10.14639/0392-100X-N0705
Sinonasal dissection courses have been reported to be effective in teaching sinonasal anatomy to trainees, and in improving surgical skills for trained surgeons. Between 2013 and 2019, a standardised structured questionnaire was handed out to 130 participants of 8 sinonasal dissection courses. Each questionnaire included questions about the medical equipment the surgeons were fitted, and the problems encountered during the dissection. The majority of the participants, regardless of their experience and age, considered uncinectomy and anterior ethmoidectomy as the simplest parts of the dissection, whereas the most complicated step was the approach to the frontal sinus. All participants considered the dissection course as a useful way to improve their medical skills while performing an endoscopic surgery procedure, such as their anatomical knowledge, and confidence with instrumentation and the dissection. Sinonasal dissection courses can be considered to be useful for both trainees and trained surgeons. Improving anatomical knowledge can reduce the occurrence of complications, especially in endoscopic surgery.
application/xml
1827-675X
705
6
en
Stefano Pelucchi
https://creativecommons.org/licenses/by-nc-nd/4.0
ACTA Otorhinolaryngologica Italica
surgery
Are sinonasal dissection courses a valid instrument for endoscopic sinus surgeons? A report on 7-years of experience
Text.Serial.Journal
https://www.actaitalica.it/
40
Rhinology
2021-01-21
2020-02-24
2021-01-21
2021-01-21
1
Stefano Pelucchi
2020
10.14639/0392-100X-N0705
ENT & Audiology Unit, Department of Neuroscience and Rehabilitation, University Hospital of Ferrara, Italy
1827-675X
6
surgery
Are sinonasal dissection courses a valid instrument for endoscopic sinus surgeons? A report on 7-years of experience
https://www.actaitalica.it/article/download/705/493
40
ACTA OTORHINOLARYNGOLOGICA ITALICA 2020;40:415-420; doi: 10.14639/0392-100X-N0705




Rhinology


Are sinonasal dissection courses a valid instrument
for endoscopic sinus surgeons?
A report on 7-years of experience
Corsi di chirurgia endoscopica dei seni paranasali: possono essere considerati un
valido strumento per il training chirurgico? Rapporto su 7 anni di esperienza
Fabio Pagella1,2, Enzo Emanuelli3, Marco Benazzo1,2, Alessandro Pusateri4, Sara Ugolini1,2, Michela Melegatti5,
Andrea Ciorba5, Stefano Pelucchi5
1
 ENT Department, I.R.C.C.S. Policlinico San Matteo-University of Pavia, Italy; 2 ENT Department, University of Pavia, Italy;
3
 Department of Neuroscience, Institute of Otorhinolaryngology, University Hospital of Padova, Italy; 4 ENT and Skull-Base Surgery
Department, Department of Neurosciences, Ospedale Papa Giovanni XXIII, Bergamo, Italy; 5 ENT & Audiology Unit, Department of
Neuroscience and Rehabilitation, University Hospital of Ferrara, Italy


SUMMARY
Sinonasal dissection courses have been reported to be effective in teaching sinonasal
anatomy to trainees, and in improving surgical skills for trained surgeons. Between 2013
and 2019, a standardised structured questionnaire was handed out to 130 participants of
8 sinonasal dissection courses. Each questionnaire included questions about the medical
equipment the surgeons were fitted, and the problems encountered during the dissection.
The majority of the participants, regardless of their experience and age, considered unci-          Received: February 24, 2020
nectomy and anterior ethmoidectomy as the simplest parts of the dissection, whereas the             Accepted: May 30, 2020
most complicated step was the approach to the frontal sinus. All participants considered
the dissection course as a useful way to improve their medical skills while performing an           Correspondence
endoscopic surgery procedure, such as their anatomical knowledge, and confidence with               Andrea Ciorba
instrumentation and the dissection. Sinonasal dissection courses can be considered to be            ENT & Audiology Unit, Department of Neuro-
useful for both trainees and trained surgeons. Improving anatomical knowledge can reduce            science and Rehabilitation, University Hospital of
                                                                                                    Ferrara, via Aldo Moro 8, 44124 Ferrara, Italy
the occurrence of complications, especially in endoscopic surgery.
                                                                                                    Tel. +39 0532 239745
KEY WORDS: endoscopic sinus surgery, functional endoscopic sinus surgery, fess,                     E-mail: andrea.ciorba@unife.it
dissection course, surgery
                                                                                                    Funding
                                                                                                    None.
RIASSUNTO
I corsi di chirurgia endoscopica naso-sinusale sono rivolti sia a giovani specialisti per il        Conflict of interest
training chirurgico, sia a chirurghi più esperti per migliorare le abilità chirurgiche. Ad          The Authors declare no conflict of interest.
un totale di centotrenta (130) partecipanti, ad 8 corsi di dissezione in totale, tra il 2013
e il 2019, è stato somministrato un questionario strutturato standardizzato, comprenden-
te domande sulla strumentazione ricevuta e problemi riscontrati durante la pratica di                 How to cite this article: Pagella F, Emanuelli E,
dissezione.L’uncinectomia e l’etmoidectomia anteriore sono state considerate le procedure             Benazzo M, et al. Are sinonasal dissection cours-
                                                                                                      es a valid instrument for endoscopic sinus sur-
più semplici del corso, dalla maggior parte dei partecipanti, mentre l’approccio al seno
                                                                                                      geons? A report on 7-years of experience. Acta
frontale, indipendentemente dall’esperienza e dall’età, è stato ritenuto il passaggio più             Otorhinolaryngol Ital 2020;40:415-420. https://
complicato. Tutti i partecipanti hanno considerato il corso di dissezione come un mezzo               doi.org/10.14639/0392-100X-N0705
utile per migliorare le loro conoscenze anatomiche, ed il grado di confidenza con la stru-
mentazione e con la dissezione. I corsi di chirurgia endoscopica naso-sinusale sono stati           © Società Italiana di Otorinolaringoiatria
ritenuti utili sia dai giovani specialisti, che dai chirurghi più esperti. Il miglioramento delle   e Chirurgia Cervico-Facciale
conoscenze anatomiche può ridurre efficacemente l’insorgenza di complicazioni indeside-
rate, in particolare per gli approcci endoscopici.                                                                 OPEN ACCESS

PAROLE CHIAVE: chirurgia endoscopica dei seni paranasali, corsi di dissezione,                      This is an open access article distributed in accordance with
chirurgia                                                                                           the CC-BY-NC-ND (Creative Commons Attribution-Non-
                                                                                                    Commercial-NoDerivatives 4.0 International) license. The
                                                                                                    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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F. Pagella et al.




Introduction                                                      same procedure. The surgical steps included uncinectomy
                                                                  and maxillary antrostomy, access to the maxillary sinus via
Sinonasal dissection courses are nowadays an established
                                                                  canine fossa, identification of the ethmoid infundibulum,
and fundamental part of the training of ENT surgeons,
                                                                  the frontal recess and the natural frontal sinus ostium, re-
especially for those who are approaching Endoscopic Si-
                                                                  moval of the ethmoidalis bulla, identification of the basal
nus Surgery (ESS). These courses are important because
                                                                  lamella and the superior turbinate, and opening of the sphe-
of the lack of anatomic facilities or valid simulation tools,
                                                                  noid ostium.
and because of the difficult access to specimens related to a
                                                                  The participants then performed hands-on dissections: an-
number of issues (such as cultural, religious, legal restric-
                                                                  terior and posterior ethmoidectomy; sphenoidotomy (par-
tions) 1,2. Sinonasal dissection courses are able to allow:
                                                                  aseptal and transethmoid pathway); orbital decompression;
(i) understanding of the surgical anatomy; (ii) perception
                                                                  sphenopalatine artery identification. The participants also
of the difficulties and complications that are likely to be en-
                                                                  performed endoscopic medial maxillectomy, access to the
countered by surgeons, which must be handled promptly;
                                                                  sellar and parasellar region and repair techniques for cra-
(iii) improvement of confidence with the endoscopes 3. Dis-
                                                                  nial base defects.
section courses usually begin with a theoretical explanation
of the surgical anatomy of paranasal sinuses and surround-        A structured questionnaire was handed out to the partici-
ing structures, following by hands-on training on cadav-          pants at the end of each course, and they were asked to fill
ers. Dissection courses have been shown to be effective in        it out anonymously (see also Fig. 1 for the questionnaire).
teaching sinonasal anatomy to trainees, as well as in im-
proving surgical skills of trained surgeons and reducing the      Statistical analysis
occurrence of complications during an ESS procedure 4-6.          Data were analysed using SPSS Statistics 17.0 (SPSS Inc.,
Nowadays, the reported risk of complications during an            Chicago, IL, USA). Levels of significance were: p < 0.1*;
ESS procedure ranges from 4 to 17% 7. This percentage             p < 0.05**; n.s.: not statistically significant.
is composed of 5% minor complications, and 0.5-1% of
major complications 8, including orbit injures, I and II cra-     Results
nial nerves, vascular structures (i.e. internal carotid artery,
                                                                  A total of 130 structured questionnaires were submitted
ethmoidal artery) 9.
                                                                  to the participants. The average age of participants was 38
The aim of this paper is to describe the strengths and weak-
                                                                  years (range 27-62 years), and on average they had been
nesses of sinonasal dissection courses during surgical train-
                                                                  practicing ENT for 8.8 years (range 0-35 years). Since the
ing for sinonasal surgery, through the evaluation of ques-
                                                                  questionnaire was performed anonymously, we could not
tionnaire responses given to participants.
                                                                  retrieve information about the M/F ratio.
                                                                  18% of participants declared problems with the instrumen-
Materials and methods                                             tation, mostly due to the lack of specific instruments or be-
One hundred and thirty participants attended a total of 8         cause of malfunctioning instruments.
sinonasal dissection courses between 2013 and 2019 in two         15.5% of participants declared problems with anatomy,
different Italian cities (Arezzo and Verona), and all received    mainly due to a scarce confidence with anatomy and/or lit-
a standardised structured questionnaire. Each questionnaire       tle experience; only a few participants had problems with
included questions about the medical instrumentation the          the dissection, due to lack of experience, difficulty of the
participants were fitted, and the problems encountered dur-       surgical task (such as skull base approach), or poor manual
ing the dissection or dissection practice.                        skills.
Each dissection course had a duration of three days; each         11.7% had problems during the dissection (either due to
day included an introductive theoretical part and hands-on        inexperience or due to performing difficult dissection steps,
training on cadavers.                                             such as the skull base approach; either due to scarce confi-
The introductive theoretical part addressed the following         dence with the anatomy or poor manual ability with instru-
topics: rhinosinusal surgical and radiological anatomy of         ments).
the anterior and posterior compartments; anatomy of the           The results concerning specific dissection steps were also
lacrimal pathway and orbit, anatomy of the sellar region,         analysed:
pterygopalatine fossa and the cranial base as well as the         • 2.3% declared problems with uncinectomy;
vascular anatomy; risks of endoscopic sinus surgery (ESS)         • 2.3% declared problems with anterior ethmoidectomy;
and extended endoscopic endonasal approaches.                     • 27.9% declared problems with posterior ethmoidectomy
Each dissection step was displayed in a short video of the           (the participants complained problems such as the pres-



416
                                                                                        Sinonasal dissection courses for endoscopic sinus surgeons




Figure. 1. Structured questionnaire used during the dissection courses.


   ence of complex anatomy; two surgeons encountered                      The simplest part of the dissection was reported to be un-
   problems due to lack of landmarks; other surgeons de-                  cinectomy (76.4%), followed by antrostomy (11.8%), an-
   clared difficulties due to lack of knowledge of anatomy                terior ethmoidectomy (9.4%), sphenoidotomy (1.6%) and
   and inexperience in dissection; other participants de-                 frontal sinus access (0.8%).
   clared difficulties due to the presence of anatomical vari-            The most difficult part of the dissection was reported to
   ants, such as excessive pneumatisation);                               be access to the fronto-ethmoid recess (37.8%), followed
• 19.38% declared problems with sphenoidotomy (for the                    by posterior ethmoidectomy (22.7%), sphenoidotomy
   same reasons mentioned above);                                         (15.1%), orbital decompression (9.2%) and DCR (3.4%).
• 29.46% declared problems with the access to the                         The participants declared that the best way to acquire surgi-
   fronto-ethmoid (during this dissection step difficulties               cal anatomical knowledge (multiple choice question) was:
   were referred to the complex anatomy of the frontal                    participation (82.4%); assisting in a surgery performed by a
   sinus, lack of landmarks, wide anatomical variability                  well-trained ENT surgeon (36.8%); studying surgical vid-
   of this district and also to the troubles in using angled              eos (36%); studying anatomical videos (31.2%); studying
   optics).                                                               anatomic atlases (33.6%); studying ENT books (14.4%);
Most of the surgeons identified and spared anatomical                     studying anatomy texts (11.2%); using interactive pro-
landmarks; however, several complications occurred dur-                   grammes (8.8%); studying other ENT books (8%).
ing the dissection; in particular, 31.5% of the participants              All participants (100%) were eventually satisfied with the
encountered unwanted complications during the dissection,                 course and would all recommend to other colleagues to
such as orbit lesions (14 participants), meningeal lesions (8             take part in it.
participants), vascular lesions, rhinoliquoral fistula (4 par-            The overall course evaluation obtained an average score of
ticipants) and optic nerve lesions (4 participants).                      1.788 (the range was from 1, maximum score - to 6, mini-



                                                                                                                                            417
F. Pagella et al.




mum score). The overall dissection evaluation obtained an                        my were 15.6% of group 1 and 15.8% of group 2 (p = 0.87).
average score of 1.915 (the range was from 1, maximum                            Participants who declared dissection problems were 11.7%
score - to 6, minimum score).                                                    of group 1, and 13.5% of group 2 (n.s., as p = 0.82) (Tab. I).
We then divided the 130 participants into two groups for                         Concerning problems encountered while performing dif-
statistical analysis, setting a cut-off at the age of 40. On                     ferent steps (Tab. II):
average, those aged ≥ 40 were already more experienced in                        • uncinectomy and anterior ethmoidectomy: 2.6% of
nasal surgery training (see below), according to the partici-                       group 1 and 2.7% of group 2 declared problems for unci-
pants’ declarations within the questionnaire. We therefore                          nectomy; 2.6% of both groups for the anterior ethmoid-
tested the hypothesis that the experience is a determining                          ectomy; p = 0.97 and p = 0.99, respectively;
variable for the surgeon’s practice.                                             • posterior ethmoidectomy: 31.2% of group 1 declared
Fifteen participants did not specify their age in the ques-                         problems vs 26.3% of group 2 (p = 0.59);
tionnaire and were excluded. Hence, group 1 consisted of                         • sphenoidotomy: 34.2% of those of group 2 declared dif-
77 participants (66.95%), aged < 40, with an average ENT                            ficulties in this step, compared to 13% of those of group
practice period of 4.29 years; group 2 consisted of 38 par-                         1, p = 0.007**;
ticipants (33.05%), aged ≥ 40, with an average ENT prac-                         • fronto-ethmoidectomy: 27.3% of group 2 declared diffi-
tice period of 17.29 years.                                                         culties in performing the dissection, compared to 39.5%
Participants who declared problems with using the in-                               of group 1 (n.s, p = 0.18).
struments were 17.1% of group 1 and 15.8% of group 2                             In the end, there are no significant differences between the
(p = 0.86). Participants who declared problems with anato-                       two groups, either related to the total number of unwanted


Table I. Comparison between the overall problems referred by the studied groups.
 Problems with the instruments                                                   Yes n./tot (%)                          No n./tot
 < 40 y.o.                                                                         13/76 (17.1%)                          63/76
 > 40 y.o.                                                                         6/38 (15.8%)                           32/38
 Problems with the anatomy
 < 40 y.o.                                                                         12/77 (15.6%)                          65/77
 > 40 y.o.                                                                         6/38 (15.8%)                           32/38
 Problems with dissection
 < 40 y.o.                                                                          9/77 (11.7%)                          68/77
 > 40 y.o.                                                                          5/37 (13.5%)                          33/37



Table II. Comparison between the complications declared by the studied groups.
 Problems with uncinectomy                                                         Yes n./tot (%)                        No n./tot
 < 40 y.o.                                                                          2/77 (2.6%)                           75/77
 > 40 y.o.                                                                          1/37 (2.7%)                           36/37
 Problems with ant. ethmoidectomy
 < 40 y.o.                                                                          2/77 (2.6%)                           75/77
 > 40 y.o.                                                                          1/38 (2.6%)                           37/38
 Problems with post. ethmoidectomy
 < 40 y.o.                                                                         24/77 (31.2%)                          53/77
 > 40 y.o.                                                                         10/38 (26.3%)                          28/38
 Problems with sphenoidotomy
 < 40 y.o.                                                                          10/77 (13%)                           67/77
 > 40 y.o.                                                                         13/38 (34.2%)                          25/38
 Problems with frontal sinus
 < 40 y.o.                                                                         21/77 (27.3%)                          56/77
 > 40 y.o.                                                                         15/38 (39.5%)                          23/38




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complications (p = 0.92), or to the single type of complica-      Through the evaluation of the data from our study, those in
tions reported.                                                   group 1 (younger surgeons) mainly reported difficulties due
The simplest part of the dissection was uncinectomy for           to the scarce manual ability and because of the presence of
87.7% of those of group 1, and for 72.2% of those of group        an anatomical variant (i.e. excessive pneumatisation).
2; uncinectomy was also reported to be an easier step by the      The analysis highlighted that most of the participants at
younger surgeons, compared to the experienced surgeons.           our sinonasal courses were < 40 years of age (66.95%). It
Other dissection steps, such as antrostomy, anterior ethmoid-     is possible that young surgeons approaching ESS are at-
ectomy, sphenoidotomy, did not show significant differenc-        tracted by many reasons such as: (i) the possibility of learn-
es between the two groups. Lastly, 1.4% of participants in        ing sinonasal surgical anatomy safely; (ii) the opportunity
group 1 considered access to the frontal sinus as the simplest    of improving their confidence with endoscopes, and par-
step, which was not mentioned by any surgeon in group 2.          ticularly with angled optics. In many hospitals’ ordinary
The opposite question was asked to participants: “What            routines, young surgeons have usually a lower chance of
was the most difficult part of the dissection?”, 30% of those     performing sinonasal surgery as first operator than experi-
of group 1 considered the posterior ethmoid as the most           enced surgeons; attending dissection courses can therefore
complex procedure, against 14.3% of the second group              improve their skills in a safe way.
(p = 0.09 *). The sphenoid was voted as the most complex          It is interesting to notice that, according to the results of
procedure by the 8.6% of those of group 1 and by the 22.8%        the study by Braun and Betz 10, our study also showed that:
of those of group 2 (p = 0.06 *).                                 uncinectomy and anterior ethmoidectomy represented the
In the end, 89.6% of those of group 1 declared the dis-           simplest parts of the dissection, regardless of experience
section course to be the best way to acquire the surgical         and age, whereas the most complicated step was considered
anatomical knowledge, compared to the 71.4% of those in           to be the approach to the frontal sinus for all the groups.
group 2 (p = 0.02 *).                                             Concerning sphenoidotomy, it is possible that the differ-
                                                                  ences among the groups are caused by different approaches
Discussion                                                        to this step: young surgeons just performed the minimal/
                                                                  essential approach to the sphenoid sinus, whereas trained
ESS is now widely used by ENT specialists around the world        surgeons performed a complete and functional opening,
to treat inflammatory conditions, malformations and neo-          which exposes to greater risks and complications.
plastic diseases of the nasal cavities and paranasal sinuses.     In the end, no differences were observed between the two
The first steps of ESS are linked to the names of Messerk-        groups, neither concerning the total occurrence rate of
linger, Stammberger and Storz 1; they allowed replacing the       unwanted complications, nor considering the types of un-
previous open technique with considerable advantages from         wanted complications that can occur during the dissection.
prognostic, surgical and therapeutic points of view 2-5.          Despite this, just 31.5% of all participants experienced a
ESS represents the best surgical technique for the treat-         minor or major complication, and thus it is possible to state
ment of nasal cavities and paranasal sinus diseases, which is     that constant practice and exercise are efficient ways to im-
among the most highly complex and variable anatomical dis-        prove ones expertise, reducing the occurrence of compli-
tricts of the human body. One limitation is represented by the    cations for the surgeon approaching ESS surgery and for
two-dimensional vision of the optics, which does not allow        trained surgeons as well.
the depth perception. Anatomical variability of sinuses and       There is no commercially available simulator for ESS that is
potential severe complications (vascular, cerebral as well        particularly successful in simulating the anatomy with force
as neurological) related to this surgery should be however        feed-back so far, as opposed to other areas; a number have been
taken in account when dealing with ESS. For these reasons,        described, but none are available 4,12,13. Participating in a ca-
knowledge of the anatomy of this district is a fundamental        daver course is nonetheless a must in training young surgeons,
prerequisite for safely dealing with the technique.               especially to improve manual abilities in a safe way 4,12,13, de-
Sinonasal dissection courses are nowadays a mandatory             spite difficult access to specimens related to a number of is-
part of the ENT surgeon training, and are even attended by        sues (such as cultural, religious, legal restrictions) 4,12-14.
trained surgeons, in order to improve skills in procedures on
anatomic variants 1,2. Based on other experiences (Braun et
al. 10), the participants were divided into two groups accord-
                                                                  Conclusions
ing to their age and experience (as declared on the question-     In conclusion, the authors believe that hands-on courses
naires), in order to evaluate the problems arising at different   are beneficial and satisfactory for both younger and trained
levels of surgical practice, and along the learning curve.        surgeons, and all the participants were satisfied with the



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course and would all suggest to other colleagues to par-                   7
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