New disposable ceramic cut like Stefanie Petrou Binder MD steel edge was dramatic, demonstrating welcome development. seemed to require the most amount of in Paris an uneven and serrated edge profile. He They explained that the physics involved in pressure 40 mmHg to cause wound gape, he explained that the steel edge imperfections measuring blade sharpness is very complex. reported. A NEW prototype atomic edged (BD) were an artefact of the manufacturing To measure the sharpness of the three The team investigated wound healing using disposable ceramic blade approaches the sharpening process. different blades, the researchers defined it as light microscopy (LM) of corneas fixed at quality of a blade while offering the He investigated the corneal wound profile the force required to four hours and four days following incisions, convenience of a disposable, according to by using scanning electron microscopy (SEM) in each group.They recorded epithelial Romesh Angunawela MRCOphth,The Rayne of central corneal stab incisions and linear penetrate the test medium, using a micro- closure rates with a tandem scanning Institute, St Thomas’ Hospital, London, UK. incisions of fixed organ cultured human drive and a strain gauge to measure the confocal microscope. “The performance of this corneas.According to cross sections of the forces, in Newtons (N) per square There was no distinguishable difference in disposable prototype atomic edged blade is electron micrographs of mini-incisions, the millimetre.The repeatability of this method corneal wound healing between the three an improvement on conventional steel and corneal cut morphology appeared clean and was within an acceptable range (+/- 3.56 blades based on LM analysis. Epithelial brings this disposable blade closer to the smooth with the diamond and atomic blades, N/mm2). closure rates were comparable for all three bench mark diamond blade in performance,” while the morphology after steel blade As expected, the diamond required blades with complete closure of the wound Dr Angunawela told the XXII Congress of the incisions was not. the least force, 2.24 N/mm2 (SD 0.06), to gape by 36 hours. ESCRS. Dr Angunawela pointed out that the effect penetrate the test medium.The steel blade “It would appear that this novel ceramic Dr Angunawela used electron microscopy of the shearing force of the steel blade as it required much more force, 71.94 N/mm2 blade approaches the performance of traversed (SD 3.56), while the force required of the diamond blades with the added convenience through the ceramic blade lay somewhere between the of single use. I am told by the manufacturers corneal stroma two, 42.10 N/mm2 (SD 1.93). (BD) that the cost should be comparable to caused irregular In addition to the objective, measurable that of steel blades,” he affirmed. stromal damage. data presented by the investigating team, There was little some of the surgeons participating at the [email protected] observable congress were curious about the subjective difference in the feel of the knife, saying that experienced wound profile of surgeons have a feel for the cut they are the atomic edged making and the sharpness of the instrument and diamond they are using. Dr Angunawela could verify blades on SEM, his results, confirming from his viewpoint that which both the atomic edged blade felt closer to a appeared diamond than steel knife when penetrating smooth. tissue. According to Dr Angunawela and his team studied the the investigators, pressure required to cause wound gape

Courtesy of Romesh Angunawela MD the risk of following corneal incision.The corneas were transmissible maintained in normal culture for a week to compare the cutting edges of the three primary infections during surgery is a very before the researchers pressurised them and blade types, unused stainless steel, diamond, real risk for British ophthalmic surgeons. observed for wound gape through an and the new disposable atomic edged blades. Therefore, an increase in the use of operating microscope. While the cutting edges of the diamond and disposable instrumentation, not only in The diamond incisions performed worst, ceramic blades were relatively smooth under cataract surgery but also in corneal and causing wound gape at pressures as low as electron microscopy, the difference to the refractive surgery, seems a logical and 20 mmHg. Surprisingly, the atomic edge blade