A new optical ultrasound needle developed by researchers at UCL and Queen Mary University of London (QMUL) is allowing soft tissues inside the patient to be imaged in real-time. The team has been developing this technology in a clinical setting for over four years.

Minimally invasive surgery, or keyhole surgery, is a surgical technique that operates on the target location using a small incision located elsewhere in the body. Currently, doctors are relying on external ultrasound probes and pre-operative imaging scans to visualize the soft tissues. This has limits on resolution, location, and differentiation of soft tissues. This new ultrasound imaging needle provides a high resolution image of 64 microns (equal to 9 red blood cells), up to 2.5cm in front of the instrument, inside the patient’s body. This allows a detailed differentiation and real-time view of the soft tissues, without harm to the patient.

The optical ultrasound needle functions using miniature optical fibres that delivers a brief pulse of light. This light generates ultrasonic pulses that are reflected by tissues. The reflections are detected by a sensor on the second optical fibre, resulting in the real-time images. This new optical ultrasound needle can be used on needle tips under 1mm. It is good for small tissue targets and has potential application in guiding epidural needles.