According to Dr Sabine Schriefl (Department of Ophthalmology, Waehringer Guertel, Vienna, Austria), downsizing incisions has been a driving force of the evolution of cataract surgery in recent years, however, just reducing the size of the phaco needle will lower efficacy. This was reflected in her discussion during the Phaco Techniques session that took place on Monday afternoon during this year's ESCRS congress in Vienna, Austria.

Dr Schriefl and colleagues, Dr Eva Stifter and Prof. Dr Rupert Menapace, performed a comparative study to determine the intraoperative efficacy and postoperative outcomes of two different phacoemulsification tips, the easyTip 2.2 mm and the 20G CMP tip (both from Oertli Instrumente AG, Bernecke, Switzerland).

Comparing phaco tips

The prospective, randomized, single-masked study consisted of 114 eyes of 57 patients. Dr Schriefl explained that preoperative examinations were performed 1-week before surgery. "One week before surgery, we graded all cataracts (i.e., both groups) using the Lens Opacities Classification System (LOCS) III and we measured endothelial cell density by non-contact specular microscope," she said.

To maintain integrity in the study a single surgeon performed all the operations. Dr Schriefl added, "The surgeon operated on each patient in a single session where one eye was randomly assigned to undergo phacoemulsification with the 20G CMP (group 1) and the fellow eye with the easyTip 2.2 mm (group 2). Group 1 were operated on with low fluidic setting (aspiration flow: 20 mL/min; vacuum: 400 mmHg) while group 2 were operated on with enhanced fluidic settings (aspiration flow: 35 mL/min, vacuum: 500 mmHg)."

She went on to explain that efficacy was measured in terms of surgery time (to divide and conquer the nucleus of the lens), the amount of phaco energy consumed and the fluid consumption. "The safety of each phaco tip," she continued, "was judged in terms of visual acuity (VA) and endothelial cell loss." The follow up periods for visual outcome and endothelial cell loss were 1-week and 18-months post-op. Complete analysis was made postoperatively at the end of the study.