This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a colleague Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Fanning, G. L. Search for Related Content PubMed PubMed Citation Articles by Fanning, G. L.

---

LETTERS

Hyaluronidase in Ophthalmic Anesthesia

Hauser-Ross Eye Institute Sycamore, IL

To the Editor:

Kallio et al. (1) have shown that a commonly used concentration of hyaluronidase (7.5 U/mL) is at least twice that required to produce an acceptable orbital block. I wish they had used an even smaller concentration in their study. For several years, using a block technique similar to theirs, I have had a 95% incidence of >95% akinesia using no more than 1–1.5 U/mL.

The success of an orbital block is influenced more by the anatomical location of the injectate than by the use of hyaluronidase. Nonetheless, using it helps to disperse the injectate, improves the block, and reduces the incidence of posterior vitreal pressure associated with a bolus of solution sitting behind the globe. As evidenced by the rash of extraocular muscle dysfunctions reported during a recent hyaluronidase shortage (2,3), using hyaluronidase also prevented myotoxicity in these delicate muscles, although the mechanism has yet to be explained.

All who perform orbital regional anesthesia should heed the message that 7.5 U/mL is much more hyaluronidase than is necessary to achieve a good block. Using small concentrations will save a lot of money in a busy ophthalmic practice.

References

1. Kallio H, Paloheimo M, Maunuksela E-L. Hyaluronidase as an adjuvant in bupivacaine-lidocaine mixture for retrobulbar/peribulbar block. Anesth Analg 2000; 91: 934–7.[Abstract/Free Full Text]
2. Brown SM, Brooks SE, Mazow ML, et al. Cluster of diplopia cases after periocular anesthesia without hyaluronidase. J Cataract Refract Surg 1999; 25: 1245–9.[Web of Science][Medline]
3. Troll G, Borodic G. Diplopia after cataract surgery using 4% lidocaine in the absence of Wydase (sodium hyaluronidase) [letter]. J Clin Anesth 1999; 11: 615–6.

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a colleague Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Fanning, G. L. Search for Related Content PubMed PubMed Citation Articles by Fanning, G. L.