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Title:  Divide-and-Conquer
Author: Troy Teeples, MSIV, Nikko Ronquillo, MD, Jeff Pettey, MD
Photographer: Troy Teeples MSIV, University of Utah School of Medicine
Date: 10/09/2018
Keywords/Main Subjects:  Divide-and-conquer, phacoemulsification, cataract surgery

Brief Description: Divide-and-conquer is a frequently used technique in phacoemulsification cataract surgery. Here we discuss the basics of performing this technique.


The divide-and-conquer technique provides an efficient and functional technique to mechanically disassemble the nucleus by sculpting grooves with the phaco probe and cracking the lens into four distinct quadrants. This simple approach can help the surgeon reduce the amount of ultrasonic energy and time needed for a routine cataract case.

Description of Technique:

The divide-and-conquer technique is begun with the creation of a longitudinal groove in the lens using the phaco probe on “sculpt” setting. The groove must be wide (at least 1.5x as wide as the phaco tip) and deep in order to facilitate proper cracking. During creation of the grooves, care should be taken not to tear the capsulorhexis edge as this may propagate to a posterior capsular tear. When the first groove is completed, a second instrument is introduced into the eye and used to assist in dividing the nucleus. This is performed by placing both the second instrument and phaco tip deep into the groove and parallel to each other, after which the nucleus is then cracked by pulling the second instrument in the opposite direction of the phaco tip.

After the nucleus is divided into two, the second instrument is used to rotate the lens 90-degrees, lining up the lens for the creation of the subsequent groove. When properly aligned, the phaco probe is used to sculpt a second groove, perpendicular to the original. The more distal heminucleus is cracked first using the second instrument and phaco tip, after which the lens is rotated 180-degrees to crack the second heminucleus. Once the nucleus has been divided into four quadrants, each of the quadrants can then be phacoemulsified individually.

Faculty Approval by: Jeff Pettey, MD
Identifier: Moran_CORE_25443
Copyright statement: Copyright 2018. Please see terms of use page for more information.
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