New Laser-based system achieves noncontact medical ultrasound imaging

Amazing stuff! Good news! This could be a breakthrough and major improvement of medical diagnostics! I did not know that conventional ultrasound diagnostics had such serious limitations.

"... a new medical imaging device: the Noncontact Laser Ultrasound (NCLUS). This laser-based ultrasound system provides images of interior body features such as organs, fat, muscle, tendons, and blood vessels. The system also measures bone strength and may have the potential to track disease stages over time. ...

Limitations of ultrasound

... Freehand manipulation of the probe by sonographers to obtain the best viewing window into the body interior leads to imaging errors. More specifically, as sonographers apply pressure to the probe by feel, they randomly compress the local tissue where the probe makes contact, causing unpredictable changes in the tissue properties that impact the travel paths of the ultrasound waves. This compression distorts tissue-feature images with some unpredictability, meaning feature shapes are not accurately plotted. In addition, tilting the probe, even slightly, changes the angle plane of the image view — skewing the image and creating uncertainty of where features are positioned in the body.

The image distortion and positional reference uncertainty are significant enough that ultrasound cannot resolve with sufficient confidence, for example, whether a tumor is getting larger or smaller and precisely where the tumor is located in the host tissue. Furthermore, the uncertainty in feature size, shape, and position will vary upon repeat measurement, even for the same sonographer trying to retrace their steps. This uncertainty, termed operator variability, is more severe when different sonographers attempt the same measurement, leading to inter-operator variability. Because of these drawbacks, ultrasound is often restricted from tracking cancerous tumors and other disease states. Instead, methods such as magnetic resonance imaging (MRI) and computerized tomography (CT) are mandated to track how diseases progress — even with their vastly higher cost, greater system size and complexity, and imposed radiation risk. ...

By fully automating the process for acquiring ultrasound images, NCLUS has the potential to reduce the need for a sonographer and to mitigate operator variability. The laser positioning can be accurately reproduced, thus eliminating variability across repeated measurements. Because the measurement is noncontact, no localized tissue compaction or its related distortion to image features occur. Moreover, similar to MRI and CT, NCLUS provides a fixed-reference-frame capability using skin markers to reproduce and compare repeat scans over time. To support such tracking capabilities, the laboratory team developed software that processes ultrasound images and detects any changes between them. Requiring neither manual pressure nor coupling gels (as required by contact probes), NCLUS is also ideal for patients with painful or sensitive body areas, in fragile states, or at risk of infection. ..."

Laser-based system achieves noncontact medical ultrasound imaging | MIT News | Massachusetts Institute of Technology Noncontact Laser Ultrasound offers capabilities comparable to those of MRI and CT but at vastly lower cost, in an automated and portable platform.

The Noncontact Laser Ultrasound portable, multiple-degree-of-freedom plane-positioning armature stages an optical head, which houses a miniaturized laser source and receiver, flexible optical fibers, mirrors, and a camera.