An “Egg-cellent” Journey to Investigate Carotid Artery Stenosis in Cambridge, Ontario…

Last Wednesday, my ROP students Kiersten and Indranil, and UofT medical student Eli Lechtman had the opportunity to interview the legendary (see here) Dr. Kim Tysdale – a general practitioner in Cambridge, Ontario.

Why do you ask? Well each year 50,000 Canadians suffer from a stroke with 26% due to carotid artery disease. Carotid artery stenosis is the narrowing of the carotid arteries due to plaque buildup (see atherosclerosis). These plaques can then rupture and create blood clots that travel up to the brain. In turn, these blood clots then get stuck in the brain’s smaller blood vessels, causing a stroke. So plaque = bad and ruptured plaque = worse!

What if we had a clue as to which plaque may rupture? Well, in turns out that the presence of intraplaque hemorrhage (IPH) can help us predict just that! IPH is bleeding within the plaques, which causes them to become more vulnerable (see vulnerable plaque). There is a 6 times greater risk of stroke in people with IPH! And…. a new medical imaging technique called MRIPH imaging allows for visualization of IPH. MRIPH is similar to traditional MRI but highlights the artery walls and looks at the arterial plaques. 

While in Cambridge, Kiersten, Indranil, and Eli presented Dr. Tysdale with an overview of medical imaging techniques for the assessment of carotid artery stenosis with an emphasis on the new MRIPH technique. Informing physicians like Dr. Tysdale which of his patients are more at risk of having vulnerable plaques (by providing information on IPH) could result in patients receiving more appropriate and timely treatment – thereby reducing the number of strokes! 

BTW, we had Dr Tysdale at “hello” (not sure what I am referring to? See here).

So what up with the eggs? Kiersten, Indranil, and Eli also had the chance to tour Dr. Tysdale’s beautiful country house and meet his lovely wife (and nurse!), Eva, who sent everyone home with fresh chicken eggs! Awesome.

Thank you Dr Tysdale for being such a great sport!

Here is their infographic of the trip (great job gang!). Enjoy!

Kiersten Thomas and Indranil Balki – ROP Summer 2015

Stay tuned for more ROP adventures!

Pascal Tyrrell

MiWord of the Day Is… Haptoglobin!


Just got back from the RSNA! Wow what a big conference – 56,000 people this year. McCormick place in Chicago, Illinois (where the conference is held) feels like an airport it is so big. 

Love Chicago. Great city. 

Of course, I had the pleasure of attending a bunch of great presentations and today I will introduce you to one of them. Tina Binesh Marvasti (say that 7 times fast!) presented on the topic of Haptoglobin. No, not Hobgoblin (not sure who that is? See here) or his infamous green predecessor (see here). 

So, what is Haptoglobin you ask? It is a serum protein that binds free hemoglobin – resulting from the breakdown of red blood cells – and functions to prevent loss of iron (contained in the heme group) through the kidneys and to protect tissues from the highly reactive heme groups. Essentially a housekeeping protein that helps to recycle hemoglobin as part of the red blood cell life cycle. Now what if your ability to clean-up free hemoglobin was impaired? Well, quite simply you would be putting at risk those sensitive tissues that come into contact with free hemoglobin. 

One important example of this is vessel walls affected by atheroma (AKA plaque). Sometimes these atheroma can bleed (called intraplaque hemorrhage or IPH) which worsens the whole situation. Typically, your body responds by sending the clean-up crew including the Hobgoblin (or haptoglobin, I always get these two confused). 

When people have the recessive genotype (Hp 2-2) of the Hp gene they produce less haptoglobin and therefore are at increased risk of damage from free hemoglobin (or more specifically the heme groups).

Tina and friends hypothesized the following: 

And she found that having the recessive Hp2-2 genotype was associated with a higher prevalence of IPH in a group of  80 patients (average age of 73 yrs). She also found that the IPH volume of Hp2-2 patients worsened over time.

So what is the take home? The Haptoglobin genotype is associated with IPH which is a biomarker of high risk vascular disease and could identify populations at higher risk of developing cardiovascular events.


Now for the fun part (see the rules here), using Haptoglobin in a sentence by the end of the day:

Serious: Hey Bob, did you know that a recessive haptoglobin genetype may contribute to an increased risk of cerebrovascular disease?

Less serious: My GP suggested that based on my recessive hobgoblin genotype I should consider a healthier lifestyle. Funny, I always figured Doc Ock to be the one to watch for…

OK, watch the Spider-man 2 trailer to decompress and I’ll see you in the blogosphere…

Pascal Tyrrell