At just about every doctor’s visit, you get your temperature, heart rate, and blood pressure measured. But there’s no stethoscope for pain. Patients must express how bad pain is using a 10-point scale or emoji-style chart—the one with faces turning from smiles to frowns. Now a doctor has invented a device to measure the “ouch.”
For years, 17-year-old Sarah Taylor struggled to make doctors understand her pain, first from childhood arthritis and then from fibromyalgia. “It’s really hard when people can’t see how much pain you’re in, because they have to take your word on it and sometimes, they don’t quite believe you,” she says.
Now scientists are peeking into Sarah’s eyes to track how her pupils react when she’s hurting and when she’s not.
“If we can’t measure pain, we can’t fix it,” says Dr. Julia Finkel, a pediatric anesthesiologist at Children’s National Medical Center in Washington who invented the experimental eye-tracking device.
The inability to measure pain is problematic. Doctors have to guess at babies’ pain by their cries and squirms, for example. One person’s number seven pain might be a four to someone more used to serious pain or naturally more pain-tolerant. Patient-to-patient differences make it hard to test whether painkillers really work.
Finkel says some pain-sensing nerves transmit “ouch” signals to the brain along the same pathways that alter the pupils. Her device tracks those reactions.
Some researchers have found changes in brain activity—where different areas “light up”—that signal certain types of pain. Other doctors use scalp electrodes to measure pain through brain waves. Eventually, doctors hope to discover why some people recover from pain while others develop chronic pain.
“Your brain changes with pain,” explains David Thomas from the National Institutes of Health. “A zero-to-10 scale or a happy-face scale doesn’t capture anywhere near the totality of the pain experience.”
He will wipe away every tear from their eyes, . . . neither shall there be mourning, nor crying, nor pain anymore. — Revelation 21:4
(Clinical Research Assistant Kevin Jackson uses AlgometRx Platform Technology on Sarah Taylor’s eyes to measure her degree of pain at the Children’s National Medical Center in Washington. AP Photo/Manuel Balce Ceneta)
