10.14639/0392-100X-N0757
Objective. The recent introduction of 3D exoscopic surgery has allowed interesting technical improvements in head and neck surgery resulting in technical solutions that are also applicable to neck dissection. The aim is to replace robotic surgery while minimising the costs of the procedure.
Methods. Based on these considerations, we conducted a preclinical investigation in the cadaver lab focused on approaching conventional neck dissection using a retroauricular incision, and evalute the applications and usefulness of the Storz 3D Exoscopic System at different stages of the surgical procedure. The acronym RAND-3D (3D exoscopic surgery) was coined to describe the application of this optical tool in neck dissection.
Results. The current study in the cadaver lab indicates that RAND-3D is an acceptable alternative operating technique in performing neck dissection by a retroauricular approach. Technically feasible and safe, this technique assures a complete compartment-oriented dissection without damaging major vascular or nervous structures. Conclusions. This approach can be used in selected cases with a clear cosmetic benefit and represents a valid alternative to endoscopic- and robotic-assisted neck dissection.
application/xml
1827-675X
757
5
en
Giovanni Succo
https://creativecommons.org/licenses/by-nc-nd/4.0
ACTA Otorhinolaryngologica Italica
3D surgery
VITOM-3D assisted neck dissection via a retroauricular approach (RAND-3D): a preclinical investigation in a cadaver lab
Text.Serial.Journal
https://www.actaitalica.it/
40
Head and neck
2020-12-03
2020-03-22
2020-12-04
2020-12-04
343-351
1
Giovanni Succo
2020/12/03
10.14639/0392-100X-N0757
343
Head and Neck Oncology Unit, Candiolo Cancer Institute, FPO - IRCCS, Candiolo (TO), Italy; Department of Oncology, University of Turin, Orbassano (TO), Italy
1827-675X
5
3D surgery
351
VITOM-3D assisted neck dissection via a retroauricular approach (RAND-3D): a preclinical investigation in a cadaver lab
https://www.actaitalica.it/article/download/757/462
40
ACTA OTORHINOLARYNGOLOGICA ITALICA 2020;40:343-351; doi: 10.14639/0392-100X-N0757




Head and neck


VITOM-3D assisted neck dissection via a
retroauricular approach (RAND-3D): a preclinical
investigation in a cadaver lab
Dissezione laterocervicale mediante approccio retroauricolare assistito da sistema
VITOM-3D (RAND-3D): studio preclinico in cadaver lab
Erika Crosetti1, Giulia Arrigoni1, Andrea Manca1, Marco Fantini1, Alessandra Caracciolo1, Francesco Sardanapoli1,
Giovanni Succo1,2
1
  Head and Neck Oncology Unit, Candiolo Cancer Institute, FPO - IRCCS, Candiolo (TO), Italy; 2 Department of Oncology, University
of Turin, Orbassano (TO), Italy


SUMMARY
Objective. The recent introduction of 3D exoscopic surgery has allowed interesting techni-
cal improvements in head and neck surgery resulting in technical solutions that are also
applicable to neck dissection. The aim is to replace robotic surgery while minimising the
costs of the procedure.
Methods. Based on these considerations, we conducted a preclinical investigation in the           Received: March 22, 2020
cadaver lab focused on approaching conventional neck dissection using a retroauricular            Accepted: August 6, 2020
incision, and evalute the applications and usefulness of the Storz 3D Exoscopic System at
different stages of the surgical procedure. The acronym RAND-3D (3D exoscopic surgery)            Correspondence
was coined to describe the application of this optical tool in neck dissection.                   Erika Crosetti
Results. The current study in the cadaver lab indicates that RAND-3D is an acceptable             Head and Neck Oncology Unit, FPO IRCCS, Can-
alternative operating technique in performing neck dissection by a retroauricular approach.       diolo Cancer Institute, 10060 Candiolo (Turin) Italy
Technically feasible and safe, this technique assures a complete compartment-oriented dis-        Tel. + 39 011 9933663
section without damaging major vascular or nervous structures.                                    E-mail: erika.crosetti@ircc.it
Conclusions. This approach can be used in selected cases with a clear cosmetic benefit and
represents a valid alternative to endoscopic- and robotic-assisted neck dissection.               Funding
                                                                                                  This research was funded by: Regione Piemonte
KEY WORDS: 3D, exoscope, neck dissection, 3D surgery                                              AD FUNCTIONEM (years 2015–2018); FPRC
                                                                                                  5xmille 2016 Ministero della Salute Progetto
                                                                                                  ARDITE; Fondi Ricerca Corrente 2020, Ministero
RIASSUNTO                                                                                         della Salute.
Obiettivo. Il recente avvento della chirurgia esoscopica 3D ha consentito, nell’ambito
della chirurgia cervico-cefalica, l’introduzione di interessanti innovazioni tecnologiche,
                                                                                                  Conflict of interest
risultanti in soluzioni tecniche applicabili anche alla chirurgia del collo, con l’obiettivo di   The Authors declare no conflict of interest.
rappresentare un’alternativa alla chirurgia robotica, minimizzando i costi della procedura.
Metodi. Sulla base di queste considerazioni abbiamo recentemente condotto uno studio
pre-clinico nel nostro cadaver lab, focalizzato sull’esecuzione dello svuotamento linfono-          How to cite this article: Crosetti E, Arrigoni G,
dale laterocervicale con approccio retroauricolare, valutando le applicazioni e l’utilità del       Manca A, et al. VITOM-3D assisted neck dis-
Sistema Esoscopico 3D Storz nei vari steps dell’intervento. Abbiamo coniato l’acronimo di           section via a retroauricular approach (RAND-
                                                                                                    3D): a preclinical investigation in a cadaver lab.
RAND-3D (chirurgia esoscopica 3D) per descrivere l’impiego di questo tool ottico nell’e-
                                                                                                    Acta Otorhinolaryngol Ital 2020;40:343-351.
secuzione di tale procedura chirurgica.                                                             https://doi.org/10.14639/0392-100X-N0757
Risultati. Il seguente studio condotto nel cadaver lab ha indicato che la tecnica RAND-3D
rappresenta una valida alternativa per l’esecuzione dello svuotamento del collo con ap-           © Società Italiana di Otorinolaringoiatria
proccio retroauricolare. Questa metodica, tecnicamente fattibile e sicura, permette una dis-      e Chirurgia Cervico-Facciale
sezione compartimentale, senza danno alle principali strutture vascolo-nervose cervicali.
Conclusioni. Questo approccio può essere impiegato in casi selezionati con un chiaro                             OPEN ACCESS
finalismo estetico, rappresentando una valida alternativa alle metodiche endoscopiche e
                                                                                                  This is an open access article distributed in accordance with
robotiche.                                                                                        the CC-BY-NC-ND (Creative Commons Attribution-Non-
                                                                                                  Commercial-NoDerivatives 4.0 International) license. The
PAROLE CHIAVE: 3D, esoscopio, svuotamento laterocervicale, chirurgia 3D                           article can be used by giving appropriate credit and mentio-
                                                                                                  ning the license, but only for non-commercial purposes and
                                                                                                  only in the original version. For further information: https://
                                                                                                  creativecommons.org/licenses/by-nc-nd/4.0/deed.en




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Introduction                                                    enhanced using 3D exoscopic technology in more remote
Traditionally, surgery for head and neck malignancies in-       areas.
volves open neck approaches aimed at radical removal of         The primary end point was to demonstrate the effectiveness
the primary tumour together with cervical lymph nodes, al-      of this technology in retroauricular or facelift approaches
lowing the surgeon to obtain good control of the disease;       to neck dissection. The secondary end point was to assess
however, occasionally, negative post-operative aesthetic        which node levels could be dissected using the 3D exo-
and functional sequelae result.                                 scopic system, the docking and setting of the procedure,
The need to implement surgical approaches that minimise         and the advantages and limitations of the technique. The
the morbidity and impact of treatments has given great im-      tertiary end point was to become familiar with a traditional
petus to the development of minimally invasive techniques,      technique carried out using a remote approach, to be con-
such as laser surgery and robotic surgery 1,2.                  sidered as a rescue procedure in the case of major bleeding
As far as treatment of the neck is concerned, to date, not      complications during a robotic neck dissection.
much has changed in terms of surgical technique, since the
cervical open neck approach remains the conventional one,       Materials and methods
even in the case of transoral surgery on the primary tumour,
and also resulting in the paradox of minimally invasive sur-    Four human cadavers were obtained from the Italian Acad-
gery on T and conventional surgery on N, and weakening          emy of Anatomical Dissection (AIAD). Three cadavers
the concept of minimal invasiveness. This has prompted          were male and one was female. Dissection was carried out
surgeons to try to develop minimally invasive neck dissec-      bilaterally on each cadaver by two senior head and neck
tion techniques using endoscopic and robotic approaches.        surgeons.
Endoscopic-assisted and robot-assisted neck dissection
present limitations and disadvantages. Of these, the main       Technology
the duration of surgery, longer than the standard approach,     The video telescope operating microscope (VITOM®; Karl
the need for surgeons to develop skills in endoscopic and       Storz, Tuttlingen, Germany) system is an exoscope with
robotic techniques and the overall higher costs of the pro-     0° or 90° camera options. VITOM-3D has zoom and fo-
cedures (about six times higher in the Korean experience        cus functions, integrated illumination and horizontal align-
using robotic neck dissection) 3-7.                             ment. The camera offers a magnification of 1–2× depend-
The recent introduction of 3D exoscopic surgery has al-         ing on the working distance and the size and resolution of
lowed interesting technical improvements in head and neck       the monitor used. The surgical field is visualised by a cam-
surgery resulting in technical solutions that are also appli-   era system which supports an output signal of 1920×1080 p
cable to neck dissection, with the aim of replacing robotic     and with a 16:9 image format; progressive scanning deliv-
surgery but minimising the costs of the procedure 8.            ers crystal-clear images with smooth motion, even if there
Specifically, exoscopic surgery is based on the use of a        is rapid movement. The 3-chip sensor technology in the
sterile 3D optical device, called an exoscope, placed in the    camera head ensures natural colour rendition.
surgical field and oriented with different inclinations but     The exoscope is positioned on a versatile self-supporting
technically about 40 cm distant from it. The exoscope also      arm, specially developed for use with the VITOM® system,
illuminates the surgical field in depth, since it is equipped   which allows a simple and precise positioning of the system.
with two light cables with Xenon sources, and produces 4K       The arm is mounted on a mobile trolley and can be trans-
images on a 55″ screen positioned about 3-4 metres from         ported and positioned quickly in the operating room. Thanks
the surgeon. In some steps in the surgical procedure, the       to its pneumatic cushioning, the arm allows weight compen-
exoscope replaces the surgeon’s eyes thereby improving          sation for the VITOM® system. The braking effect of each
magnification. This allows the possibility to carry out the     individual joint can be set individually. Furthermore, the arm
neck dissection through a retroauricular incision, combin-      is noted for its easy handling: the VITOM® system can be
ing direct and 3D exoscopic vision and resulting in operat-     easily positioned with one hand. Different directions of view
ing times no longer than 20% of previous times and with a       are possible depending on the surgical site being treated.
comparable level of feasibility, determined by the perfect      HD imaging also provides a sense of depth to improve
visualisation of the surgical field even in the more remote     anatomical orientation. The camera is connected to a 3D
cervical areas (levels Ib–IV).                                  monitor and 3D passive-polarised glasses, with an anti-
The goal of this study is to analyse the technical details      fog coating, or 3D clip-on glasses, circularly polarised, are
of neck dissection in a cadaver lab carried out using a re-     worn to view the monitor. An intuitive control unit with 3D
mote approach in what is virtually conventional surgery but     wheel (joystick) with four programmable function keys is



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used to control the camera. The joystick can be used with                    A modified retroauricular or facelift skin incision is per-
the sterile coating by the surgical assistants, or without the               formed without pre-auricular extension (Fig. 2). The modi-
coating by other members of the surgical team not directly                   fied facelift incision, given its extension into the pre-au-
working on the operating field. The joystick can also be                     ricular region, allows for more straightforward and faster
used to control an instrument holding system. To increase                    dissection, providing a wider ‘working space’, especially
the illumination of the operating field, it is possible to place             for patients who need a dissection of level Ib. The median
an annular illuminator device on the head of the exoscope,                   operating time for cutaneous flap harvesting and placement
connected to a second Xenon light source.                                    of skin retractor was 38 minutes (range 25-78 minutes).
In order to carry out a hybrid procedure in which a large                    The median operating time for 3D exoscopic-assisted neck
part of the operation is performed under direct control and                  dissection (levels Ib–V) was 83.2 minutes (range 73-103
only the dissection of the most distant layers from the inci-                minutes).
sion (levels IV and Ib) is performed under exoscopic 3D                      Neck dissection was successfully performed from levels I
vision, the polarising lenses were adapted to the 3.5× mag-                  to V in all four cadavers. The skin flap is elevated under di-
nification operating loupes.                                                 rect vision along a subplatysmal plane, and the inferior as-
                                                                             pect of the parotid gland, the great auricular nerve, and the
Operating lab setting                                                        external jugular vein is identified which could be ligated
The first and second surgeons are seated on the same side                    and sectioned as well as spared. The latter two anatomical
as the neck dissection. The 55” monitor is positioned con-                   structures represent the anatomical landmarks used to iden-
tralaterally in front of them, at a distance of about 2.5 me-                tify the correct subplatysmal plane.
tres. The assistant is placed at the head of the cadaver. The                The anterolateral margin of the sternocleidomastoid mus-
endoscopic cart is positioned at the bottom of the operating                 cle and the angle of the mandible are then identified. The
bed with a second 3D monitor for the assistant. The first                    angle of the mandible, an important landmark for the man-
and second surgeons also wear operating loupes over polar-                   dibular branch of the VIIth cranial nerve, is then marked
ising clip-on lenses to view the monitor when necessary. At                  using a sterile pencil, over the fat tissue so as to always
present, the exoscope is mounted on a mechanical holder,                     maintain these anatomical structures in the field of view.
positioned behind the two surgeons and oriented towards                      The dissection proceeds with the aid of the 3D exoscope.
the level to be dissected and is moved by an assistant. The                  We identified inferiorly the upper margin of the clavicle,
latter controls the exoscope joystick. All team members                      medially the anterior belly of the contralateral digastric
wear 3D glasses. Throughout the operation, the exoscope                      muscle, and laterally the anteromedial margin of the trape-
is positioned behind the first two operators and directed to-
wards the level to be dissected (Fig. 1).

Results
The cadaver is placed in the supine passive position with
neck slightly extended and turned contralateral to the side
that will be operated. It is useful to identify and mark the
external jugular vein on the skin, if present, and the mar-
gins of the platysma/sternocleidomastoid muscle.




A                                      B

Figure 1. A) Schematic of operating lab setting. B) Operating lab setting.   Figure 2. Modified retroauricular or facelift skin incision (red line).



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E. Crosetti et al.




                                                                                Figure 4. Surgical view (left side) after level IIa dissection (ECA: external ca-
                                                                                rotid artery; SAN: spinal accessory nerve; SCM: sternocleidomastoid muscle).


                                                                                mostatic manoeuvers, carried out by the second surgeon
                                                                                around the hypoglossal nerve and thyrolinguofacial trunk,
Figure 3. Surgical view (left side) after self-retaining retractor placement.
                                                                                can benefit from exoscopic vision (Fig. 4). The neck dis-
                                                                                section then proceeds with dissection of level IIb. The di-
                                                                                gastric muscle is retracted upwards by the third assistant
zius muscle. A self-retaining Koh’s retractor or Mikulitz’s                     using an Army-Navy retractor and the spinal accessory
spatula is then placed and kept raised by the third assistant                   nerve (SAN) is dissected (Fig. 5). Level IIb is completely
(Fig. 3). In this step, the first and second surgeons work                      dissected under direct vision.
next to each other. To better harvest the subplatysmal flap                     The percentage of surgery carried out under direct vision
up to the clavicle inferiorly, it is preferable that the first                  vs 3D exoscopic vision was calculated (90% vs 10%).
surgeon is positioned at the head of the cadaver or that this                   VITOM-3D was useful to the assistant to aid precision in
step is carried out by the second surgeon.                                      haemostatic manoeuvers.
Different levels in the neck (I, IIa, IIb, III, IV, Va, Vb) are
                                                                                Dissection of level III
then dissected as required using the traditional surgical
                                                                                For dissection of level III, the operation always proceeds in
technique, with vascular clips and haemostatic cutting/
                                                                                a medial  lateral direction. Dissection from the deep plane
coagulation devices such as bipolar scissors and LigaSure
                                                                                and the medial-lateral shifting of the loose and fascial cellular
Maryland forceps. Surgical instruments (forceps, scissors)
                                                                                tissue isolated so far allow the SAN and the cervical plexus to
must be a minimum length of 24 cm so as to be able to
                                                                                be identified. The specimen is then gently pulled downwards,
work in deep spaces without any difficulty.                                     and the perivasal fasciae cut with scissors (Fig. 6).
The aid provided by the 3D vision consists of useful light-
ing of more distant areas of the neck and improving the
visualisation of anatomic structures. The visualisation is
exactly the same for both surgeons providing great preci-
sion in the surgical manoeuvers.
At the end of the procedure, we decided not to send the
specimen to the pathologist because the main aim of our
preclinical investigation was evaluation of the feasibility of
the approach.

Dissection of level II
To dissect this level, the first surgeon is positioned on the
same side as the neck dissection while the second surgeon
stands next to the first surgeon towards the patient’s head.
                                                                                Figure 5. Surgical view (right side): the digastric muscle is retracted upwards
The dissection proceeds in a medial  lateral direction                         by the third assistant using an Army-Navy retractor and the spinal accessory
quickly carried out under direct vision and only some hae-                      nerve (SAN) is dissected.



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                                                                                       When dissecting the lower part of level IV, to prevent any
                                                                                       possible lymphorrhage due to damage to the thoracic duct/
                                                                                       great lymphatic vein, it is mandatory to place multiple vas-
                                                                                       cular clips before cutting the fat tissue. The side of dissec-
                                                                                       tion did not have any significant effect on the performance
                                                                                       of neck dissection.
                                                                                       This is undoubtedly the most challenging step in the opera-
                                                                                       tion because, at level IV, the working space is extremely
                                                                                       narrow and the risk of an inadvertent injury to the internal
                                                                                       jugular vein (IJV) or thoracic duct is high. Also in this step,
                                                                                       the exoscope is useful for sharing the same good vision
                                                                                       among all surgeons; however, the long working distance
Figure 6. Surgical view (right side): for the dissection of level III, the operation
always proceeds in a medial  lateral direction, from the deep plane and the
                                                                                       makes this dissection lengthy and difficult to manage, even
medial-lateral shifting to allow the SAN and the cervical plexus to be identified.     for expert surgeons.
(IJV: internal jugular vein; SAN: spinal accessory nerve).                             To facilitate dissection of level IV, and to dramatically re-
                                                                                       duce the risks of vascular/lymphatic injury, it is extremely
                                                                                       useful to make a small incision (5 cm) midway between
The positions of the surgeons and the exoscope are the                                 the cricoid cartilage and sternal notch, as is currently per-
same as in level II dissection. To dissect this level, the per-                        formed in thyroid surgery. The breadth of this incision
centage of 3D exoscopic vision rose to 20%, in particular                              should exceed the external border of the sternocleidomas-
when dissecting the lower part of this level, meaning that                             toid muscle by 1 cm. The concept is to create a service skin
even the first surgeon can improve his accuracy.                                       window, allowing the lateral margin of the sternocleido-
                                                                                       mastoid muscle, the upper belly of the omohyoid muscle,
Dissection of levels IV–V                                                              and the cervical vascular-nervous axis to be identified and
For the dissection of levels IV and V, the first surgeon                               then dissecting this level upward, reaching level III (Fig. 8).
moves to the head of the cadaver. Another possibility is                               Highlighting the phrenic nerve and the brachial plexus, dis-
that the second surgeon proceeds with cervical dissection                              section of the inferior part of levels IV and V is completed,
in this step. The dissection of level V is then carried out in                         certainly the most delicate and difficult to manage step
a lateral  medial direction under direct vision in conven-                            coming from a remote behind-the-ear approach.
tional mode without any particular difficulties. To dissect                            This surgical solution is also useful when performing thy-
level IV, the retractor blade raising the skin flap is posi-                           roid surgery for malignancies, where neck dissection is also
tioned towards the sternal notch. An assistant retracts the                            required due to cervical metastases, allowing an effective
sternocleidomastoid muscle apart using a Richardson’s re-                              surgical procedure and leaving only a small visible scar.
tractor. The surgical instruments are directed caudally and                            To dissect these levels, the rate of 3D exoscopic vision is
the exoscope is directed towards the clavicle and sternal                              about 20% when proceeding only via a retroauricular ap-
notch (Fig. 7).                                                                        proach; while it is less than 5% when proceeding via the




Figure 7. Surgical view (right side): dissection of level IV (the omohyoid mus-        Figure 8. Modified retroauricular or facelift skin incision and cervical median
cle is retracted) (IJV: internal jugular vein).                                        skin window.



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E. Crosetti et al.




median skin window. In this step the VITOM-3D allows to                             ment of metastases of head and neck malignant tumours 9.
magnify the vision of the lower part of IV level, increasing                        The surgical technique has changed over time with the in-
the precision of the dissection and haemostatic manoeuvers                          troduction of more conservative approaches, curative and
near the inferior cervical pedicle, phrenic nerve and major                         elective, allowing the preservation of anatomical structures
lymphatic structures.                                                               such as the IJV, accessory spinal nerve, and sternocleido-
                                                                                    mastoid muscle 10.
Dissection of level Ib                                                              Carrying out a neck dissection using the traditional approach
For dissection of level Ib, the first surgeon must be posi-                         does not simply mean the presence of a more or less visible
tioned more caudally, directing surgical instruments crani-                         scar on the neck, but it can expose the patient to more easily
ally. The retractor blade must be positioned medially higher                        acquired and more frequent complications such as cervical
on the skin flap. The assistant also uses a skin hook to pull                       lymphoedema, fibrosis, scar retraction, keloids and wound
up the skin flap. The direction of the exoscope is oriented                         dehiscence, that can have a negative impact on the percep-
more cranially toward the upper part of the neck.                                   tion of the body’s self, especially in young and female pa-
After dissecting the superficial cervical fascia, the subman-                       tients 11. In addition, since the neck dissection is performed in
dibular gland is exposed, and the facial vein is identified on                      combination with transoral surgery in a good percentage of
the surface of its posterior pole. The distal facial pedicle is                     cases, this partly undermines the patient’s perception of the
carefully ligated 1 cm from the inferior margin, thus avoid-                        concept of “mini-invasiveness” of the latter. All this config-
ing inadvertent damage to the mandibular branch of the                              ures the condition of carrying out a truly minimally invasive
VIIth cranial nerve; this manoeuver is made easier by the                           operation on primary carcinoma, with an even greater eco-
excellent 3D vision provided by the exoscope. Submandib-                            nomic weight linked to technological devices, keeping the
ular gland removal begins from the anterior pole. Consider-                         aesthetic and functional cervical sequelae unchanged due to
ing the working distance and the presence of blood vessels                          the open neck approach by dissecting the lymph node areas.
                                                                                    In any case, the aesthetic and functional outcomes after ro-
on the muscular surfaces, it can be very useful to carry out
                                                                                    botic surgery, widely validated in terms of minimal invasive-
this dissection using 24 cm LigaSure Maryland forceps, in
                                                                                    ness and overall lower weight, justify the use of this device
haemostatic mode (Fig. 9).
                                                                                    in the transoral treatment of some primary tumours coupled
Dissection of level Ib is carried out completely under 3D
                                                                                    with a traditional open neck approach.
exoscopic vision and, in our experience, was particularly
                                                                                    In recent years, head and neck oncologic surgery has been
facilitated and precise.
                                                                                    developing various forms of minimally invasive surgical
                                                                                    procedures to increase surgical precision as well as the
Discussion                                                                          satisfaction and quality of life of patients. In 2010, Kang
In 1905, Crile was the first to propose a systematic clas-                          and colleagues first described the so-called RAND (remote
sification of neck dissection. Radical neck dissection has                          access neck dissection), or robot-assisted neck dissection,
historically been the treatment of choice for the manage-                           for the treatment of cervical metastases from thyroid car-
                                                                                    cinoma using a transaxillary approach, similar to that used
                                                                                    for total thyroidectomy 12. Based on these observations,
                                                                                    in 2012, Koh and colleagues proposed the modified ret-
                                                                                    roauricular and facelift approaches for performing robot-
                                                                                    assisted neck dissection, not only of levels II, III, and IV
                                                                                    but also I and V, highlighting the greater ease in dissecting
                                                                                    upper and posterior cervical levels 13. The main limitation
                                                                                    highlighted using this access route was the possibility of
                                                                                    performing the dissection of levels IIb and Va, given the
                                                                                    limited vision of these regions.
                                                                                    Although these access routes cannot be literally defined
                                                                                    as “minimally invasive”, they are not burdened by the im-
                                                                                    pact of the scar, which is virtually invisible and not a de-
                                                                                    cisive factor in the main sequelae of the standard cervical
Figure 9. Surgical view of submandibular gland removal (right side): consid-
ering the working distance and the presence of blood vessels on the muscular
                                                                                    approach; they can therefore be equated as outcomes with
surfaces, it can be very useful to carry out this dissection using a 24 cm LigaS-   currently minimally invasive interventions, referring to
ure Maryland forceps, in haemostatic mode.                                          them as “remote access” interventions.



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Concerning endoscopic-assisted neck dissection, several          3D is an acceptable alternative operating technique per-
drawbacks have been highlighted by many studies 14-17.           forming neck dissection by a retroauricular approach.
These limitations include a reduced range of motion, with        Technically feasible, this technique assures a complete
various collisions between first surgeon and assistant, a        compartment-oriented dissection.
two-dimensional view with a lack of depth perception, im-        No particular difficulties were encountered during dissec-
paired eye-hand coordination, minimal tactile sensation,         tion of levels II and III; these steps are mainly conducted
and a relatively slow learning curve. Another important dis-     under direct vision with 3.5× magnification and with a
advantage of endoscopic neck dissection is the need for the      small percentage (10-20%) of 3D-assisted vision, which is
operator to have sufficient skill in handling the endoscope.     particularly useful for the second surgeon. To facilitate a
The focus of recent research has been shifting towards           straightforward and rapid dissection of levels IV and V, the
greater implementation of the da Vinci surgical robot, as        proposed solution is to combine the retroauricular incision
this technique addresses some drawbacks of endoscopic            with a small incision placed midway between the cricoid
surgery. The robotic surgical system has the advantage of        cartilage and the sternal notch, as is currently used in thy-
a stable three-dimensional binocular magnification, motion       roid surgery. This solution is extremely useful in reducing
scaling, tremor filtration, various degrees of freedom with      the operating time and could be considered an interest-
wrist-like articulated movements, a shorter learning curve,      ing solution during robotic-assisted neck dissection in the
superior surgeon ergonomics and improved instrumental            case of major bleeding which is difficult to manage in the
dexterity. Although robotic surgery undoubtedly has clear        lower anatomic regions of the neck. Furthermore, it results
advantages, comparative studies of endoscopic- and robot-        in a small median lower neck skin incision, transforming
ic-assisted techniques have not been able to illustrate dif-     a scar-free surgical procedure (as the purely RAND tech-
ferences in terms of outcomes from a simple comparison           nique offers) into one with a minor scar, but provides the
of numbers such as blood loss, conversion rate, or recovery      surgeons with great confidence in dissecting areas distant
time 3,4,13,18.                                                  from cutaneous access and, if necessary, quickly convert to
The main disadvantages of robotic-assisted neck dissection       a retroauricular approach into a more comfortable proce-
are the length of the operation, significantly longer than the   dure without paying the price of a major scar in the neck.
standard approach, the need for surgeons to develop skills       It should also be noted that these operations are sometimes
in the field of robotic techniques and the higher overall        associated with a tracheostomy to protect the airway: the
costs of the procedure.                                          same procedure is carried out at the end of the procedure
The recent advent of 3D exoscopic surgery has allowed            by the same service incision. In the same way, in some bor-
interesting technical improvements to be introduced in           derline cases due to comorbidity, thanks to this incision,
head and neck surgery, with technical solutions applicable       access to the trachea can be prepared without opening it.
to cervical dissection, with the aim of enhancing surgical       This creates a pre-tracheotomy situation, which can be eas-
vision through remote access, minimising the costs of the        ily opened to the patient’s bed in the case of major bleeding
procedure in comparison to robotic surgery.                      complications in the postoperative period.
Robotic surgery and VITOM-3D have only one charac-               The hybrid execution of neck dissection under direct and
teristic in common: a high definition optical system (even       exoscopic vision represents a valid alternative to video-as-
though different in optical type and positioning with re-        sisted endoscopic- and robot-assisted techniques. Undoubt-
spect to the working area: in fact, one is a 3D-endoscopic       edly, the need for a second skin incision could underpower
device and its tip reaches near the anatomical structures,       the good aesthetic results of the approach.
while the second is a 3D-endoscopic device placed outside        The characteristics of the VITOM-3D images can be con-
the patient) allowing magnification and improved vision of       sidered very comparable to those of the 3D optics of the da
anatomical sites otherwise difficult to explore without a di-    Vinci surgical robot, with its excellent ability to provide
rect conventional approach. Based on these considerations,       3D visual information which is used to interactively con-
we recently conducted this preclinical investigation in the      trol the exoscope camera. Other advantages are its depth of
cadaver lab focused on approaching conventional neck dis-        field, magnification, and image contrast and colour, allow-
section using a retroauricular incision, and evaluate the ap-    ing direct manipulation of the images of anatomic struc-
plications and usefulness of the Storz 3D Exoscopic Sys-         tures. The most advantageous aspects are represented by
tem during different stages of the surgical procedure. The       the magnification of the anatomic details, for example, the
acronym RAND-3D (3D exoscopic surgery) was coined to             vascularisation.
describe the use of this optical tool in neck dissection.        The system is comfortable to use for surgeons who stay for
The current study in the cadaver lab indicates that RAND-        long periods in a sitting position with the screen in front of



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E. Crosetti et al.




them at eye height: surgery carried out facing a 3D screen is     during surgery, and the necessity to wear 3D glasses for
not bothersome for operators, even for longer procedures.         a prolonged period which can lead to headaches in some
After carrying out the first procedure, the combination of        cases 19-21. In our study, none of the surgeons complained
direct vision and 3D exoscopic vision is very easy to work        of side effects.
with. In fact, adapting and placing a polarised lens over the     Another important aspect to underline is that the RAND-
loupes allowed us to reach a comfortable optical solution.        3D optical tool could be used in preparation for robotic-
Almost without realising it, the surgeons pass from one vi-       assisted neck dissection, both for the fidelity of vision and
sion to another depending on the best visual alternative.         for the logistics that make it more easily transportable in
This continuous comparison between exoscope and loupes            the cadaver lab than the robotic platform.
allowed us to reach some conclusions. VITOM-3D allows
to share the same vision among surgeons, placed on the            Conclusions
same side of the cadaver through a limited skin window,
during the entire procedure. The exoscope is particularly         The primary endpoint of this study was to demonstrate the
useful to the second surgeon during haemostatic manoeu-           effectiveness and feasibility of this technology in retroau-
vers and to place multiple vascular clips in the dissection       ricular or facelift approaches to neck dissection.
of the lower part of IV and V level. 3D visualisation is es-      The preclinical investigations on VITOM-3D-assisted neck
sential during level Ib dissection to better identify each ana-   dissection via a retroauricular approach (RAND-3D) have
tomical structure, whereas it is almost impossible to eas-        demonstrated good. This approach can be used in selected
ily dissect level Ia using this approach, due to the working      cases with a clear cosmetic benefit and representing a valid al-
distance.                                                         ternative to endoscopic- and robotic-assisted neck dissection.
Conventional surgical instruments have been used (no re-          Nevertheless, we have concluded that, with the retroauricu-
quirement to buy other specific instrumentation): it is only      lar approach, it is possible to perform a large part of the
required that the surgical instruments are of suitable length     neck dissection under direct vision, even using a minimally
(minimum 24 cm). Other haemostatic tools can be used              invasive approach. The exoscope is useful because it allows
(e.g. Focus, LigaSure, Thunderbeat) with safety deriving          the second operator, seated on the same side as the first
from complete visual control. These aspects are undoubt-          surgeon, to have a good vision, especially during the dis-
edly an advantage, in terms of immediacy, simplicity of use       section of levels II and III, improving precision during hae-
and lower costs in comparison to robotic surgery.                 mostasis. In our opinion, dissection of level IV exclusively
Furthermore, the 3D exoscope provides the benefit of great        through a retroauricular skin incision is quite unsafe using
utility in the learning process, especially for residents, fel-   this technique because the working space is extremely nar-
lows, students, and OR staff, thanks to the same shared           row. This is the reason why we suggest a median skin “win-
visual experience being available to every operator, and al-      dow” which permits better vision and greater safety in the
ways with wide high-resolution monitors. Both images and          dissection of vascular and lymphatic structures.
video sequences can be stored in high definition, enabling        The preliminary results obtained in the cadaver lab have
surgeons to share videos in didactic sessions, meetings and       led us to propose to the Ethics Committee of our Institute
surgical technique courses. This utility applies not only to      a perspective study focused on the oncological and esthetic
neck dissection, but also to the treatment of primary tu-         results obtained by RAND-3D with more specific evalua-
mours 8.                                                          tions of costs, patient satisfaction, and learning curve. That
At present, in a health policy aimed at reducing costs, it is     study is currently ongoing.
difficult to procure up-to-date technologies. The entire cost     Moreover, we are planning an additional study to compare
of the exoscopic platform is similar to that of an operat-        VITOM-3D and DaVinci systems in carrying out neck dis-
ing microscope with an electromagnetic brake. The cost of         section with retroauricolar approach.
disposables for each surgical procedure is about €40-60,
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