Retrobulbar block

Blocks:

optic nerve
trigeminal nerve
retrobulbar muscles

Technique:

22-gauge, 2.5-in spinal needle is placed through the skin perpendicular to the skull in the orbital fossa, just caudal to the posterior aspect of the boney dorsal orbital rim.
The needle is advanced caudally to the globe until it
reaches the retrobulbar orbital cone. When the needle
advances to this location, the eye will have a slight
dorsal movement as the needle passes through the
fascia of the dorsal retrobulbar cone into the retrobulbar
space. Once positioned, 10–12 ml of local anaesthetic is
injected into the retrobulbar space. During the injection,
the globe is pushed externally (i.e., slight exophthalmos),
indicating an accurate placement of the local.