Endoscopy Equipment D. J. McMahon 150512 rev cewood 2018-01-29
Key Points Medical Video 2 - Endoscopy: Know the proper installation and hazards associated with xenon lamps Know what an insufflator is and what it does Know the medical gas used for ensufflation Know 4 ways to archive video images Understand what a Charge-Coupled Device (CCD) digital video chip is OUTLINE: - Endoscope: for colonoscopy, gastroscopy, bronchoscopy - Camera - CCD charge-coupled device (imaging chip) - Camera Processor - Light Source: xenon lamp or LED - Display - Recording Methods: video tape (no longer used) make a hard copy make a digital video disc (DVD) send it to a flash drive send it to a server for later retrieval - Insufflator - Surgical Microscopes - Test Equipment
Colonoscopy Gastroscopy
Bronchoscopy
Endoscopic Systems The Essentials: > camera > endoscope > light source > camera processor > display
Endoscopic Cameras -
Charge-Coupled Device (CCD) The heart of solid state imaging much more: https://graphics.stanford.edu/courses/cs178-09/lectures/sensors-16apr09.pdf
http://www.specinst.com/what_is_a_ccd.html
Representative CCD sizes and areas Type Aspect Ratio Width mm Height mm Diagona l mm Area mm 2 Relative Area 1/6" 4:3 2.300 1.730 2.878 3.979 1.000 1/4" 4:3 3.200 2.400 4.000 7.680 1.930 1/3.6" 4:3 4.000 3.000 5.000 12.000 3.016 1/3.2" 4:3 4.536 3.416 5.678 15.495 3.894 1/3" 4:3 4.800 3.600 6.000 17.280 4.343 1/2.7" 4:3 5.270 3.960 6.592 20.869 5.245 1/2" 4:3 6.400 4.800 8.000 30.720 7.721 1/1.8" 4:3 7.176 5.319 8.932 38.169 9.593 2/3" 4:3 8.800 6.600 11.000 58.080 14.597 1" 4:3 12.800 9.600 16.000 122.880 30.882 4/3" 4:3 22.500 18.000 28.814 405.000 101.784 Other image sizes as a comparison APS-C 3:2 25.100 16.700 30.148 419.170 105.346 35mm 3:2 36.000 24.000 43.267 864.000 217.140 645 4:3 56.000 41.500 69.701 2324.000 584.066
https://graphics.stanford.edu/courses/cs178-09/lectures/sensors-16apr09.pdf
Single-Chip Cameras Single-chip cameras use a Bayer filter, which allows them to detect only one-third of the color information for each pixel on the CCD. The other two-thirds must be interpolated, resulting in a lower effective resolution Bayer filter Three-Chip Cameras Philips type trichroic beam splitter prism Three-chip cameras use a prism to split the image into each of the three primary colors, each of which is received by every pixel on a separate CCD or CMOS camera, giving better resolution and sharpness.
Cameras:
Camera Controllers:
Connector abuse! Damage from abusive handling of the camera connector.
Endoscopic Light Sources - use a 300-400 watt xenon lamp - color balanced to 6500 K - power supply ignites the lamp with a brief pulse in KV range - light output is varied with a mechanical shutter - lots of heat generated
xenon lamp
Changing Xenon Lamps in Light Sources > Xe Lamps are ~$300. Be sure the lamp needs changing! > Do NOT touch the lens of the lamp with your fingers. > Heat sink compound is essential to maximum lamp life. - clean most of the old compound from the heat sink parts. - apply a thin layer of new heat compound to the contacting surfaces. > Xe lamps have high internal pressure. - should wear eye protection when handling. Handle with care even when discarding. > Good practice to vent the lamp before discarding.
Thermal compound: thick liquid of electrically conductive AND thermally conductive material. Typical materials are aluminum oxide, boron nitride, zinc oxide, and aluminum nitride.
Newer endoscope light sources use LEDs: Same output (lumens) as xenon lamps Adjustable color & color temperature Much cooler Much more efficient
Enhanced imaging for endoscopy - Typical image of an esophagus under normal light.
Same image under Olympus Narrow Band Imaging. Specific color wavelengths are filtered to emphasize features of human tissue.
Surgical Microscopes - - Configurable for one to three surgeons - Integrate optics, a light source, and video - Are very expensive - Almost always maintained and repaired by a company FSE, but - CE needs to troubleshoot and replace lamps
Leica OH5
Zeiss Pentero 900
Older units:
Endoscopic Systems Ancillary Devices: > insufflator > video tape recorder > video printer > digital storage device(s)
Insufflators - create a space in the abdomen for endoscopic procedures with carefully regulated CO 2 typical pressure in the range of 15-20 mmhg within the abdomen usually display pressure, flow, and total volume of CO 2 used
Archiving the images: - put it on video tape (no longer used) - make a hard copy (still images only) - make a digital video disc (DVD) (better) - send it to a flash drive (even better) - send it to a server for later retrieval (best)
be kind, rewind
The Digital Versatile Disc (DVD): Standardized as the Universal Disc Format (UDF), as ISO-13346. Standard DVD s are 12cm in diameter, and are written or read by a 650nm laser. They are available as single-layered: 4.70 GB capacity or dual-layered: 8.54 GB capacity
DVD+R, DVD+RW, DVD-R, DVD-RW: R means recordable once RW means re-recordable (Read-Writeable)..R discs record data once, then act as DVD-ROMs...RW discs can record and erase multiple times, so act as a DVD-RAM.
Major Players in Medical Video Systems : Stryker Olympus Conmed-Linvatec Karl Storz Medical Video Monitors: Sony, NDC, Planar, many others
Video display pattern generators
Sencore video display test equipment:
Flexible Endoscopes
Typical endoscope cross-section:
Joint Commission requirements for endoscopy: EC.02.04.01: - CE must inventory all endoscopes - CE must document all maintenance on endoscopes - but CE is not obligated to perform that maintenance. Endoscope processing is done by the user department in almost every setting. However, CE usually takes care of the endoscope processors.
ECRI: Top 10 Health Technology Hazards for 2016 #1: Inadequate Cleaning of Flexible Endoscopes before Disinfection Can Spread Deadly Pathogens Summary The failure to adequately reprocess contaminated instruments that is, to clean and disinfect or sterilize them before using them on subsequent patients can lead to the spread of deadly pathogens. A key aspect of effective reprocessing is cleaning biologic debris and other foreign material from instruments before the disinfection or sterilization step. If this precleaning is not carried out effectively, the disinfection or sterilization step may not be effective. Flexible endoscopes in general, and duodenoscopes in particular, are of specific concern because their complex design and long, narrow channels can make effective cleaning difficult. A series of fatal carbapenem-resistant Enterobacteriaceae (CRE) infections that attracted a lot of attention in 2014 and 2015 illustrates this concern: The deaths were associated with the use of duodenoscopes that had not been successfully disinfected between uses. Facilities need to emphasize to their reprocessing staff that inattention to the cleaning steps within the reprocessing protocol can lead to deadly infections.