Analgesia for retrobulbar block--comparison of remifentanil, alfentanil and fentanyl.

Background: The injection of retrobulbar block is associated with significant pain and discomfort. Therefore a short-acting IV analgesic before retrobulbar injection has been advocated.

Objective: To compare remifentanil, alfentanil and fentanyl in providing analgesia for retrobulbar block injection.