Tag: University of Toronto

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Research Opportunity Program: Cost Effectiveness and Imaging Carotid Stenosis

ROP Research Forum March 5th, 2015 – Sylvia Urbanik

Sylvia is a second year student studying cell and molecular biology. She is currently finishing up her Research Opportunity Program that spanned the fall and winter semesters, and also recently represented us at the March 5th ROP research forum along with her partner and predecessors.

 
Her project dealt with cost-effectiveness analysis techniques for diagnostic imaging modalities, with a specific focus on carotid artery stenosis. She explored the different types of analyses used in assessing cost effectiveness. She examined how factors such as sensitivity and specificity of diagnostic tests (imaging modalities in this case) can affect the analysis, and conducted literature searches in order to find these variables in order to incorporate them into a cost effectiveness model.​

Well done, Sylvia!

Stay tuned, next Kevin Chen will be modeling with TreeAge…

See you in the blogosphere,

Pascal Tyrrell

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Research Opportunity Program: Imaging Carotid Stenosis

ROP Research Forum March 5th, 2015 – Helena Lan

Helena is a second-year student pursuing a specialist in Pharmacology and Toxicology at the University of Toronto. Participating in ROP299 this past summer (see here) has opened many doors for her. She is currently assisting Pascal on a systematic review on research methodology and biostatistics in medical imaging, working as a research assistant for a medical education study, participating in the research abroad program at Karolinska Institutet this summer… and recently represented us at the March 5th, 2015 ROP research forum!

Helena examined the technical aspects and information provided by two major imaging modalities, MRI and ultrasound, for diagnosing carotid stenosis. She suggests that MRI holds great promise to serve as a cost effective test for carotid stenosis as well as a tool for assessing vessel health and plaque composition that would provide important information for patient management decisions.




Stay tuned, next Sylvia Urbanik will be talking about cost effectiveness…

See you in the blogosphere,

Pascal Tyrrell

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Research Opportunity Program: What Is Carotid Stenosis and How Are We Treating Affected Patients?

ROP Research Forum March 5th, 2015 – Alana Man

Alana Man is a second year University of Toronto student pursuing a specialist in Bioinformatics and Computational Biology and a major in Immunology. She was a Research Opportunity student last summer with MiVIP (see here) and recently represented us at the March 5th, 2015 ROP research forum.

Alana’s project focused on care for patients with carotid stenosis in Toronto, Ontario, Canada. She looked at the different factors contributing to access to diagnostic testing such as procedure costs, wait times, and the differences between available imaging modalities and explores whether MRI could be the diagnostic test of choice over DUS for people at increased risk of carotid stenosis.

Well done, Alana!




Stay tuned, next Helena Lan will be comparing MRI and DUS…




See you in the blogosphere,




Pascal Tyrrell

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MiWord of the Day Is… PET scan!

 

Peanuts. What a great story. The most popular and influential comic strip in history. Snoopy was my first stuffed animal growing up. He still lives with my parents. So what is a PET scan anyway? I don’t recall ever seeing the picture above in any of the Peanuts cartoon strips.





Positron emission tomography (PET) is somewhat of a special medical imaging modality in that it brings together two different technologies from different times. Let me explain. Back in the early 1930s, George Hevesy was a young Hungarian physicist who developed biologically safe and useful radioactive tracers that could be ingested or incorporated into the body in some way.  Physicians would then manually locate where these radioactive tracers had gone in the body by using a Geiger counter at first and then later using special cameras (Kuhl‘s photoscan) to produce a crude emission image. 



So, how do we get cool pictures like these ones?  Well we would have to wait another 25 years after the development of radioactive tracers by Hevesy for the start of construction of instruments able to not only detect these radioactive sources in the body but to produce tomographic pictures.


It won’t be until the mid 1970s that PET – as we know it today – would be born. Essentially, a patient receives a emissions scan (PET) and a CT (we talked about that here) or MRI (we talked about that here) scan at the same time. The two scans are then merged together thanks to highly specialized computers (see the pictures in the middle frames). Voila! PET. 



PET is both a medical and research tool. Most often used in clinical oncology (medical imaging of tumors and the search for metastases), it is also important in clinical diagnosis of certain diffuse brain diseases such Alzheimer’s disease and other types of dementia.


Relax your brain a little listening to Radioactive by Imagine Dragons and don’t forget the fun part (see the rules here), using PET scan in a sentence by the end of the day:

Serious: Hey Bob, did you know that much of the success of the PET scan is due to the development of the radiopharmaceutical FDG (deoxyglucose) that lead the way to the characterization of Parkinson’s and Huntington’s disease?

Less serious: I can’t believe they developed yet another PET scan. Wasn’t the CAT scan enough?

See you in the blogosphere,

Pascal Tyrrell








 

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Walk Like an Egyptian!

So, in my last post I talked a little about Mesopotamian medicine (see here). I am certain many of you were thinking: “What? Should he not be talking about ancient Egypt?”. Well, of course, you are right – kind of… 


Egypt rose under the pharaohs during the same period as the Mesopotamian kingdoms (from about 3000 BC). They were known for their crazy ambition and technological prowess. Their medicine was very similar to that of the Mesopotamians in that it was influenced strongly by superstition  and religious beliefs. They too had three types of healers: the swnu who practiced medicine, and, of course, the priests and the sorcerers…




One of the reasons that ancient Egyptian medicine had a greater influence on modern medicine was that they were very good at documenting and archiving their work. The Ebers papyrus (c. 1550 BC) was their principal medical document that measured over 20 meters long (it is a scroll after all) and is the oldest surviving medical book. 




The Egyptians believed we were all born healthy but were susceptible to disorders caused by demons or by intestinal putrefaction. So the importance of eating your fruits and veggies was started way long ago! They also compared our vascular network to that of the River Nile and its canals and, therefore, it was important to keep the flow free from obstructions (see here for another interesting comparison!). Though they did not appreciate vascular plaques (atheroma) at the time they had already started to  figure out the importance of a healthy vasculature. Cool! 










As with Mesopotamia, Egypt’s powerful governance created a good environment for organized medical practice. However, because both regimes were highly codified (implying many strict rules based on religion and superstition that did not allow for discussion and experimentation) it will not be until ancient Greece that the roots of modern medicine will take hold.




Dance around your living room (in private if you must) to Walk Like an Egyptian by The Bangles in order to decompress and…


… I’ll see you in the blogosphere.




Pascal Tyrrell

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MiWord of the Day Is… Mesopotamia!

You are thinking about pursuing studies in medicine. You have enrolled in all the necessary courses at school to qualify you for the grueling application process and you are actively looking for volunteer opportunities. So why the need to be active in your community?


Today, I want to talk a little about the history of medicine. Around 3000 BC (and no I was not alive then if you are wondering) the middle east was a hotbed for civilizations who were in transition from being mainly nomadic to more settled. This “land between the rivers” – Mesopotamia – was ruled by many successive great kingdoms including the Akkadian, Babylonian, and Assyrian empires. Thanks to many archaeological and written remains we have discovered that healing practices indeed existed and were established during these times.


Mesopotamian medicine was predominantly religious and was delivered by a team of healers: the seers who would diagnose based on divination, the exorcists who would expel demons, and finally the physician priests who actually treated the sick mostly with charms, drugs, and some surgical procedures.  OK, so this intensely codified approach (which meant very little opportunity for discussion)  to healing that dominated the Mesopotamian kingdoms would not be able to adapt or improve much over time and would ultimately not contribute much to the Greek rational medicine that would come a later and evolve into today’s medicine. 


So why is it important? For two reasons:


Firstly, by understanding the history of medicine you will better appreciate the importance of your role as a physician in your community – regardless if you are a primary care physician on the front line or a radiologist who works in the back ground. What is important is to feel connected and part of your community.


Secondly, it is interesting to see that though Mesopotamian medicine recognized very early on that factors like cold, alcohol, and unhygienic conditions affected health, they were enable to advance and evolve their medicine as Ancient Greece did through ongoing experimentation and discussion. Moral of the story? Medical research rocks!




Do you remember the Babylon 5 series? It came many, many, many years later! Have a peek to decompress and…


… I’ll see you in the blogosphere.




Pascal Tyrrell



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Who is Going to the Karolinska Institute this Summer? Helena Lan Is, That’s Who!!!!










The Karolinska Institutet is one of the world’s leading medical universities and is located in Stockholm, Sweden. Did you know that in 1895 Alfred Nobel appointed the Karolinska Institutet to annually award the Nobel Prize in medicine or physiology? Now you do.

So, you may have read my previous post about “Connectory”. Well today I want to talk to you about one of my Research Opportunity Program students at the University of Toronto, Helena Lan. Not only was she a star student with me last summer (see her timeline post here) but she has continued on with our MiVIP group contributing to a systematic review on research methodology and biostatistics in medical imaging (stop rolling your eyes, it IS an interesting topic!).


Well she just found out that that she has been invited to work at the Karolinska Institute this summer as part of the Summer Research Abroad Program at the University of Toronto which is sponsored by the the Centre for International Experience. WOW!!!







Her supervisor will be Dr. Sofia Johansson, an assistant professor at Karolinska Institutet. Her research is focused on natural killer cell biology. You can find her research interests here.

Want to know about what natural killer cells do as part of our innate immune system? Watch this cool video.












Cool right? Well, I enjoyed it anyway. Maybe you need to watch Mr Brightside by The Killers to recover and…

… I’ll see you in the blogosphere.
PS: Congratulations Helena!!!

Pascal Tyrrell

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Who’s in Agreement?

So, let’s say you have invited everyone over for the big game on Sunday (Superbowl 49) but you don’t have a big screen TV. Whoops! That sucks. Time to go shopping. Here’s the rub: which one to get? There are so many to chose from and only a little time to make the decision. Here is what you do:


1- call your best friends to help you out
2- make a list of all neighboring electronics stores 
3- Go shopping!


OK, that sounds like a good plan but it will take an enormous amount of time to perform this task all together and more importantly your Lada only seats 4 comfortably and you are 8 buddies.


As you are a new research scientist (see here for your story) and you have already studied the challenges of assessing agreement (see here for a refresher) you know that it is best for all raters to assess the same items of interest. This is called a fully crossed design. So in this case you and all of your friends will assess all the TVs of interest. You will then make a decision based on the ratings. Often, it is of interest to know and to quantify the degree of agreement between the raters – your friends in this case. This assessment is the inter-rater reliability (IRR). 


As a quick recap, 


Observed Scores = True Score + Measurement Error


And


Reliability = Var(True Score)/ Var(True Score) + Var(Measurement Error)


Fully crossed designs allow you to assess and control for any systematic bias between raters at the cost of an increase in the number of assessments made. 


The problem today is that you want to minimize the number of assessments made in order to save time and keep your buddies happy. What to do? Well, you will simply perform a study where different items will be rated by different subsets of raters. This is a “not fully crossed” design! 


However, you must be aware that with this type of design you are at risk of underestimating the true reliability and therefore must, therefore, perform alternative statistics.


I will not go into statistical detail (today anyway!) but if you are interested have a peek here. The purpose of today’s post was simply to bring to your attention that you need to be very careful when assessing agreement between raters when NOT performing a fully crossed design. The good news is that there is a way to estimate reliability when you are not able to have all raters assess all the same subjects.


Now you can have small groups of friends who can share the task of assessing TVs. This will result in less assessments, less time to complete the study, and – most importantly – less use of your precious Lada! 


Your main concern, as you are the one to make the purchase of the TV, is still: can you trust your friends assessment score of TVs you did not see? But now you have a way to determine if you and your friends are on the same page!




Maybe this will avoid you and your friends having to Agree to Disagree as did Will Ferrell in Anchorman…




Listen to an unreleased early song by Katy Perry Agree to Disagree, enjoy the Superbowl (and Katy Perry) on Sunday and…


…I’ll see you in the blogosphere!




Pascal Tyrrell

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The story behind Connectory…

So, you are reading our blog thinking Pascal is a nut – that much is clear – but what of all the students plugged into his group? Are they nuts too?


Well maybe, but today I am going to talk to you about the group of four (not the group of seven) who started small and grew to be Connectory. John, Maria, Natasha, and Roger met in a graduate course at the University of Toronto and decided to work together on a project about innovation. That’s when they met me, joined “the program”, and got busy! Starting any endeavour from scratch is no easy task. All four had never met before, all came from very different academic backgrounds, and though their initial project was for “credit” the rest was on their own time.


There were some rough times at first but with perseverance comes success and Connectory was born and is just finishing up its first project as a new start-up business. Wow! 


Essentially Connectory is a data management solutions software development consulting group that operates in the healthcare space. Check out their webpage here.


Ok, so what? Well this post is not only to congratulate these four on a job well done but also to encourage you to do the same. One thing is for sure: if you don’t try you will not succeed – ever. My programs are all about learning, trying new stuff, benefiting from your successes as well as your failures, and wait for it… giving back. Yup as Uncle Ben said in Spiderman: “With great power comes great responsibility“. 


Just wanted to share a good story from our group with you today.




Listen to Bulletproof by La Roux to get pumped and…


… I’ll see you in the blogosphere!




Pascal Tyrrell

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Happy Late New Year 2015!!!

The Moody Tree



Ok, so I may have taken a longer break than I should have. Where was I you ask? I was enjoying some R&R with my family. My kids are at great ages – 15, 11, and 6. Then, of course, when I got back to my desk – whammo! The deluge of work. This morning, as I sat on the GoTrain on the way into Toronto, I thought of you and happily sat down to write my first post of 2015.


First, a thank you for your readership. We are soon approaching our first anniversary (next month) and my programs (MiVIP and MiB) and this blog are chugging along famously… all because of you!



Chicago Bean

Next, a funny story to explain the picture above. When I attended the RSNA last December (see my post here on this event) I brought along my old film camera for fun as I enjoy photography and decided to reminisce a little. To your right is a picture of the Chicago skyline reflected on the “Bean“. See me?


I hadn’t developed film in so long that I almost ruined it – in my laundry room between all of my family’s clothes, the ironing board, buckets, detergents… Anyway, I also had with me my trusted digital for snaps and one evening I was invited to a function at my boss’ hotel and he said to me:”Let me know what you think of the Christmas lights on the trees in front the hotel on your way in”. Alan Moody is an uber-radiologist, the chair of our department, and loves imaging the carotid arteries. As our minds often operate on the same wave lengths, I took the picture and voila – the Moody Tree was born!


There is no end to the fun we have here in the Department of Medical Imaging…



Even though this is not a “MiWORD” post how about you wish a belated Happy New Year to someone you have not been in touch with yet? Send them a quick text or better yet, send them the link to this post and tell them to visit the Moody Tree next time they are in Chicago during the holidays…


See you in the blogosphere,




Pascal