Ultrasonic brain imaging through the skull
An interruption to the blood supply to the brain even partially may cause a rapidly developing loss of brain function. Stroke is treated as a medical emergency and may lead to a permanent neurological damage or even death unless it is early diagnosed and treated. Due to its size and complexity, stroke incidents have increased over the past years. Nowadays, it is considered to be the third leading cause of death and the main cause of disabilities in the Western world. Urged by this the UMEDS project aimed at reducing the impact of stroke through early diagnosis, prompt therapy and reliable monitoring. With the aid of new non-invasive technologies the project focused on improving the quality of life of patients affected by stroke. By exploiting latest developments in micro-bubble technology and ultrasonographic harmonic imaging new ultrasound techniques and technologies were realised. As such, an ultrasonic device for brain scanning was also produced. On the basis of time reversal mirrors, the new, fully programmable prototype developed allows compensation of distortion due to inhomogeneous media. The innovative ultrasonic scanner uses a novel aberration correction algorithm for high resolution imaging of the brain. The innovative feature of the new ultrasound brain scanner is that it provides a very good correction of the defocusing effect of the skull during the calibration process. At the end of the calibration process that lasts only one minute, the set of emission signals is stored in the electronics offering real time images. The device was used to gather high resolution in vitro images transcranially. The promising results showed that the prototype could completely restore the resolution and enhance the contrast as compared to classical imaging. The capabilities of this breakthrough technology will be further explored also in the case of real time in vivo brain imaging.
