DIAGNOSTIC SYSTEM FOR ULTRASOUND IMAGING OF BLOOD VESSELS THROUGH THICK BONES
OF SCULL "ULTRABRAIN"

New technology "ULTRABRAIN" developed by AMM - 2000, permits to avoid the influence of thick bones and provide imaging of brain blood vessels arbiitrary place of scull with high contrast and space resolution though thick bones of scull.

The existing methods of ultrasound imaging of cerebrum vessels are based on the utilisation of so called ultrasound windows ( temple, orbit, nape ) though which ultrasound scanning of the internal content of the scull is performed.

 DISADVANTAGES:

- The restriction of the area of imaging because of narrow ultrasound illuminating beam.
- The presence of the dead zones under Doppler investigation of cerebrum vessels.
- The small area of the ultrasound windows which does not permit to get sufficient information about vessels.
- The impossibility to receive the exactly images of vessels, their form, dimensions, placing an so on.
- The necessity of the additional education of the specialists and strong experience.

MAIN PHYSICAL PROBLEMS

•  Large absorption of HF signals in bones - 25Db/cm…40Db/cm;
•  Output useful reflected signal is too small for detection;
•  The maximum illumination intensity is limited by Standards;
•  Multiple reflections of ULS wave between external and internal bounds of scull;
•  The reflected signals and sidelobes are covering all time axis or range;
•  The impossibility to recognize the reflected useful signal.

MULTIPLE ULS REFLECTIONS SCULL BONES

EFFECTS OF MULTIPLE US REFLECTIONS

THE MATCHED WITH THE BONE PROCESSING

FUNCTIONAL SCHEME OF "ULTRABRAIN"

1 - ULTRASOUND SENSOR
2 - THE PHANTOM OF CRANIAL BONE OR THE FRAGMENT OF ORIGINAL CRANIAL BONE
3 - THE CASE
4 - NYLON SUTURE
5 - SILICON PIPES
6 - LIQUID MEDIUM WITH CEREBRAL TISSUE CARACTERISTICS

EXAMPLES OF ULTRASOUND IMAGES OF BLOOD VESSELS

THE PHANTOM WITH THICK BONES OF THE SKULL, FOR TUNING OF THE TEST-MODEL
OF THE SYSTEM "ULTRABRAIN

ULTRASOUND INVESTIGATION OF PATIENT

Upper Sagital sinus, transversal slice

Upper Sagital sinus, longitudinal slice

TRANSVERSAL SLICE THROUGH PARIETAL BONE

FUTURE WAYS OF THE SYSTEM DEVELOPMENT

• High-speed production of 3D ultrasound images of internal organs
• Ultrasound surgery through the thick cranial bones
• Hiperthermic ultrasound treatment of tumours with the purposeful transportation of medicins
• Ultrasound thermometry of internal organs (active and passive)

CONCLUSIONS

The new technology permits to generate ULS images of cerebrum vessels through thick bones of scull with high space resolution and contrast.
The ULS image can be received from arbitrary for the doctor of the position.

The technology is based on:

•  using complex signals with large base
•  evaluation of the profile of the internal surface of the scull bone in the place where the receiver and transmitter
   are fixed to obtain a correct image contrast
•  original software for preliminary signal processing and secondary image processing;

The results obtained by the research team let us to conclude that the new developed method can produce on - line ULS images of cerebral vessels which have the compatible quality with angeography images.