A flexible endoscope for insertion into a body cavity for visual observation and medical procedures. A vacuum line slidable in a tube in the endoscope for projection beyond the distal end of the endoscope, with vacuum control, providing for removal of blood clots and the like while observing the operation....http://www.google.de/patents/US4146019?utm_source=gb-gplus-sharePatent US4146019 - Multichannel endoscope
