The capsulorhexis is important for successful cataract surgery because it gives the capsular opening strength during cataract removal and allows for stable, long-term positioning of the IOL.
We can create the capsulorhexis using forceps or a bent-needle (cystotome) and we aim to make it round, well-centered, and about 5 to 5.5 mm in diameter for most cases. For these manual techniques, it is helpful to measure first to get an idea of the appropriate size prior to starting the capsulorhexis.
We can also use automated devices such as a femtosecond laser or units like the Zepto device which uses an electrical discharge, to create a consistent capsulotomy for every case.
In the video shown here, I use forceps which have been marked to guide me. At the beginning, prior to starting the capsulorhexis, I measure the anticipated position and diameter. Then I start the tearing of the anterior lens capsule and then stop and re-measure just to be sure. Then after completion of the capsulorhexis, a final measurement is done to confirm the correct diameter.
Click below to see the video of measuring for the perfect capsulorhexis:
Where would you prefer to use a cohesive viscoelastic rather than a dispersive visco to make the capsulorhexis ?
A cohesive viscoelastic, like you suggest, would make it easier to do the capsulorhexis since it would maintain the chamber better. The dispersive viscoelastic is better for corneal endothelial protection but it makes the capsulorhexis a bit tougher. For an expert surgeon this should not be an issue.
went twice through the video, the essence is to place the 2,5 mm mark at the center, view the tip and the 5 mm mark and do the rhexis
Dr. Devgan, which forceps do you use for capsulorhexis?