Dr. McDonald

"Over the years, cataract surgeons have continued to pursue the goal of minimizing incision size because smaller-incision surgery has many possible benefits," said Dr. McDonald, a private practitioner in Fayetteville, AR. "It should decrease surgically induced astigmatism and improve wound strength and integrity to reduce the risk of postoperative endophthalmitis, minimize endothelial cell loss, and hasten postoperative recovery.

"The results of our retrospective chart review show that, at least in our hands, operating through the smaller incision also had a benefit for significantly reducing the early postoperative anterior chamber reaction," he added.

Dr. McDonald said he was motivated to conduct this study as a result of an experience he had as a researcher in a clinical trial evaluating an investigational non-steroidal anti-inflammatory drug for the treatment of pain and inflammation after cataract surgery. The eligibility criteria required patients to have significant flare and cells on the first day after surgery.

After enrolling about a dozen patients, however, no patients were meeting the protocol's inclusion criteria, he said.

"Reviewing our surgical technique to see if there had been any recent change to account for this situation, the only factor we identified was that we had recently switched" from performing 2.8-mm incision surgery using one proprietary platform (Millennium Microsurgical System, Bausch & Lomb) to 1.8-mm coaxial microincisional cataract surgery (MICS) using another platform (Stellaris), Dr. McDonald said.

To explore the hypothesis that the change to MICS was responsible for the quieter eyes, a chart review was undertaken that identified 43 patients who had undergone standard 2.8-mm phacoemulsification and 60 eyes operated on using the 1.8-mm MICS procedure. Dr. McDonald performed all of the surgeries in the same operating room, and the groups were similar with respect to mean cataract density and effective phaco time. After lens removal, all incisions were enlarged for implantation of either an aspheric IOL (SofPort, Bausch & Lomb) or an accommodating IOL (Crystalens, Bausch & Lomb).

Anterior chamber reactions at 3.5 to 5 hours after surgery were graded by a single individual using values of trace, 1, 1+, 2, and 2+. These grades were assigned numerical values of 0.5, 1.0, 1.5, 2.0, and 2.5, respectively, for statistical analysis.

The results showed a mean flare/cells grade of 1.26 for the 1.8-mm MICS group and 1.52 for the 2.8-mm incision group. The >20% reduction with the MICS procedure was statistically significant.

Although acknowledging that the reason for the benefit of MICS is unknown, Dr. McDonald speculated that it is probably due to decreased turbulence and increased efficiency using the smaller handpiece.