Abstract: The present invention relates to an adapter apparatus for medical endoscopes. The present invention comprises an apparatus for inserting tightly into a typical access port of a medical endoscope. Such adapter apparatus permits certain medical implements, such as optical fibers for laser surgery, to be inserted therethrough for treatment of the patient. This adapter apparatus also permits simultaneous passage therethrough of saline or other irrigation fluid without the prior removal of the medical implement. This permits rapid, simultaneous irrigation to proceed directly through an existing endoscope channel.