[Self-closing corneoscleral tunnel incision in cataract surgery]

Self-sealing wound construction in the cataract surgery can be performed sclerally or corneally (clear corneal incision). Each technique has different advantages and disadvantages concerning wound preparation, induced astigmatism, and wound closure stability with rising intraocular pressure. The corneoscleral tunnel incision could have the advantages of both scleral and corneal incisions.

We performed a trapezoid corneoscleral tunnel incision in 108 cases. The incision has a width of 7 mm and a radial length of 1.5-2 mm. In 39 patients the incision was performed at the 12 o'clock position. A lateral approach was made in 69 patients because astigmatism against the rule preoperatively. The wound closure was achieved by elevation of IOP to 30-40 mmHg without suture, as in the no-stitch technique.

In comparison to the 7-mm corneal incision, the corneoscleral incision had a higher wound stability. Even external pressure at the wound location could not provoke leaking. The induced astigmatism was examined up to 4 months postoperatively. The mean astigmatism was around 1.2 D for the superior wound preparation versus 0.5 D for the lateral approach.

The corneoscleral tunnel incision can be used routinely. The following advantages can be stated: (1) moderate cauterisation, (2) easy and reliable wound preparation, (3) high wound stability even with 7-mm incision, (4) wound opening completely covered by conjunctiva postoperatively, (5) clinically tolerable induced astigmatism. This technique can also be used if an astigmatism up to 1.5 D exists preoperatively.