A tool guide for guiding an end effector of a robotically controlled surgical instrument from a position outside a patient body to a position in close proximity to an internal surgical site within the patient body is provided. The tool guide typically comprises a body, a seat formation on the body, the...http://www.google.com.au/patents/US6620173?utm_source=gb-gplus-sharePatent US6620173 - Method for introducing an end effector to a surgical site in minimally invasive surgery
