The purpose of this study is to compare the outcomes of cataract surgery performed with three incision-size-dependent phacoemulsification systems (1.8, 2.2 and 3.0 mm).

It is generally the case that smaller corneal cataract surgical incisions are associated with more rapid wound healing, more stable corneal biomechanical properties and less surgically induced astigmatism (SIA). With the development of phacoemulsification and foldable intraocular lenses (IOL) during recent decades, the size of clear corneal incisions has been reduced from 3.2-mm (coaxial small incision) to 1.4-mm (bimanual micro incision). Micro incision cataract surgery (MICS), including bimanual and micro coaxial phacoemulsification, has attracted much interest recently, due to its safety and ease of learning. However, the superiority of coaxial micro incision cataract surgery as compared conventional coaxial cataract surgery is still not certain, because micro incision phacoemulsification may result in longer ultrasound time (UST), the use of more ultrasonic power and consequently higher endothelial cell loss (ECL).

In our previous studies of the OZil Torsional phacoemulsification system (Infinity, Alcon), we reported that the safety and effectiveness of cataract surgery are influenced by many factors, including the blade used to create the incision, the phacoemulsification apparatus, and the IOL and mode of IOL delivery, which together constitute a surgical system, whose outcomes are restricted by the best performance of each component. Today, micro coaxial phacoemulsification is in wide use for cataract surgery, but the lower limits of incision size should be understood in the context of the various components of the surgical system.

In this study, we compared the safety and efficacy of three different incision-size-dependent phacoemulsification systems, 1.8, 2.2 and 3.0 mm, and evaluated the relationship between incision size and SIA.

Inclusion Criteria:

• age between 55 and 85 years
• the presence of nuclear or cortex-nuclear cataract, grades 2.0 to 4.0 (Lens Opacities Classification System III)
• a transparent central cornea
• pupil dilating to >= 7 mm at the time of preoperative examination
• a preoperative central endothelial cell count of >= 1500 cells per square millimeter

Exclusion Criteria:

• previous intraocular surgery
• glaucoma
• pseudoexfoliation
• uveitis
• high myopia
• diabetes mellitus

This prospective randomized study comprised 120 patients (120 eyes) with age-related cataract enrolled for surgeries between July 2010 and January 2011 at the Zhongshan Ophthalmic Center, Guangzhou, China.

Total Number of Participants at Risk for this Observational Study (e.g., serious and/or other [non-serious] adverse events were not collected/assessed).