Intraocular antiseptic doubles as medium for Seidel testing
in San Francisco, US
POVIDONE-iodine 5% solution (Betadine) is a useful, convenient and cost-effective material for performing Seidel testing of wound integrity at the conclusion of no-stitch cataract surgery, according to Gary S Schwartz MD.
When povidone-iodine solution is applied to the paracentesis and phaco incision sites at the conclusion of the case, wound leakage can be easily detected as streaming of clear fluid through the brown puddle of the antiseptic, he told a session of the annual ASCRS Symposium on Cataract, IOL and Refractive Surgery.
Reviewing his experience using this technique in a consecutive series of 65 eyes, Dr Schwartz reported that 25 (38%) eyes were Seidel positive with initial testing, having leakage at the paracentesis and/or temporal wounds.
The paracentesis wound was identified as leaking in 11 eyes, 10 eyes had leakage of the entire temporal wound. In 10 eyes only half of the temporal wound was leaking.
Six of the eyes tested Seidel positive at both the paracentesis and temporal wounds.
Wound integrity was achieved in all of those cases using hydration without any need for sutures. Some wounds were sealed after hydration only once, but some were still leaking when the Seidel testing was repeated and were hydrated a second time.
No wounds were found to be leaking on the first postoperative day. This indicates both that the sites testing Seidel negative were intact and that the hydration was effective for sealing the leaking wounds, he noted.
Dr Schwartz reported there was no evidence of intraocular damage attributable to the povidone-iodine application or any cases of postoperative endophthalmitis. He acknowledged that that rare complication would be unlikely in this small series of eyes. "Povidone-iodine 5% solution remains a benchmark as a safe and effective agent used preoperatively to decrease the risk of endophthalmitis after cataract surgery and many surgeons instill it at the end of the case as added protection against infection.
"Many techniques can be used to check the integrity of the wounds in no-stitch cataract surgery, including Seidel testing with fluorescein strips.
However, povidone-iodine is a safe and effective alternative for identifying wound leakage, and because it is usually already available, it can be used for that purpose without any added cost," he commented.
Dr Schwartz’s technique for performing cataract surgery involves the creation of a 3.5mm clear corneal temporal incision with placement of a 3-piece, foldable acrylic IOL. The eyes are prepped in standard manner by placing povidone-iodine 5% sterile ophthalmic prep solution into the cul-de-sac. A fluoroquinolone antibiotic is also instilled immediately preoperatively.
After the surgery is completed, he applies two to three drops of povidone-iodine 5% to the limbus at the sites of the temporal and paracentesis wounds. Leaking wounds are hydrated with balanced salt solution, although if only part of the temporal wound is leaking, the hydration is restricted to that area. The Seidel testing is repeated after the hydration and hydration performed again as needed. Any wound still Seidel positive after a second hydration is sutured.
"Leaking wounds can be closed with hydration or suturing. However, wound hydration causes postoperative corneal oedema and decreases clearing of the visual axis and suturing adds time and expense to the surgery.
Therefore, it is best to recognise eyes which are truly not watertight and reserve hydration and/or suturing for those cases," Dr Schwartz said.
He uses the marketed sterile ophthalmic prep solution containing 5% povidone-iodine, but he noted the commercially available 10% solution can also be diluted 1:1 with sterile saline. However, he cautioned that surgeons should not apply the undiluted 10% preparation directly to the cornea because it is toxic, nor should they dilute Betadine 10% Surgical Scrub.
Gary S Schwartz MD
University of Minnesota, Minneapolis, US