NEW TECHNOLOGY OF TRANSCRANIAL ULTRASOUND …

NEW TECHNOLOGY OF TRANSCRANIAL

ULTRASOUND NAVIGATION FOR MINIMALLY

INVASIVE BRAIN NEUROSURGERY WITH REAL

TIME MONITORING OF MANIPULATOR

AFFECTING

Prof. Osipov Lev

PKF “IZOMED”, Moscow

2020 г.

MR T2 imaging of brain with tumor

Enlarged intraoperative ultrasound imaging

Intraoperative ultrasound imaging of tumor (green)after skull trepanation

Brain neurosurgery with MR or CT preoperative imaging for navigation often needs updated intraoperative ultrasound

Disadvantages of intraoperative ultrasound navigation

- large craniotomy hole for ultrasound probes;

- special positioning system with sensors on the

ultrasound probe for superposition MR and ultrasound

imaging;

- cerebrospinal fluid (CSF) drainage;

- artefacts of ultrasound imaging especially on the

saline/brain tissue barrier

- very high operator variability

Sastry R.et al. Applications of Ultrasound in the Resection of Brain Tumors. J Neuroimaging 2017 Jan; 27(1).

Transcranial ultrasound navigation (through scull bone) could

eliminate the disadvantages intraoperative ultrasound

navigation and keep its advantages:

- real time mode for exact navigation consideration brain shift, as a

result of craniotomy, gravity, tumor resection etc.;

- superior imaging quality and high rate of information renewal;

- Doppler mode for evaluation vessels state and blood flow

dynamic;

- information of acoustic tissue properties for differentiation.

Transcranial ultrasound navigation could provide minimally

invasive neurosurgery navigation and real time monitoring of

manipulator affecting.

However transcranial ultrasound imaging are of poor quality in

traditional ultrasound systems. This is because of the aberration

owing to cranial bone through which brain investigation is

performed.

The new technology of transcranial ultrasound imaging with

good image quality for navigation in brain neurosurgery was

developed in company PKF “IZOMED”, Moscow.

Project is focused on the significant improvement of quality and

information content of diagnostic ultrasound transcranial brain

imaging systems. The method implies the use of specific adjusting

procedure, which allows an evaluation and further compensation

of brain tissue-mediated distortion due to scull bone. Pilot

experiments have indicated a possibility of evaluation of such

distortion and verified method feasibility.

On the basis of the method effectiveness evaluation and pilot

experiments it may be concluded that the new method will be

extensively used in medical practice.

There was developed experimental system for estimation in vivo amplitude and

phase distortion of ultrasound signals in every element of phased array probe

after penetration scull bone (in this case os temporal)

It was important first step: if we can measure with good accuracy amplitude and

phase distortion of ultrasound signals consequently we could compensate these

distortions in beamformer of ultrasound system

Os temporal is the best “transparency window” in cranium owing to small

thickness and good position on scull for many ultrasound investigations

The scull with color separated os temporal Vertical section of os temporal taken by CT

Inner surface irregularity of os temporal is

the reason of signal distortions and

aberrations of ultrasound imaging

The sample of os temporal which was used for the next

experimens

For testing of innovation technology of obtaining better quality transcranial

ultrasound imaging there was developed the new experimental ultrasound

system for measurement and compensation distortion with adaptive

beamformer and phased array probe

The view of new experimental ultrasound system for measurement and compensation of distortion

Possibilities of new technology were estimating by comparison of images of

tissue equivalent ultrasound phantom through os temporal with traditional

transcranial scanning and with new technology application

Schematic illustration of tissue equivalent

ultrasound phantom with imitation of different

objects: points, vessels, tumors etc.

Imaging of ultrasound phantom

obtained by developed experimental

high class ultrasound system directly

(without scull bone and without

aberrations)

Images of ultrasound phantom without and with new

technology application as a result of scanning by phased array

probe through the sample of os temporal

Traditional technology image of

phantom through the sample of

os temporal (with aberrations)

New technology image of phantom

through the sample of os temporal

(with less aberrations)

Enlarged images of phantom through the sample of os

temporal for demonstration of high resolution of image

with new technology

Traditional technology New technology

In this experiment was used one dimensional phased array probe. With matrix (two

dimensional) probe the image quality with new technology would be much better!

Conclusion

• The expected result of the project realization: a new

technology that is expected to could provide minimally

invasive neurosurgery navigation and real time monitoring of

manipulator affecting will be widely implemented in medical

practice.

• The possibility and ways of commercialization of the

project. After the R&D is complete, the full-scale production

of ultrasonic diagnostic equipment of the new class with the

non-conventional diagnostic features will be started.

• Market prospects. The suggested method has no

equivalents, therefore the market of the ultrasonic navigation

systems based on the new technology will be perspective not

only for neurosurgery of brain but for other branches of

minimally invasive surgery.

Thank you for your attention!

Osipov Lev

Prof., Dr. of Science

General director PKF “IzoMed”

Tel: +7 (495) 611-21-09

E-mail: [email protected]