Modern ophthalmic cataract surgery now employs sophisticated techniques to improve outcomes and patient satisfaction. This includes surgical systems providing better control, lasers to perform manual techniques, and intraoperative evaluation to evaluate surgical endpoints before the patient leaves the operating room (OR).
Advances in phacoemulsification
Cataract surgery involves a corneal incision as well as a paracentsis, removal of the cataract and implantation of the intraocular lens (IOL), while maintaining the pressure in the eye. Incisions are often fewer than 3 mm because implants are engineered to be placed in smaller incisions.
Modern lens removal occurs using phacoemulsification (phaco), which incorporates ultrasound to emulsify and vacuum to extract a cataractous lens. The ultrasound hand piece is connected to a phaco system, which drives the procedure using settings as dictated by the surgeon. The phaco tip, or fragmentation needle, vibrates at an ultrasonic frequency and emulsifies a cataract when connected to the ultrasonic hand piece. The tip has a hole, which allows the fragmented lens as well as irrigation solution (BSS) to be aspirated.
More from Dr. Swartz: Effectively comanaging femtosecond laser-assisted cataract surgery
Fluidics is the dynamic between the fluid entering the eye and the intraocular pressure (IOP) during cataract surgery. If pressure is maintained at a constant level, the anterior chamber is more stable. Variable control is important for successful outcomes, particularly for surgeons who desire greater control for femtosecond laser-assisted procedures (which require less power), and dense cataracts (requiring more power).1
A high and uninterrupted flow rate is ideal to draw segments out of the capsular bag while maintaining the tip in the iris plane. Venturi pumps create optimal fluidic conditions for segment removal in a stable anterior chamber. They generate much higher flow rates than peristaltic pumps and require lower vacuum levels than peristaltic systems. Systems that incorporate both pumping types are typically preferred. New systems include Centurion Vision System (Alcon), WhiteStar Signature System (Abbot Medical Optics), Stellaris Vision Enhancement System (Bausch + Lomb,), and Ocusystem ART Phacoemulsifier (Surgical Design)