To understand what’s going on with a patient, doctors may take a biopsy—a sample of tissue extracted from a suspicious lump, for example. Fine needles are typically used for this purpose, in a technique that has remained mostly the same over the last 150 years.
“Biopsy yields – the amount of tissue extracted – are often inadequate, with some studies showing that up to a third of fine-needle biopsies struggle to get enough tissue for a reliable diagnosis,” said Heikki Nieminen, an inventor of a new vibrating biopsy needle that overcomes these challenges.
“A biopsy can be painful, and the wait for the results from a diagnostic test can be a highly distressing time for the patient and family, especially if diagnosis needs re-biopsies to be conclusive. We wanted to make the procedure more gentle for the patient, and increase the certainty that the test will be able to give us an answer on the first attempt,” explained Nieminen.
Nieminen and researchers at Aalto University in Finland have built a device called the SonoLancet that uses conventional syringes and fine needle tips. It works by vibrating the needle tip at incredibly high frequencies—around 30,000 times per second—which causes the tissue around the needle tip to behave more like a liquid than a solid. This enables the user to extract more of the tissue through the narrow needle tip while minimizing discomfort to the patient.
“The vibrations are localized to just the tip, so it doesn’t affect any other tissue except a small region around the needle,” said Emanuele Perra, another scientist involved in the work. “We were able to show that the ultrasonic vibrations increase the biopsy yield by 3 to 6 times compared to the same needle without ultrasound, which was even greater than we hoped for.”