Evaluation of Computer-assisted Image Enhancement in Minimal Invasive Endoscopic Surgery^[*]

Summary

Objectives: This paper focusses on the evaluation of the usage of computer-aided image processing methods for minimal invasive surgery. During video endoscopy of visceral cavities the images are displayed directly on the monitor without further processing. In the course of the operation the former good quality of the images decreases due to typical disturbances like bleeding, smoke or flying particles. These disturbances can be reduced by using image processing methods like color normalization, temporal filtering or equalization.

Methods: In this double-blinded analysis, 14 surgeons with different levels of experience evaluated 120 image pairs and 5 image sequences, directly comparing original and processed images or movies.

Results: Color normalization and equalization proved to significantly enhance video endoscopic images. With regard to temporal filtering, an improvement could be seen in the image sequences with filter size 5 being a greater enhancement than filter size 3. Comparing the state of experience and its influence on the results, it occurred that the experienced surgeons preferred the original color while altogether agreeing that the color-normalized images were better.

Conclusions: The results obtained in the present evaluation show that the image processing methods which were used can significantly improve the quality of video endoscopic images. As a result of this, necessary lavages of the operated area are reduced and a better overview and orientation for the surgeon can be reached.

Keywords

Minimal invasive surgery - computer-aided image processing - video endoscopy - evaluation - image enhancement

• References

• 1 Zhang Z. On the Epipolar Geometry Between Two Images with Lens Distortion. In: Proceedings International Conference Pattern Recognition (ICPR), Wien, Aug. 1996: 407-11.
• 2 Paulus D, Csink L, Niemann H. Color cluster rotation. In: Proceedings of the International Conference on Image Processing (ICIP), Chicago, October. 1998. IEEE Computer Society Press;
• 3 Vogt F, Paulus D, Schick CH. Fast Implementations of Temporal Color Image Filtering. In: 7. Workshop Farbbildverarbeitung. Paulus D, Denzler J. (eds) Erlangen; 2001. Bd. 34, Nr. 15 89-98.
• 4 Tsai RY. A Versatile Camera Calibration Technique for High-Accuracy 3D Machine Vision Metrology using Off-the-Shelf TV Cameras and Lenses. IEEE Journal of Robotics and Automation 1987; (03) 323-44.
• 5 Vogt F, Klimowicz C, Paulus D, Hohenberger W, Niemann H, Schick CH. Bildverarbeitung in der Endoskopie des Bauchraums. In: 5. Workshop Bildverarbeitung für die Medizin. Handels H, Horsch A, Lehmann T, Meinzer H-P. (Hrsg.) Springer: 2001: 320-324.