10.14639/0392-100X-suppl.1-43-2023-09
Objective. To establish the safety and effectiveness of subtotal petrosectomy with cochlear implantation in patients affected by chronic middle ear disorders to refractory to previous surgical treatments. Methods. A multicentre, retrospective study was conducted on patients affected by recalcitrant chronic middle ear disorders who underwent cochlear implantation in combination with subtotal petrosectomy. Patients’ details were collected from databases of 11 Italian tertiary referral centres. Additionally, a review of the most updated literature was carried out. Results. 55 patients were included with a mean follow-up time of 44 months. Cholesteatoma was the most common middle ear recurrent pathology and 50.9% of patients had an open cavity. 80% of patients underwent a single stage surgery. One case of explantation for device failure was reported among the 7 patients with post-operative complications. Conclusions. Subtotal petrosectomy with cochlear implantation is a benchmark for management of patients with recalcitrant chronic middle ear disorders. A single stage procedure is the most recommended strategy. Optimal follow-up is still debated. Further studies are required to investigate the role of this surgery in paediatric patients.
text/xml
1827-675X
2611
en
Marco Benazzo
http://creativecommons.org/licenses/by-nc-nd/4.0
ACTA Otorhinolaryngologica Italica
recurrent
Current trends on subtotal petrosectomy with cochlear implantation in recalcitrant chronic middle ear disorders
Text.Serial.Journal
https://www.actaitalica.it/
43
Annual congress report
2023-04-21
2023-04-21
2023-04-28
2023-04-28
S67-S75
1
Marco Benazzo
2023/04/21
10.14639/0392-100X-suppl.1-43-2023-09
S67
Department of Clinical, Surgical, Diagnostic and Pediatric Sciences, University of Pavia, Pavia, Italy; Department of Otorhinolaryngology, University of Pavia, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
1827-675X
recurrent
S75
Current trends on subtotal petrosectomy with cochlear implantation in recalcitrant chronic middle ear disorders
https://www.actaitalica.it/article/download/2611/946
43
ACTA OTORHINOLARYNGOLOGICA ITALICA 2023;43(SUPPL.1):S67-S75; doi: 10.14639/0392-100X-suppl.1-43-2023-09




Otology section


Current trends on subtotal petrosectomy
with cochlear implantation in recalcitrant chronic
middle ear disorders
Attualità in tema di petrosectomia subtotale con impianto cocleare
nelle patologie croniche dell’orecchio medio recalcitranti
Pietro Canzi1,2, Stefano Berrettini3, Andrea Albera4, Maurizio Barbara5, Luca Bruschini3, Andrea Canale4, Elena Carlotto2,
Edoardo Covelli5, Domenico Cuda6, Francesco Dispenza7, Maurizio Falcioni8, Francesca Forli3, Sebastiano Franchella9,
Lorenzo Gaini10, Salvatore Gallina7, Andrea Laborai6, Ruggero Lapenna11, Francesco Lazzerini3, Stefano Malpede2,
Marco Mandalà12, Domenico Minervini2, Enrico Pasanisi8, Giampietro Ricci11, Francesca Viberti12, Diego Zanetti13,14,
Elisabetta Zanoletti9, Marco Benazzo1,2
1
  Department of Clinical, Surgical, Diagnostic and Pediatric Sciences, University of Pavia, Pavia, Italy; 2 Department
of Otorhinolaryngology, University of Pavia, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy; 3 Otolaryngology, Audiology
and Phoniatrics Unit, University of Pisa, Pisa, Italy; 4 Division of Otorhinolaryngology, Department of Surgical Sciences, University of Turin,
Turin, Italy; 5 Department of Neuroscience, Mental Health and Sensory Organs, Faculty of Medicine and Psychology, Sapienza University,
Rome, Italy; 6 Department of Otolaryngology, Guglielmo da Saliceto Hospital, Piacenza, Italy; 7 Department of Biomedicine, Neuroscience
and Advanced Diagnostics, Azienda Ospedaliera Universitaria Policlinico “Paolo Giaccone’’, University of Palermo, Palermo, Italy;
8
  Otorhinolaryngology and Otoneurosurgery Department, University Hospital of Parma, Italy; 9 Department of Neuroscience DNS,
Otolaryngology Section, Padova University, Padova, Italy; 10 Department of Otolaryngology and Head and Neck Surgery, Fondazione
IRCCS Ca’ Granda Ospedale Maggiore Policlinico, Milan, Italy; 11 Department of Surgical and Biomedical Sciences, Section
of Otorhinolaryngology, University of Perugia, Perugia, Italy; 12 Department of Otology and Skull Base Surgery, Azienda Ospedaliera
Universitaria Senese, Siena, Italy; 13 Audiology Unit, Department of Specialistic Surgical Sciences Fondazione IRCCS Ca’ Granda,
Ospedale Maggiore Policlinico Milan, Italy; 14 Department of Clinical Sciences and Community Health University of Milan, Milan, Italy

                                                                                                Received: January 9, 2023
SUMMARY                                                                                         Accepted: January 17, 2023
Objective. To establish the safety and effectiveness of subtotal petrosectomy with cochlear
implantation in patients affected by chronic middle ear disorders to refractory to previous     Correspondence
surgical treatments.                                                                            Stefano Malpede
Methods. A multicentre, retrospective study was conducted on patients affected by re-           University of Pavia, Department of Otorhinolaryn-
calcitrant chronic middle ear disorders who underwent cochlear implantation in combi-           gology, IRCCS Policlinico San Matteo Foundation,
                                                                                                viale C. Golgi 19, 27100 Pavia, Italy
nation with subtotal petrosectomy. Patients’ details were collected from databases of 11
                                                                                                Fax +39 0382 503668
Italian tertiary referral centres. Additionally, a review of the most updated literature was    E-mail: stefano.malpede01@universitadipavia.it
carried out.
Results. 55 patients were included with a mean follow-up time of 44 months. Cholestea-
toma was the most common middle ear recurrent pathology and 50.9% of patients had an              How to cite this article: Canzi P, Berrettini S,
                                                                                                  Albera A, et al. Current trends on subtotal pet-
open cavity. 80% of patients underwent a single stage surgery. One case of explantation for
                                                                                                  rosectomy with cochlear implantation in recalci-
device failure was reported among the 7 patients with post-operative complications.               trant chronic middle ear disorders. Acta Otorhi-
Conclusions. Subtotal petrosectomy with cochlear implantation is a benchmark for man-             nolaryngol Ital 2023;43(SUPPL.1):S67-S75.
agement of patients with recalcitrant chronic middle ear disorders. A single stage procedure      https://doi.org/10.14639/0392-100X-sup-
is the most recommended strategy. Optimal follow-up is still debated. Further studies are         pl.1-43-2023-09
required to investigate the role of this surgery in paediatric patients.
KEY WORDS: subtotal petrosectomy, cochlear implant, cochlear implantation, chronic              © Società Italiana di Otorinolaringoiatria
                                                                                                e Chirurgia Cervico-Facciale
otitis media, chronic middle ear disorders, recalcitrant, refractory, recurrent
                                                                                                               OPEN ACCESS
RIASSUNTO                                                                                       This is an open access article distributed in accordance with
Obiettivo. Stabilire la sicurezza ed efficacia dell’intervento di petrosectomia subtotale con   the CC-BY-NC-ND (Creative Commons Attribution-Non-
posizionamento di impianto cocleare nei pazienti affetti da patologia cronica dell’orecchio     Commercial-NoDerivatives 4.0 International) license. The
                                                                                                article can be used by giving appropriate credit and mentio-
medio refrattaria a precedenti trattamenti chirurgici.
                                                                                                ning the license, but only for non-commercial purposes and
Metodi. È stato svolto uno studio retrospettivo multicentrico riguardante quei pazienti af-     only in the original version. For further information: https://
fetti da patologie croniche dell’orecchio medio recalcitranti, sottoposti a petrosectomia       creativecommons.org/licenses/by-nc-nd/4.0/deed.en




                                                                                                                                                        S67
P. Canzi et al.




subtotale con posizionamento di impianto cocleare. Le informazioni sono state raccolte dai database di 11 centri di riferimento di III livello in
Italia. A complemento, è stata svolta una revisione della più recente letteratura.
Risultati. Nello studio sono stati inclusi 55 pazienti con un follow-up medio di 44 mesi. Il colesteatoma ha rappresentato la più comune pato-
logia ricorrente dell’orecchio medio e il 50,9% dei pazienti aveva una cavità aperta. L’80% dei pazienti è stato sottoposto ad una chirurgia a
singolo stadio. Sette pazienti hanno mostrato complicanze post-operatorie, di cui un caso di espianto.
Conclusioni. L’intervento di petrosectomia subtotale con posizionamento di impianto cocleare rappresenta una tecnica chirurgica di rife-
rimento per la gestione dei pazienti affetti da otite media cronica recalcitrante. L’intervento chirurgico a singolo stadio è la strategia più
frequentemente raccomandata. Il follow-up ottimale è ancora ad oggi oggetto di dibattito. Sono richiesti ulteriori studi per stabilire il ruolo di
questo intervento nei pazienti pediatrici.
PAROLE CHIAVE: petrosectomia subtotale, impianto cocleare, otite media cronica, patologie croniche dell’orecchio medio, recalcitrante,
refrattario, ricorrente



Introduction                                                               (PTA, average of 0.5-1-2-4 kHz), minimum, maximum values
                                                                           and standard deviation (SD) were calculated. Functional gain
In the era of “minimally-invasive surgery”, the increasing                 PTA (calculated as the difference between the post-operative
popularity of subtotal petrosectomy (SP) in patients ad-                   PTA and the pre-operative PTA) was also assessed. Pre-op-
dressed to cochlear implantation may appear anachronistic                  erative study included high-resolution computed tomography
and outdated. Since its first description about 40 years ago 1,2,          (HRCT) and gadolinium-enhanced magnetic resonance imag-
SP has been historically proposed for challenging cases as                 ing (MRI). Post-operative audiological data were collected at
an “end-stage procedure”. SP provides a safe field thanks                  1, 3, 6 and 12 months after surgery. Post-operative HRCT was
to the closure of the external auditory canal (EAC) and eu-                performed if needed.
stachian tube, after meticulous removal of temporal bone
air cells and mastoid cavity obliteration 1. Why is the recent             Review of literature
literature increasingly focusing on this surgical technique?               A narrative review of the literature was conducted using
The answer relies on the opportunity to eradicate middle ear               PubMed. Our aim was to identify publications in which pa-
disorders recalcitrant to previous therapeutic attempts and                tients, affected by chronic middle ear disorders and a previ-
to simultaneously restore the impaired hearing. Nowadays,                  ous history of middle ear surgery, were submitted to COI in
patients previously considered unfit for cochlear implanta-                combination with SP because of disease recurrence. “Sub-
tion and patients addressed to high-risk surgical procedures               total petrosectomy”, “middle ear obliteration” and “coch-
may receive a well-established approach, namely SP, with a                 lear implant” were used as key words. Only English articles
lower percentage of adverse events 3. The aim of the present               were included, while case reports, case series, non-English
work was to analyse the role of SP with cochlear implanta-                 articles and studies published before 2010 were excluded.
tion in chronic middle ear disorders recalcitrant to previous              Papers published by Free et al. 5, Polo et al. 6, and Vashishth
treatments in a multicentre retrospective case series. Results             et al. 7, met our inclusion criteria, and were not included
were compared with literature findings of the last 12 years.               due to a possible overlap of patients with the latest study
                                                                           published by Grinblat et al. 3. Data were retrieved from in-
Materials and methods                                                      formation available from the text and tables presented in
                                                                           each article. All included patients submitted to COI and SP
A national multicentre, retrospective study was conducted on               had history of a previous middle ear surgical procedure.
patients affected by chronic middle ear disorders who under-               Cases in which the middle ear was explicitly referred as
went SP and cochlear implantation after performing one or                  dry or non-discharging were excluded. Patients for whom
more previous middle ear surgeries. SP was defined accord-                 information about the pathological course was not avail-
ing to description of Fisch et al. in 1988 1. Patient data were            able were included. Thus, we intended to exclude patients
collected from the Cochlear implant (COI) databases of 11                  in which the indication for COI and SP was purely audio-
tertiary referral centres between January 2005 and Novem-                  logical and was not supported by a history of recalcitrant
ber 2022. Personal data, pathological, audiological, surgical              chronic middle ear disorder.
history and indications were collected. Further details about
surgery, complications and follow-up examinations were in-
cluded. Complications were classified according to the con-
                                                                           Results
sensus proposed by Hansen et al. 4 All patients underwent                  A total of 55 ears in 55 patients were included. Twenty-
otological examination and pure-tone pre-operative audiologi-              five were males (45.5%) and 30 were females (54.5%); the
cal assessment was available in all cases. Pure tone average               mean age at surgery was 61.6 years (range, 10-82 years).



S68
                                                                                                                       Subtotal petrosectomy with cochlear implantation




Only one paediatric patient was included in the study. Mean                              (TPL CWU, TPL CWD or radical cavity), 2 cases (3.6%)
follow-up time was 44 months (range, 1-132 months).                                      had a contralateral COI, and the remaining 33 patients (60%)
                                                                                         did not undergo any surgical intervention on the contralateral
Pathological and surgical history                                                        ear (Tab. I). The presence of a concomitant nasal pathology
All patients included in our series were affected by a chronic                           was investigated; five of the 55 patients (9.1%) suffered from
middle ear disease, had been submitted to a previous middle                              chronic rhinosinusitis with or without nasal polyposis.
ear surgery, and experienced disease recurrence. Under the
terms “chronic middle ear disorders” we included: chronic                                Pre-operative and post-operative audiological assessment
simple otitis media (COM), chronic suppurative otitis me-                                All patients included were affected by severe to profound
dia (CSOM) and chronic otitis media with cholesteatoma                                   sensorineural hearing loss. Pre-operative mean PTA at pure-
(CCOM). In our series, CCOM was the most common mid-                                     tone audiometry was 114 dB HL (range, 85-120 dB HL;
dle ear recurrent pathology accounting for 28 cases (50.9%),                             SD ± 9.3). Fifteen patients (27.3%) were conventional
whereas 10 patients were affected by COM (18.2%) and                                     hearing aid users whereas 40 patients (72.7%) did not use
17 suffered from CSOM (30.9%). Twenty-seven patients                                     or did not benefit from the use of a hearing aid.
(49.1%) had a history of a previous canal wall up tympano-                               Contralateral ear audiological status assessment highlight-
plasty (TPL CWU); in 28 cases an open cavity was present,                                ed a mean PTA for air conducted sounds of 82.3 dB HL
including 25 (45.4%) canal wall down tympanoplasties (TPL                                (range 35-120 dB HL; SD ± 25.13). Mean PTA for bone
CWD) and 3 (5.4%) radical cavities. Information about con-                               conducted sounds was not calculated for the presence of
tralateral ear surgical status was also available. In 20 patients                        a large variety of hearing disorders. Post-operative re-
(36.4%) there was a history of previous middle ear surgery                               sults showed a mean PTA at 6 months after COI surgery


Table I. Demographics, clinical indications and surgical history.
 Author, year                  Cases Ears Age at               Sex             Chronic middle ear             Previous surgery                   Contralateral ear
                                               surgery                         disorders                                                         surgical history
                                               (average)                       COM       CSOM      CCOM       TPL         TPL        Radical
                                                                                                              CWU         CWD        cavity
 Baranano et al. 2013 8            7         7      59.9 yrs*       N/A        N/A       N/A       N/A        N/A         2          N/A         N/A
 Vincenti et al. 2014 9            9         9      48.3 yrs        F – 5,     N/A       N/A       N/A        N/A         N/A        N/A         Stable mastoid cavity –
                                                                    M–4                                                                          5 ears
 Bernardeschi et al. 2015 10       4         4      65 yrs          N/A        N/A       1         2          N/A         1          N/A         SP + CI – 1 ear
 Casserly et al. 2016 11           2         2      N/A             N/A        N/A       N/A       N/A        N/A         2          N/A         N/A
 Szymanski et al. 2016 12          9         9      70.7 yrs*       F – 7,     N/A       N/A       N/A        2           7          0           N/A
                                                                    M–2
 Altuna et al. 2017 13             3         3      61.3 yrs*       M–3        N/A       N/A       1          0           3          0           N/A
 D’Angelo et al. 2020 14           7         7      57 yrs*         F – 4,     N/A       N/A       N/A        3           3          1           N/A
                                                                    M–3
 Kurkure et al. 2020 15            7         7      N/A             N/A        N/A       N/A       N/A        0           7          0           N/A
 Yoon et al. 2020 16               3         3      62 yrs*         F – 2,     0         3         0          0           3          0           N/A
                                                                    M–1
 Lee et al. 2020 17                2         2      62.5 yrs        F – 1,     0         2         0          0           2          0           N/A
                                                                    M–1
 Grinblat et al. 2020 3            39        39     56.8 yrs*       F – N/A,   N/A       N/A       4          11          9          19          N/A
                                                                    M–3
 Zhang et al. 2021 18              11        11     53.3 yrs*       N/A        7         N/A       4          1           10         0           N/A
 Present study                     55        55     61.6 yrs        F – 30,    10        17        28         27          25         3           • TPL CWU, TPL CWD,
                                                                    M – 25                                                                         radical cavity – 20 ears
                                                                                                                                                 • Contralateral COI – 2
                                                                                                                                                   ears
                                                                                                                                                 • No surgery – 33 ears
CCOM: Chronic Otitis Media with Cholesteatoma; COI: Cochlear Implant; COM: Chronic simple Otitis Media; CSOM: Chronic Suppurative Otitis Media; F: female; M: male; N/A: Not
Available; SP: Subtotal Petrosectomy; TPL CWD: Canal Wall Down Tympanoplasty; TPL CWU: Canal Wall Up Tympanoplasty; *: average value of the whole population of the study, not
specific for the listed cases.




                                                                                                                                                                        S69
P. Canzi et al.




Figure 1. Pre-operative pure tone audiometry. Graphic depiction of PTA for each frequency for both implanted and non-implanted side. Horizontal lines represent
PTA trending line, while vertical lines represent SD for each frequency.




Figure 2. Pre- vs post-operative pure tone audiometry. Graphic depiction of PTA for each frequency for the implanted side, pre-operatively and 6 months after
surgery. Horizontal lines represent PTA trending line, while vertical lines represent SD for each frequency.



S70
                                                                                     Subtotal petrosectomy with cochlear implantation




of 39.9 dB HL (range 18.75-70 dB HL, SD ± 9.7). Mean           (27 patients). Among these, the first HRCT scan was made
PTA functional gain after COI positioning was 74.1 dB HL       12 months after COI surgery in 7 cases (25.9%). Mean
(Figs. 1, 2).                                                  radiological follow-up time was 24 months after surgery.
                                                               From the available medical records, only 4 of 27 patients
Surgery                                                        (14.8%) underwent more than one radiological imaging
Forty-four patients (80%) underwent SP in combina-             during follow-up (Tab. III).
tion with COI positioning (single-stage procedure), while
11 patients (20%) underwent two consecutive surgical           Literature review
procedures: SP followed by COI placement (staged proce-        Tables I, II and III provide a detailed overview of the studies
dure). None of the patients underwent a total petrosectomy.    meeting our inclusion criteria 3,8-18. Twelve articles were iden-
Inflammatory status at time of surgery was also investi-       tified, including 103 patients for a total of 103 ears. Regarding
gated: active middle ear inflammation was present in 15        surgical indications, information about the chronic middle
cases (27.3%), and no inflammation was detected among          ear disorder was available in 24 of 103 cases (23.3%) (Tab. I).
the remaining 40 patients (72.7%). Only one patient who        Of those 24, 7 patients were affected by COM (29.2%), 6 by
underwent a staged procedure showed active middle ear in-      CSOM (25%) and 11 by CCOM (45.8%), making CCOM
flammation at time of surgery (Tab. II). Surgical cavity was   the most observed disease. Information was not available in
obliterated in 49 patients; autologous abdominal fat was       76.7% of cases. Previous surgical details were reported in
used in 46 cavities (83.7%), temporalis muscle in 1 case       86 cases (83.5%). Specifically, among these, 49 underwent a
(1.8%) and hydroxyapatite granules in 2 patients (3.6%).       previous TPL CWD (57%), 17 received TPL CWU (19.8%)
No obliteration material was used in 6 cases (10.9%). Mean     and 20 patients had a previous radical cavity (23.2%). For
surgical time was assessed for both single-stage and staged    the remaining 16.5% of patients, surgical history was not re-
procedures. On average, single-stage surgeries required        corded. Surgical details about contralateral ear were reported
196 minutes, while staged procedures required 221 min-         in 2 papers accounting for only 6 cases (6.9%) among the 86
utes overall. The mean time for SP stage (first stage) was     with an available surgical information. Regarding cochlear
127 minutes, while for COI positioning (second stage) it       implantation, all patients enrolled in the study received a SP
was 94 minutes. The time gap between the surgical stages       (Tab. II). For 80 cases (77.7%), a single stage surgery was
was 7.8 months overall. Further details about COI model        performed, whereas for 9.7% (10 cases) the surgical inter-
and electrode insertion are listed in Table II.                vention was staged. Finally, for 13 cases (12.6%) data about
                                                               surgical staging were not available. Obliteration material of
Complications                                                  the cavity was also assessed, when described. Abdominal fat
Seven of 55 patients (12.7%) experienced surgical com-         was the most common obliteration material used (75 cases of
plications. Among major complications, there was one           103; 72.8%), while in 3 patients the temporalis muscle was
case of abdominal haematoma needing revision surgery           preferred. In 25 cases, details about the obliteration material
and one case of COI failure that occurred 40 months after      were not available. A total of 9 complications were identified
surgery, requiring explantation and reimplantation. Minor      among the included patients (8.7%), and all were classified
complications included 2 cases of EAC closure breakdown        as major according to the proposed criteria of Hansen et al. 4
treated by scarring of the margins of the wound. One case      (Tab. III).
of retroauricular wound infection was treated with antibi-
otic therapy, while another patient required surgical suture
and wound dressings for retroauricular suture dehiscence.
                                                               Discussion
Finally, 1 case of abdominal seroma was reported, but          Constant improvements in the field of cochlear implantation
did not require any specific therapy. Other than the pa-       have been made over the years. Profoundly deaf patients re-
tient who experienced COI failure, the above-mentioned         quire an effective hearing rehabilitation and when deafness is
complications occurred 8.1 days after surgery on average       concomitant with chronic refractory middle ear pathologies,
(range, 1-22 days) (Tab. III). Among the 7 patients who        hearing rehabilitation must be combined with the successful
experienced complications, 3 had an active inflammation        eradication of the disease. While some bone conduction hear-
at time of surgery (42.9%) and none had received a staged      ing implants can be positioned away from an open cavity or a
procedure.                                                     chronically discharging middle ear 19, cochlear implantation in
                                                               these scenarios seems hazardous. SP overcomes these limits,
Radiological follow-up                                         resulting in a “safe and dry” cavity that is optimal for COI
A post-operative HRCT was performed in 49.1% of cases          positioning 5. The efficacy and the advantages of this surgical



                                                                                                                               S71
P. Canzi et al.

Table II. Surgical details.
 Author, year      Cases Ears         Type of              Inflammatory     Staging             Median time Obliteration material           COI model          Electrode
                                      petrosectomy         status at time                       between                                                        insertion
                                                           of surgery                           stages
                                      Subtotal     Total   Active Stable
 Baranano et       7         7        7            0       N/A       N/A    N/A                 N/A           Abdominal fat, temporalis     N/A                N/A
 al. 2013 8                                                                                                   muscle or bone pate – N/A
 Vincenti et al.   9         9        9            0       1         8      Single stage – 8    6 months      Abdominal fat – 9             N/A                Complete
 2014 9
                                                                            Staged – 1
 Bernardeschi      4         4        4            0       4         0      Single stage – 4    /             Abdominal fat – 4             CI24 – 2           Complete
 et al. 2015 10
                                                                                                                                            Digisonic SP – 2
 Casserly et al. 2           2        2            0       2         0      Staged – 2          N/A           Temporalis muscle – 2         N/A                N/A
 2016 11
 Szymanski et      9         9        9            0       4         N/A    Single stage – 8    6 months      Abdominal fat – 9             N/A                N/A
 al. 2016 12
                                                                            Staged – 1
 Altuna et al.     3         3        3            0       1         N/A    Single stage – 3    /             Abdominal fat – 2             N/A                N/A
 2017 13
                                                                                                              Temporalis muscle – 1
 D’Angelo et       7         7        7            0       4         N/A    Single stage – 7    /             Abdominal fat – 7             N/A                N/A
 al. 2020 14
 Kurkure et. al. 7           7        7            0       N/A       N/A    Single stage – 7    /             N/A                           N/A                N/A
 2020 15
 Yoon et al.       3         3        3            0       N/A       N/A    Single stage – 3    /             Abdominal fat – 3             N/A                N/A
 2020 16
 Lee et al.        2         2        2            0       /         2      Single stage – 2    /             Abdominal fat – 2             CI422, CI522       N/A
 2020 17
 Grinblat et al.   39        39       39           0       3*        3*     Single stage – 33   Range 2-9     Abdominal fat – 39            N/A                Complete –
 2020 3                                                                                         months                                                         91.5% (overall)
                                                                            Staged – 1
                                                                            N/A – 5
 Zhang et al.      11        11       11           0       1         N/A    Single stage – 5    2 months – 1 Temporalis muscle ± fascia     N/A                N/A
 2021 18                                                                                                     ± bone paté ± fibroperiostal
                                                                                                             flap – N/A
                                                                            Staged – 5          N/A – 4
                                                                            N/A – 1
 Present study 55            55       55           0       15        40     Single stage – 44   7.8 months    • Abdominal fat – 46          CI422 – 1          Complete – 42
                                                                            Staged – 11                       • Temporalis muscle – 1       CI512 – 4          Non complete – 2
                                                                                                              • Hydroxyapatite granules – 2 CI522 – 1          N/A – 11
                                                                                                              • No obliteration – 6         CI532 – 2
                                                                                                                                            CI612 – 1
                                                                                                                                            CI622 – 2
                                                                                                                                            CI632 – 1
                                                                                                                                            CI24RE – 2
                                                                                                                                            Digisonic SP – 1
                                                                                                                                            Flex 28 – 18
                                                                                                                                            Flexsoft – 1
                                                                                                                                            Form 24 – 1
                                                                                                                                            Hires90k Mid-
                                                                                                                                            scala – 4
                                                                                                                                            Hires90k HiFocus
                                                                                                                                            1J – 1
                                                                                                                                            Sonata – 1
                                                                                                                                            Synchrony
                                                                                                                                            medium – 2
                                                                                                                                            Pulsar – 1
                                                                                                                                            N/A – 11
COI: Cochlear Implant; N/A: Not Available; *: N/A for the other cases.

S72
                                                                                                                                    Subtotal petrosectomy with cochlear implantation

Table III. Complications and follow-up.
 Author, year      Cases Major complications                Minor complications          Onset              Treatment                             Follow-up      Radiological follow-
                                                                                                                                                  time           up
 Baranano et       7       Abscess – 1                      N/A                          N/A                Explantation after 5 months and       N/A            N/A
 al. 2013 8                                                                                                 reimplantation after 2 weeks of
                                                                                                            antibiotic therapy
 Vincenti et al. 9         EAC closure breakdown – 1*       /                            N/A                Rotation skin flap                    144 months     HRCT between 12
 2014 9                                                                                                                                                          and 18 months
 Bernardeschi      4       0                                0                            /                  /                                     21 months      HRCT in all cases
 et al. 2015 10                                                                                                                                                  (timing N/A)
 Casserly et       2       0                                0                            /                  /                                     37 months      HRCT if cholesteatoma
 al. 2016 11                                                                                                                                      (overall)      is suspected
 Szymanski et      9       0                                0                            /                  /                                     36.6 months HRCT at 1 year,
 al. 2016 12                                                                                                                                      (overall)   optional at 3 years
 Altuna et al.     3       Cavity infection – 1             0                            N/A                Explantation                          26 months      2, 5 and 10 years
 2017 13                                                                                                                                          (overall)      with HRCT
 D’Angelo et       7       N/A                              N/A                          N/A                N/A                                   N/A            3 months and 3 years
 al. 2020 14                                                                                                                                                     with HRCT
 Kurkure et.       7       N/A                              N/A                          N/A                N/A                                   37.2 months N/A
 al. 2020 15                                                                                                                                      (overall)
 Yoon et al.       3       0                                0                            /                  /                                     24 months      N/A
 2020 16
 Lee et al.        2       0                                0                            /                  /                                     38 months      1, 3 and 5 years with
 2020 17                                                                                                                                                         HRCT or MRI
 Grinblat et al.   39      a. Postauricular fistula/        0                                a. 12 months   Explantation and reimplantation       85 months      1, 2, 3, 5, 7, 9 years
 2020 3                       receiver exposure – 1                                                         (a, b, c)                             (overall)      with HRCT
                           b. Cavity infection – 1                                        b. 20 months
                           c. Postauricular fistula/                                         c. 11 months
                              receiver exposure – 1
 Zhang et al.      11      a. Electrode exposure – 1        0                            N/A                a. Revision surgery (tragal cartilage 24.2 months N/A
 2021 18                                                                                                       to cover the electrode)            (overall)
                           b. COI exposure – 1                                                              b. COI explantation
                           c. EAC closure breakdown                                                         c. Wound dressing + antibiotics
                              –1
 Present           55      a. Abdominal hematoma – 1        c. EAC closure               • 8.1 days         a. Revision surgery                   44 months      • At 2 years on
 study                                                         breakdown – 2               (average)                                                               average (27 cases)
                           b. COI failure – 1               d. Retroauricular wound      • 40 months b. Explantation and reimplantation                          • N/A for 28 cases
                                                               infection – 1               (COI failure)
                                                            e. Retroauricular suture                        c. Scarring of the margins
                                                               dehiscence – 1
                                                            f. Abdominal seroma – 1                         d. Antibiotic therapy
                                                                                                            e. Medications and suture
                                                                                                            f. None
EAC: External Auditory Canal; COI: Cochlear Implant; HRCT: High-Resolution Computed Tomography; MRI: Magnetic Resonance Imaging; N/A: Not Available; *: classified as a major complication
after review by adopting Hansen et al. criteria.



technique are increasingly acknowledged. However, surgical                                        erature by Polo et al. 6. Based on this evidence, a review of the
management in terms of staging and follow-up still remains                                        most recent literature was carried out to identify all patients af-
controversial 20. Middle ear surgery failures are undeniably                                      fected by chronic middle ear disorders with a history of failed
affected by the clinical behaviour of chronic middle ear pa-                                      prior surgery. According to our literature review, CCOM is
thologies over time. This tight clinical-surgical relationship                                    the most common indication for SP (11 of 24 cases, 45.8%),
led us to collect one of the largest series of patients submitted                                 which is consistent with the results from our series (50.9% of
to SP in combination with cochlear implantation. In fact, data                                    cases). Concerning previous surgical history, surprisingly, al-
from the literature show that personal history of otitis media                                    most half of patients in our cohort had a history of TPL CWU
accounts for 55.4% of indications for SP and the presence of                                      (49.1%), compared to only 19.8% of patients in the literature
a mastoid cavity accounts for 35.5%. This makes these two                                         who underwent this type of surgery before SP and COI. Of
entities the first and second most common indications for SP,                                     note, the literature does not usually report the surgical history
as previously observed in the one of the largest studies in lit-                                  of patients with middle ear diseases, and thus the results ob-



                                                                                                                                                                                     S73
P. Canzi et al.




tained from our review can be underestimated. Postelmans et            native surgical approaches. In particular, the risk of array
al. 21 proposed a decisional algorithm based on the presence           extrusion is lower in SP than in revision mastoidectomy
or absence of active middle ear inflammation in order to solve         approaches and the technique is more feasible compared
one of the main controversies in surgical management. As a             to approaches that bypass the middle ear like the middle
rule, all patients with evidence of active middle ear inflamma-        cranial fossa one 12,21,24. In our multicentric case series, only
tion were staged and none experienced post-operative compli-           12.7% of patients experienced complications, which is un-
cations. This is consistent with our experience, in which none         deniably lower compared to patients who underwent CWD
of the patients who underwent staged procedures experienced            tympanoplasty with cochlear implantation (30% according
complications. However, the main reason prompting staged               to Hunter et al.) 24. An additional, non-negligible benefit
surgery was not the presence of active inflammation, but               given by SP is quality of life improvement in terms of clini-
the evidence of CCOM (9 of 11 staged SP were affected by               cal follow-up and daily living (swimming, vertigo induced
CCOM). In fact, 11 of 14 patients with signs of active inflam-         by pressure or temperature changes) 24.
mation underwent a single stage procedure without experienc-           The multicentric nature of this study may be considered
ing adverse events. Conversely, it is worth noticing that the          a limitation in terms of heterogeneity of the series. Many
other 3 cases with active inflammation at time of surgery were         studies included in our review failed to provide adequate
among the 7 with post-operative complications. The absence             information about previous surgical history, contralateral
of complications among the staged patients is an indicator of          ear status, COI model, or concomitant nasal pathology.
the safety of staged surgeries. In our opinion, there is no in-
terdependence between the presence of active inflammation
                                                                       Conclusions
and post-operative complications development. This hypoth-
esis was confirmed by Grinblat et al. in in whose experience           In patients with chronic middle ear disorders recalcitrant to
complications occurred predominantly in patients with inac-            previous treatments, SP with cochlear implantation is a safe
tive inflammatory status 3. The timing of staging in our series        and effective approach for disease eradication and simul-
was 7.8 months on average. This was consistent with litera-            taneous hearing rehabilitation. A single stage procedure is
ture in which second stage surgery was usually performed at            the most recommended strategy. Staging is advocated when
6 months 7,9,12. Six months is the estimated time interval for         CCOM is present rather than in cases of active inflammation.
small residual pearls of cholesteatoma to manifest, which              Optimal follow-up, in terms of timing and imaging tech-
might have gone undetected during surgery 12. Autologous ab-           nique, is still debated. The usefulness of SP for the paediatric
dominal fat was, by far, the most preferred among obliteration         population and its application along with implantable hear-
materials for the surgical cavity. It was chosen in 72.8% of           ing devices (e.g. transcutaneous bone conduction implants,
cases in our review and in 83.7% of patients in our series. The        active middle ear implants) should be the object of further
main reasons are the low metabolic rate and easy accessibil-           investigation.
ity for grafting, as well as the creation of a radiological visual
interface that enables better recognition of indirect signs of         Conflict of interest statement
cholesteatoma at HRCT 5,6,20. More specifically, MRI-induced           The authors declare no conflict of interest.
artifacts produced by a COI do not allow to check for chole-
steatoma recurrences: even if tailored COI positioning makes           Funding
it feasible to monitor specific intracranial structures, its role in   This research did not receive any specific grant from fund-
cholesteatoma detection is still debated 22,23. The use of HRCT        ing agencies in the public, commercial, or not-for-profit
on a cavity obliterated with abdominal fat partially overcomes         sectors.
this limit even though the timing of radiological follow-up is
controversial. Gruppo Otologico 5-7 has proposed a HRCT fol-           Author contributions
low up at 1, 3, 5 and 10 years, while Vincenti et al. 9 advocate       PC, SM, SB, MBE: conception and design of the study, ac-
the execution of a HRCT from 12 to 18 months after surgery             quisition and interpretation of data, drafting of the article,
for reference and a second scan only in the presence of alarm-         literature revision, critical revision for important intellectu-
ing symptoms. In our retrospective series, 49.1% of patients           al content and final approval of the version to be published.
had a post-operative HRCT at a mean time of 24 months after            LB, FF, FL, DM: conception and design of the study, acquisi-
surgery and no recurrences of cholesteatoma were observed              tion of data and final approval of the version to be published.
during follow-up (44 months on average).                               AA, MBA, AC, EC, EC, DC, FD, MF, SF, LG, SG, AL, RL,
As reported in the literature, SP provides better results in           MM, EP, GR, FV, DZ, EZ: acquisition of data and final ap-
terms of surgical risks and complications than other alter-            proval of the version to be published.



S74
                                                                                                           Subtotal petrosectomy with cochlear implantation




Ethical consideration                                                           11
                                                                                     Casserly P, Friedland PL, Atlas MD. The role of subtotal petrosec-
                                                                                     tomy in cochlear implantation. J Laryngol Otol 2016;130:S35-S40.
This study was approved by the Institutional Ethics Com-                             https://doi.org/10.1017/S0022215116000979
mittee of the IRCCS Policlinico San Matteo, Pavia (IRB#                         12
                                                                                     Szymański M, Ataide A, Linder T. The use of subtotal petrosec-
0062983/22). The research was conducted ethically, with                              tomy in cochlear implant candidates with chronic otitis media. Eur
all study procedures being performed in accordance with                              Arch Otorhinolaryngol 2016;273:363-370. https://doi.org/10.1007/
                                                                                     s00405-015-3573-1
the requirements of the World Medical Association’s Dec-                        13
                                                                                     Altuna X, García L, Martínez Z, et al. The role of subtotal petro-
laration of Helsinki. Written informed consent was ob-                               sectomy in cochlear implant recipients. Eur Arch Otorhinolaryngol
tained from each volunteer for study participation and data                          2017;274:4149-4153. https://doi.org/10.1007/s00405-017-4762-x
publication.                                                                    14
                                                                                     D’angelo G, Donati G, Bacciu A, et al. Subtotal petrosectomy and
                                                                                     cochlear implantation. Acta Otorhinolaryngol Ital 2020;40:450-456.
                                                                                     https://doi.org/10.14639/0392-100X-N0931
References                                                                      15
                                                                                     Kurkure R, Rayamajhi P, Castellino A, et al. Subtotal petrosec-
                                                                                     tomy in cochlear implant surgery: our experience. Indian J Otolar-
1
     Fisch U, Mattox DE. Microsurgery of the Skull Base. First edition.
                                                                                     yngol Head Neck Surg 2020;72:320-325. https://doi.org/10.1007/
     Thieme-Verlag; 1988.                                                            s12070-020-01819-8
2
     Gacek RR. Mastoid and middle ear cavity obliteration for control of        16
                                                                                     Yoon YH, Lee J Bin, Chung JH, et al. Cochlear implantation in pa-
     otitis media. Ann Otol Rhinol Laryngol 1976;85:305-309. https://doi.            tients with chronic suppurative otitis media: surgical outcomes and
     org/10.1177/000348947608500301                                                  a management algorithm. Audiol Neurotol 2020;25:151-157. https://
3
     Grinblat G, Vlad Di, Caruso A, et al. Evaluation of subtotal petro-             doi.org/10.1159/000505509
     sectomy technique in difficult cases of cochlear implantation. Audiol      17
                                                                                     Lee S, Lee J Bin, Chung JH, et al. Surgical outcomes of simul-
     Neurotol 2020;25:323-335. https://doi.org/10.1159/000507419                     taneous cochlear implantation with subtotal petrosectomy. Au-
4
     Hansen S, Anthonsen K, Stangerup SE, et al. Unexpected findings                 ris Nasus Larynx 2020;47:943-949. https://doi.org/10.1016/j.
     and surgical complications in 505 consecutive cochlear implantations:           anl.2020.05.009
     A proposal for reporting consensus. Acta Otolaryngol 2010;130:540-         18
                                                                                     Zhang K, Yan F, Nguyen SA, et al. Subtotal petrosectomy with coch-
     549. https://doi.org/10.3109/00016480903358261                                  lear implantation or osseointegrated hearing rehabilitation: a single
5
     Free RH, Falcioni M, Di Trapani G, et al. The role of subtotal pet-             institutional study. Otol Neurotol 2021;42:1499-1506. https://doi.
     rosectomy in cochlear implant surgery-a report of 32 cases and re-              org/10.1097/MAO.0000000000003326
     view on indications. Otol Neurotol 2013;34:1033-1040. https://doi.         19
                                                                                     Canzi P, Avato I, Beltrame M, et al. Retrosigmoidal placement of an
     org/10.1097/MAO.0b013e318289841b                                                active transcutaneous bone conduction implant: surgical and audio-
                                                                                     logical perspectives in a multicentre study. Acta Otorhinolaryngol Ital
6
     Polo R, Del Mar Medina M, Arístegui M, et al. Subtotal pet-
                                                                                     2021;41:91-99. https://doi.org/10.14639/0392-100X-N0609
     rosectomy for cochlear implantation: lessons learned after 110
     cases. Ann Otol Rhinol Laryngol 2016;125:485-494. https://doi.
                                                                                20
                                                                                     Yan F, Reddy PD, Isaac MJ, et al. Subtotal petrosectomy and coch-
     org/10.1177/0003489415620427                                                    lear implantation: a systematic review and meta-analysis. JAMA Oto-
                                                                                     laryngol Head Neck Surg 2021;147:23-33. https://doi.org/10.1001/
7
     Vashishth A, Fulcheri A, Prasad SC, et al. Cochlear implantation in             jamaoto.2020.3380
     cochlear ossification: retrospective review of etiologies, surgical con-
     siderations, and auditory outcomes. Otol Neurotol 2018;39:17-28.
                                                                                21
                                                                                     Postelmans JTF, Stokroos RJ, Linmans JJ, et al. Cochlear implan-
                                                                                     tation in patients with chronic otitis media: 7 years’ experience in
     https://doi.org/10.1097/MAO.0000000000001613
                                                                                     Maastricht. Eur Arch Otorhinolaryngol 2009;266:1159-1165. https://
8
     Barañano CF, Kopelovich JC, Dunn CC, et al. Subtotal petrosectomy               doi.org/10.1007/s00405-008-0842-2
     and mastoid obliteration in adult and pediatric cochlear implant re-       22
                                                                                     Canzi P, Magnetto M, Simoncelli A, et al. The role of cochlear im-
     cipients. Otol Neurotol 2013;34:1656-1659. https://doi.org/10.1097/             plant positioning on MR imaging quality: a preclinical in vivo study
     MAO.0b013e3182a006b6                                                            with a novel implant magnet system. Eur Arch Otorhinolaryngol
9
     Vincenti V, Pasanisi E, Bacciu A, et al. Long-term results of external          2022;279:2889-2898. https://doi.org/10.1007/s00405-021-07005-y
     auditory canal closure and mastoid obliteration in cochlear implanta-      23
                                                                                     Canzi P, Luzzi S, Carlotto E, et al. Customized cochlear implant po-
     tion after radical mastoidectomy: a clinical and radiological study. Eur        sitioning in a patient with a low-grade glioma: towards the best MRI
     Arch Otorhinolaryngol 2014;271:2127-2130. https://doi.org/10.1007/              artifact management. Otol Neurotol 2022;43:E628-E634. https://doi.
     s00405-013-2698-3                                                               org/10.1097/MAO.0000000000003532
10
     Bernardeschi D, Nguyen Y, Smail M, et al. Middle ear and mastoid           24
                                                                                     Hunter JB, O’Connell BP, Wanna GB. Systematic review and meta-
     obliteration for cochlear implant in adults: indications and anatomi-           analysis of surgical complications following cochlear implantation
     cal results. Otol Neurotol 2015;36:604-609. https://doi.org/10.1097/            in canal wall down mastoid cavities. Otolaryngol Head Neck Surg
     MAO.0000000000000702                                                            2016;155:555-563. https://doi.org/10.1177/0194599816651239




                                                                                                                                                      S75
