gms | German Medical Science

102. Jahrestagung der DOG

Deutsche Ophthalmologische Gesellschaft e. V.

23. bis 26.09.2004, Berlin

First results of a software-based microscope-tracking system used for anterior segment eye surgery

Meeting Abstract

  • corresponding author T. Lischka - Department of Ophthalmology, Center of Head Care and Dermatology, University Medical Center Hamburg-Eppendorf, Hamburg
  • A. Kijak - Department of Ophthalmology, Center of Head Care and Dermatology, University Medical Center Hamburg-Eppendorf, Hamburg
  • S.-D. Schulz - Vision Systems, Technical University Hamburg-Harburg, Hamburg
  • M. Burisch - Vision Systems, Technical University Hamburg-Harburg, Hamburg
  • B. Zessack - Vision Systems, Technical University Hamburg-Harburg, Hamburg
  • R.-R. Grigat - Vision Systems, Technical University Hamburg-Harburg, Hamburg
  • G. Richard - Department of Ophthalmology, Center of Head Care and Dermatology, University Medical Center Hamburg-Eppendorf, Hamburg;

Evidenzbasierte Medizin - Anspruch und Wirklichkeit. 102. Jahrestagung der Deutschen Ophthalmologischen Gesellschaft. Berlin, 23.-26.09.2004. Düsseldorf, Köln: German Medical Science; 2004. Doc04dogDO.17.06

The electronic version of this article is the complete one and can be found online at: http://www.egms.de/en/meetings/dog2004/04dog156.shtml

Published: September 22, 2004

© 2004 Lischka et al.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by-nc-nd/3.0/deed.en). You are free: to Share – to copy, distribute and transmit the work, provided the original author and source are credited.


Outline

Text

Objective

Last year we presented a software for automatic microscope tracking for anterior segment eye surgery. Here we present first results of the use of this system for automated microscope tracking.

Methods

The prototype consisted of a commercial PC which was connected to the microscope using a computer interface. The software was devided in two applications: One application ran the image processing algorithms and carried out the automated microscope movements. The user interface was presented on a touchscreen. Complete control over every parameter was provided by a second application. It was possible to ran both applications on the same PC or on two different PCs connected via local network. A second PC was used for extensive storage of images and data. The circular iris was chosen as a constant feature for image centering, the virtual midpoint of the iris in the microscopic field was computed continuously. For automated microscope tracking a distinct tolerance for the iris position was defined. Only if the Iris crossed this tolerance area, an automated microscope-movement was initiated. The size of the tolerance range was variable. On the touchscreen the actual microscopic field was shown and the tolerance area was superimposed.

Results

The tracking system processed 10 images per second, automated microscope tracking was delayed with a maximum of one second. While using the tracking-system it turned out that a change of magnification required also a change in the size of the tolerance area. After modification of the software the use of the tracking system led to an improved centering of the surgical field and the use of the X-Y-coupling was reduced.

Conclusions

Using the tracking system the surgical field is centered optimally. A manual adjustment of the operating microscope becomes redundant, the surgeon is relieved of this task.