Researchers at UCL have developed a new hand-held scanner that can generate detailed 3D photoacoustic images in seconds, leading to potential earlier disease diagnosis in a clinical setting. Published in Nature Biomedical Engineering, the study shows that the scanner can provide real-time photoacoustic tomography imaging that visualizes changes in blood vessels up to 15mm deep in human tissues. Existing PAT technology has typically been too slow for clinical use, with scans taking over five minutes and requiring patients to be motionless. The new scanner accelerates image acquisition, making it suitable for clinical use for the first time.
The new speed of the scanner will improve image quality and make it more accessible to frail or ill patients. This technology could potentially diagnose cancer, cardiovascular disease, and arthritis in the near future, pending further testing. Professor Paul Beard, the corresponding author of the study, emphasized the significance of these technical advances in allowing clinicians to visualize aspects of human biology and disease that were previously inaccessible. Testing the scanner on patients with various conditions, the research team was able to produce detailed images that highlighted deformities and structural changes in the microvasculature.
Photoacoustic tomography (PAT) has been hailed as revolutionary since its early development in 2000, offering insights into biological processes and improving clinical assessment of major diseases. PAT utilizes laser-generated ultrasound waves to visualize tissues absorbing light and producing sound waves. PAT scanners fire short laser bursts at biological tissue, causing a slight increase in heat and pressure that generates an ultrasound wave containing tissue information. Detection of the ultrasound wave using light has been a key innovation in producing highly detailed images never seen before.
The new scanner has been tested in patients with various conditions such as type-2 diabetes, rheumatoid arthritis, and breast cancer, as well as healthy volunteers. In patients with diabetes, the scanner revealed deformities in the microvasculature of the feet, which could help in early diagnosis and understanding of disease progression. Similarly, cancer tumors with high densities of small blood vessels can be visualized using PAT imaging, assisting surgeons in better distinguishing tumor tissue from normal tissue during surgery.
By reducing the time needed to acquire images, the UCL researchers were able to solve the speed problem that had previously hindered the use of PAT in a clinical setting. Innovations in scanner design and image reconstruction mathematics allowed for faster image acquisition, with ultrasound waves detected at multiple points simultaneously, speeding up the process considerably. The scanner sensitivity to haemoglobin, a light-absorbing molecule that produces ultrasound waves, makes it particularly useful for various medical imaging applications. Future research will focus on confirming the clinical utility of the scanner with a larger group of patients.
Overall, the development of the new hand-held scanner at UCL represents a significant advancement in medical imaging technology. By providing highly detailed, real-time images of blood vessels and tissues, the scanner offers the potential for earlier disease diagnosis and better understanding of disease processes. With further research and testing, the scanner could become an essential tool in diagnosing conditions such as cancer, cardiovascular disease, and arthritis. The speed and quality of the images produced by the scanner make it suitable for clinical use, with the potential to transform medical imaging practices in the near future.
