April 2008 Newsletter

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.”

by Gordy Slack

In many emerging economies, like India’s, advances in telemedicine can ensure that big-city healthcare is available even at the outskirts of town. But what about the millions of people who live beyond the outer reaches, where the “tele” in telemedicine does not yet reach?

UC Berkeley Professor Eric Brewer’s CITRIS-supported Technology and Infrastructure for Emerging Regions (TIER) project has found a way to bring broadband wireless to villages that, until now, have been off the tele-communication map. By modifying simple and readily available wi-fi technologies, the group has linked tiny local eye clinics in the southern India state of Tamil Nadu to bigger clinics, like the Aravind Eye Hospital at Theni.

In the past three and half years, the project has grown from just one clinic and one hospital to include now thirteen clinics linking up to three different hospitals. The clinics are providing videoconferences with eye doctors for about 3,000 rural patients a month, says Sonesh Surana, a computer science graduate student at UC Berkeley who has been involved with the project since its inception in late 2004.

If it were not for the remote clinics, very few of those patients would get any eye care at all. “Most of these people have never had a eye check-up before this” says Surana. “Having a doctor in a white coat on the other end of the videoconference actually looking them in the eye and paying attention to their ailments makes patients feel included and respected,” he says. And after such personal contact, the patients are much more likely to follow the advice the doctor gives.

In only about ten percent of the cases does that advice require a trip into town for surgery or some other procedure. Most of the other cases call for simpler prescriptions that can be filled by the local high-school-educated girls trained to run the village outposts, avoiding expensive and disruptive day-long trips into town for most of the clinics’ patients. Those who require cataract surgery or other procedures make appointments during the videoconference. They can also do on-line follow-up interviews after their surgery, saving more expensive and time consuming trips.

The TIER group used Wi-Fi cards based on the 802.11 networking standard, just like those found in most laptops. But the 802.11 standard typically limits that technology’s range to a “hotspot” reaching only about 200 feet, and the signal is broadcast out equally in all directions. By modifying the software and focusing the signal from routers with high-gain directional antennas, the group extended and narrowed its reach while retaining decent transmission speed. The networks they have set up can extend dozens of kilometers and operate at speeds of up to six or seven megabits per second.

The connection does require a direct line of site between stations, but obstacles can be bypassed by adding a relay on a tower, says Rabin Patra, another student of Brewer’s and a TIER member. Theoretically, adding relay stations could extend the connection to reach hundreds of kilometers, but the end-to-end latency grows with each relay and would eventually grow too long to make videoconferencing effective. The various nodes in the network can communicate with each other through the central hub, however, and this allows people in the participating villages to communicate with one another.

The system is reliable and fast enough for both videoconferencing and the transmission of clear ophthalmologic images and other data. It can extend into areas with no cell phone coverage, no cable, no wires, says Surana. All those things are key, but what is perhaps most extraordinary about this technology is its price.

The onetime Wi-Fi equipment cost amounts to only $800 per link; after setup the system is very inexpensive to operate. It uses only about seven watts of electricity, which can come from a variety or sources, including solar. Once capital equipment cost is amortized over the five years, the cost for this vital service comes to about only $200 per year.

The TIER researchers work with the Intel Research Berkeley lab team on the Aravind Eye Hospitals project through an open collaborative research agreement between Intel and UC Berkeley.

After three years, the system is working smoothly; local villagers are able to repair and maintain the networks on their own. But the TIER group is still working on improvements. Surana, for instance, is trying to make the system more reliable and robust.

A number of different problems can take the system down. But to someone working at the local clinic or at the hospital, they all look the same: no connection. Surana is developing built-in mechanisms to let users on both ends know when the system is limping, so steps can be taken beforehand to avert a fall. And he is also developing ways to let users know if, say, the system is down because of a simple power failure, or if the problem is something else—and susceptible to fixing.

One option, in areas where service is available, would be to employ cell phones as a backchannel; if the power goes off or if something else goes wrong with the connection, the cell phone could send a signal to the nodes and base station to let them know what was happening. “Cell phones are low bandwidth and high cost,” says Patra. “But, for very short and infrequent calls, they could be affordable and reliable sources of very valuable information.”

Patra is also working with another student, Sergiu Nedevschi, on further optimizing the system’s efficiency and speed. Right now, both ends of the link are sending and receiving data packets in one-to-one ratios. So that the signals don’t collide in the back-and-forth, one end transmits for a few milliseconds and then receives for a few milliseconds. These pulses are precisely timed and synchronized so the two ends of the connection are coordinated. But the direction of data flow isn’t always so balanced; at times one end does a lot more sending than receiving and at other times the ratio may be reversed. So, Patra is developing software that can sense the ratio of sent data to received data and shift the amount of sending versus receiving time allocated to fit those ratios. Their simulations predict that they improve efficiency by between 25 and 100 percent, depending on the traffic pattern and network topology.

The Aravind Eye Hospital aims to have the most affluent one-third of its patients subsidize care for the poorer two-thirds, so keeping costs low for subsidized patients is key to its success. The cost efficiency of the wireless system enables the hospital’s innovative subsidy structuring to work.

The network exposes rural patients to the clinic, on the one hand, and allows most of them to avoid traveling to town on the other. The program has other side effects, too. Training local young people to administer basic eye care has increased overall awareness of health issues in the villages, says Patra. And the networks themselves can be used to bring movies and other entertainment and information into the remote areas.

A new federal Indian program aims to set up 100,000 information kiosks in India’s rural villages. For those areas beyond the reach of traditional phone lines and other wireless service, TIER’s low cost, broad-band wi-fi may be the strongest, cheapest method of connecting those kiosks to the broader world. TIER’s wi-fi is being used in projects in Africa and the Philippines as well, and could easily be applied in remote areas in the US, too, says Patra. A government agency in California is monitoring forests for fires using long-distance Wi-Fi.

“The US is pretty well wired,” Patra says, “but sometimes we need a way to go that final ten or twenty miles.”

However, even if the system does not spread far beyond its use in the Aravind project, it has been well worth the effort, says Patra.

When asked how many other computer science graduate students can say they have made it possible for 200 more people to see each month, Patra laughs and says the credit goes to the hospitals, not the programmers. “We just filled in the missing link.”