Duke Research Blog

Following the people and events that make up the research community at Duke.

Category: Biomedical Engineering (Page 2 of 7)

Girls Get An Eye-Opening Introduction to Photonics

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Demonstration of the Relationship between Solar Power and Hydrogen Fuel. Image courtesy of DukeEngineering.

Last week I attended the “Exploring Light Technologies” open house hosted by the Fitzpatrick Institute for Photonics, held to honor International “Introduce a Girl to Photonics” Week. It was amazing!

I was particularly enraptured by a MEDx Wireless Technology presentation and demonstration titled “Using Light to Monitor Health and View Health Information.” There were three “stations” with a presenter at each station.

At the first station, the presenter, Julie, discussed how wearable technologies are used in optical heart rate monitoring. For example, a finger pulse oximeter uses light to measure blood oxygen levels and heart rates, and fitness trackers typically contain LED lights in the band. These lights shine into the skin and the devices use algorithms to read the amount of light scattered by the flow of blood, thus measuring heart rate.

At the second station, the presenter, Jackie, spoke about head-mounted displays and their uses. The Google Glass helped inspire the creation of the Microsoft Hololens, a new holographic piece of technology resembling a hybrid of laboratory goggles and a helmet. According to Jackie, the Microsoft Hololens “uses light to generate 3D objects we can see in our environment.”

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Using the Microsoft Hololens. Image courtesy of DukeEngineering.

After viewing a video on how the holographic technology worked, I put on the Microsoft Hololens at the demonstration station. The team had set up 3D images of a cat, a dog and a chimpanzee. “Focus the white point of light on the object and make an L-shape with your fingers,” directed Eric, the overseer. “Snap to make the objects move.” With the heavy Hololens pressing down on my nose, I did as he directed. Moving my head moved the point of light. Using either hand to snap made the dog bark, the cat meow and lick its paws, and the chimpanzee eat. Even more interesting was the fact that I could move around the animals and see every angle, even when the objects were in motion. Throughout the day, I saw visitors of all ages with big smiles on their faces, patting and “snapping” at the air.

Applications of the Microsoft Hololens are promising. In the medical field, they can be used to display patient health information or electronic health records in one’s line of sight. In health education, students can view displays of interactive 3D anatomical animations. Architects can use the Hololens to explore buildings. “Imagine learning about Rome in the classroom. Suddenly, you can actually be in Rome, see the architecture, and explore the streets,” Jackie said. “[The Microsoft Hololens] deepens the educational experience.”

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Tour of the Facilities. Image courtesy of DukeEngineering.

Throughout the day, I oo-ed and aw-ed at the three floors-worth of research presentations lining the walls. Interesting questions were posed on easy-to-comprehend posters, even for a non-engineer such as myself. The event organizers truly did make sure that all visitors would find at least one presentation to pique their interest. There were photonic displays and demonstrations with topics ranging from art to medicine to photography to energy conservation…you get my point.

Truly an eye-opening experience!

Post by Meg Shiehmeg_shieh_100hed

Fostering a Collaborative Research Environment in Peru

We are told time and time again that Duke is a global university, one that transcends borders and takes interdisciplinary education to the next level.

On Monday, I was able to experience this international mindset firsthand at the Peru Health Symposium, a conference that celebrated a decade of culminating research efforts by Duke in Peru.

The symposium was organized by Dr. William Pan, a professor of Global Environmental Health at Duke who has worked on many research projects in Peru ranging from reproductive health to tuberculosis. In his opening remarks, Pan said the trademark interdisciplinary nature of Duke has allowed it to succeed as a research institution in Peru, along with its affiliation to pioneers in Peruvian health/environmental research, like John Terborgh.

“We are standing on the shoulders of giants,” said Pan. During the first panel, several research projects were presented.

Field Work in Peru

Helena Frischtak conducting research with Peruvian children in the field.

Helena Frischtak, a 4th year medical student at UVA and former Doris Duke Fellow spent a year studying the neurological effects of mercury exposure on children. She performed basic neurological exams, along with cognitive tests amongst 5-11 year-old children, and preliminary data suggests potential impacts of mercury exposure on cognitive development.

Marlee Krieger of the Center for Global Women’s Health Technologies presented a cervical cancer treatment that brings colposcopy into the primary care setting. When one is screened for cervical cancer, a pap smear is first conducted and if abnormalities are detected, a colposcopy is performed and tissue is biopsied from the cervix. This multiple-step process is tedious, and the number of patients that return for the colposcopy often declines. By combining the steps into one visit and performing it with a simpler and cheaper device, testing efficiency has increased.

Maria Lazo Porras of Cayetano Heredia University (Lima’s prominent medical university) presented findings on the effects of migration from rural to urban regions on chronic disease. Her findings suggest a correlation between urbanization and obesity, but provided surprising results that indicate higher rates of hypertension and diabetes in rural communities.

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Illegal mining scars the Amazon’s lush forests and flushes mercury runoff into streams.

Students doing research in the Amazon presented posters of their findings to faculty members of the Nicolas School and DGHI.

The main theme resonating throughout the conference was the need for collaboration not only to address public/environmental health concerns, but to organize symposiums like this one. The culmination of efforts by the Center for Latin American and Caribbean Studies (CLACS), DGHI, and the Nicholas School have fueled the Peru project’s palpable success.

Below is the link to the documentary shown at the symposium:

http://www.daughterofthelake.pe/ – “Hija de la Laguna” (Daughter of the Lake), 2015. The documentary tells the story of how a Peruvian woman used her powers to stop illegal mining from destroying the lake in her community; a lake that to her, represents her mother’s spirit.

lola_sanchez_carrion_100hedPost by Lola Sanchez-Carrion

Walla Scores Grand Prize at 17th Annual Start-Up Challenge

The finalists of Duke’s 17th Annual Start-Up Challenge have found time between classes, homework, and West Union runs to research and develop pitches aiming to solve real-world problems with entrepreneurship. The event, hosted last week at the Fuqua School of Business, featured a Trinity alum as the keynote speaker. Beating out the other seven start-up pitches for the $50,000 Grand Prize was Walla, an app founded by Judy Zhu, a Pratt senior.

Judy Zhu and the Walla team pose with their $50,000 check, which is giant in more ways than one.

Judy Zhu and the Walla team pose with their $50,000 check, which is giant in more ways than one.

Walla aims to create a social health platform for college students by addressing widespread loneliness and creating a more inclusive campus community. The app’s users post open invitations to activities, from study groups to pick-up sports, allowing students to connect over shared interests.

Walla is closely tied with Duke Medicine by providing data from user activity to medical researchers. User engagement is analyzed to supply valuable information on mental health in young adults to professionals. The app currently features 700 monthly active users, with 3000 anticipated within the next month, and many more as the app opens to other North Carolina colleges.

Tatiana Birgisson returned to Duke to talk about her own experiences creating a business while an undergrad that won the Start-Up Challenge in 2013. Birgisson’s venture, MATI energy drink, was born out of her Central Campus dorm room and, through the support of Duke I&E resources, became the major energy drink contender it is today, as a healthy alternative to Monster or Red Bull.

The $2,500 Audience Choice award went to Ebb, an app designed to empower women on their periods by keeping them informed of physical and emotional symptoms throughout the course of their cycles, and creating a community through which menstruating women can receive support from those they choose to share information with.

Tatiana Birgisson won the 2013 startup challenge with an energy drink brewed in her dorm room, now sold as MATI.

Tatiana Birgisson won the 2013 startup challenge with an energy drink brewed in her dorm room, now sold as MATI.

Other finalists included BioMetrix, a wearable platform for injury prevention; GoGlam, an application to connect working women with beauticians in Latin America; Grow With Nigeria, which provides engaging STEM experiences for students in Nigeria; MedServe; Tiba Health; Teraphic.

This year’s Start-Up Challenge was a major success, with innovative entrepreneurs coming together to share their projects on changing the world. Be sure to come out next year; I’ll post an invite on Walla!

devin_nieusma_100Post by Devin Nieusma

Duke Robotics Gets an Arm and a Leg Up

There is a robot learning to be a nurse in the School of Nursing. And that’s not even the most interesting robotics project on Duke’s campus!

Duke’s newly formed Robotics Group showed off a wide range of projects underway March 28, during the first annual Duke Robotics Student Symposium. More than 25 speakers from four different universities and one industry-leading company took turns giving TED-style talks.

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Assistant professor of nursing Ryan Shaw (Right) explains the robotic nursing platform to visitors during Monday’s robotics student symposium.

The day kicked off with a look at work being done at Aurora Flight Sciences which included videos of planes designed for human pilots being flown autonomously by the company’s “C3PA” hardware and software.

Faculty from Duke, NC State, NCCU and Clemson then took turns describing the work of their own labs, before breaking to visit the robotic nurse-in-training.

Kris Hauser, one of Duke’s new robotics professors, described the hurdles they’re working to overcome on the robo-nurse, such as pressure sensors that are too easily broken by robotic hands, flexible gears to ensure human safety that also make it impossible to know precisely where a limb will move, and human operators struggling to control multiple appendages in three dimensions in real-time.

Still, Hauser and his funders from the NIH hope that the robotic platform could eventually be used to treat patients in areas with dangerous disease outbreaks or in rural outposts with too few doctors.

The day wrapped up with Duke students talking about their own projects, with no shortage of interesting topics: Medical devices programmed to automatically zap tumors with lasers; tarantula-like robots designed to scale sheer faces of artificial and natural rock; drone systems developed for monitoring elephants in African refuges.

And, of course, the work being done to ensure tomorrow’s autonomous cars don’t run into one another — or anything else for that matter. Learn more about these projects here. 

The day’s take-away message? Despite our short history, there’s a ton going on in the Duke Robotics group.

Ken KingeryGuest Post by Ken Kingery, Pratt School of Engineering

The Future of 3D Printing in Medicine

While 3D printers were once huge, expensive devices only available to the industrial elite, they have rapidly gained popularity over the last decade with everyday consumers. I enjoy printing a myriad of objects at the Duke Colab ranging from the Elder Wand to laptop stands.

One of the most important recent applications of 3D printing is in the medical industry. Customized implants and prosthetics, medical models and equipment, and synthetic skin are just a few of the prints that have begun to revolutionize health care.

3D printed prosthetic leg: “customizable, affordable and beautiful.”

Katie Albanese is a student in the Medical Physics Graduate Program who has been 3D printing breasts, abdominal skeletons, and lungs to test the coherent scatter x-ray imaging system she developed. Over spring break, I had the opportunity to talk with Katie about her work and experience. She uses the scatter x-ray imaging system to identify the different kinds of tissue, including tumors, within the breast. When she isn’t busy printing 3D human-sized breasts to determine if the system works within the confines of normal breast geometries, Katie enjoys tennis, running, napping and watching documentaries in her spare time. Below is the transcript of the interview.

How did you get interested in your project?

When I came to Duke in 2014, I had no idea what research lab I wanted to join within the Medical Physics program. After hearing a lot of research talks from faculty within my program, I ultimately chose my lab based on how well I got along with my current advisor, Anuj Kapadia in the Radiology department. He had an x-ray project in the works with the hope of using coherent scatter in tissue imaging, but the system had yet to be used on human-sized objects.

Could you tell me more about the scatter x-ray imaging system you’ve developed?

Normally, scatter in a medical image is actively removed because it doesn’t contribute to diagnostic image quality in conventional x-ray. However, due to the unique inter-atomic spacing of every material – and Bragg’s law – every material has a unique scatter signature. So, using the scattered radiation from a sample (instead of the primary x-ray beam that is transmitted through the sample), we can identify the inter-atomic spacing of that material and trace that back to what the material actually is to a library of known inter-atomic spacings.

Bragg diffraction: Two beams with identical wavelength and phase approach a crystalline solid and are scattered off two different atoms within it.

How do you use this method with the 3D printed body parts?

One of the first things we did with the system was see if it could identify the different types of human tissue (ex. fat, muscle, tumor). The breast has all of these tissues within a relatively small piece of anatomy, so that is where the focus began. We were able to show that the system could discern different tissue types within a small sample, such as a piece of excised human tissue. However, in order to use any system in-vivo, which is ideally the aim, you have to determine whether or not it works on a normal human geometry. Another professor in our department built a dedicated breast CT system, so we used patient scans from that machine to model and print an accurate breast, both in anatomy and physical size.

 

What are the three biggest benefits of the x-ray imaging system for future research? 

Main breast phantom used and a mammogram of that phantom with tissue samples in it

Main breast phantom used and a mammogram of that phantom with tissue samples in it

Coherent scatter imaging is gaining momentum as an imaging field. At the SPIE Medical Imaging Conference a few weeks ago in San Diego, there was a dedicated section on the use of scatter imaging (and our group had 3 out of 5 talks on the topic!). One major benefit is that it is noninvasive. There is always a need for a noninvasive diagnostic step in the medical field. One thing we foresee this technology being used for could be a replacement for certain biopsy procedures. For instance, if a radiologist finds something suspicious in a mammogram, a repeat scan of that area could be taken on a scatter imaging system to determine whether or not the suspicious lesion is malignant or not. It has the potential to reduce the number of unnecessary invasive (and painful!) biopsies done in cancer diagnosis.

Another thing we envision, and work has been done on this in our group, is using this imaging technique for intra-operative margin detection. When a patient gets a lumpectomy or mastectomy, the excised tissue is sent to pathology to make sure all the cancer has been removed from the patient. This is done by assessing whether or not there is cancer on the outer margins of the sample and can often take several days. If there is cancerous tissue in the margin, then it is likely that the extent of the cancer was not removed from the patient and a repeat surgery is required. Our imaging system has the potential to scan the entirety of the tissue sample while the patient is still open in the operating room. With further refinement of system parameters and scanning technique, this could be a reality and help to prevent additional surgeries and the complications that could arise from that.

What was the hardest or most frustrating part of working on the project? 

We use a coded aperture within the x-ray beam, which is basically a mask that allows us to have a depth-resolved image. The aperture is what tells us where the source of the scatter came from so that we can reconstruct. The location of this aperture relative to the other apparatus within our setup is carefully calibrated, down to the sub-millimeter range. If any part of the system is moved, everything must be recalibrated within the code, which is very time-consuming and frustrating. So basically every time we wanted to move something in our setup to make things better or more efficient, it was like we were redesigning the system from scratch.

 What is your workspace like?

Katie and the team at the AAPM (American Association of Physicists in Medicine) conference from this past summer in Anaheim, CA where she presented in a special session on breast imaging. From left to right: Robert Morris (also in the research lab and getting his degree in MedPhys), Katie, Dr. James Dobbins III (former program director and current Associate Vice Provost for DKU) and Dr. Anuj Kapadia, my advisor and current director of graduate studies in the program

Katie presented in a special session on breast imaging at the American Association of Physicists in Medicine conference this past summer in Anaheim, CA. From left to right: Robert Morris, also working in the lab; Katie; Dr. James Dobbins III, former program director and current Associate Vice Provost for Duke-Kunshan University; and Dr. Anuj Kapadia, Katie’s advisor and current director of graduate studies.

We have a working experimental lab within the hospital. It looks like any other physics lab you might come across- messy, full of wires and strange electronics. It is unique from other labs within the Medical Physics department because a lot of research that is done there focuses on image processing or radiation therapy treatment planning and can be done on just a computer. This lab is very hands-on in that we need to engineer the system ourselves. It is not uncommon for us to be using power tools or soldering or welding.

What do you like best about 3D printing? 

3D printing has become such a great community for creativity. One of my favorite websites now, called Thingiverse, is basically a haven for 3D printable files of anything you could ever dream of, with comments on the best printing settings, printers and inks. You can really print anything you want — I’ve printed everything from breasts, lungs and spines to small animal models and even Harry Potter memorabilia to add to my collection. If you can dream it, you can print it in three dimensions, and I think that’s amazing.

 

Anika_RD_hed100_2By Anika Radiya-Dixit

 

An Adventure Abroad in Brain-Machine Interfaces

11080630_10205422939006642_2749326952690554776_o copyMatthew McCann, Pratt ’16, spent his summer translating thoughts into movements.

A biomedical engineering and mathematics major, the Duke senior contributed to work in the field of prosthetics by creating a brain-machine interface that senses different brain waves of a subject and converts them into movements of a mechanical hand.

McCann, who had never traveled to Europe, let alone lived there for three months, took his foreign adventure one step further and pursued cutting-edge research in Rand Almajidy’s biomedical engineering lab in Germany. McCann was paired with the University of Freiburg for a Research Internship in Science and Engineering by the German Academic Exchange Service.

McCann combined two prominent biomedical techniques, tri-polar concentric electroencephalograms (tEEG) and near-infrared spectroscopy (NIRS), to pick up the brain activity of his subjects. EEGs are the typical devices one pictures when imagining recording brain activity: electrodes stuck all over a subject’s skull to pick up neuron firing when particular brain regions are active.

NIRS is a novel way of measuring brain activity. A common application of NIRS is in the pulse oximeter, or the plastic clip-like contraption doctors place on your finger to measure pulse and blood oxygenation. McCann used NIRS to measure the blood flow in different regions of the subject’s scalp. Different patterns of blood flow indicated dynamic brain activity.

Based on data obtained from these two techniques, McCann categorized brain activity into three specific intentions: thinking about moving the right hand, thinking about moving the left hand, and thinking about moving the feet. Each different intention to move was then connected with moving one finger of a mechanical hand. An example of the hand moving in response to different intentions is shown below (at 8x speed):

McCann’s major challenges in the project were processing complicated EEG signals and removing noise from these signals in order to correctly classify each of the movement intentions. He worked with vast amounts of training data from subjects who had practiced focusing acutely on each of the movements.

He ultimately isolated the specific frequency bands whose power was modulated most drastically during the three movement intentions he was targeting. These frequency bands served as the basis for his machine-learning algorithm, which matched known data the subjects had been trained to produce with unknown thoughts about movement.

After developing his algorithm, McCann tested it on unknown data, in which subjects thought about moving their right hand, their left hand, and their feet in some arbitrary sequence. McCann’s algorithm ultimately obtained impressive accuracy of up to 80% when categorizing unknown thoughts about movements.

Through his research, McCann demonstrated the feasibility of rapidly creating functional prosthetics from simple materials and only open-source software. His prosthetic hand proves promising to medical innovation, as it represents a non-invasive, functional brain-machine interface. Ultimately, his success sheds optimism on the future of prosthetics.

Learn more about McCann and his projects on his website.

professionalpictureby Olivia Zhu

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