Endoscopic Transclival Approach Research Articles

The endoscopic transcanal approach to the internal auditory canal: an anatomic study.

The internal auditory canal (IAC) plays a key role in lateral skull base surgery. Although several approaches to the IAC have been proposed, endoscope-assisted transcanal corridors to the IAC have rarely been studied. We sought to provide a step-by-step description of the transcanal transpromontorial approach to the IAC and analyze anatomic relationships that might enhance predictability and safety of this approach. Ten cadaveric specimens were dissected and the extended transcanal transpromontorial approach to the IAC was established. Various morphometric measurements and anatomic landmarks were reviewed and analyzed. The proposed technique proved feasible and safe in all specimens. There was no inadvertent injury to the jugular bulb or internal carotid artery. The chorda tympani, a key landmark for the mastoid segment of the facial nerve, was identified in all dissections. The spherical recess of the vestibule and middle turn of cochlea are important landmarks for identification of the labyrinthine segment of the facial nerve. Identification of all boundaries of the working area is also essential for safe access. Among various morphometric measurements, the modiolus-IAC angle (≈150°) proved particularly consistent; given its ease of use and low variability, we believe it could serve as a landmark for identification and subsequent dissection of the IAC. The extended transcanal transpromontorial approach to the IAC is feasible and safe. Relying on anatomic landmarks to ensure preservation of the involved neurovascular structures is essential for a successful approach. The modiolus-IAC angle is a consistent, reproducible landmark for IAC identification and dissection.

Detailed Radiomorphometric Analysis of the Surgical Corridor for the Suprageniculate Approach.

The suprageniculate fossa (SGF) is located between the geniculate ganglion, the middle cranial fossa (MCF) and the anterior semicircular canal (ASCC). An endoscopic transcanal approach has been recently proposed to treat the different lesions in this area. The aim of the study is to describe the anatomical pathway of this approach by measuring the dimensions of its boundaries while checking their correlation with the pneumatization of the SGF area. This is a retrospective anatomical analysis of Cone Beam CT scans of 80 patients, for a total of 160 temporal bones analyzed. Two checkpoints were measured for the SGF route, as an internal and an external window. These are triangles between the MCF dura, the geniculate ganglion and the ASCC on parasagittal and axial planes. The pneumatization of the SGF was also assessed, classified and correlated with the measured dimensions. The depth of the SGF was 7.5 ± 1.8 mm. The width of the external window was 7.5 ± 1.9, 5.6 ± 2.4 and 1.6 ± 1.6 mm for the posterior, middle and anterior points of measurement, respectively. The height of the internal window was 7.6 ± 1.2, 4.5 ± 1.5 and 1.7 ± 1.7 mm for the posterior, middle and anterior points of measurement, respectively. Type A pneumatization was found in 87 cases, type B in 34 and type C in 39. The degree of pneumatization directly correlated to the depth and height of the fossa. The suprageniculate approach route is defined by the internal and external windows which should be evaluated during a pre-surgery imaging assessment. The detailed anatomy of the approach and the novel classification of the pneumatization of the SGF are here described which may be useful to plan a safer procedure with minimal complications.

Exclusive endoscopic management of incus long process major defects: conventional incus interposition versus malleostapediopexy.

The aim of the current study is to compare the surgical and audiometric results of conventional incus interposition (IP) versus malleostapediopexy (MS) in incus long process large defects. A total of 71 patients (incus IP group n = 37, MS group n = 34) were enrolled in this study. All patients enrolled in the current study underwent ossiculoplasty via an exclusive endoscopic transcanal approach. Pre- and postoperative audiometric measurements and air-bone gap (ABG) values were compared, and if the postoperative ABG value was less than 20dB, ossiculoplasty was considered successful. Graft success rates and complications were also compared. The average auditory gain was 14.7 ± 4.2dB in the incus IP group and 18.3 ± 5.1dB in the MS group. The auditory gain was significantly greater in the MS group relative to the incus IP group (p = 0.012). Ossiculoplasty success (postoperative ABG value < 20dB) rate was 70.3% in the incus IP group patients and 88.2% in the MS group patients (p < 0.001). There was no significant difference in terms of graft success rate between groups (p > 0.05) and the overall graft uptake rate was 91.5% (65/71). Malleostapediopexy-bridging of malleus and stapes using bone cement-is an effective, reasonable, and more efficient technique in terms of auditory outcomes relative to the conventional incus interposition in endoscopic transcanal management of incus long process major defects.

Blue laser for the exclusive endoscopic transcanal approach to middle ear paraganglioma

BackgroundThe management of glomus tympanicum tumours can be challenging. Blue laser coagulation may improve bleeding control thus facilitating an endoscopic transcanal excision. The objective of this presentation is to illustrate the authors’ experience using this novel tool.MethodsCase report of a patient that underwent exclusive endoscopic transcanal blue laser surgery of a class A2 glomus tympanicum tumour in a tertiary referral center.ConclusionThe present study provides evidence of the safety and efficacy of endoscopic blue laser surgery, for the minimally invasive treatment of early-stage glomus tympanicum tumours.

Transcanal Endoscopic Facial Nerve Decompression in Posttraumatic Facial Paralysis: A Tertiary Care Experience

Purpose: Facial nerve decompression (FND) for traumatic facial palsy with lesion at geniculate ganglion and tympanic segment can be done through transcanal approach, by a microscope or an endoscope without opening the mastoid. The study analyzes the outcomes of transcanal endoscopic approach (TEA) for FND with regard to improvement in facial nerve (FN) function and hearing status, in lesions limited to perigeniculate and tympanic segment of FN. Methodology: This was a retrospective analysis of the case series from a tertiary care center, of the patients with posttraumatic FN paralysis, surgically treated with TEA. From January 2014 to December 2018, nine patients of traumatic facial palsy were selected for surgery. The patients posted for surgery were selected only when they had immediate-onset FN paralysis after trauma and not responding to treatment of systemic corticosteroid for 14 days with, House Brackmann grading (HBG) IV–VI, lesions confined to perigeniculate ganglion and tympanic segment of FN. Outcome analysis following TEA for FND was performed in terms of postoperative FN function and hearing improvement. Results: The TEA showed a postoperative improvement of FN function (HBG I/II) in 77.7% of patients within 6-month follow-up period. There was no significant improvement in FN function between 6th and 12th month. Postoperative hearing improvement was seen in eight cases, and there was no improvement in one case due to preoperative sensorineural hearing loss. Conclusion: TEA for FND is a direct approach for lesions confined to perigeniculate ganglion area and tympanic segment without involvement of mastoid segment of FN. It requires minimal bone drilling, provides proper visualization, and accurate surgical site assessment. Surgeries performed even in late presentations may have favorable outcomes.

Glomus tympanicum removal using transcanal endoscopic assisted surgery: An experience with six cases.

To evaluate an endoscopic approach in the management of glomus tumor, and also to investigate and evaluate its appropriateness and feasibility. Glomus tumors, also known as paragangliomas, are benign primary tumors of the middle ear. The advent of endoscopic ear surgery has provided new dimensions to the management of this highly vascular tumor. Retrospective analysis of six patients of glomus tympanicum, operated between July 2014 and June 2019, with modified Fisch classification Type A and B1, who were managed by a retroauricular transcanal endoscopic approach. Preoperative and postoperative analysis was done for these patients. The chief complaint was pulsatile tinnitus, which disappeared in five cases and reduced in severity in one of them. Hearing was improved with reduction in air-bone gap in all the cases. No major complications or recurrence were observed in any of the patients after 12 months of follow-up. This endoscopic approach serves as a safe and reliable technique for tumor removal. It thus provides postoperative comfort for most of the patients.

Accuracy of High-Resolution Computed Tomography Compared to High-Definition Ear Endoscopy to Assess Cholesteatoma Extension.

To correlate radiographic evidence of cholesteatoma in the retrotympanum with intraoperative endoscopic findings in cholesteatoma patients and to evaluate the clinical relevance of radiographic evidence of cholesteatoma in the retrotympanum. Case series with chart review. Tertiary referral center. Seventy-six consecutive cases undergoing surgical cholesteatoma removal with preoperative high-resolution computed tomography (HRCT) were enrolled in this study. A retrospective analysis of the medical records was conducted. The extension of cholesteatoma regarding different middle ear subspaces, into the antrum and mastoid were reviewed radiologically in preoperative HRCT and endoscopically from surgical videos. Additionally, facial nerve canal dehiscence, infiltration of the middle cranial fossa, and inner ear involvement were documented. Comparison of radiological and endoscopic cholesteatoma extension revealed statistically highly significant overestimation of radiological cholesteatoma extension for all retrotympanic regions (sinus tympani 61.8% vs19.7%, facial recess 69.7% vs43.4%, subtympanic sinus 59.2% vs7.9%, and posterior sinus 72.4% vs4.0%) and statistically significant overestimation for mesotympanum (82.9% vs56.6%), hypotympanum (39.5% vs9.2%), and protympanum (23.7% vs6.6%). No statistically significant differences were found for epitympanum (98.7% vs90.8%), antrum (64.5% vs52.6%), and mastoid (26.3% vs32.9%). Statistically significant radiological overestimation of facial nerve canal dehiscence (54.0% vs25.0%) and invasion of tegmen tympani (39.5% vs19.7%) is reported. Radiologic cholesteatoma extension in different middle ear subspaces is overestimated compared to the intraoperative extension. The preoperative relevance of radiological retrotympanic extension might be limited in the choice of approach and transcanal endoscopic approach is always recommended first.

Management of a Posterior Mesotympanic Cholesteatoma using the Transcanal Endoscopic Approach

With the constant evolution in the role of endoscopy in middle ear surgery, this article presents a technical note on the transcanal endoscopic approach to resection of a cholesteatoma limited to the posterior mesotympanum. We believe that this technique provides a suitable, minimal-invasive alternative to the classic microscopic transmastoid approach.

Indications of and Efficacy of Facial Nerve Decompression Through Endoscopic Transcanal Approach for Patients with Traumatic Facial Paralysis.

The aim of this study is to evaluate the indications and efficacy of facial nerve decompression through an endoscopic transcanal approach for patients with traumatic facial paralysis. This single-center retrospective study included 11 patients with traumatic facial paralysis from February 2018 to April 2019. We compared the facial nerve and auditory function before and after operation so as to reveal the feasibility and effect of the surgical approach. All 11 patients have successfully received facial nerve decompression through endoscopic transcanal approach. Facial nerve function was objectively evaluated by electroneurography test and House-Brackmann facial nerve grading system. All patients were graded HB-VI with electroneurography ≥ 95% before surgery. The recovery of facial nerve function was good (HB-I or II) (90.9%) a year after surgery with only one case (9.1%) for HB-III. Preoperative high-resolution computed tomography showed that 1 patient had ossicular chain interruption, which was confirmed during operation. Meanwhile, 2 patients with air-bone gap >35 dBHL and whose computed tomography failed to diagnose were found with ossicular chain interruption during operation. The air-bone gap of patients with normal ossicular chain connection was all <30 dBHL. The average air-bone gap was reduced from 27.5 ± 10.1 dBHL to 7.8 ± 3.3 dBHL after operation. Preoperative high-resolution computed tomography combined with localization test can accurately estimate the location of facial nerve injury. Facial nerve decompression through endoscopic transcanal approach can decompress the geniculate ganglion to pyramidal segment of facial nerve, which is suitable for patients with traumatic facial paralysis of this segment. In addition, air-bone gap >35 dBHL may indicate the ossicular chain interruption when it is difficult to be completely judged by high-resolution computed tomography.

Inside-Out Transcanal Endoscopic Mastoidectomy: Literature Revision.

Introduction Recently, there have been significant advancements in transcanal endoscopic ear surgery (TEES). The combination of rigid and thin otoendoscopes with high-definition cameras enabled a less invasive transcanal access to the middle ear and a clearer view of the surgical field. Several surgeons have recently published studies about cholesteatoma resection via transcanal endoscopic surgery, even in cases where the disease has extended to the mastoid, requiring transcanal endoscopic mastoidectomy. Objectives To analyze the currently available literature on transcanal endoscopic inside-out mastoidectomy, and to determine its efficacy as a surgical technique by evaluating the disease's relapse/recurrence rate. Data Synthesis Initially, the titles and abstracts of articles identified were analyzed. At this stage, 117 articles were analyzed, 97 of which were excluded for not meeting the inclusion criteria. The 20 remaining articles were further evaluated. The articles were classified on the basis of five levels of scientific evidence. Final Comments The analysis of the studies showed that the transcanal endoscopic approach is effective in providing access to the attic or antrum, especially in cases of sclerotic mastoids. There was only one study with grade A recommendation, which showed the efficacy of endoscopic ear surgery in the treatment of cholesteatoma. Furthermore, there were three studies with grade B recommendation, showing less relapse/recurrence after TEES. More studies with grade A and B recommendations are needed to better evaluate the effectiveness of TEES, especially compared with that of traditional microscopic surgery.

Endoscopic endonasal transclival approach for a ventral brainstem epidermoid cyst: illustrative case.

Intracranial epidermoid cysts are benign, slow-growing malformations that most commonly arise at the skull base. Maximizing resection of the cyst contents and the capsule reduces long-term recurrence but can be made difficult by cyst wall adherence to critical neurovascular structures. Expanded endonasal approaches (EEAs) offer an alternative to traditional open transcranial approaches for accessible epidermoid cysts. In this case report, the authors demonstrate a transclival EEA for a large, ventral brainstem epidermoid cyst. A 41-year-old woman who presented with progressive headaches, diplopia, malaise, and fatigue was found to have a 4.7-cm midline, ventral brainstem epidermoid cyst. She underwent an expanded endonasal transclival approach that exposed the brainstem from the level of the dorsum sella to the tip of the basion. A near-total resection was completed with removal of all cyst contents and most of the capsular wall. Reconstruction was completed with Duragen, an autologous fat graft, and a nasoseptal flap. Postoperatively, she had a partial left cranial nerve VI palsy that remained stable 8 weeks after surgery. The expanded endoscopic transclival approach can facilitate effective resection of midline, ventral epidermoid cysts.

Transcanal Endoscopic Stapedial and Tensor Tympani Tenotomy for Middle Ear Myoclonus: A Retrospective Case Series of Surgical Outcomes.

To describe and analyze the surgical outcomes of transcanal endoscopic resection of the stapedial tendon (ST) and tensor tympani tendon (TT) in the management of middle ear myoclonus (MEM). A retrospective case series. Tertiary academic center. Seven consecutive patients (seven ears) with tinnitus were diagnosed with MEM. Transcanal endoscopic resection of both the ST and TT using either microinstruments or a laser. The symptom of tinnitus, based on visual analog scale and Tinnitus Handicap Inventory scores, was analyzed preoperatively and postoperatively for each patient. The intraoperative findings and postoperative complications were also evaluated. Amelioration of objective tinnitus with significant improvement in visual analog scale and Tinnitus Handicap Inventory scores was noted in all seven patients. The ST and TT were easily identified in the same endoscopic field, with minimal or no removal of the scutum. There was no need to perform an anterior tympanotomy to expose the TT. Resection of both the ST and TT and creating a gap between the cut edges were achieved by using either microinstruments or a laser under an endoscopic field. Conversion to or conjunction with the microscopic approach was unnecessary for any of the seven patients. No hearing loss or hyperacusis occurred postoperatively. Transcanal endoscopic resection of the ST and TT successfully ameliorated the symptom of tinnitus in patients with MEM. A transcanal endoscopic approach provides an alternative method to manage MEM, providing excellent visualization and minimal invasiveness.

Endaural microscopic approach versus endoscopic transcanal approach in treatment of attic cholesteatomas

PurposeCompare the audiological results and postoperative outcomes of the endoscopic approach versus the endaural microscopic approach for treatment of attic cholesteatomas, using a randomized prospective model. Materials and methodsEighty patients were consecutively enrolled in the study and randomized into two groups of treatment of 40 patients: Group A –tympanoplasty with a microscopic endaural approach; Group B –tympanoplasty with an exclusive trans-meatal endoscopic approach. Preoperative, intraoperative and postoperative outcomes were evaluated. Hearing was assessed preoperatively and at 1 month, 3 months and 6 months after surgery in both groups. ResultsThere were no differences in the parameters analyzed (CT findings, patient age, disease duration, intraoperative cholesteatoma characteristics,) between the group A and B patients. No statistical difference between the two groups regarding hearing improvement, abnormal taste sensation, dizziness, post-operative pain and healing times emerged. Graft success rate was 94.5 % and 92.1 % for MES and ESS respectively. ConclusionBoth microscopic and exclusively endoscopic endaural approaches offer similar and excellent results in the surgical treatment of attic cholesteatomas.

Transcanal endoscopic type 3 tympanoplasty with mastoid preservation for advanced active chronic mucosal otitis media

Background Chronic mucosal otitis media is a very common ear disease for which patients attend otolaryngology clinics. Most of these patients present with actively discharging ears. Aims/Objectives This study aims to observe the middle ear space pathology and obtain surgical outcomes as a treatment for patients with advanced chronic mucosal otitis media with a transcanal endoscopic ear surgery approach. Materials and methods: A prospective study was designed, and patients suffering from chronic mucosal otitis media in the active suppurative phase with an air-bone gap larger than 20 dB were included. Results 70 operated ears were included. Underlying macroscopic pathology within the middle ear space was observed: Middle ear granulomas at 58.6%; Tympanosclerosis 41.4%. Blockage of the tympanic isthmus was evaluated, obtaining a blockage rate of 81.4%. At 12 months of evaluation after surgery, a postoperative ABG < 20 dB was achieved in 85.7% of the operated ears. An overall closed tympanic membrane was obtained in 88.6% of the patients. Conclusion This prospective cohort study shows the short-term efficacy of transcanal endoscopic type 3 tympanoplasty with mastoid preservation for managing advanced chronic mucosal otitis media. Clinical trials are required to give more evidence to the present matter.

A novel technique in treatment of advanced tympanosclerosis: results of malleus replacement and loop prostheses combination; pure endoscopic transcanal approach.

The objectives of the present clinical trial are to describe our surgical technique for advanced tympanosclerosis (TS) and to present the comparison of pre-and postoperative audiometric results. 21 patients suffering from advanced TS (Only type III and IV patients according to Wielinga-Kerr classification) were enrolled in this prospective study. A pure transcanal endoscopic approach was preferred for all patients included in the study. Titanium malleus replacement prosthesis (MRP) and polytetrafluoroethylene (PTFE) loop prosthesis combination were used to bypass fixed ossicles to achieve sound transmission to the inner ear. Pre-and postoperative pure tone audiometry (PTA) measurements and air-bone gap (ABG) results compared, and surgical technique was considered successful if postoperative ABG was less than 20dB. Six of the 21 patients had been operated on before and the tympanic membrane (TM) was intact. The remaining 15 of the 21 patients were the primary cases, and TM perforation repair and ossiculoplasty using combination of the MRP and PTFE loop prosthesis were performed at single-staged operation. The average preoperative ABG values significantly improved from 37.1 ± 6.2 to 14.5 ± 1.2dB postoperatively (p < 0.001). The mean preoperative air conduction threshold (ACT) significantly decreased from 51.7 ± 11.4 to 28.5 ± 9.1dB (p < 0.001). TS surgery is still a controversial issue particularly in stapes footplate fixation. However, our surgical and audiological results in this study are quite promising. The combination of titanium MRP and PTFE loop prosthesis for restoring sound transmission in advanced TS cases is reliable, effective and novel treatment option via endoscopic transcanal approach.

Outcomes of transcanal endoscopic middle ear surgery for congenital cholesteatoma

Background Transcanal endoscopic surgery offers advantages for congenital cholesteatoma (CC) which is expanding cystic mass located on an intact tympanic membrane. Objectives To determine the efficacy of transcanal endoscopic ear surgery for the treatment of CC. Material and methods Eleven patients with CC confined to the middle ear underwent transcanal endoscopic ear surgery by surgeons who were skilled in otoscopic surgery. According to the Potsic classification, four, three, and four patients had lesions in stages 1, 2, and 3, respectively. The mean follow-up duration was 24.5 months. We retrospectively analyzed the recurrence rate, complications, and average hearing thresholds of the patients with CC. Results All CCs were successfully resected via the transcanal endoscopic approach, without any immediate or serious complications. The only complication was external auditory canal stenosis due to postoperative scarring, which occurred in a patient with a stage-3 cholesteatoma that recurred and required reoperation and second-stage ossicular chain reconstruction. Two more patients underwent one-stage ossicular chain reconstruction. All three patients received a total artificial ossicular replacement prosthesis, and two of them also received cartilage grafts. Conclusions and significance Transcanal endoscopic ear surgery is an effective method to treat CC belonging to Potsic stages 3 or below.

Surgical methods of cerebrospinal fluid otorhinorrhea due to inner ear malformation in children

Objective:To discuss the application of two surgical methods, trans-mastoid approach and trans-canal endoscopic approach, in the treatment of CerebroSpinal Fluid（CSF） otorhinorrhea due to inner ear malformation（IEM） in children. Methods:Children with CSF otorhinorrhea due to IEM, from July 2015 to Jan 2021, in ENT department, Beijing Children's Hospital were retrospectively analyzed, and the clinical data, surgical methods, complications, recurrence and follow-up were recorded. Results:30 children with CSF otorhinorrhea due to IEM were included. Half of them had a history of otorhinorrhea, and 53.3% of them were diagnosed as cerebrospinal fluid（CSF） otorrhea at the first onset Unilateral and bilateral IEM were 22 cases and 8 cases respectively. All unilateral IEM children had secondary infections such as meningitis or/and pneumonia, and 9.1% had cochlear implantation（CI） due to deafness after meningitis. 87.5% bilateral IEM children had CI due to profound/severe hearing loss. 96.7% CSF otorhinorrhea were unilateral, there was no relationship between CSF otorhinorrhea and the malformation side or the time of CI surgery. Trans-mastoid approach was used in 14 cases, usually involving CI or other operations; and endoscopic approach in 16 cases. The age of trans-mastoid group was younger than that of endoscopic group. No recurrence and complications occured in the trans-mastoid group. In the endoscopic group, 2 cases recurred; 3 cases had complications（2 with temporary facial paralysis and 1 with labyrinth and intracranial pneumatosis）. Except one case lost, the others were followed up for 1.2-6.7 years, and no recurrence of pneumonia, meningitis and CSF otorhinorrhea happened. Conclusion:Unilateral IEM usually leads to meningitis or/and pneumonia, and bilateral IEM requires CI. Both trans-mastoid and trans-canal endoscopic approach were effective for CSF otorrhea repair. Trans-mastoid approach is suitable for those who need mastoid exploration, CI or combined with other operations. Trans-canal endoscopic approach was choosed when fistula was confined to the tympanum and ear canal diameter was wide enough.

Nuances in transcanal endoscopic approach to benign middle ear tumours in adult patients

Background and objectiveMinimally invasive surgery of benign middle ear tumours is possible by using the endoscope. The optimal lighting and the broadest vision it offers, allow a transcanal approach to these rare tumours. The objective of this work is to summarise its key points through a case series. Materials and methodsRetrospective study of benign middle ear tumours that underwent exclusive endoscopic surgery in a third-level adult university hospital between June 2018 and June 2020. Postoperative follow-up was performed by otoendoscopy and audiometry. ResultsSix patients underwent surgery during the study period. Five patients were female and one male, with an average age of 57.8 years (±21.9). Four tumours were in the left ear and 2 in the right ear. These included four tympanic paragangliomas (three type I and one type II), a chorda tympani neuroma, and a congenital cholesteatoma. There were no serious postoperative complications. At present, no tumour recurrence has been found in either case, with a minimum follow-up of 7 months. ConclusionsThe present study adds evidence on the safety and efficacy of endoscopic transcanal ear surgery, as a minimally invasive technique, for the treatment of benign middle ear tumours confined to the tympanic cavity.

Endoscopic closure of tympanic membrane anterior perforation using a strip-type chondroperichondrial graft.

Myringoplasty is a surgical procedure to reconstruct tympanic perforation. However, repair of anterior perforations is still challenging. To analyze the anatomical and hearing outcomes of myringoplasty with a new technique of chondroperichondrial graft via endoscopy, 23 adult patients were retrospectively analyzed. All patients had anterior perforations of tympanic membranes that were repaired with a composite strip-type cartilage-perichondrium graft through a total endoscopic transcanal approach. The anatomical graft success rate at postoperative 1 month was 86.96% (20/23) and reached 100% at the 6- and 12-month follow-up. Compared to the preoperative air conduction threshold (44.7 ± 13.56 dB) and air-bone gap (ABG) (22.35 ± 6.54 dB), the postoperative air conduction threshold and ABG decreased to 33.52 ± 10.88 dB and 12.52 ± 3.94 dB, respectively (P < .0001). Twenty-two (95.65%) patients had an ABG below 20 dB postoperatively. The mean ABG improvement in our cohort was 9.83 ± 5.00 dB. The functional graft success rate was 95.65% (22/23). The convenience, reliability, time, and labor savings accrued from the approach described here make it a good choice for repair of anterior perforation of tympanic membrane.

Canalplasty using underwater bone drilling in transcanal endoscopic myringoplasty for patients with a narrow external auditory canal

Background Canalplasty is important in microscopic ear surgery, but it has rarely been studied in otoendoscopic surgery. Objectives The aim of this study was to investigate the application of canalplasty due to external auditory canal stenosis caused by bony bulges in endoscopic myringoplasty. Materials and methods The procedures and effects of canalplasties and myringoplasties were analysed. During the canalplasties, depending on the location of the bulges, the meatal skin flaps were elevated in different manners, and the underwater bone drilling technique was adopted to remove the bulges to enlarge the osseous canals. Results Canalplasties were performed in 18.5% (33/178) of myringoplasties. All surgeries were completed exclusively via the transcanal endoscopic approach. No iatrogenic injuries were found. Most of the canalplasties required drilling off bulges on multiple walls. The mean total duration of the canalplasties and myringoplasties was 76.6 ± 4.5 min, and the proportion of time required for the canalplasties was 47.3 ± 2.4%. Conclusion Only approximately one in five endoscopic myringoplasties require antecedent canalplasties due to concurrent canal stenosis. With the underwater bone drilling technique, transcanal endoscopic canalplasty can be safely and efficiently conducted.