Objective: This document describes the technique of intracameral anesthesia
and examines the available evidence to address questions about its effecti
veness, possible corneal endothelial and retinal toxicity, and the optimal
and maximal dose.
Methods: A literature search conducted for the years 1968 to 2000 retrieved
over 180 citations that matched the search criteria. Panel members and a m
ethodologist reviewed this information, and it was evaluated for the qualit
y of the evidence presented.
Results: Some studies report effectiveness of intracameral anesthesia while
others report no effect. In those studies showing an effect, levels of pai
n in the groups that were compared were low. Short-term studies seem to ind
icate that preservative (methylparaben)-free lidocaine 1% is well tolerated
by the corneal endothelium but that higher concentrations of lidocaine are
toxic. There is some evidence of electroretinogram changes after exposure
to lidocaine or bupivacaine.
Conclusions: The ideal timing and placement of intracameral anesthesia has
not been determined. Because topical anesthesia alone is effective, surgeon
s may elect to use intracameral anesthesia for incremental pain control in
patients who cannot be adequately managed with topical alone. Appropriate p
atient selection is important when using this method of anesthesia. While s
hort-term studies seem to indicate safety, long-term effects are unknown. P
atient preferences for anesthesia are not well studied.