Quantitative Measurements in Otological Surgery: Use of an Endoscopic Integrated Multipoint Laser System

By June 7, 2019

Hall, Andrew1; Butler, Colin1; Nash, Robert1; Xie, Carol1; Varadharajan, Kiran1; Sethakumar, Priya1; Navratanam, Annakan1;
1 Department of Paediatric Otolaryngology, Great Ormond Street Hospital, London, UK.

Introduction:
Measurement of tympanic membrane perforation size and ossicular discontinuity is classically performed with reference to otological instruments intraoperatively and may prove a time-consuming stage of surgery. Endoscopic ear surgery offers an opportunity to utilise technological advances allowing intra-operative measurements of underlying pathology to ensure accuracy of middle ear reconstruction. Initial evaluation of technologies in simulation-based assessment may allow future clinical application within otology.

Methods:
Patients: Nil (Simulated environment)

Intervention: Diagnostic

A 4.4mm endoscope included a multipoint-laser measurement system (Karl Stortz Techno Pack X) projecting 49 laser beam points into the optical axis of the endoscopic view. This was utilised by six otolaryngology surgeons within both external and middle ear simulator environments to validate the accuracy of the measurement technique. Endoscopic integrated multipoint laser measurements were taken of simulated pathologies including tympanic membrane perforations and simulations of ossicular discontinuity. Three measurements were taken by each individual per pathology and compared to standard measurement techniques.

Outcome Measure:
Measurement of pathology (mm)

Results:
Levels of precision were demonstrated to a 100thof a millimitre measuring both point to point (perforation size) and depth (gap from long process to stapes). This pilot study suggests potential utility for further integration within rigid endoscope technology used routinely in endoscopic ear surgery.

Conclusions:
Our data in the simulated environment suggests this area offers an ongoing opportunity to the endoscopic ear surgical community. Further development of laser multi-point measurement endoscopic technology and engagement with optical engineers as to our surgical goals will allow advances to optomise future otological surgery.