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]