In 1910, Julius Hirschberg, MD, reported using 2% cocaine chloride solution for topical anesthesia for thousands of cataract surgeries without a single disadvantage. Many Third World countries have routinely performed cataract extractions with topical anesthesia and radial keratotomy has historically been performed with topical anesthesia.

Injectable anesthesia of any kind inherently has risks related to the needle even though the periocular approach lessened those risks (Table 1). I began using topical anesthesia for cataract extraction in 1992 after reading the article describing Fichman's technique.<sup>1 Bloomberg L.B. A topical anesthesia technique using an anesthetic ring Ocular Surgery News Aug 1993 ;  15 : 4243

Cliquez ici pour aller à la section Références</sup> Initially, I carefully selected patients for whom I would use topical anesthesia. Presently, I am using topical anesthesia for nearly all of my anterior segment surgery.<sup>1 Bloomberg L.B. A topical anesthesia technique using an anesthetic ring Ocular Surgery News Aug 1993 ;  15 : 4243

Cliquez ici pour aller à la section Références, 2 Bloomberg L.B., Pellican K.J. Topical anesthesia using the Bloomberg SuperNumb Anesthetic Ring J Cataract Refract Surg 1995 ;  21 : 16-20

Cliquez ici pour aller à la section Références</sup> I have found it to be an effective and reliable method of obtaining ocular anesthesia for cataract surgery, radial keratotomy, automated lamellar keratoplasty, and other anterior segment procedures. By using topical anesthesia, I eliminate any risk associated with a needle being placed near delicate orbital structures.

After doing my first few cases using topical drops, I noticed that some of the patients did seem to have mild discomfort during the procedure, especially when the speculum was inserted and removed. The patient often would squeeze their eyelids together during the procedure indicating to me that they had some discomfort. I also noticed “squeezing” in the videos of other surgeons advocating the use of topical anesthesia.

I began to think of ways to administer the anesthetic that might help assure the patient's comfort and that would help to maintain the anesthetic effect throughout the entire procedure, particularly in the event of a prolonged surgery. Also, knowing that the anesthetic can be toxic to the cornea, I was concerned that just dropping the anesthetic directly onto the corneal epithelium throughout the operation might lead to excessive drying and sloughing of epithelial cells.

I developed the Bloomberg Ophthalmic Ring (Ultracell Medical Technologies, North Stonington, CT) to enhance patients' comfort and to keep the topical anesthetic away from the cornea. The Ophthalmic Ring<sup>1 Bloomberg L.B. A topical anesthesia technique using an anesthetic ring Ocular Surgery News Aug 1993 ;  15 : 4243

Cliquez ici pour aller à la section Références, 2 Bloomberg L.B., Pellican K.J. Topical anesthesia using the Bloomberg SuperNumb Anesthetic Ring J Cataract Refract Surg 1995 ;  21 : 16-20

Cliquez ici pour aller à la section Références</sup> stays on the eye throughout the surgery. It lays down a continuous release of the anesthetic agent on the ciliary nerves outside of the limbus, thereby maintaining a good level of anesthesia for the entire procedure. The ring can be resaturated if necessary to prolong the effect of the anesthesia. For radial keratotomy, the anesthetic ring also serves to cushion the teeth of the fixation ring, thereby keeping the patients more comfortable.

Even with an unexpected surgical complication that may prolong a procedure, the Bloomberg Ophthalmic Ring helps to ensure that the patient will not feel any discomfort.

Because the Bloomberg Ophthalmic Ring is in the shape of a donut with a diameter slightly larger than the corneal diameter, it has the added benefit of keeping the potentially toxic anesthetic agent away from the corneal epithelium. On smaller eyes, the ring can be opened and one end can be pulled to the side to have easier access to the incision site.