Time Flow Study to Assess Opportunities to Improve Efficiency in Endoscopic Tympanoplasty.

BACKGROUND: To characterize the workflow during transcanal totally endoscopic tympanoplasty by recording the time and instrumentation used for different steps in the procedure. This analysis aims to identify aspects of instrumentation and surgical technique that could be modified to improve surgical efficiency. METHODS: Thirty-one endoscopic tympanoplasty procedures were observed at a single academic center. Patient age ranged from 2.7 to 17.8 years. The procedure was separated into distinct steps. The duration in minutes and the instruments used were recorded by an independent observer. RESULTS: Raising the tympanomeatal flap (median 9.82 minutes) and positioning the graft and replacing the flap (median 9.13 minutes) took significantly longer than all other steps (P < .05, Wilcoxon method). Teaching a trainee significantly increased step duration by a total of 32.8 minutes (P < .05, Wilcoxon method). There was no correlation between age of the patient, side of the ear, surgical technique, or graft type, and duration of surgery. Suction instruments with a functional tip (dissector or knife tip) were most commonly used to dissect and maneuver soft tissue while maintaining the surgical field clear of blood. CONCLUSION: As elevation of the tympanomeatal flap and graft placement are the most time-consuming steps in endoscopic tympanoplasty, especially for surgical trainees, surgical efficiency could most dramatically be enhanced by modification of instrumentation or technique to facilitate these steps. Modification of simpler steps such as hair trimming and ear canal packing have less potential for shortening surgical duration.

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.

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

OBJECTIVE: This study aimed to identify limitations and challenges associated with existing instruments and techniques used in totally endoscopic ear surgery (TEES). BACKGROUND: Otologic instruments, traditionally developed for two-handed surgery with operating microscopes, are not necessarily optimized for the TEES environment. Better understanding of technical challenges and the limitations of current instrumentation may allow advances in instrument design for TEES surgery. METHODS: This cross-sectional study employed a mixed-methods nine-question survey that was distributed internationally to surgeons with an interest in TEES. Respondents were asked to classify their TEES experience and instrumentation used, rate their need for better instrumentation to address six TEES-related challenges using visual analog scales, and comment on how to modify or develop new instrumentation. RESULTS: With 51 respondents, we quantified a need for better instruments to address the following 6 potential TEES challenges ordered from greatest to least need: 1) reaching structures visualized by the endoscope, 2) dissection and removal of cholesteatoma, 3) cutting and/or removing bone, 4) bleeding control, 5) keeping the endoscope lens clean, 6) moving and positioning a graft into the intended place. The majority of surgeons perceive a need for improved instrumentation to address each challenge. Challenges 1) and 2) were associated with significantly greater need than the others (p < 0.05, Wilcoxon method for nonparametric pairwise comparisons). CONCLUSION: In addition to highlighting and quantifying some of the common TEES challenges, these findings provide valuable insight into the design requirements for developing improved surgical instrumentation and techniques.