The Grapevine

'Selfie' App Detects Pancreatic Cancer By Measuring Bilirubin Levels In The Eyes

Smartphones have revolutionized more than just the way we communicate: we now use them to read books, pay our bills, and even monitor our health. Mobile technology has become the future of medicine with the development of apps that can detect various health problems before they become visible. Researchers at the University of Washington have created an app that could detect the early signs of pancreatic cancer by simply looking at our eyes.

The app, "BiliScreen," uses a smartphone camera, computer vision algorithms and machine learning tools to detect increased bilirubin levels — reddish yellow pigment formed by the breakdown of red blood cells — in a person's sclera, which is the white part of the eye. Jaundice, the yellow discoloration of the skin, causes a rise in bilirubin levels before it's visible to the naked eye. However, researchers found BiliScreen is able to detect color changes in the eye as people take a selfie.

In the initial clinical study, the app, used in conjunction with a 3D printed box that controls light exposure for the eye, accurately identified cases of concern 89.7 percent of the time in 70 people compared to the current blood test doctors use. This is significant because changes in sclera are normally detected once bilirubin levels are well past cause for concern.

Researchers used BiliScreen by using a smartphone's built-in camera and flash, which collects photos of a person's eye when they take a selfie. A computer vision system is able to automatically and effectively separate the white parts of the eye, which can be helpful for making a diagnosis. The app will then calculate the color information from the sclera; this is based on the wavelengths of light being reflected and absorbed, and correlate it with bilirubin levels using machine learning algorithms.

Aside from a 3D printed box, the team also tested the app with paper glasses printed with colored squares. This was used to help calibrate color. Yet, the researchers found using the app with the 3D printed box led to the best results.

Dr. Jim Taylor, a professor in the UW Medicine Department of Pediatrics, whose father died of pancreatic cancer at age 70, believes this technology shows promise for helping people who have pancreatic cancer catch it in time to have surgery and improve their odds of survival. Currently, pancreatic cancer has a five-year survival rate of 9 percent.

"Pancreatic cancer is a terrible disease with no effective screening right now," said Taylor, in a statement.

BiliScreen could potentially help patients with pancreatic cancer who require frequent bilirubin monitoring. Currently, a blood test is used by doctors to measure bilirubin levels, which is not performed on adults unless there's a cause for concern. Pancreatic cancer patients experience high levels of bilirubin due to the blockage of the common bile duct by a tumor.

The researchers designed the app to be an easy-to-use, non-invasive tool that can help people get early treatment if needed. Only about 10 to 15 percent of pancreatic cancers diagnosed are eligible for surgery. Typically, this cancer is diagnosed at a late stage because it doesn't cause common symptoms like jaundice, weight loss and abdominal pain until the tumor has grown significantly and it becomes too late.

Moreover, BiliScreen focuses on the eyes, specifically the whites of the eyes, which can be more sensitive than skin to changes in bilirubin levels. Changes in sclera tend to be more consistent across people from all races and ethnicities, unlike skin color.

"The eyes are a really interesting gateway into the body -- tears can tell you how much glucose you have, sclera can tell you how much bilirubin is in your blood," said Shwetak Patel, senior author of the study and a professor in computer science and engineering, in a statement.

Previous research has shown smartphone apps can be successful in detecting jaundice in newborns within minutes. When a newborn's skin turns yellow, it's a sign they're are not adequately eliminating bilirubin. The smartphone app "BiliCam" served as a screening tool to determine whether a baby needs a blood test, which is how doctors can detect high levels of bilirubin.

BiliCam cannot replace a blood test, but just like BiliScreen, it can let people know if they should take the next step.

Source: Mariakakis A, Banks MA, Phillipi L et al. BiliScreen: Smartphone-Based Scleral Jaundice Monitoring for Liver and Pancreatic Disorders. Proc. ACM Interact. Mob. Wearable Ubiquitous Technol. 2017.