gms | German Medical Science

Purpose: To present test data and initial clinical results for a new disposable capsulotomy device called Zepto^TM (Mynosys Inc. Fremont, CA. USA).

Methods: Miyake-Apple imaging to examine zonular effects and scanning electron microscopy (SEM) to investigate capsulotomy edge morphology. Rabbit GLP study comparing ocular condition after Zepto^TM or CCC. Comparison of Zepto^TM edge strength and extensibility to CCC or femtosecond laser in paired cadaver eyes. 10 patients (49 to 85 y.o.) with lens cataract received Zepto^TM capsulotomy, phacoemulsification and a one-piece acrylic IOL.

Results: The Zepto^TM disposable handpiece with capsulotomy tip is connected to a console. The tip has a soft, clear silicone suction cup within which a circular superelastic nitinol capsulotomy element is embedded. The tip is elongated to fit through a 2.2 mm incision and allowed to regain to its circular shape the anterior chamber. After centering on the pupil or visual axis, suction is applied followed by a 4 milliseconds multipulse algorithm to create round circular capsulotomies. Suction is reversed and the Zepto^TM tip is retrieved from the anterior chamber.

Zepto^TM produces consistently round capsulotomies with no zonular stress. The capsulotomy edge is smooth by SEM with a slight eversion of the defect-free underside of the capsule. Rabbit eyes with ZeptoTM capsulotomies had a benign post-op course with no difference to CCC eyes. The Zepto^TM edge was 3-4 times stronger than the CCC (P=0.012) and the femtosecond laser edge (P=0.012). Zepto^TM edges were also more extensible than CCC (P <0.01) and femtosecond laser edges (P <0.01). (Wilcoxon matched-airs signed ranks test.)

Complete, free-floating capsulotomies were achieved in all 10 patients. Zepto^TM performed well in challenging cases including in 3 patients with pterygium limiting capsule visualization, 2 patients with dense cataracts and poor red reflex, and 2 patients with poor pupil dilation. No capsulotomy related adverse events were noted up to 4 weeks after surgery.

Conclusions: Zepto^TM produces consistent, round capsulotomies that are stronger and more extensible than that of CCC or femtosecond laser. Zepto^TM performed well in initial clinical study and appears to have good potential for safe, consistent capsulotomies in challenging cases.