Role of hyaluronidase as an adjuvant in local anesthesia for cataract surgery.

Cataract surgery ranks among the commonest procedures performed worldwide. Approximately 51% of blindness worldwide is related to cataracts, affecting about 65.2 million people worldwide and more so in developing countries. Over the years, there has been a significant evolution in the surgical techniques of cataract extraction. The advancement in phacoemulsification machines, phaco-tips, and the availability of ophthalmic viscoelastic devices have played a substantial role in cataract surgery such that they are faster and more controlled than before. Similarly, anesthetic techniques in cataract surgery have advanced significantly from retrobulbar, peribulbar, and sub-Tenon's blocks to topical anesthesia. Though topical anesthesia eliminates the possible complications of injectable anesthesia, it is not suitable for use in uncooperative, anxious patients, pediatric age groups, and patients with cognitive disabilities. Hyaluronidase is an enzyme that breaks down hyaluronic acid in the retrobulbar tissue, facilitating uniform diffusion of the anesthetic drug and hastening the onset of anesthesia and akinesia. Hyaluronidase has been used in the last 80 years successfully as an adjuvant in retrobulbar, peribulbar, and sub-Tenon's blocks. Initially, the hyaluronidase enzyme was animal-derived and of bovine and ovine sources. Recombinant human-derived hyaluronidase, which has lesser allergic reactions, impurities, and toxicity, is now available. There is conflicting evidence regarding the efficacy of hyaluronidase as an adjuvant in retrobulbar and peribulbar blocks. This article summarizes a brief review of the literature on the role of hyaluronidase as an adjuvant in local anesthetic blocks in ophthalmic surgeries.

Use of hyaluronidase in plastic surgery: A review.

Hyaluronidase is a family of enzymes that degrade hyaluronic acid (HA). It is found to increase vascular permeability and temporarily disrupt the extracellular matrix, promoting diffusion of substances through tissues. Alongside its applications in ophthalmology, obstetrics and gynaecology, musculoskeletal medicine, radiology and drug and fluid administration, hyaluronidase has a number of roles in the field of plastic surgery. The popularity of HA fillers in recent years has led to an increase in the usage of hyaluronidase in the treatment of filler-related complications. The purpose of this article is to review the current and future uses of hyaluronidase within the field of plastic surgery. Hyaluronidase is used as an adjunct to local anaesthetics in skin infiltration, skin graft harvesting, tumescent analgesia, managing complications of dermal fillers, treatment of extravasation injury, prevention and management of oedema, treatment of ganglion and management of scars. However, it has some limitations. Hyaluronidase is known to interact with a number of common medications. Several case reports also highlight the risk of allergic reaction to the substance. Although rare and usually mild, hyaluronidase has the potential to cause anaphylaxis. Other adverse effects include bruising and swelling. Overall, hyaluronidase appears to be a very safe, cheap and effective medication for a variety of uses in the field of plastic surgery and beyond.