!!! Continuous Medical Cataract Knowledge [{Image src='Success Story - Cataract/logo_KIT.png' align='right' style='margin-right:30px; margin-left:20px'}] !! Medical Background In the ophthalmology, the so called cataract surgery is the most important surgical intervention with about 700.000 operations/year only in Germany. The old and cloudy human lens can be removed and must be replaced by a new clear intraocular lens (IOL). Because of no prevention or medical treatment, the operation itself should be performed in patient related best manner. Concerning optimisation of surgical interventions at human eyes, a knowledge based assistant system is developed, to support the ophthalmic surgeons before real intervention at human eyes. !! Methods The clinical expert knowledge is available in frame and rule-based structures. The main advantage of the computer-based support is the intelligent correlation of the whole cataract environment and the possibility of giving decision support for the surgeons by logical explanation. The passive knowledge is done by wikipedia-like presentation. The visualisation is given by semantic net structures and supports knowledge acquisition and explanation by a natural language access. !! Aims The clinical experts can simulate the operation process by logical decisions and analyse the results of the simulated operation. So, for complex processes the decisions and parameters can be changed. Another feature is the function as tutorial system for young surgeons. The project WISSASS (Wissensbasiertes Assistenzsystem in der Kataraktchirurgie) is sponsored by the german Federal Ministry of Economics and Technology (Bundesministeriums für Wirtschaft und Technologie - BMWi) in Berlin. In health care, advanced patient contentment and reduced postoperative costs are the main goals to develop such a computer-based decision support system for opthalmic surgeons. The project is performed by the [national research center in Karlsruhe|http://www.kit.edu] (KIT) and the specialized company [denkbares GmbH|http://www.denkbares.com] in Würzburg, together with clinical partners in Karlsruhe. The project is funded by the german Federal Ministry of Economics and Technology (Bundesministeriums für Wirtschaft und Technologie - BMWi) under KF2960301BZ1 (WISSUS - KIT) and BF2959901BZ1 (WISSKONT - denkbares).