean escorting a fundraiser group of dressed-up bankers and business people. They wanted to see the wet lab. I forgot how quickly one adjusts to the sight of cadavers in a formaldehyde-scented room. As I was there by myself, the whole head was uncovered and several chunks of removed fat lay exposed. A few people approached the body, but most were hesitant and stayed at least several feet away. I showed them the nerves and vessels of the arm.

A visitor asked about the purpose of cadavers. I explained that cadavers give unparalleled understanding of human anatomy. Textbooks cannot replicate this experience, especially the geometric relations of anatomical structures. An important part of the learning experience is discovering how the individual died and what diseases he or she lived with. I mentioned that one cadaver had a heart attack, prompting a question from a gentleman in his late 50s regarding what the heart looks like after a heart attack. I explained the cadaver suffered a heart attack in his left anterior descending (LAD) artery, as evidenced by a small, hardened discoloration on the surface of his left ventricle (see previous post). He did not die from the myocardial infarction because hardened scar tissue replaced the infarcted region. If he did die from the MI, the infarcted region would have the same firmness as the rest of the myocardium. The gentleman thanked me, took a peek at the cadaver and left. The next day the dean told me that the wet lab had been the guests’ favorite part of the event.

Statistics for the week… Study: 8 hours. Sleep: 6 hours/night; Fun: 1 nights. Example fun: Two classmates and I attended this year’s SonoSlam in Orlando, Florida. SonoSlam is an ultrasound competition among medical schools held on a Saturday by the American Institute of Ultrasound in Medicine (AIUM). My favorite part was using the most advanced ultrasound machines. Several of machines were controlled via iPads. One bluetooth-enabled ultrasound probe was only slightly larger than a smartphone and could be controlled via an iPhone app. The competition ended around 6:00 pm. As first-year students without the pathology training of the fourth years, we had low expectations for the competition and we did not exceed them. However, we celebrated our failure with post-competition drinks at a local brewery and “Cutthroat” at a nearby billiards parlor.

More: http://fifthchance.com/MedicalSchool2020

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