Abstract: Tool mount adaptors for interfacing a medical instrument with a medical insertion device are provided. The tool mount adaptor includes a collar for holding a medical instrument wherein the tool mount adaptor is releasably attachable to the medical insertion device. Cannula holder assemblies for a medical insertion device are also provided. The cannula holder assembly includes: (a) a cannula track; and (b) a cannula carriage slideably mounted on the cannula track comprising a cannula holder mount and a demobilizer. Medical insertion devices comprising the tool mount adaptors and/or cannula holder assemblies are also provided together with methods of using the medical insertion devices in diagnostic and/or therapeutic applications.