EyeWorld Asia-Pacific September 2020 Issue

FEATURE 12 EWAP SEPTEMBER 2020 amniotic membrane alone as the graft. He said this technique is not as technically difficult as conjunctival autografting, but it has a higher recurrence rate. Dr. Hovanesian reserves this technique for cases where there is no conjunctiva (due to scarring, for example) for him to harvest. “Typically though, I don’t do that procedure because it is possible to harvest conjunctiva,” he said. Taking it all a step further, Dr. Hirst described his intensive P.E.R.F.E.C.T. for PTERYGIUM (pterygium extended removal followed by extended conjunctival transplantation) technique for pterygium surgery, which he has shown in a prospective study to have a 0.1% recurrence rate. 2 But first, he took EyeWorld on a history lesson that led to this technique’s development. Moving back to Australia in 1986 from the U.S., Dr. Hirst said he was “astounded by the rate and size of pterygia here.” At that time, pterygia were snipped off and treated with radiotherapy. This dangerous method, Dr. Hirst said, could have severe complications, such as loss of the eye or thinning of the sclera. It’s now rarely used in Australia. Dr. Hirst said he started using Dr. Kenyon’s conjunctival autograft technique shortly after the paper was published. “The results were what everyone expected, between 5 and 15% risk of recurrence, and the cosmetic results were frequently horrible. That persuaded me that I needed to do something better,” he said. Over the next decade, Dr. Hirst said he slowly expanded the quantity and quality of conjunctival autografting in his practice. One pivotal change he made was performing a large tenonectomy. “When I did that, the recurrence rate dropped to almost zero, but as a secondary phenomenon, removing that much tenons allowed the conjunctiva to retract to its normal position, which left a huge hole.” Dr. Hirst said he filled this hole with a large autograph (13x13–15x15 mm) from the superior conjunctiva. He sutures the graft with two radial incisions to the sclera with no tenons in between. “Ultimately, that made sure the scar was invisible in those two areas. The only area where I still have a scar is nasally … because I’m suturing conjunctiva to conjunctiva,” he said. “The way I dealt with that was to excise the semi-lunar fold, and to use the suture line to create a new semi-lunar fold with the scar under the new semi-lunar fold.” Dr. Hirst said he has performed more than 4,000 pterygium surgeries (3,500 primary pterygia) with this technique and has had only one recurrence following primary pterygium surgery, which he said was more than 8 years ago. While Dr. Hovanesian said the traditional conjunctival autograft technique can take about 5 minutes in the OR, Dr. Hirst said his procedure takes upward of an hour. In Australia—and likely around the globe for that matter—Dr. Hirst said pterygium is viewed as a trivial disease deserving only a simple surgical solution. However, his technique is a complex, difficult surgery. “In all my attempts to find ophthalmologists in Australia who wish to learn this, I’ve managed to find four,” Dr. Hirst said. However, he said that the technique’s low recurrence rate with good, predictable cosmetic outcomes makes the procedure worth it to him and his patients. Mitomycin adjuvant Both Dr. Hirst and Dr. Hovanesian have strong reservations about use of mitomycin in pterygium surgery. Dr. Hirst said mitomycin has its uses in ophthalmic surgery, but not for pterygium. “It’s unnecessary and far too dangerous for pterygium surgery,” he said. Preoperatively, this patient had a pterygium extending 2 mm onto the nasal cornea. One month postoperatively, the patient’s conjunctival autograft is healing well with mild chemosis that will resolve over time. Source (all): John Hovanesian, MD