Müller-Jensen K, Barlinn B
Augenklinik des Städtischen Klinikums Karlsruhe.
Ophthalmologe. 1994 Aug;91(4):446-9.
Self-sealing corneal cataract procedures have been known since 1992 and are recommended for foldable silicon lenses. Our goal was a technical modification without refractive disadvantages, which would also allow for the implantation of more rigid, but less expensive PMMA lenses of high optical quality.
The "scleral stretch incision" by Freeman (1991) was applied to the corneal situation by widening the inner wound lip up to 6.5 mm; this makes it possible to implant a 5 mm optic through an outer wound opening of 4-4.2 mm. This method has been used since October 1992 on 980 patients, whereby the lamellar corneal incision was placed 1.5-1.8 mm deep to compensate for the astigmatism, if possible in the steeper meridian.
The first 107 cases were followed up for longer than 6 months; they showed a surgically induced astigmatism of 1.18 +/- 0.79 D and a postoperative astigmatism of 0.86 +/- 0.70 D. Neither postoperative infection nor hypotony was observed in any of the cases.
The modified corneal tunnel incision is recommended for 5 mm PMMA lenses; this is especially suited for cases of low to midgrade preoperative astigmatism that can be optimally improved by this procedure. In cases of pure spheric refraction, a 3 to 3.5 mm incision with foldable lens implantation is preferred.