Giuseppe Visconti, MD, PhD
Akitatsu Hayashi, MD
Joon Pio Hong, MD, PhD, MMM
Microsurgery has continuously evolved over the past 40 years. The early period was
dedicated to the delineation of soft tissue microvascular anatomy and understanding
the hemodynamic of flaps and their perfusion led to the establishment of fasciocutaneous,
musculocutaneous muscle and bony flaps.[1 ] In late 1980s, the anatomical work from Taylor and Palmer led to the introduction
of the angiosome concept and to the description of an average of 374 major perforators
through the human body.[2 ] Later, the clinical work by Koshima and Soeda opened the perforator era in microsurgery.[3 ]
After the introduction of perforator flap concept, the following 20 years were focused
on the discovery of new perforator flaps and large case series reports on the outcomes
of the most common perforator flaps for specific indications and reconstructions.
It progressively became clear and evident that perforator flaps represent the natural
evolution of conventional flaps, which lead to a paradigm shift in the reconstructive
algorithm: from the older “flap-of-choice” to the newer “flap choosen.”[4 ]
After the establishment of perforator flap concepts, it became also obvious that traditional
perforator flaps cannot always accommodate reconstruction needs especially when the
purpose is resurfacing rather than creating volume or filling space. In this perspective,
the thinning procedures already described for traditional flaps were then successfully
applied to perforator flaps,[5 ]
[6 ] although this generated different grade of confusions, especially in terminology.
Later, the advent of supermicrosurgery again pioneered by Koshima et al[7 ] further stimulated the next level of evolution: the ability to safely manipulate
vascular structures below 0.8mm means a further expansion in reconstructive freedom
and a reduction in surgery invasiveness. It is in fact possible, when indicated, to
harvest perforator flaps without dissecting the main pedicle and revascularize them
using recipient perforating vessels. Moreover, supermicrosurgery revolutionized also
the lymphatic surgery, with the introduction of supermicrosurgical lymphaticovenular
anastomosis that nowadays is an established method for treating lymphedema patients.
This fascinating evolution of microsurgery, however, still has a common denominator
limiting factor for all the procedure described: the exact knowledge of soft tissue
anatomy and microvascular anatomy of each patient varies from patient to patient.
This drawback has been already addressed in the past, initially by using the audible
Doppler examination and then introducing multidetector computed tomography scan[8 ] and magnetic resonance imaging[9 ] with the intent of locating reliable perforator and define the peculiar microanatomy
of each patient. However, those technologies still have shortcuts and were not enough
to enhance the confidence of microsurgeons, who still needed explorative dissection
to confirm the imaging findings as well as rely on skin coordinates system to locate
the hot perforator areas.
In the last decade, there was a fast evolution of portable imaging technologies that
can be directly used by the operating microsurgeon. First, plastic surgeons progressively
recognized the usefulness of ultrasound technology in perforator flap surgery that
allows a highly specific and highly sensible preoperative planning compared with any
other technology, especially when in the hands of the operating surgeon.[10 ] Moreover, the improved skills in high-frequency ultrasound and the introduction
of ultra-high frequency ultrasound allowed an enhanced visualization of very tiny
structures (such as terminal perforator branches within the subcutaneous tissue up
to and within the dermis as well as lymphatic channels) comparable to histologic images,
which further expand the preoperative preoperative vision, allowing high detailed
preoperative studies that lead to improve safety, efficacy, reliability, and microsurgical
creativity.[11 ]
[12 ]
[13 ]
[14 ]
[15 ]
[16 ]
[17 ]
[18 ]
[19 ]
[20 ] Ultrasound in experienced hands allows to skip the explorative time in perforator
flap dissection and move the process of study the “chosen flap” to that of ultrasound-choice
of the flap based on the most suitable microanatomy for the given indication. The
magic of mastering ultrasound is to perform a high-precision, more predictable, and
effective lymphatic supermicrosurgery procedure as well as increasing the confidence
related to perforator flap dissection leading to further creative solutions such as
thin, superthin and even pure-skin perforator flaps.[11 ]
[12 ]
[13 ]
[14 ]
[15 ]
[16 ]
[17 ]
[18 ]
[19 ]
[20 ]
We can say that ultrasound, either high-frequency and ultra-high-frequency, represents
nowadays the quintessence in microsurgery.
New imaging technologies are emerging with promising applications that may further
improve microsurgical outcomes and safety. The intraoperative microscope-integrated
laser tomography[21 ] allows to have more intraoperative details of lymphatic channel morphology and anastomosis
quality and photoacoustic technologies are emerging as a further low-invasive three-dimensional
technology for preoperative evaluation of microvascular and lymphatic anatomy.[22 ]
The advances in technologies must be strictly followed by plastic surgeons and microsurgeons
as the power of new imaging technology may further improve safety, efficacy, and cost-effectiveness
of microsurgery and may lead to new frontiers also eventually integrating such technologies
with the augmented reality[23 ] and the artificial intelligence of software.
We look forward to seeing microsurgical technology enthusiastic colleagues at the
next Imaging in Reconstructive Microsurgery Symposium on June 5, 2022 as Official
World Society of Reconstructive Microsurgery (WSRM) Postcongress meeting.
