Ultrasound Imaging Needle to Transform Heart Surgery

An unprecedented, high-resolution view of soft tissues.


Researchers at the UCL along with Queen Mary University of London (QMUL) have developed a new optical ultrasound imaging needle that can image heart tissue in real time.

The progressive innovation has been effectively utilized for insignificantly obtrusive heart surgery in pigs. It offers an exceptional, high-determination perspective of delicate tissues up to 2.5 cm before the instrument, inside the body.

In today’s date, doctors generally rely on external ultrasound probes combined with pre-operative imaging scans to track soft tissue and organs during keyhole procedures.

Dr. Malcolm Finlay, study co-lead and consultant cardiologist at QMUL said, “The optical ultrasound needle is perfect for procedures where there is a small tissue target that is hard to see during keyhole surgery using current methods and missing it could have disastrous consequences.”

“We now have real-time imaging that allows us to differentiate between tissues at a remarkable depth, helping to guide the highest risk moments of these procedures. This will reduce the chances of complications occurring during routine but skilled procedures such as ablation procedures in the heart. The technology has been designed to be completely compatible with MRI and other current methods, so it could also be used during brain or fetal surgery, or with guiding epidural needles.”

While developing this ultrasound imaging needle, scientists made sure that it was sensitive enough to image centimeter-scale depths of tissues when moving.

Study co-lead, Dr. Adrien Desjardins said, “This is the first demonstration of all-optical ultrasound imaging in a clinically realistic environment. Using inexpensive optical fibers, we have been able to achieve high-resolution imaging using needle tips under 1 mm. We now hope to replicate this success across a number of other clinical applications where minimally invasive surgical techniques are being used.”

Scientists used a miniature optical fiber and wrapped it with a customised clinical needle to deliver a brief pulse of light which generates ultrasonic pulses. Impressions of these ultrasonic heartbeats from tissue are identified by a sensor on a moment optical fiber, giving ongoing ultrasound imaging to control surgery.

Scientists also have developed highly sensitive optical fiber sensors based on polymer optical microresonators for detecting the ultrasound waves.

Study co-author, Dr. Richard Colchester said, “The whole process happens extremely quickly, giving an unprecedented real-time view of soft tissue. It provides doctors with a live image with a resolution of 64 microns, which is the equivalent of only nine red blood cells, and its fantastic sensitivity allows us to readily differentiate soft tissues.”

Scientists are now looking forward to making use of the technology for clinical trials.