Vergleich von Phakoemulsifikation und geplanter Kernexpression

Abstract

40% of cataract surgeons in German speaking countries use phacoemulsification as the procedure of choice for cataract extraction while the other 60% still use the planned extracapsular extraction. The more procedures a surgeon performs the stronger is the tendency toward performing phacoemulsification. The opening technique of the anterior capsule is chosen accordingly: for phacoemulsification capsulorhexis is preferred, while for the planned extracapsular extraction can opener - or letter box - technique is usually done. The length of the sclero-corneal incision is 3.2 mm in phacoemulsification, 6.2 mm for a PMMA posterior chamber lens implantation and 9-13 mm for the planned extracapsular extraction. We prospectively compared both procedures with each group including 100 consecutive patients. The mean irrigation volume was 96.6 +/- 48.8 ml in the phacoemulsification group as opposed to 48.1 +/- 26 ml in the planned extracapsular extraction group. The mean duration of irrigation was 130 +/- 67 sec in the first versus 129 +/- 76 sec in the second group; mean endothelial cell loss was 7.9% versus 7.1%. No correlation was found between endothelial cell loss and duration of irrigation. Mean postoperative astigmatism measured 1.0 +/- 0.49 in the first group as compared to 3.3 +/- 1.7 dpt in the second group. Except for the astigmatism, our study could not detect significant differences regarding the outcome between both procedures. There are advantages to the phacoemulsification procedure, however, such as a smaller incision (e.g. tunnel technique), a closed irrigation-aspiration system, controlled intraocular pressure and the more frequent use of capsulorrhexis. Preferred indications and possible advantages regarding intra- and postoperative complications are discussed.