Central corneal thickness and applanation tonometry.

after sub-Tenon anesthesia In their recent article, 1 Subbiah et al. noted that a rigid sub-Tenon cannula caused complications such as a retrobulbar hemorrhage, albeit rarely. The authors concluded that a ‘‘soft cannula’’ could be an ideal alternative for sub-Tenon injection in high-risk patients. We reported the same thing in our Sandwell technique, in which the soft plastic sheath of a Venflon was used to deliver the local anesthetic agent in the sub-Tenon space. This prevents injury to blood vessels in a highly vascular region during an essentially blind procedure. It is probably because our report was published in April 2007 that Subbiah et al. overlooked this very effective technique that addresses the point raised in the article. In our practice, we have found that the ultrashort version is not as effective as the Venflon sheath, as it often does not deliver the anesthetic agent to the actual retrobulbar region. Since our report, we have used this technique in all cases and have had no complications.