The Power of Analogy

February 16, 2013  |  Neurology Study  |  No Comments

When I was a budding doctor last year, I found it very difficult to express my knowledge properly to my patients, because I often answered their questions with the stiff sentences from textbooks (and I guess some of the patients found it hard to understand my words too, especially for those came from the countryside!). I really had a hard time at that moment, and what was worse—I didn’t even know how to make a change. Until, one day, when we were carrying on with ward rounds, I heard our doctor-in-charge explaining the pathogenesis to one patient. “You can imagine the vascular to be a water pipe”, she said, “and the plaque is just like scale. If there’s too much scale, it will block the pipe, so that water cannot go through it. And this situation is the same with vascular.” Then the patient smiled, nodded and said he understood. I was very surprised to see what power the analogy had, and how it could make communication easier in clinical practice!

Since then, I often drew analogies to explain to patients about their illness, and I find proper metaphors worked very well:) I also learn many interesting analogies from here (link). Fight on analogies!

Practice makes perfect

January 19, 2013  |  Neurology Study  |  1 Comment

Back when I was an undergraduate student, before my internship, one of our professors told us: “To patients, you are doctors, not just students. You may start things like an amateur, but it doesn’t matter, because practice will make you an experienced doctor. So, you don’t have to worry too much when beginning your clinical practice.” Then he told us the old Chinese story of the oil peddler (English translation is from here)


During the Northern Song Dynasty, there was a skilled archer. One day he drew a big crowd while he was practicing on the drill ground. He shot so accurately that the on-lookers cheered with excitement. He became very proud of his skill. But among the crowd an old oil peddler only nodded his head indifferently. This hurt his Pride. He asked the old oil peddler:

-“Can you do this?”

-“No, I can’t.” 

-“What do you think of my skill?” 

-“Just OK, but nothing special. You’ve gained your accuracy from persistent practice. That’s all.” 

-“What can you do, then?” 

The old man said nothing. He put a gourd bottle on the ground and covered its mouth with a copper coin. He then scooped out a ladle of oil from his big jar, held it high and began to fill the bottle. Now, a thread of oil came down from the ladle into the bottle just through the hole of the coin. Everybody looking on watched with amazement. But the old man said, “This is nothing special, I can do this because I have practiced it a lot.” And with these words, he left. 

Later, people use this phrase to mean “Practice makes perfect”.


I have this story in my mind all the time. I still remember when I just started working as an intern doctor, I was worried about my lack of experience. But I encouraged myself: that’s okay, it’s not a big deal – I cannot remember everything from the beginning. I will do it better in the future by repeating my practice.

“Practice makes perfect” – it’s like a magic spell for me and makes me much more confident. Now I’m a doctor full of confidence. I believe that if I keep on working hard and practicing, I will become a great doctor.


Trochlear nerve palsy

November 20, 2012  |  Neurology Study  |  1 Comment

Recently, I found there was an interesting case about a male patient with trochlear nerve palsy.

The patient is a 60-year old man. Let’s call him David. 10 days ago, David got a dizziness and double vision, and the symptoms came with fatigue and bilateral hearing loss. After that he went to the hospital, there he had a head CT scan which showed “cerebral hemorrhage” (and its cause was confirmed as arteriovenous malformation).

The neurologic examination revealed that David had diplopia when his eyes moved downward and to the left. In addition, his bilateral pupils were 3 mm in size and had good light reflex. Other examinations were normal.

Figure1. David's MRI (axonal T1)

Figure 2. David's MRI (sagittal T2)

It is rare to see single trochlear nerve injury case, and David’s case happens to be an excellent opportunity to review trochlear nerve function.

A Review of trochlear nerve

In 1561, an Italian the anatomist Gabriele Falloppio first described the structure of trochlear nerve in his book Observationes Anatomicae. One hundred years later, another anatomist William Molins named the nerve “trochlear nerve”.

Figure 3. The trochlear nerve 1 (Adapted from DUUS’ Topical Diagnosis in Neurology)

Figure 4. The trochlear nerve 2 (Adapted from Symptoms and Diagnosis of the Nervous System Diseases 《神经系统疾病症候诊断学》)

The nucleus of the fourth cranial nerve lies ventral to the periaqueductal gray matter immediately below the oculomotor nuclear complex at the level of the inferior colliculi. Its radicular fibers run around the central gray matter and cross to the opposite side within the superior medullary velum. The trochlear nerve then exits the dorsal surface of the brainstem (it is the only cranial nerve that does this), emerging from the midbrain tectum into the quadrigeminal cistern. Its further course takes it laterally around the cerebral peduncle toward the ventral surface of the brainstem, so that it reaches the orbit through the superior orbital fissure together with the oculomotor nerve. It then passes to the superior oblique muscle, which it innervates. (Adapted from DUUS’ Topical Diagnosis in Neurology)

Figure 5. Diagram of eye position in the six diagnostic positions of gaze, in which weakness of one or more of the extraocular muscles can be most easily detected. (Adapted from DUUS’ Topical Diagnosis in Neurology)

Figure 6. Eye position and diplopia in trochlear nerve palsy. (Adapted from DUUS’ Topical Diagnosis in Neurology)

Patients with trochlear nerve injury can have a head tilt to unaffected side.Unfortunately, because David was not my patient, I did not see him by myself in the very end.

Oculomotor nerve palsy (1)

August 7, 2012  |  Neurology Study  |  No Comments

We had two female patients with oculomotor nerve palsy hospitalized in two consecutive days. I made a comparison between their conditions and found it very interesting.

Patient #1 (Let’s call her Mary): Mary is 60 years old, and she was admitted to hospital because of recurrent headache for two months and right ptosis for 10 days.

Two months ago, Mary got a headache in a sudden after using her full strength to lift a heavy object. Her headache came with throbbing pain on the top right side of head. She said she can hardly bear it. She also had a blurred vision and felt dizzy and sick although she didn’t want vomit. The doctor in a local clinic gave her some infusion therapy (unknown) and her headache was relieved in two hours. However, after some time she had the same symptoms, which repeated every 1 to 2 hours. She said it became more severe when she got up, exposed to intensive sunshine or coughed. Taking painkillers cannot make her relieved with the headache. About one month ago, Mary had a head CT scan and the result was normal. About 10 days ago, she suddenly had right ptosis and diplopia in the horizontal direction.

Our neurologic examination revealed that Mary’s right eyelid was drooping and completely covered the right eyeball, and right eye movement was limited when it moves towards left, upper and lower directions. Also, she had diplopia when her eyes moved to the left. In addition, her right pupil was 5 mm in size and had poor light reflex. The size and light reflex of her left eye were normal. (One day before the examination, Mary hit her head onto the edge of a table, so she had ecchymosis on her periorbital skin.)

Mary’s pupils are like the picture below:

Mary's pupils


The eye movements of Mary are presented as below:

Mary's eye movements


Patient #2 (Let’s call her Linda): Linda is 61 years old. She was admitted to hospital because of vertigo and headache for eight days and left ptosis for 6 days.

Eight days before her presentation, Linda suddenly got vertigo and blurred vision after doing some manual labor work. Her vertigo came with a headache (presented as throbbing pain) and nausea. She didn’t feel like vomiting and felt better when she lay down and rested for a while. The next day she got a gradual onset of weakness of her left eyelid, and 2 days later she found it was difficult to open her left eye.

Our neurologic examination revealed her left eyelid was drooping and completely covered the left eyeball, and her left eye movement was limited when it moved towards the right and upper directions. In addition, her bilateral pupils were 3 mm in size and had good light reflex.

Linda’s pupils are like the picture below:

Linda's pupils


The eye movements of Linda were presented as below (she was not very cooperative when we took photos of her eyes, so you may see her normal eye (right eye) is not in place in some directions):

Linda's eye movements


I will review details about the causes of their diseases with you in the future.

The Details We Neglect

The Details We Neglect

October 18, 2011  |  Neurology Study  |  2 Comments

When I was browsing a Chinese medical forum recently, a discussion about dietetic treatment suddenly drew my attention. It made me think of one of my internship experiences at the Department of Neurosurgery. It was about a mid-aged male patient with diabetes mellitus (DM), and whose daily diet and medicine were taken irregularly. We knew this during the routine patient rounds, and then the professor asked me to introduce some basics of DM to this patient. Later, I searched on-line and printed two articles with easy-to-understand content for him. When I gave them to the patient, I also talked about DM, such as what the normal range of blood sugar was. I was confident that I “taught” a clear idea about DM for him and his family. However, when his wife asked me whether he could eat apple and how much he could ate, I was stunned, for I never thought about such details about DM diet treatment. What I knew was just the concepts, the theories, such as what DM was, what medicine was used for treatment and what their side effects were as well as the concept of so-called “diet control”.

In fact, treatment of a disease like DM can be very specific, much more than those printed in textbook. “Diet control” is just one from a thousand aspects, and it could be so complicated that they are different from person to person. Sometimes, it is right what the patients really want but what we neglect. Let’s not ignore them anymore.

My Start in Neurology Study

My Start in Neurology Study

October 14, 2011  |  Neurology Study  |  2 Comments

“Complexity” is my first impression for the study of anatomy of nervous system. At that time, I was just a freshman in a medical university and trying to digest all the medical knowledge I learned from class. Although I worked hard to organize the overwhelming information in the nervous system, lacking effective learning method made it difficult to understand or remember all the stuff.

Then in my fourth year of college, the course “Neurology” changed it. The first class of this course was taught by Mr. Pan, the director of Neurology Department from the affiliated hospital of my university. He was a kind man with a strong sense of humor, and he talked about lots of attractive cases during the class. It was the first time that my interest in neurology was inspired. Next, during another class about “Diseases of the Spinal Cord”, the teacher (another doctor) walked into the classroom, put down his bag, took a piece of chalk then drew a very simple but clear picture of spinal cord, including segments and a cross section. Suddenly I realized my hobby – drawing pictures – might be just the right way to study this course — I could actually draw “the knowledge” out! I believe this was a start for me to face my study in Neurology positively.

Since then, drawing turned into one of my unique method of learning the subject. I always found the anatomic structures become much more clear after I drew them in my notebook, even if it just were complicated pictures the same as in the books. My feeling for learning by drawing was so fantastic that I was totally immersed in it.

I am lucky, because besides my unique learning by drawing, I also found awesome books that are precious in my study, such as Duus’Neurologisch-topische Diagnostic Anatomie-funktion-Klinik (By Peter Duus). I happened to find it in the library during preparation for my exam. I could not help copying so many beautiful pictures down into my notebook.

Here are two I’ve drawn during this time:


After that, I determined I would choose Neurology as my major if I continued study after the 5-year college. During the interview of entrance examination for postgraduates, I introduced my pictures to the professors. I believe my learning method was so unique that it attracted them a lot. Finally, I passed it very easily, and now I am a Master student at West China Center of Medical Sciences :)

This is my experience.

So, how did you fall in love with your specialty?