Automated Objective Routine Examination of Optical Quality of Rigid Endoscopes in a Clinical Setting

Abstract

Rigid endoscopes degrade during clinical use due to sterilization, ionizing radiation and mechanical forces. Despite visual checks on functionality at the department of sterilization, surgeons are still confronted with suboptimal instruments as it is difficult to assess this degradation in an objective manner. To guarantee that endoscopes have sufficient optical quality for minimal invasive surgery, an experimental opto-electronic test bench has been developed in order to be used at the department of sterilization. Transmission of illumination fibres and lens contrast values are stored in a database to enable empirical criteria to reject endoscope for further clinical usage or to accept endoscopes after repair. Results of the test bench are given for an eight month period, where a trained operator performed 1599 measurements on 46 different types. Stability of the system, trends in quality of clinical endoscopes, and effect of repair or replacement were assessed. Although the period was too short to draw firm conclusions, a slow downwards trend in quality of clinically used endoscopes could be observed. Also, endoscopes generally improve in quality after repair or replacement, while endoscope replacement seems to slightly outperform endoscope repair. To optimize the measurement process, a new system is being developed requiring less user interaction and measuring more optical parameters of an endoscope. By commercializing this system, we hope that measurements at different hospitals will give improved insight which acceptance and rejection criteria to use and which factors (usage, cleaning protocol, and brands) determine the economic lifetime of endoscopes.

An Actuated Variable-View Rigid Scope System to Assist Visualization in Diagnostic Procedures

“…The scope is methodically advanced along a narrow passageway and maneuvered to examine the tissue linings, identify any abnormal growths such as polyps, and determine the underlying cause of issues. While a flexible endoscope can be also be used, a rigid scope offers distinct advantages, such as superior optical resolution, ease in sterilization, ease in maintenance, and lower cost [2] , [3] , [4] . This has led to wider adoption of the rigid scope in diagnostic procedures such as rhinoscopy [5] , cystoscopy [6] , and transvaginal endoscopy [7] .…”

“…Examples include EndoCAMeleon - Karl Storz and Endorizon Sinuscope - Olympus. These scopes enable variable viewing direction in one plane, and when combined with 360° rotation of the scope shaft along its axis, increases the overall field of view [2] , [3] , [8] .…”

Evaluation of the ScopeControl endoscope test system in six hospitals in The Netherlands

“…In order to consider the practical feasibility in the workflow, we tested the system at the sterilization department of the UMC Utrecht [4]. However, as the system was experimental, it required dedicated technically skilled people to operate it.…”