D.V. Koshelenko, S.A. Letun
Head of Clinic Tech Inc. (USA)
Moscow Office
The development of a new generation of non-linear computer scanner (metatrons) which
make use of multidimensional virtual imaging of the body area of interest, has facilitated
substantially improved efficiency of the NLS-method and even expanded its fields of
application (despite the MRT competition). The originally volumetric pattern of
scanning is a distinctive feature of the multidimensional NLS imaging. The data thus
acquired are an integral array, which facilitates reconstructing multidimensional virtual
images of anatomical structures. In this connection the virtual NLS is widely used
especially for angiographic investigations with a three-dimensional reconstruction of
vascular formations.
Another promising field of application of the three-dimensional image reconstruction,
based on the data acquired by means of multidimensional NLS, is the study of hollow
organs with a “virtual NLS-scopy” involved. This kind of a system was developed by
Medintech Company for their high-rate multidimensional Z-series non-linear scanners,
and was called Hunter. The high resolution maintained during spiral scanning and the use
of LAPP system (a system of parallel processors with a powerful computational
capability and speed of operation) enables the implementation of the principal of “virtual
NLS-scopy” on a Voxel Z multimodal DICOM-compatible work station, which is the
basic system for imaging and subsequent data processing with Medintech scanners.
NLS images are made ready for visual analysis by means of the 4D Tissue, an original
company-developed method, that enables not only virtual multidimensional images of
anatomical structures but also selection of a particular biological tissue of interest to give
it an extra dimension, and additionally visualize bones, soft tissues and vessels.
A specific feature of representing virtual data by the Hunter system is its simultaneous
visualization of surfaces of cavatus and extramural formations located outside the lumen
of the cavity under examination (e.g. lymph nodes, vessels). The acquired images form a
natural sequence of virtual NLS shots, while a special navigation program automatically
determines the path of the “virtual scanner” by center of the cavity under examination.
The path of the motion can be chosen by operator using some other settings, which allow
detailed NLS pictures by changing the view fields. A raised representation of the cavity
surface is also achievable by shaping particular artificially shaded areas. The presulting
sequences of NLS shots can be easily converted into a standard VHS video format by
means of the epi-Client program and can be used in standard video systems, in particular
for teleradiology.
The Hunter system is primarily designed for case detection of obstructive processes in the
upper respiratory passages, bulky esophageal, gastric or colonic formations,
atherosclerotic lesions of large vessels, and disorders affecting paranasal sinuses, urinary
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bladder or spinal canal. The data gathered by “virtual NLS-scopy” facilitates selection of
the optimum spot for biopsy and can define the extent of surgical intervention in good
time.
This technique can be used both stand alone and as a useful linking element between
tomographic, endoscopic and NLS investigations.
The Medintech’s latest development is its Pincers stereo tactic manipulator integrated
into a computer scanner, which is a convenient tool for planning interventional
procedures monitored by NLS. The Pincers comprises a controlled stereo tactic
manipulator (“arm”), a flat gentry-mounted monitor, a cable system and software. The
system provides the physician with the means of simulating and performing
interventional procedures through an interactive link between the virtual NLS and the real
operational field.