by Gordy Slack
Dr. Wilbur Lam is accustomed to watching blood very closely. As a pediatric hematologist at UCSF, many of his young patients are undergoing chemotherapy treatment for cancer. If the drugs used to attack their cancer cells kill too many white blood cells, Lam’s patients become vulnerable to infection. If too many red cells are lost, patients become anemic. And if platelets levels dip too far below normal, Lam’s patients can begin to bleed spontaneously.
For these children, frequent trips to the hospital to monitor their blood levels can increase an already huge burden—especially for families living far from their doctors or medical centers. And a blood test visit to a hospital can expose immune-suppressed chemotherapy patients to dangerous pathogens, risking their health to further dangers.
Fortunately, a group of bioengineers at UC Berkeley is developing a simple instrument that could allow Lam’s patients, and millions of others with chronic blood conditions, to easily and inexpensively monitor their blood from home. The device fuses two straightforward technologies—a camera-equipped cell phone and a basic optical microscope—into one powerful tool: a portable microscope that can send annotated images of blood cells to labs or medical centers for analysis.
Before long, Lam hopes, patients will be able simply to prick themselves for a blood sample, insert the sample into the microscope, and push a button to send a microscopic image to a lab. After doing blood counts and other tests, the lab would send relevant information back to the patient and to the patient’s doctor.
“Right away, and from home, chemo patients can see whether or how soon they need a transfusion and how careful they have to be to avoid potential sources of infection,” says Lam.
The idea for the tele-microscope first arose a year and a half ago in UC Berkeley Professor Daniel Fletcher’s Bioengineering 164, an undergraduate class on the optics of microscopes. Fletcher assigned his students to design a microscope lens that could be affixed to an off-the-shelf cell phone.
“When the course was over, we had a good design and realized it could be much more than just an exercise,” says David Breslauer, a bioengineering graduate student who was taking the class and became the student leader on the project. “We realized this could be a very practical and powerful tool in the real world.”
Collaborations with the telemedicine program at UC Davis and with industry partners, as well as with engineers and clinicians, are some of the things that make this project so extraordinary, says Fletcher. Winning a CITRIS white-paper award last year “was a catalyst for many of these collaborations,” says Breslauer, the co-author of the white paper. The project is also supported by the Blum Center for Developing Economies, which has already begun to use cell phones to collect medical data at sites in Africa. Microsoft Research has provided financial support, too.
The device promises not only to improve the lives of patients in the developed world, like Lam’s, but could also bring the benefits of modern medicine to millions of people in developing nations who currently live beyond its reach. In fact, before Fletcher and Breslauer realized its potential applications closer to home, the device was originally conceived as a quick way to get microscopic information about patients in poor remote regions to specialists at inaccessible medical centers. Millions who suffer from malaria, for example, live far from any medical services, says Fletcher, and a device such as this would allow a minimally trained technician in a rural community to take blood samples and quickly get a definitive diagnosis at very low cost.
Not only might the new device help underserved patients to get reliable diagnoses, but it could also help in the implementation and study of broader efforts to combat diseases like malaria. As worldwide anti-malaria projects are backed by the Bill & Melinda Gates Foundation and other major funders, the ability to do good epidemiological studies becomes key, says hematologist Lam, who is also a graduate student in Fletcher’s bioengineering lab at UC Berkeley. For example, to determine if a mosquito-net program is helping to slow the spread of malaria in an area, for example, scientists must first establish the extent of infection there. And the study must be updated periodically to measure progress. The group’s cell-phone microscope will be a powerful and inexpensive data collection tool for these sorts of vital studies.
The microscopes will not be limited to imaging blood cells, however. They could handle such specimens as stool, urine, or saliva, Lam says. Cholera would be diagnosable, as would certain kinds of urinary tract infections, which can be dangerous if left undiagnosed and untreated in young children.
Sickle cell anemia would also be diagnosable via images from the microscope camera, says Lam. And already-diagnosed sickle cell patients could more conveniently monitor their conditions; a sudden drop in red blood cells, for example, is a good predictor of other more serious problems soon to follow for sickle cell patients, says Lam.
Though the project was originally conceived as a way to bring medicine to the underserved, Fletcher and his group realized early on that if the microscope camera was likely to see the commercial light of day, it would have to have a salable application in the developed world first.
“Realistically, if manufacturers are going to invest in the device,” says Fletcher, “there has to be a market first where people can afford to buy it.”
In addition to his engineering expertise, and his experience with blood, Lam has also brought a knowledge of the “very conservative medical establishment’ to the project.
“Doctors do not like to adopt new tools unless there is a very good reason,” Lam says. And they do not adopt them unless they can weave them into their own economic models, either, points out Breslauer. If doctors have an easy way of being compensated for reading images that patients send to them from home, they will have more incentive to adopt the practice.
The group’s plan now is to perfect the prototype (they will begin field testing it over the summer) while developing an economic model for selling it here in the US. Then, once its niche is established, the subsidized technology could be shifted to developing nations.
The unit itself uses a modified cell phone belt-attachment to hold a microscope lens onto the phone. While the current prototype works well and magnifies up to 25X, the final product will have a much shorter lens with twice the magnification, says Breslauer. The current lens demonstrates proof of concept, but it is still too long and vulnerable to be practical. “It is a little like a rifle barrel,” says Breslauer. But it is a vast improvement in size from the first version, which covered an entire tabletop. The final product, after the optics are optimized, will be only a few inches long, will weigh less than a pound, and will probably cost about fifty dollars, says Fletcher.
Fletcher and his colleagues also want to add an internal light source to the device so that it can illuminate samples for still clearer images. In addition, the group is developing software that will protect patient confidentiality while allowing users to annotate the micrographs and to submit them automatically in a standardized format that meshes with other record-keeping formats already in place.
The group hopes to have a device out and in the field within the next year.
“The beauty of this project is that all the pieces were already there,” Lam says. “Cell phones, microscopes, and cameras are ubiquitous in our society as ordinary technologies. But put them together, and you have got something completely new.”