New Orleans-Leading cataract surgeons agree that the introduction of the clear cornea incision (CCI) offers advantages with respect to surgical efficiency and visual recovery, and they also recognize that there has been a recent increase in the rate of postcataract surgery endophthalmitis. However, the role of the CCI in the rising infection incidence is more controversial.
Speaking at "Spotlight on Cataracts 2004: Cataract Controversies", Peter J. McDonnell, MD, presented data from an extensive, systematic review of the English language literature and analysis of the Medicare database to demonstrate that the occurrence of postcataract surgery endophthalmitis has increased in the United States in recent years. While he noted that pattern is temporally associated with the introduction and increased use of the CCI, Dr. McDonnell acknowledged there is no proof for a causal relationship.
However, he also presented evidence from two studies performed at Wilmer Eye Institute-one in the laboratory using eye bank eyes and the other in the surgical setting-to demonstrate a mechanism by which the CCI might allow ingress of contaminated ocular surface fluid into the anterior chamber.
"We believe that attention should be directed to acquiring better understanding of both the dynamics of clear cornea incisions in the early postoperative period and the mechanism for the rising incidence of endophthalmitis," Dr. McDonnell said.
Speaking in defense of the CCI that he introduced, I. Howard Fine, MD, emphasized that acquiring skill in performing that incision involves a learning curve, and its potential for risk depends on how well the incision is done.
"We have performed 7,000 cases of cataract surgery with a clear cornea incision over the last 8 years without a single case of endophthalmitis and don't think that record is due to good luck. I am not here to sell the clear cornea incision, as I believe surgeons should use whatever incision they can perform with the most reproducibly safe results. Clearly, however, not all clear cornea incisions are the same," Dr. Fine said.
He raised questions about the clinical relevance of the methods used in the studies Dr. McDonnell described. In addition, Dr. Fine suggested that changing bacterial resistance to the antibiotics used for cataract surgery prophylaxis may be another contributing factor to the recent increasing incidence of endophthalmitis.