Nine-Year Safety with Self-sealing Corneal Tunnel Incision in Clear Cornea Cataract Surgery

Section: Resultsmentioning

confidence: 99%

Topical anesthesia: Possible risk factor for endophthalmitis after cataract extraction

García-Arumí

Fonollosa

Sararols

et al. 2007

“…The role of unsutured clear corneal incisions for cataract surgery and the apparent increased incidence of postoperative endophthalmitis in many reports are under intense scrutiny. [1][2][3][4][5][6] Clear corneal incisions, which involve an incision in the plane of the cornea with a length equal to 2.0 mm, were first described in 1992 (I.H. Fine, MD, ''SelfSealing Corneal Tunnel Incision for Small-Incision Cataract Surgery,'' Ocular Surgery News, May 1, 1992, pages 38-39), and we continue to construct them in essentially the same manner in our practice.…”

Section: Discussionmentioning

confidence: 99%

Profile of clear corneal cataract incisions demonstrated by ocular coherence tomography

Fine¹,

Hoffman²,

Packer³

2007

116

Results indicate an incision in the plane of the cornea with a chord length of at least 2.0 mm provides advantageous architecture for adequate self-sealing. Proper clear corneal incision construction resulted in an incision architecture that seemed to have increased stability and added safety, contributing to an absence of endophthalmitis for more than 10 years and 9000 cases in a single practice.

“…It is interesting to note, however, that some surgeons report no greater rate of infection using CCIs. 15,22 With appropriate use of aseptic methods, including careful draping, chemoprophylaxis, and, particularly, CCI design, construction, and sealing, risks for infection should be acceptably low. 23 …”

Section: Resultsmentioning

confidence: 99%

ASCRS White Paper

Nichamin

Chang

Johnson

et al. 2006

The relationship between unsutured clear corneal tunnel incisions and an increased incidence of infection after cataract surgery remains uncertain; however, there is a growing concern and body of evidence regarding a potential causal association. Although 2 large recent studies from the Bascom Palmer Eye Institute report no greater incidence of endophthalmitis with corneal incisions than with sclerocorneal tunnel incisions, 1,2 the bulk of the recent literature suggests that post-cataract endophthalmitis is more likely with corneal incisions (Table 1). 3-6 The concern is fueled by the clear evidence of an increased rate for post-cataract infections since 1994, the timeline for the widespread use of unsutured clear corneal cataract incisions. 7 Indeed, laboratory models indicate that corneal tunnel incisions do not provide hermetic sealing under certain conditions. 8-10 These investigations suggest that the incisions may be competent at physiologic levels of intraocular pressure (IOP) but fail when IOP is lowered.Critics of the reports, in which human cadaver eyes are used, raise the valid issue that post-mortem eyes lack the corneal endothelial pump mechanism thought to be partly responsible for maintaining incisional self-sealing. Nonetheless, there is a genuine concern regarding the relationship between clear corneal incisions (CCIs) and rates of postoperative infection, suggesting that we carefully evaluate the potential. A recent report in this journal 11 revealed that all cases of endophthalmitis at the Moran Eye Center at the University of Utah from 1996 through 2002 were associated with unsutured clear corneal incisions. During this period, in accord with the record review, no cases of infection were associated with sclerocorneal incisions. POTENTIAL RISK FACTORSWhat factors might account for a greater risk for infection after CCIs? One might consider the absence of an overlying, separate external conjunctival closure as potentially causal. However, this would imply that sclerocorneal incisions routinely have a meticulously and watertight conjunctival closure overlying the external aspect of the scleral tunnel; this is a seemingly unlikely scenario. Moreover, in virtually all anterior segment procedures, a clear corneal paracentesis is performed and there has generally been little to no association between well-constructed, small side-port incisions and increasing rates of postoperative infection, although a change from the traditional location may have some bearing, as discussed below. Furthermore, corneal transplantation requires a 360-degree CCI and rates of infection after corneal transplants are reportedly lower over the past decade. 12 Of course, corneal transplants are generally meticulously sutured.If paracenteses and corneal transplants are at low risk for infection and clear corneal cataract incisions potentially present a higher risk for endophthalmitis, what factor(s) could account for this paradox? Wound architecture is the only logical answer. One theory suggests that ocular hypotony due to w...