Description

This is a prospective, intraindividual comparative study of two routinely used surgical techniques for IOL implantation in extracapsular cataract surgery. On the day baseline examination, the first eye to be operated is randomised to receive a 3p-IOL implantation in the capsular bag (group 1) or a 3p-IOL haptics in the ciliary sulcus with the IOL optic tucked in the capsular bag (group 2). The second eye to be operated receives the other method. The eye with the lower visual acuity is operated first, in case of identical visual acuity values the for the patient subjective worse eye is operated first. This procedure is clinical standard. Until the point of IOL implantation the surgery is identical in both methods and the surgeon is blinded.

Femtolaser is used to perform a standard 5.0mm CCC centred on the pupil or limbus and to fragment the lens nucleus to guarantee reproducible results in every eye. In case of an insufficient pupil size (smaller than 5.5mm), 2.4mm clear corneal incision and paracenteses are performed prior to laser docking and a pupil expansion device is implanted under anterior segment filling with viscoelastic to enlarge the pupil diameter. After the CCC and nucleus fragmentation the anterior segment is filled with viscoelastics, the rhexis lenticule is removed and hydrodisection of the nucleus is performed. Subsequently phacoemulsification for nucleus and irrigation/aspiration of the lens cortex is performed. The capsular bag and AC is then filled with a cohesive viscoelastic and the IOL is implanted as described above with the haptics in the back or with the haptics in the sulcus. At the end of surgery, the viscoelastic is removed using the irrigation aspiration probe, intracameral antibiotic is instilled, the CCI and paracenteses are hydrated and sealed.

Study investigators are blinded, however the selected method can be visible during the routinely performed slit-lamp examinations. During all evaluation and measuring processes (Evaluation of decentration, tilt, capsular phimoses, surgery time) the investigators are blinded. This study is performed by highly experienced surgeons, who have already performed both methods on a routine basis.