Over the years, diagnostic imaging has gone through
a number of technological innovations. From this point of view the liveliest
sector has undoubtedly been that of ultrasounds: the appearance of high-performance
microprocessors and especially the introduction of digital beam formers led
to the digital reconstruction of images while preserving all information contained
within tissues and markedly improving the spatial, contrast and details resolution
in a way that was not possible before.
The signal transmission process also made a major step forward thanks to the
new probes which with their new piezoelectric materials have improved electromechanical
couppling coeficients; we now have multi-layer probes, matrix probes and probes
with special focusing lenses. Moreover the advent of new image reception processes
has made it possible to recontruct images using not only fundamental echoes
but also harmonic echoes coming form tissues or from the micro-bubbles contained
in the contrast medium injected in the blood stream.
Different systems have been put onto the market that enable reading harmonic
imaging both through a static and a dynamic representation and the use of
Doppler signal combined to the grey scale. As for image recontruction, there
is now the possibility to obtain the equalization of the ultrasound response
spanning the whole imaging field and to have representations captured from
different observation or acquisition points with an extension of the field
of view and 3D/4D reconstruction.
Computerized Tomography has made a major step forward with the introduction
of new spiral and/or multi-slice CT units. This resulted in a reduction of
scanning time and the possibility to obtain high-definition studies of organs
in motion, like the heart, and of difficult patients like those with multiple
traumas and the elderly.
Magnetic Resonance Imaging has extended its field of application to include
new organs and diseases; all of which was possible thanks to the introduction
of new fast sequences, the use of organ-specific contrast media, the availlability
of open systems and the development of new coils that provide a better rendering
of gradients.
The new machines have brought about new MR-guided surgical and interventional
procedures.
The advent of Digital Imaging also means that images of ultasounds and other
imaging-based techniques can now be stored and transfered using PACS (Picture
Archiving and Comunication Systems) systems.
The DICOM standard has made imaging processing easier. For ultasounds, information
transfer requires the compression of scanning frames; to this purpose the
JPEG, MJPEG, MPEG and Wavelet formats are the ones that allow the operator
to preserve dynamic information.
This section of the website will report impressions and opinions of medical
users about the advantages offered by recent technogical advances.