Single quadrant sub-Tenon's block. Evaluation of a new local anaesthetic technique for eye surgery.

The sub-Tenon's technique uses blunt dissection and a blunt probe to inject local anaesthetic into the posterior sub-Tenon's space. This avoids the potentially catastrophic complications which result from passing a sharp needle blindly into the orbit and retrobulbar space. The anatomy of Tenon's capsule and the block technique is described. Results of the block quality and degree of patient comfort from 300 consecutive sub-Tenon's blocks are also described. No significant complications occurred in this series. Single-quadrant sub-Tenon's block offers an excellent quality of anaesthesia, is virtually painless to perform and avoids complications due to passage of a sharp needle into the orbit.