Designs for diagnosis at a distance
Determining the existence of cancer in biopsied tissue presents a major problem to clinics and hospitals, particularly those in locations that lack on-site pathologists.
Determining the existence of cancer in biopsied tissue presents a major problem to clinics and hospitals, particularly those in locations that lack on-site pathologists. Two recent advances in imaging technology have pointed the way to solutions for that problem. One involves the ability to transmit medical data and images via mobile phone. The other uses a virtual microscope system that can e-mail compressed images of electronic slides.
Boris Rubinsky, a professor at the University of California, Berkeley, who also holds a faculty position at the Hebrew University of Jerusalem, explains the problem. “Twenty percent of diseases require medical imaging for treatment, yet two-thirds to three-quarters of the world’s population does not have access to medical imaging,” he says. “Even if an institution like the World Health Organization donates medical imaging devices to those areas, there’s nobody to read them.”
But what if images could be transmitted to central facilities that would automatically process them for medical review? Rubinsky and his colleagues realized that mobile phones, which are often available in underprivileged areas, could carry out that task, at least if the team could adapt the imaging technique.
Separating the components
Conventional medical imaging devices contain data-acquisition hardware, an image-processing system, and an image-display unit. Rubinsky’s group came up with the idea of separating the components. The acquisition device that collects the raw data would, of necessity, remain at the remote doctor’s office, clinic, or hospital. But the complex and expensive hardware and software for data processing and image reconstruction would be located in a central facility capable of serving multiple remote sites. Local medical personnel would use cell phones to transmit unprocessed data gathered on-site to the central server. The server would process the data and return it to the site. There, the image would appear on a mobile phone’s screen for study by the on-site doctor. “An ultrasound device costs about $70,000, but an ultrasound transducer costs about $2,000,” Rubinsky explains. “This concept changes the economy.”
To test the idea, team members built a simple data-acquisition device based on 32 stainless-steel electrodes. They connected the device to a container filled with gel that simulated breast tissue with a tumor. Next, they used the device to collect voltage measurements from the simulated tissue and uploaded the data onto a mobile phone for processing remotely. The processed image, returned to the mobile-phone’s screen, plainly revealed the simulated tumor. Does an image on a cell-phone screen contain enough resolution for local physicians to make accurate diagnoses? “In terms of the number of pixels, it very often has greater resolution than a regular screen,” Rubinsky says. “Resolution is really no problem. You can magnify and study the picture.”
Having proved the concept, Rubinsky and his team are now fielding requests from organizations interested in commercializing the technology. Potential suitors include hospital chains in China, India, and South America, as well as American corporations.
In another advance, a Sino-American collaboration has recently received a U.S. patent for a virtual microscope and associated software that permit medical personnel in remote locations to e-mail electronic slides to pathologists off-site. “Our system has been designed by a pathologist for pathologists,” says Virginia Anderson, a pediatric pathologist at the SUNY Downstate Medical Center in Brooklyn who worked on the project with Jiang Gu, chairman of pathology at Beijing’s Peking University. “We have the capability of scanning the whole slide, but we don’t do that because it’s not necessary. Slide prepared by an experienced pathologist will focus on important areas to make a diagnosis.”
Anderson and Gu developed the device in response to the lack of pathology services in many parts of the world. For example, 600 hospitals in China do not have a pathologist on-site. Clinical trials of the instrument have started in that country. And Chinese company Motic has used the team’s patent to create a microscope with a robotic stage that scans whole slides at various magnifications and creates compressed images for e-mailing. – PG