The authors would like to thank Collin Medical, Bagneux, France, for their support and la Fondation des Gueules Cass&#233;es who helped finance the acquisition of the RobOtol at H&#244;pital Necker - Enfants Malades, APHP.

This study was conducted in compliance with the European GDPR and registered at AP-HP, H&#244;pital Necker - Enfants Malades (number 20200727144143). The study adhered to the CARE guidelines12, and both parents provided written consent to record the surgical video of the procedure and to publish a case report13,14. The surgical strategy mirrored the one typically used in our tertiary referral center with a microscope, involving the use of both hands. The primary difference was the surgical approach, which was trans-canal, eliminating the need for atticotomy or canalplasty.
1. Pre-operative procedures
<ol>
	<li>Diagnose congenital cholesteatoma during otoscopy in the clinic, where a white mass is visible behind a normal tympanic membrane. Discuss the tympanoplasty procedure and approach with the parents (and the patient, considering their age), explaining the benefits and risks.</li>
	<li>Check the pre-operative auditory work-up to assess ossicular involvement in cases of conductive hearing loss and to verify the absence of associated sensorineural hearing loss.</li>
	<li>Prepare for the tympanoplasty procedure with a pre-operative CT scan to assess the feasibility of total endoscopic ear surgery (TEES) and to check for mastoid involvement. 
	NOTE: Ossicular involvement can also be assessed to determine the Potsic stage3. Stage I and II patients are ideal candidates for TEES, while stage III cases may be more challenging due to the difficulty of safely dissecting the ossicular chain with one hand. Potsic stage IV lesions require mastoidectomy, and a traditional endaural or postauricular approach is usually preferred.</li>
	<li>Assess the size of the external ear canal using a speculum (see Table of Materials), which is particularly important in infants. 
	&#8203;NOTE: If a size 4 speculum can be inserted, TEES can be easily performed. It is more challenging but still possible to perform TEES if a size 3 speculum can be inserted (the canal is between 3 and 4 mm wide at its narrowest).</li>
</ol>
2. Preparation for the surgery
<ol>
	<li>Perform a checklist to confirm the side of the lesion and ensure that a CT scan and audiometry results are available before commencing the procedure.</li>
	<li>Install the robotic arm (endoscope holder) (see Table of Materials) on the robot and ensure it is in a neutral position.</li>
	<li>After patient intubation13,14, tilt the patient&#39;s head and secure it in a 30&#176; rotation away from the surgeon. Tilt the patient&#39;s headrest backward and incline the surgical bed in an anti-Trendelenburg position to position the patient&#39;s head horizontally.</li>
	<li>Secure the patient&#39;s head to the table using an adhesive elastic band placed on the forehead.</li>
	<li>Set up facial nerve monitoring (see Table of Materials).</li>
	<li>Drape the surgical microscope, at least for the initial procedures, to facilitate a transition to the microscope during the procedure if difficulties arise with the robot. 
	NOTE: This is essential to ensure the highest quality of patient care while still advancing along the learning curve.</li>
	<li>Drape the robotic arm and the robot.</li>
	<li>Install and drape the space mouse after attaching it to the surgical bed next to the surgeon (see Figure 1), which controls the robotic arm&#39;s multi-directional movement. 
	NOTE: The space mouse can be fixed on either side of the surgeon, but in this studt, it&#39;s positioned toward the patient&#39;s feet, allowing the surgeon to sit directly next to the scrub nurse (who is positioned at the head of the patient, as shown in Figure 2).</li>
	<li>Disinfect the surgical site and cover it with surgical drapes, exposing only the external ear.</li>
	<li>Position the robot opposite the surgeon (on the other side of the bed) so that the robotic arm (endoscope holder) can extend over the patient&#39;s head toward the surgeon, aligning with the external auditory canal (as illustrated in Figure 1).</li>
	<li>Place the video tower opposite the surgeon, preferably on either side of the robot (ideally toward the patient&#39;s feet), ensuring a comfortable view of the screen. For a left tympanoplasty, position the video tower to the right of the robot (as shown in Figure 1 and Figure 2).</li>
</ol>
3. Onset of the surgery
<ol>
	<li>Position the endoscope holder over the auditory canal meatus and insert the endoscope into the endoscope holder. Use a 25 cm long telescope with the robotic arm to reduce the risk of conflicts with the surgeon&#39;s hands during the procedure. 
	NOTE: The telescope has a width of 2.9 mm, and a 0&#176; scope is typically used, although 30&#176; or 45&#176; scopes may be useful for certain steps.</li>
	<li>Clean and disinfect the ear canal, and carefully examine the tympanic membrane.</li>
	<li>Administer local anesthesia (using a solution containing 10 mg/mL xylocaine and 0.005 mg/mL adrenaline) to the upper portion of the bony auditory canal (vascular strip).</li>
	<li>Harvest tragal cartilage (conchal cartilage can be used as an alternative). Place a small gauze in the ear canal during this stage to prevent the accumulation of coagulated blood.</li>
</ol>
4. Congenital cholesteatoma (CC) procedure
<ol>
	<li>Make an incision from 12 o&#39;clock to 8 o&#39;clock for the trans-canal approach using an angled cautery needle with low power (4 Watts) (see Table of Materials) to prevent retraction. Use suction to clear any smoke or blood that may obstruct the view.
	<ol>
		<li>Open the tympanic cavity inferiorly, posteriorly, and superiorly along the chorda tympani until the malleus neck is identified. 
		NOTE: Extend the skin incision if there is tension in the flap to prevent tearing.</li>
	</ol>
	</li>
	<li>Identify and debulk the lesion: ensure that the posterior portion of the congenital cholesteatoma (CC) is clearly visible, and its involvement with the incus and stapes can be accurately assessed.
	<ol>
		<li>Elevate the tympanum from the manubrium to push the tympano-meatal flap anteriorly. Open the CC matrix in the controllable posterior-inferior portion and debulk it using a large suction. 
		NOTE: A stage III CC is typically too large to be removed without inducing ossicular trauma or the risk of dislocation.</li>
	</ol>
	</li>
	<li>Separate the CC from the incus and stapes using a hook or needle and push it anteriorly under the malleus with a Fisch microdissector (see Table of Materials). 
	NOTE: Exercise great care to avoid ossicular trauma, and use suction as a counterforce to stabilize the ossicles during dissection.</li>
	<li>Dissect the CC from the promontory and cochleariform process and remove the CC. 
	NOTE: Be especially cautious when dissecting the medial-anterior side of the malleus, using a hook or Fisch microdissector.</li>
	<li>Inspect the tympanic cavity using an angled endoscope. 
	NOTE: With an intact ossicular chain, the endoscope must be manipulated very cautiously, especially with an angled view. Robotic control of the endoscope is highly useful for rotating it 360&#176; while maintaining the shaft in the same position and at the exact same depth. To inspect the ossicles, use a soap-soaked cotton ball to wipe the medial side of the malleus and incus and between the crus of the stapes to detect any residual squamous cells15.</li>
	<li>Reinforce the tympanic membrane and insert cartilage in an underlay position to prevent subsequent retraction pockets. Replace the tympano-meatal flap on the bony canal and pack it with absorbable foam, starting with the anterior part of the tympanum to avoid any subsequent lateralisation.</li>
	<li>Discharge the patient according to an outpatient protocol. Administer auricular antibiotic drops for three weeks and schedule a post-operative check-up at one month. 
	NOTE: No external dressing is necessary.</li>
</ol>

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J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=The+CARE+guidelines:+consensus-based+clinical+case+reporting+guideline+development.">The CARE guidelines: consensus-based clinical case reporting guideline development.</a> BMJ Case Reports. 2013, bcr2013201554 (2013).</li><li>Simon, F., Jankowski, R., Laccourreye, O. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Consent+and+case+reports.">Consent and case reports.</a> European Annals of Otorhinolaryngology, Head and Neck Diseases. 139 (4), 175-176 (2021).</li><li>Simon, F., Laccourreye, O., Jankowski, R., Maisonneuve, H. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Videos+in+otorhinolaryngology.">Videos in otorhinolaryngology.</a> European Annals of Otorhinolaryngology, Head and Neck Diseases. 138 (5), 325-326 (2020).</li><li>Gyo, K., Sasaki, Y. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Solubilization+of+keratin+debris+in+conservative+treatment+of+middle+ear+cholesteatoma:+an+in+vitro+study.">Solubilization of keratin debris in conservative treatment of middle ear cholesteatoma: an in vitro study.</a> The Journal of Laryngology and Otology. 108 (2), 113-115 (1994).</li><li>Khan, M. M., Parab, S. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Endoscopic+cartilage+tympanoplasty:+A+two-handed+technique+using+an+endoscope+holder.">Endoscopic cartilage tympanoplasty: A two-handed technique using an endoscope holder.</a> The Laryngoscope. 126 (8), 1893-1898 (2016).</li><li>Khan, M. M., Parab, S. R. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Novel+concept+of+attaching+endoscope+holder+to+microscope+for+two+handed+endoscopic+tympanoplasty.">Novel concept of attaching endoscope holder to microscope for two handed endoscopic tympanoplasty.</a> Indian Journal of Otolaryngology and Head and Neck Surgery: Official Publication of the Association of Otolaryngologists of India. 68 (2), 230-240 (2016).</li><li>De Zinis, L. O. R., Berlucchi, M., Nassif, N. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Double-handed+endoscopic+myringoplasty+with+a+holding+system+in+children:+Preliminary+observations.">Double-handed endoscopic myringoplasty with a holding system in children: Preliminary observations.</a> International Journal of Pediatric Otorhinolaryngology. 96, 127-130 (2017).</li><li>Jain, A., Dion, G. R., Howell, R. J., Friedman, A. D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+novel+rigid+telescope+holder+for+endoscopic+surgery+in+otolaryngology.">A novel rigid telescope holder for endoscopic surgery in otolaryngology.</a> The Annals of Otology, Rhinology, and Laryngology. , 34894231206898 (2023).</li><li>Michel, G., Bordure, P., Chablat, D. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=A+new+robotic+endoscope+holder+for+ear+and+sinus+surgery+with+an+integrated+safety+device.">A new robotic endoscope holder for ear and sinus surgery with an integrated safety device.</a> Sensors. 22 (14), 5175 (2022).</li><li>Berges, A. J., et al. <a target="_blank" href="http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?db=PubMed&cmd=Search&doptcmdl=Citation&defaultField=Title+Word&term=Characterization+of+patient+head+motion+in+otologic+surgery:+Implications+for+TEES.">Characterization of patient head motion in otologic surgery: Implications for TEES.</a> American Journal of Otolaryngology. 42 (2), 102875 (2021).</li></ol>

Yann Nguyen is a consultant for Collin Medical, Bagneux, France. The others authors have no conflicts of interest to declare.

This study reports the successful use of a robot-assisted totally endoscopic procedure to remove a stage III congenital cholesteatoma in a 3-year-old child. Total endoscopic ear surgery (TEES) is particularly interesting in the pediatric population, as performing tympanoplasties with a keyhole trans-canal approach reduces healing time and the amount of immediate post-operative care. Regarding cholesteatoma surgery, many studies have now demonstrated that TEES yields similar, if not smaller, residual rates in selected patients compared to microscopic postauricular or endaural approaches4,5,10.
Stage I or II congenital cholesteatoma (CC) are, of course, ideal cases for TEES, with excellent results. In these cases, there is no ossicular involvement, visibility is often excellent, and the CC does not extend into high-risk areas of residual disease, such as the retrotympanum or anterior epitympanum4,5,6,7,8. Difficulties may arise in stage III or IV CC, where dissecting ossicles or removing extensive lesions is required with only one hand. In traditional microscopic two-handed surgery, the second hand typically holds a suction device, which can enhance vision by removing blood but also plays a key role in tissue manipulation and ossicular control during dissection.
The robotic endoscope holder represents an innovative and secure solution to combine the advantages of TEES with a two-handed procedure11. This case report demonstrates the feasibility of using this technology in a young 3-year-old child, where a 2.9 mm endoscope, two instruments, and sufficient working space could be accommodated within the child&#39;s narrow external auditory canal, enabling work on the stapes and exploration of the epitympanum.
Other systems have been used to combine endoscopic vision with a two-handed approach, facilitating bi-manual manipulation of grafts and prostheses or blood suction16,17,18,19,20. Although some steps during TEES that require a second operative hand can be done with the assistance of another individual (holding the camera or suction), endoscope holders make the entire TEES procedure feasible with two hands, which can be advantageous for surgeons accustomed to this configuration with the microscope. Rigid mechanical endoscope holders may be suitable for short and simple type 1 myringoplasties18, but they restrict movement, preventing the surgeon from quickly approaching the surgical field or adjusting the view. Therefore, dynamic holders, such as robotic endoscope holders, offer dynamic movement as well as the best precision and security compared to other manually-set dynamic holders16,20, particularly in a middle ear with an intact ossicular chain. Dangerous head movements may occur during otologic procedures, posing a risk of significant trauma during TEES21. As in most otology procedures near the oval window, we recommend securing the head with an adhesive elastic band (as detailed in step 2.4) since the robotic arm cannot automatically move with the patient&#39;s head.
The main limitation of the robotic method is the very narrow ear canal in children with craniofacial anomalies (such as Down syndrome), which may render it impossible to simultaneously insert the endoscope and two hand-held instruments. Additionally, diseases that extend posteriorly beyond the lateral semicircular canal may necessitate a larger incision. As previously mentioned (see steps 1.3 and 1.4), careful pre-operative planning and the insertion of a size 3 speculum enable the selection of appropriate candidates for the technique.
Robotic-assisted TEES presents a promising option to expand the use of TEES to complex middle ear lesions while benefiting from the advantages of two-handed surgery and dynamic intra-operative movement. The procedure was successful without adding extra surgical time. A large-scale study on a cohort of patients is required to more precisely determine the limits of robot-assisted TEES and discuss its indications compared to traditional microscopic surgery and one-handed TEES.

Congenital cholesteatoma (CC) accounts for 25% of cholesteatoma cases in children, and its proportion within cholesteatoma cases has increased in recent years due to improved public health measures and earlier detection worldwide1,2. The size and ossicular involvement of CC significantly impact the prognosis and surgical strategy. As a result, CC can be classified according to the Potsic classification3. When diagnosed early, these lesions are typically confined to the tympanic cavity or may extend to the epitympanum with an intact matrix, involving the ossicles (Potsic stage III) or not (Potsic stage I or II). In more advanced cases, distinguishing CC from acquired cholesteatomas can be challenging, with diffluent lesions in the epitympanum or mastoid regions and altered tympanic membranes (Potsic stage IV).
Patients with CC without mastoid involvement (Potsic stage I to III) make excellent candidates for total endoscopic ear surgery (TEES), which involves a minimal trans-canal incision and offers an excellent view of the entire tympanic cavity and epitympanic region. Numerous studies have demonstrated that TEES yields similar residual rates compared to the traditional microscopic approach4,5,6,7,8,9. TEES has been adopted by many pediatric otology centers worldwide, providing a safe and efficient technique that also enhances ergonomics for surgeons, allowing them to sit upright while facing the screen5,7,8,10. However, during TEES, safely dissecting the ossicles can be challenging in stage III lesions due to the lack of counter-stabilization when using an instrument in the second hand, increasing the risk of ossicular subluxation and inner ear trauma from excessive ossicle mobilization. Additionally, the lack of suction during dissection can lead to poor visibility due to bleeding or endoscope fogging. A robotic arm designed for middle ear surgery and cochlear implantation has been employed as a robotic dynamic endoscope holder, providing six degrees of freedom, including three translational and three rotational axes throughout the procedure. Its safety during robot-assisted TEES has already been reported in the adult population11.
This article reports the robotic setup and surgical procedure for a stage III congenital cholesteatoma in a 3-year-old child, using robotic-assisted TEES. This approach allows for the dissection of the cholesteatoma with two hands while benefiting from an endoscopic view and a trans-canal approach.

<table><tbody><tr><td>0&amp;deg; 2.9 mm 25 cm Endoscope</td><td>Collin</td><td>RBT-END-0</td><td>Endoscope for otoendoscopy</td></tr><tr><td>Colorado MicroDissection Needle</td><td>Stryker</td><td></td><td>Pointed electrocautery</td></tr><tr><td>Facial nerve monitoring</td><td></td><td></td><td></td></tr><tr><td>RobOtol</td><td>Collin</td><td></td><td>Robot dedicated to ear surgery</td></tr><tr><td>Space mouse</td><td>3DConnexion</td><td></td><td>RobOtol control arm</td></tr><tr><td>Standard otology surgical material</td><td></td><td></td><td>Including amongst standard instruments: speculum, Fisch dissectors</td></tr></tbody></table>

robot-assisted transcanal endoscopic ear surgery for congenital cholesteatoma

Congenital cholesteatoma accounts for 25% of cholesteatoma cases in children. Transcanal Endoscopic Ear Surgery (TEES) is ideal for these patients because it offers a wide endoscopic view of the middle ear and a minimally invasive approach. The two main limitations are the loss of one operative hand and a narrow external auditory canal in younger children. Here, we present the case of a 3-year-old patient with a Potsic stage III congenital cholesteatoma adherent to the incus and branches of the stapes. A robotic-assisted TEES procedure was performed, during which a robotic arm with 6 degrees of freedom held a 0&#176;, 2.9 mm wide endoscope, enabling the surgeon to work in a narrow environment with both hands. The procedure's duration was 2 h and 9 min, including 16 min for the installation and draping of the robotic arm. After a trans-canal approach, the cholesteatoma was dissected from the ossicles using both a needle (or sickle knife) and suction to stabilize the ossicles and limit the risk of hearing trauma. The cholesteatoma was debulked to reduce its size, allowing it to be pushed under the malleus anteriorly and then separated from other adherences before removal. A tragal cartilage graft was used to reinforce the tympanic membrane.

The case study reports a robotic-assisted total endoscopic ear surgery (TEES) for a Potsic stage III left congenital cholesteatoma in a 3-year-old child. The robotic arm was equipped with a 0&#176; and 30&#176;, 25 cm long, and 2.9 mm wide scope, connected to a 1080p full-HD camera and screen.
The pre-operative work-up revealed a typical congenital cholesteatoma with a CT scan showing a round anterior mass medial to the malleus, extending posteriorly between the stapedial crus and anteriorly into the supratubal recess (Figure 3). The ossicular chain remained intact. Audiometric testing indicated a slight 10 dB conductive hearing loss on the side of the lesion (Figure 4). The 3-year-old patient had a narrow external auditory canal, allowing only a size 3 speculum to be inserted. Therefore, the microscope was prepared as a backup, and the family was informed that an endaural approach might be necessary.
The installation of the robotic arm took 16 min, and the overall installation time (from intubation to incision, including all draping and instrument preparation) was 27 min. The total surgery duration (from intubation to closure) was 2 h and 9 min. The entire TEES was conducted with a 0&#176; endoscope, except for a 10 min interval when a 30&#176; scope was used to examine between the stapedial crus and the epitympanum. The microscope was not utilized.
A tragal graft was harvested through a direct incision and sutured before the endoscopic stage. The tympano-meatal flap was elevated from the malleus after a trans-canal approach, following which the congenital cholesteatoma (CC) was debulked, dissected from the incus and stapedial crus, and pushed forward under the malleus (Figure 5). It was then removed with an intact anterior and superior matrix. Due to the large size of the CC, a tragal graft was placed in an underlay fashion to prevent any future tympanic retraction before repositioning the tympano-meatal flap.
The procedure proceeded without surgical difficulties, particularly concerning the use of the robot. Passive movement of the endoscope could occur if it was pushed aside by an instrument, but this was gradual and did not obstruct the vision. Conversely, the instruments remained secure and stable throughout the procedure.
At the 6-week follow-up, the tympanic membrane and external auditory canal were healed without any epidermal inclusion cyst or myringitis. The 6-week post-operative audiometry indicated a slight conductive hearing loss, likely due to the use of underlay cartilage to reinforce the tympanic membrane. Importantly, there was no sensorineural hearing loss, which was the primary concern after extensive ossicular manipulation and dissection. The patient will undergo non-EPI diffusion-weighted MRI scans at 18 and 36 months after surgery, along with clinical and audiological follow-up for 8 to 10 years1.
<img alt="Figure 1" class="xfigimg" src="/files/ftp_upload/64861/64861fig01.jpg" /> 
Figure 1: Operating theatre setup for left tympanoplasty. In this proposed setup, the robot is positioned opposite the surgeon, aligned with the patient&#39;s external auditory canal axis. For a left tympanoplasty, the video tower is placed slightly to the left, towards the patient&#39;s feet. In the case of a right tympanoplasty, where the external auditory canal axis differs, the robot would be positioned towards the patient&#39;s feet. Please note that the surgical microscope should be draped and located in a corner of the room, though it&#39;s not depicted in the figure. <a href="https://www-jove-com.bdigitaluss.remotexs.co/files/ftp_upload/64861/64861fig01large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 2" class="xfigimg" src="/files/ftp_upload/64861/64861fig02.jpg" /> 
Figure 2: Peri-operative installation for left tympanoplasty. (A) The robot arm holder centralizes the endoscope to evenly distribute weight and minimize tube tension. (B) Observe the positioning of the video tower on the side opposite to the surgical field. The surgeon has a multi-directional control device, the space mouse, on the left for controlling the robotic endoscope holder. (C) The surgeon performs surgery on the left ear, facing the video tower, which is placed on the opposite side of the patient. (D) A close-up view from the surgeon&#39;s perspective shows the robotic arm holding the endoscope in line with the external auditory canal. Both surgical hands remain free for instrument manipulation and suction, akin to the conventional microscopic technique. The endoscope is capable of tilting, rotating, and translating at varying speeds using the space mouse. <a href="https://www-jove-com.bdigitaluss.remotexs.co/files/ftp_upload/64861/64861fig02large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 3" class="xfigimg" src="/files/ftp_upload/64861/64861fig03.jpg" /> 
Figure 3: Pre-operative CT-scan. The lesion is marked with an asterisk (*). (A) The transverse plane reveals an extensive congenital cholesteatoma involving the malleus and extending anteriorly into the supratubal recess. (B) In the transverse plane, the supratubal recess (&#167;) is clearly visible, along with the extension between the crus of the stapes, which appears intact (stage III congenital cholesteatoma). The retrotympanum (marked with &#164;) is devoid of any lesions. (C) The coronal plane displays a typical round mass medial to the malleus. (D) In the coronal plane, the extension of the lesion into the supratubal recess (&#167;) is shown anteriorly. <a href="https://www-jove-com.bdigitaluss.remotexs.co/files/ftp_upload/64861/64861fig03large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 4" class="xfigimg" src="/files/ftp_upload/64861/64861fig04.jpg" /> 
Figure 4: Audiometry (pre and post-operative). Left: Pre-operative audiometry reveals a slight 10 dB conductive hearing loss in the left ear, causing a minor asymmetry with the normal hearing in the right ear. Right: Six weeks post-operation, a 10 dB conductive hearing loss is observed in the left ear (likely due to the underlay cartilage graft), but notably, there is no sensorineural hearing loss. The x-axis represents hearing loss in decibels (dB), while the y-axis indicates frequencies in Hertz (Hz). <a href="https://www-jove-com.bdigitaluss.remotexs.co/files/ftp_upload/64861/64861fig04large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>
<img alt="Figure 5" class="xfigimg" src="/files/ftp_upload/64861/64861fig05.jpg" /> 
Figure 5: Endoscopic view (0&#176; endoscope). (A) This is an immediate pre-surgical view, where the anterior congenital cholesteatoma presses against the intact tympanic membrane. (B) The tympano-meatal flap has been elevated from the malleus, fully exposing the congenital cholesteatoma from the stapedial crus at the rear to the supratubal recess at the front. (C) After cholesteatoma removal, the ossicular chain remains intact. Note the broad scope of the 0&#176; endoscope view, spanning from the Eustachian tube at the front to the stapes at the rear. The black arrowhead in (A) and (B) points to the congenital cholesteatoma, which is removed in (C). <a href="https://www-jove-com.bdigitaluss.remotexs.co/files/ftp_upload/64861/64861fig05large.jpg" target="_blank">Please click here to view a larger version of this figure.</a>

Watch this Scientific Journal Video about Robot-Assisted Transcanal Endoscopic Ear Surgery for Congenital Cholesteatoma at JoVE.com

Robot-Assisted Transcanal Endoscopic Ear Surgery for Congenital Cholesteatoma

This protocol describes the removal of congenital cholesteatoma using minimally invasive transcanal endoscopic ear surgery with a two-handed approach and a robotic endoscope holder.

Congenital cholesteatoma accounts for 25% of cholesteatoma cases in children. Transcanal Endoscopic Ear Surgery (TEES) is ideal for these patients because ...

robot-assisted-transcanal-endoscopic-ear-surgery-for-congenital

Universidad San Sebastian

Research

JoVE Journal

Medicine

592 Views.  Université Paris Cité. This protocol describes the removal of congenital cholesteatoma using minimally invasive transcanal endoscopic ear surgery with a two-handed approach and a robotic endoscope holder.

Video: Robot-Assisted Transcanal Endoscopic Ear Surgery for Congenital Cholesteatoma

Implantation of Total Artificial Heart in Congenital Heart Disease

In patients with end-stage heart failure (HF), a total artificial heart (TAH) may be implanted as a bridge to cardiac transplant. However, in congenital heart disease (CHD), the malformed heart presents a challenge to TAH implantation. 
In the case presented here, a 17 year-old patient with congenital transposition of the great arteries (CCTGA) experienced progressively worsening HF due to his congenital condition. He was hospitalized multiple times and received an implantable cardioverter defibrillator (ICD). However, his condition soon deteriorated to end-stage HF with multisystem organ failure. 
Due to the patient's grave clinical condition and the presence of complex cardiac lesions, the decision was made to proceed with a TAH. The abnormal arrangement of the patient's ventricles and great arteries required modifications to the TAH during implantation.
With the TAH in place, the patient was able to return home and regain strength and physical well-being while awaiting a donor heart. He was successfully bridged to heart transplantation 5 months after receiving the device. This report highlights the TAH is feasible even in patients with structurally abnormal hearts, with technical modification.

This is a case report of a patient with congenitally corrected transposition of the great arteries (CCTGA) who received a total artificial heart (TAH) as a bridge to heart transplant. The TAH was successfully implanted with modifications to accommodate the patient's congenitally malformed heart.

In patients with end-stage heart failure (HF), a total artificial heart (TAH) may be implanted as a bridge to cardiac transplant. However, in congenital ...

Discovering Middle Ear Anatomy by Transcanal Endoscopic Ear Surgery: A Dissection Manual

The middle ear is located in the center of the temporal bone and bears a highly complex anatomy. The recently introduced exclusively endoscopic transcanal approach to the middle ear is a minimally invasive technique sparing the bone and mucosa of the mastoid bone, since the middle ear is accessed through the external auditory canal. This emerging method has several advantages over the traditional (microscopic) approaches to the middle ear such as the panoramic wide-angle views of the anatomy, the possibility to approach and magnify tiny structures, and the possibility of looking around the corner using angled endoscopes.
The cadaveric dissection method presented here consists of an overview on the technical requirements and a precise description of a step-by-step protocol to discover the anatomy of the middle ear. Each step and anatomical structure is carefully described in order to provide a comprehensive guide to endoscopic ear anatomy. In our opinion, this is particularly important to any novice in endoscopic ear surgery as it provides thorough anatomical knowledge and may improve surgical skills.

The aim of this article is to describe the methodology of exclusively endoscopic cadaveric middle ear dissection. Moreover, we aim to provide a comprehensive guide to endoscopic middle ear anatomy.

The middle ear is located in the center of the temporal bone and bears a highly complex anatomy. The recently introduced exclusively endoscopic transcanal ...

An Endoscopic Transcanal Transpromontorial Approach for Vestibular Schwannomas using a Computer-Based Three-Dimensional Imaging System

A 2D monocular endoscope has been used in transcanal transpromontory vestibular schwannoma surgery instead of craniotomy. However, the absence of depth perception is the limitation of this approach. With the loss of depth perception, the surgeon will be not able to perform delicate and particularly complicated surgery. A binocular endoscope has been developed to provide stereoscopic vision with better depth perception for complicated anatomic structures and has been applied in some endoscopic surgeries. However, the diameter of the endoscope is a limitation in the performance of transcanal otologic surgeries. A small diameter endoscope facilitates easier surgery in a restricted space. A computer-based 3D imaging system can obtain 3D images in real-time using a small monocular endoscope. In this study, to evaluate the feasibility of a computer-based 3D imaging system for endoscopic lateral skull base surgery, we applied this 3D imaging system in a transcanal transpromontorial approach in two patients with vestibular schwannomas. The surgical procedure was completed without complication in these two cases. There was no mortality, perioperative complications, nor notable postoperative complications. Using this computer-based 3D imaging system, a better depth perception and stereoscopic vision was observed compared to a conventional 2D endoscope. The improvement in depth perception offers superior management of the complicated surgical anatomy.

Here, we present a transcanal transpromontorial approach for vestibular schwannomas using a computer-based three-dimensional (3D) imaging system combined with a two-dimensional (2D) endoscope. This system provided stereoscopic vision, better depth perception and reduced visual fatigue. This 3D imaging system enabled the application of 3D vision technology in endoscopic lateral skull base surgery.

A 2D monocular endoscope has been used in transcanal transpromontory vestibular schwannoma surgery instead of craniotomy. However, the absence of depth ...

Endaural Endoscopic Atticoantrotomy (Retrograde Mastoidectomy) using a Constant Suction Bone-drilling Technique

Endoscopic middle ear surgery is a widely employed minimally invasive surgical technique to address middle ear and mastoid pathology. Bone drilling is the main technical challenge of endoscopic middle ear surgery. The accompanying video describes the detailed protocol of a constant-suction bone-drilling technique and the procedure of endaural exclusive endoscopic atticoantrotomy (retrograde mastoidectomy) using this technique. The main components of this bone-drilling technique include a soft and flexible suction tube, which is placed into the tympanic cavity to provide constant suction, and a soft sleeve, which is wrapped around the drill shaft to prevent the high-speed rotating shaft from damaging the lens of the endoscope. With these simple modifications, the traditional otological electrodrill can be used for drilling a tiny endaural incision in endoscopic middle ear surgery. Based on this bone-drilling technique, endaural endoscopic atticoantrotomy (retrograde mastoidectomy) can be successfully established for the removal of various amounts of bone, depending on the extent of the lesion. The short-term postoperative outcome seems promising.

Endaural Endoscopic Atticoantrotomy Retrograde Mastoidectomy using a Constant Suction Bone-drilling Technique

In this paper, we present the protocol and short-term outcomes of endaural exclusive endoscopic atticoantrotomy using a constant suction bone-drilling technique.

Endoscopic middle ear surgery is a widely employed minimally invasive surgical technique to address middle ear and mastoid pathology. Bone drilling is the ...

The Microscopic Transcanal Approach in Stapes Surgery Revisited

The microscopic transcanal (aka transmeatal) surgical approach was first described in the 60s, offering a minimally invasive means of reaching the external auditory canal, the middle ear, and epitympanon. Such an approach avoids a retroauricular or endaural skin incision; however, working through a narrow space needs angled microsurgical instruments and specific training in otologic surgery. The transcanal approach restricts the working space; however, it offers a binocular microscopic vision into the middle ear without extended skin incisions and thus, reducing post-operative pain and bleeding. In addition, this minimally invasive approach avoids scar tissue complications, hypoesthesia of the auricle, and potential protrusion of the pinna. Despite its numerous advantages, this method is still not routinely performed by otologic surgeons. Since this minimally invasive technique is more challenging, there is a need for extensive training in order for it to be widely adopted by otologic surgeons. This article provides step-by-step surgical instructions for stapes surgery and reports possible indications, pitfalls, and limitations using this microscopic transcanal technique.

This article describes the microscopic transcanal technique for stapes surgery, providing step-by-step surgical instructions for familiarizing surgeons with this approach.

The microscopic transcanal (aka transmeatal) surgical approach was first described in the 60s, offering a minimally invasive means of reaching the ...

Step-by-Step Stapedotomy through Transcanal Exclusive Endoscopic Approach

In recent years there has been an increasing trend in the use of the endoscope to treat a variety of middle ear pathologies, including otosclerosis. Several studies comparing traditional microscopic and endoscopic stapes surgery have reported similar hearing results and an overall low rate of complications. The endoscope has unraveled its full potential in demanding settings of stapes surgery, such as unfavorable anatomy of the oval window niche or revision cases. Reduced manipulation of the chorda tympani and low rate of post-operative dysgeusia are further benefits to mention for endoscopic stapes surgery.
Being a one-handed technique, management of bleeding, positioning, and crimping of the prosthesis may be challenging for novice endoscopic surgeons, so some training in endoscopic ear surgery is recommended before performing endoscopic stapedotomy. The problem of sharing the surgical field between the endoscope and the operating instruments could be easily overcome if proper instruments positioning is understood. One-handed bleeding control in the narrow space of the ear canal may represent an issue during the elevation of the tympano-meatal flap, possibly discouraging the surgeon since the preliminary steps of surgery. Following appropriate technique to raise the flap and the collaboration with the anesthesiology team in keeping the blood pressure low guarantee an adequate bleeding control in most cases.
The aim of this article is to describe the entire surgical procedure of a transcanal exclusive endoscopic stapedotomy, from operating room set up and patient positioning to post-operative care. A step-by-step description of the surgical maneuvers with technical hints is reported, to guide the surgeon across the procedure and allow any ear surgeon to perform stapes surgery endoscopically.

The aim of this article is to provide a step-by-step method for endoscopic stapes surgery from operating room setting and patient positioning to post-operative care. This work would represent a guide for any otologic surgeon who is willing to treat otosclerosis with endoscopic transcanal technique.

In recent years there has been an increasing trend in the use of the endoscope to treat a variety of middle ear pathologies, including otosclerosis. ...

Endoscopic Cholesteatoma Surgery

Implementation of endoscopes in cholesteatoma surgery resulted in considerable changes in the management of cholesteatoma in the last two decades. Compared to the microscopic approach with an excellent but straight-line view and limited illumination, the introduction of endoscopes provides a wide-angled panoramic view. Moreover, angled lenses allow the surgeon to visualize the middle ear and its hidden recesses through a transcanal, minimally-invasive approach. The endoscope enables the surgeon to remove limited cholesteatoma of the middle ear and its recesses using an exclusive endoscopic technique by taking advantage of these benefits. This reduces the rate of residual disease and sparing external incisions and excessive temporal bone drilling as in a transmastoid approach. Since transcanal endoscopic access is mainly a one-handed technique, it implies the need for specific procedures and technical refinements. This article describes a step-by-step guide as a surgical manual for endoscopic removal of epitympanic cholesteatoma. Different techniques for cholesteatoma dissection and bone removal for epitympanectomy, including curettage and powered instruments such as drills and ultrasonic devices with their outcomes, are discussed. This may offer ear surgeons insight into technical refinements and the latest technological developments and open the horizon for different techniques.

The present protocol describes a step-by-step guide for the complete endoscopic removal of epitympanic cholesteatoma with different techniques for cholesteatoma dissection and bone removal for epitympanectomy.

Implementation of endoscopes in cholesteatoma surgery resulted in considerable changes in the management of cholesteatoma in the last two decades. ...

Robotic Cochlear Implantation for Direct Cochlear Access

Robot-assisted systems offer great potential for gentler and more precise cochlear implantation. In this article, we provide a comprehensive overview of the clinical workflow for robotic cochlear implantation using a robotic system specifically developed for a minimally invasive, direct cochlear access. The clinical workflow involves experts from various disciplines and requires training to ensure a smooth and safe procedure. The protocol briefly summarizes the history of robotic cochlear implantation. The clinical sequence is explained in detail, beginning with the assessment of patient eligibility and covering surgical preparation, preoperative planning with the special planning software, drilling of the middle ear access, intraoperative imaging to confirm the trajectory, milling of the inner ear access, insertion of the electrode array, and implant management. The steps that require special attention are discussed. As an example, the postoperative outcome of robotic cochlear implantation in a patient with advanced otosclerosis is presented. Finally, the procedure is discussed in the context of the authors' experience.

Robotic cochlear implantation is a procedure for minimally invasive inner ear access. Compared to conventional surgery, robotic cochlear implantation involves additional steps that need to be carried out in the operating room. In this article we give a description of the procedure and highlight the important aspects of robotic cochlear implantation.

Robot-assisted systems offer great potential for gentler and more precise cochlear implantation. In this article, we provide a comprehensive overview of ...

Surgical Treatment of an Endolymphatic Sac Tumor

Endolymphatic sac tumors (ELST) are low-grade papillary adenocarcinoma originating from the endolymphatic sac. Usually slow-growing, with local aggressiveness and a low risk of distant metastases, ELST can be sporadic but also frequently associated with von Hippel Lindau disease. The current treatment of ELST is primarily surgical resection. A 55-year-old woman accessed our otologic tertiary level referral center for a sudden worsening of hearing loss in her left ear and vertigo. A magnetic resonance (MRI) and computer tomography scan study subsequently showed a mass in the petrous bone; hence, the presence of an ELST was hypothesized. After embolization of the mass, the patient underwent surgical removal of the lesion. The resection of the mass was done through a translabirinthine approach, with an uneventful procedure. No residual disease remained after surgery. After 24 months of radiologic follow up with MRI, there are no signs of recurrence disease. This paper reports the management of this sporadic ELST, as well as the follow up results, providing clinicians this protocol for the handling of such a challenging otologic skull base surgery and rare disease.

Here, we discuss clinical and radiological features of endolymphatic sac tumors and report the methodology and results of a surgical removal in a case in care at our otologic referral center.

Endolymphatic sac tumors (ELST) are low-grade papillary adenocarcinoma originating from the endolymphatic sac. Usually slow-growing, with local ...

A Comprehensive Step-By-Step Guide for Exclusive Endoscopic Ossiculoplasty

Techniques of Endoscopic Ossiculoplasty

The utilization of endoscopes in modern otology has evolved from diagnostic purposes to the development of exclusive endoscopic ear surgery. This technique offers a panoramic view of the middle ear and provides an optimal magnification of the oval window region, the stapes' suprastructure, and the footplate, allowing great precision in prosthesis positioning during ossiculoplasty (OPL). Various techniques for ossicular chain reconstruction have been described in the literature. Either autologous or synthetic materials can be used for reconstruction. The use of a patient's own tissue minimizes the risk of implant rejection or extrusion of the prosthesis through the tympanic membrane. On the other hand, synthetic materials like titanium are light and rigid and do not require time-consuming prosthesis remodeling. The main objective of this article is to present a comprehensive step-by-step guide that serves as a surgical manual for exclusive endoscopic OPL. This guide will explain various forms of OPL using synthetic and autologous materials. The goal is to provide a comprehensive understanding of the various surgical techniques and support the integration into clinical practice.

Author Spotlight: Advancing Endoscopic Ossiculoplasty &#8211; Techniques, Innovations, and Practical Guidance for Clinical Integration

Exclusive Endoscopic ossiculoplasty (EEO) is a promising and minimally invasive approach for the treatment of conductive hearing loss due to ossicular chain disruptions and associated middle ear pathologies. Herein, step-by-step instructions and a discussion of various endoscopic ossiculoplasty techniques are presented.