- Australian scientists created the world's smallest imaging device capable of taking pictures inside arteries
- They used 3D microprinting to overcome manufacturing obstacles of miniature image probes
- The device is also useful in probing small animals' organs and arteries
Endoscopes have long been used to have a closer, real-time look at what's happening inside organs.
Vital for clinical diagnosis and treatments, it's important that these imaging devices are the right size in order to avoid causing any damage or tears in the delicate organs.
But you could only go so small without losing imaging quality – until now.
Australian scientists have created the world's smallest imaging device that's able to map the arteries of humans and even mice.
They developed a novel ultrathin probe fabrication technique that uses 3D microprinting to create micro-optics smaller than 130 micrometres in diameter. The whole imaging probe is about 0.457 mm in diameter, including the catheter sheath where the imaging probe can rotate freely while protecting tissue.
"The ability to provide microstructural information with the smallest optical coherence tomography catheter opens a gateway for novel minimally invasive applications in disease," say the scientists.
Improved image quality
While there have been previous miniaturised probes, the quality of their imaging has been extremely low due to the physical aperture size and issues relating to depth of focus and resolution.
These are related to the difficulty of creating such small lenses without distorting the imaging.
Their device overcomes these limitations by using two-photon polymerisation to 3D print 125-micrometre-diameter micro-optics directly onto the optical fibre.
"The utility of the ultrathin endoscope is demonstrated on both in situ preclinical (mouse) and ex vivo clinical (human) models of cardiovascular disease.
"We are now able to reveal details of the tissue microarchitecture at depths not previously achieved with such small imaging probes."
The human in the trial was a 75-year-old man undergoing artery surgery to reduce the risk of stroke after suffering an attack six months earlier.
With the tiny probe, they were able to identify high-risk plaques that may cause heart attacks and strokes.
"The reliability and versatility of our technique leads to a plethora of functionalities that are not feasible with conventional probe fabrication methods."
"One such example, as demonstrated in this work, is to enable the correction of spherical aberration and astigmatism, which ensures high-resolution imaging over a long depth of focus."
This probe can also be incredibly useful with small and difficult-to-reach organs, making it safer for patients and enhancing their treatments. It can also guide biopsies and image the inside of the ear's cochlea among other applications.
Image credit: Adelaide University