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Chad Haney
68,690 followers -
I'm the medical imaging, Red Wings, Formula One, Tech guy.
I'm the medical imaging, Red Wings, Formula One, Tech guy.

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Medical visualization, it's what I see and do
I was going to summarize an article about the history of medical visualization that was discussed in MIT Technology Review in 2012.
The Future of Medical Visualisation
http://goo.gl/HnpAQq
However, I think that the #OpenAccess  article that they reference does a good job on its own. It's kind of strange to think of a review of a review of a review article.
From individual to population: Challenges in Medical Visualization
http://arxiv.org/pdf/1206.1148v2

Rather than review the review of the review, I'll add a few comments and answer your questions. So read either the MIT Tech Rev article or the journal article and ask questions. This is an opportunity to talk to a scientist that works in the medical imaging field.

The article mentions multi-modal volume visualization. If you have been following my  #CHMedicalImagingSeries then you know that each imaging technique (modality) has strengths and weaknesses. Combining imaging modalities, like the MRI and CT below of my head, allow you to take advantages of the strengths and minimize the weaknesses. To get the best out of multi-modality imaging you need to be able to fuse the images. The technical term is image registration or some like image co-registration. There is a lot of research in just this technique to make it more automated. One common technique is called mutual information. Our brains can easily tell that the dark material in MRI is bone (e.g. my skull) and it should match the bright material in CT. Mutual information tells the computer to consider that bright could equal dark by normalizing the images first. The principal axes of the objects are also used to register (align/fuse) the two images. For therapy planning, both surgery (cosmetic) and tumor resection/radiation, multi-modality imaging can have a huge benefit. They mention that in 1993 Altobelli used multi-modality imaging to visualize the possible outcome of complicated craniofacial surgery.

Another use of medical imaging visualization is virtual colonoscopy. Visualization tools that you need are surface/volume rendering, skeletonization, and segmentation.
UCSF Radiology: What Virtual Colonoscopy CT Scans Look Like

Surface/volume rendering is just what it sounds like. The data is analyzed and the surface can be identified and displayed with shading and lighting such that it looks 3D. You can make it true 3D with the right equipment (3D glasses, 3D monitor, and software to split the data into left and right views) but that's not essential. It can't be emphasized enough that modern GPUs have made these difficult calculations become trivial. Some of the early animation work and medical image visualization required high end UNIX workstations. Now that same level of visualization can be done with a low-end gaming PC.

Segmentation is also, just as it sounds. There are automated and manual segmentation tools. For example in the heart and skeleton images below, the tissue of interest has been segmented out of the "background" tissue, e.g., the internal organs, muscle, etc. Again, there is research in this technique alone. Our brain can look at a medical image and identify parts of the brain or organs quickly. "Teaching" a computer program to do that automagically is very difficult, especially if there is motion due to breathing. In that case, you may have to use image registration to get rid of the motion blurring first.

Skeletonization is a process of identifying paths. For colonoscopy, that would be teaching the program to traverse the path of the colon. I've done work where we were measuring blood vessel diameters in a pulmonary hypertension model. Skeletonization was used to automatically identify each part of the vascular tree. From there, it was easy for the software to measure each diameter.

The first three images are fused images of a CT and MRI of me. The yellow surface rendered part is from CT as it shows bone (skull) very well. The grey-scale part of the image is MRI which shows soft tissue very well. The rest of the images are from a Toshiba 320 slice CT. In CT technology, a ring of detectors is used capture the signal from the x-ray source. Each ring is called a slice in clinical CT machines. For a while 64 slice was considered the best. Now 256 and 320 slice machines are becoming available. More slices means you can cover a larger area in a shorter amount of time. So highly detailed images of the heart can be acquired without motion artifacts from the beating heart. Likewise for the lungs.

Here's a few older posts that will hopefully help you understand the article.

Medical Imaging 101 pt 1 (http://goo.gl/LTWUf)
Medical Imaging 101 pt 2: CT (http://goo.gl/IHaFw)
Medical Imaging 101 pt 3: MRI (http://goo.gl/UVbiU)
Functional vs. anatomic image (http://goo.gl/UTPK7)
Visible Human project (http://goo.gl/cv2xU)
Eye of Horus post (http://goo.gl/qpxyh)

Image sources other than the above article:
Lung and brain CT images (http://goo.gl/HHhqSJ)

CT Heart (http://goo.gl/eqbFde)
#ScienceSunday  
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Medical Imaging Visualization
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Primal Posture
I plan to investigate a bit more on the work by Esther Gokhale on "primal posture". Here's her TED talk.
https://www.youtube.com/watch?v=k1luKAS_Xcg

It kind of makes sense but I'd like to learn more. I heard this on the radio on the way to work then saw it posted by +Jennifer Freeman
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Today's #JoinInDaily theme by +Johnny Wills is "Leaves!"
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Manistee, MI 2018
My sister's neighbor's friend invited us to join them at Insta Launch campground/marina in Manistee, MI. Most of the campsites are right on the marina which is at the end of the Big Manistee River. The Big Manistee River feeds into Manistee Lake. At the south end of the lake you can access the Little Manistee River.

We have taken Ana kayaking once before and we have been kayaing without her a few times with our new-ish tandem kayak. After talking to one of the owners (they also operate a canoe and kayak rental service), I was convinced that it would be OK to bring Ana kayaking on the Big Manistee River using our Old Town tandem. She had already been canoeing on the Platte River which is nearby.

We drove to my sister's place in Michigan last Thursday evening to cut a couple of hours off the drive north. We got there at 2 AM due to the time difference and a protest that shut down Lake Shore Drive near work (so I couldn't leave early). We got up at 6 AM so that we could kayak after setting up camp. We wanted to maximize our time there because it was basically just a long weekend. We quickly set up and met with the rest of the group who had gone up on Wednesday. We decided to do the Platte River first, which is nice and easy.

Riverside Rental in Honor Michigan are really cool about letting people use their launch site even if you aren't renting from them (we rented canoes from them before, with Ana). Our group was really disorganized. In fact we accidentally drove about 10 miles past the launch site because you have to be careful when typing "riverside rental" into your navigation system. There's too many.

Anyway, we bought sandwiches and had lunch in the shade on the river. Ana couldn't wait and licked my wife's sandwich a few times. Don't worry, it was wrapped in wax paper and we did share some with her. It was a nice ~3 hour paddle. The Platte River ends at Sleeping Bear Dunes which is really pretty. There were a lot of people floating in tubes on the route too. Ana got people's attention a along the route. Kind of strange because there were a few other dogs too. We should have taken a swim at the sandbar in the lake we crossed but the wind was a bit strong and we didn't want to get cold. The French bread pizza foil dinners were yummy that night. I have to figure out how to keep them from burning when the sauce leaks out.

The next day we planned on a 4 hour float on the Big Manistee River. We were trying to find Rainbow Bend access point in the Manistee National Forest. I didn't have good cell reception so I couldn't help. No surprise, it was chaos trying to figure out how to get there. With 9 people and 8 kayaks, it's takes some time getting everything unloaded and ready. It was about 90 °F so people were naturally getting cranky. Once we got going, it was really nice. Ana was a bit fidgetty. We probably have to make a cushion for her. For most of the paddle, my wife mainly didn't paddle and just kept Ana from fidgeting too much. Because the rest of the group was paddling really slow, we decided two people had to paddle so that we could finish before dark and also feed Ana. With two people paddling and Ana behaving, we ended up about 45 minutes ahead of the rest of the group and maybe 20 minutes ahead of my sister.

As far as new camping gear goes, we got Ana a portable crate from Duluth Trading Co. She likes being in her crate at home. She was very content in her portable crate. It's light and folds up nicely. The craftsmanship is a bit poor (it's already starting to develop a hole) but we like it so far. As best I can tell, the mosquitoes didn't bother her. They got me pretty good on my knees and calves even wearing pants. We got a couple of small LED lanterns from Black Diamond that worked well.

When we were driving home, both my kayak and my sister's kayak were pushed to one side by a gust of wind. You can see in the last photo that the front rack is shorter on the driver's side. We drove 10 mph below the limit for about half of the drive because it was too windy. I'm probably going to switch from the J-hook style cradle to a flat four foot mount set up.
Manistee, MI 2018
Manistee, MI 2018
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Wieners Circle has hilarious signs. I walked past this last night and laughed out loud.
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Chicago needs to do the same. There are too many and they make congestion worse.
New York City just voted to cap Uber and Lyft vehicles, and that could make rides more expensive

https://www.cnbc.com/2018/08/08/new-york-city-votes-to-cap-uber-and-lyft-vehicles.html

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A good laugh. How accurate is it +gnostic pasta? LOL.
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Kayaking and camping, Manistee, MI.
Just got back from camping and kayaking in Michigan. I'll post more photos later. Gotta catch up on some work stuffs.
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