The Current Limitations and Future Direction of Instrument Design for Totally Endoscopic Ear Surgery: a Needs Analysis Survey

[Experiences with endoscopic ear surgery of a German tertiary hospital for otolaryngology]

BACKGROUND

The aim of this article is to report on the integration of endoscopic ear surgery (EES) into daily clinical practice.

MATERIAL AND METHODS

In a monocentric prospective study, the endoscopy unit was set up during even weeks over a period of 10 months and the procedure was primarily started endoscopically via a transmeatal approach. In odd weeks, the endoscopy was omitted. A total of 60 procedures in 59 patients were evaluated. Points of comparison were intraoperative vision, incision-suture time, postoperative hearing outcome, and postoperative otoscopic findings.

RESULTS

With the exception of the facial nerve (p = 0.15 Mann-Whitney U‑test), the EES showed significantly improved visualization of all areas in the middle ear. The incision-suture times were similar in both methods. If bimanual placement of an ossicular prosthesis was necessary, the incision-suture time increased disproportionately (MES: 57.18 ± 9.7 min, EES: 76.83 ± 24.99 min; p = 0.019, *). There were no statistically significant changes related to hearing outcomes when comparing EES with the microscopic technique. There were no postoperative complications in the EES surgery group.

CONCLUSION

Integration of EES proved to be successful and advantageous in a real patient collective at this location.

A Novel Instrument for Endoscopic Ear Surgery With a Steerable Flexible Tip: A Pediatric Anatomical Validation Study

HYPOTHESIS

This study compares the reaching ability of two classes of transcanal endoscopic ear surgery (TEES) instruments when operating on difficult to access anatomical targets; two novel instruments with steerable flexible tips (SFT-A and SFT-B) and suction capability are compared with standard commercially available tools.

BACKGROUND

TEES surgeons identified the need for a new surgical instrument that can enable accessibility of all areas visualized by the endoscope. This motivated the development of the two instrument prototypes.

METHODS

Six temporal bone models were 3D printed based on CT data from five cholesteatoma patients. Four anatomical targets were marked on each model. Using these targets, the reaching ability while using four standard TEES instruments were compared with the SFT-A and SFT-B prototypes by five surgeon participants. Results were analysed to compare success rates of contacting each target using each tool by fitting four Firth's logistic regression models. This calculated the statistically significant differences (p < 0.05) in tool success rate.

RESULTS

Using SFT-A to contact the sinus tympani (100%) was significantly more successful than the Panetti suction dissector for atticus (PAT) (77%) and to contact the sinodural angle (0%) was less successful than the PAT (10%) and SFT-B (93%). Using SFT-B to contact the lateral semicircular canal (90%) was significantly more successful than all current tools and to contact the sinodural angle (93%) was significantly more successful than all tools.

CONCLUSION

Using SFT-B enables enhanced accessibility of anatomical structures during TEES which may lead to less extensive bone removal to facilitate minimally invasive TEES.

[Endoscopically guided reconstruction of the ossicular chain-an introduction]

The term "endoscopic ossiculoplasty" refers to surgical methods with the intention to reconstruct the ossicular chain using endoscopic vision. Apart from malformations and injuries, inflammatory processes cause the majority of indications for ossicular reconstruction. This article offers a commented overview of current literature and preliminary personal experience.

Design, prototype development and pre-clinical validation of a novel instrument with a compliant steerable tip to facilitate endoscopic ear surgery

This work presents the design of a novel compliant steerable tip (CST) instrument to facilitate transcanal (or totally) endoscopic ear surgery (TEES). The evolution of the instrument's design is shown, where prototypes were evaluated by surgeons and their feedback was used to inform the design changes for the next prototype iteration. The final prototype enables the surgeon to articulate the compliant tip to achieve the desired bending curvature while automatically locking in place and providing dissection and suction capabilities. Pre-clinical validation testing was performed in goat and human cadaver models by two surgeons who successfully removed an allograft from the middle ear. Time and the number of blockages while suctioning saline in both cadaver models were measured and compared with current instruments used during TEES. The CST took significantly less time to suction saline within a flooded middle ear compared to the Panetti suction dissector (PSD) for atticus and underwent less blockages than the PSD for atticus, ear drum and sinus tympani instruments, Wilcoxon Method p < .05. Our study demonstrates the development and successful clinical evaluation of a minimally invasive surgical instrument designed to facilitate endoscopic approaches to the ear.

The Treatment of Cholesteatomas Involving the Antrum and Mastoid Using Transcanal Underwater Endoscopic Ear Surgery

OBJECTIVE

The aim of this study was to evaluate the feasibility and safety of transcanal underwater endoscopic bone resection (TUEBR) of the external auditory canal (EAC) for the management of cholesteatoma involving the antrum and mastoid.

STUDY DESIGN

Retrospective case review.

SETTING

Tertiary referral center.

PATIENTS

Pediatric and adult patients with primary cholesteatoma extending to the antrum and mastoid who underwent transcanal endoscopic ear surgery (TEES) with TUEBR between March 2016 and June 2017.

INTERVENTION

A rigid 2.7 mm diameter, 18 cm length Hopkins-rod telescope with an endoscopic sheath was inserted in the EAC and continuously perfused with saline during the dissection. TUEBR was performed to expose extensive cholesteatoma by using a high speed drill with curved burrs and a protected shaft. Next, removal of visible disease, reconstruction of the resected EAC, ossiculoplasty, and tympanoplasty were accomplished with TEES.

RESULTS

There were no intra- or postoperative severe complications such as facial palsy and inner ear injury except one patient suffering from secondary labyrinthitis. There was a negative linear relationship (r = -0.909) between the procedure time and procedure number of TUEBR. There was a weak relationship (r = 0.224) between the procedure time of TUEBR and the degree of the extension of cholesteatoma into the antrum and mastoid. There were two cases with residual cholesteatoma at 12 and 22 months follow-up postoperatively.

CONCLUSION

TUEBR is a safe and efficient technique for the resection of EAC bone and transcanal exposure of extensive cholesteatoma that would otherwise require mastoid dissection.

Can endoscopic ear surgery replace microscopic surgery in the treatment of acquired cholesteatoma? A contemporary review

Acquired cholesteatoma leads to significant morbidities while current surgical options remain a challenge. The principles of surgery include complete removal of disease, prevention of recurrence, and restoration of hearing function when possible. Traditionally, this has been performed using microscopes; however, a novel technique using endoscopes offers a new perspective on our understanding of anatomy, pathogenesis and surgical approaches. In recent years, various studies have demonstrated good outcomes with transcanal endoscopic ear surgery (EES) in cholesteatoma surgery. Nevertheless, the use of EES is not universal and remains controversial due to the efficacy of microscopes, specific limitations of endoscopes and the need to learn new skills. This review focuses on recent advances in EES for the treatment of acquired cholesteatoma, benefits, current challenges, and a discussion on the indications and contraindications of EES.

The first Malaysian experience on totally endoscopic ear surgery

Introduction:

Totally endoscopic ear surgery (TEES) is defined as exclusive application of endoscope transcanally in otologic surgery. This study is aimed to highlight indications and ear pathologies for TEES. In addition, intraoperative, early postoperative and delayed postoperative complications of TEES will be also described in this study.

Methodology:

This is a retrospective study of TEES performed by a single experienced and trained otologist in endoscopic ear surgery in a single institution between 1 July 2014 and 31 June 2018. A total of 43 patients were recruited in this study. Sociodemographic information, indications for TEES, ear pathologies, type of surgery performed and complications of TEES were analyzed.

Results:

The indications for TEES comprised middle ear lesion (65.1%), followed by second look surgery (14.0%), external auditory canal lesion (11.6%) and internal acoustic meatus lesion and surgery for conductive hearing loss which were 4.7%. Various external auditory canal pathologies encountered for TEES were ear canal osteoma (4.7%), acquired ear canal stenosis (2.3%) and tumor (4.7%). Regarding middle ear pathologies, limited atticoantral cholesteatoma accounted for most of the cases, 46.5%. Other middle ear lesions included adhesive otitis media (14.0%), recurrent cholesteatoma (14.0%), tumor (4.7%), otosclerosis (2.3%) and ossicular discontinuity (2.3%). Internal acoustic meatus lesion constituted 4.7% of cases. Some 4.7% of cases developed intraoperative complications, while early and delayed complications were 7.0%.

Conclusion:

TEES is a feasible surgical technique for diverse ear pathologies in the otologic specialty. It is also proven to be safe with good surgical outcomes.