With a dense cataract, there can be a fibrous posterior aspect of the lens nucleus which makes chopping more difficult. In a routine case, the vacuum of the phaco tip (at 500+ mmHg) is enough to hold the nucleus while the chopper splits it. However, with a dense brunescent cataract, this vacuum holding force is insufficient and the chop fails. To successfully chop a dense brunescent cataract, we can trap the nucleus between the chopper and the phaco probe and then push the two instruments together to mechanically divide it. This pit technique provides this advantage since a central crater is sculpted and then the phaco probe can be place against the pit wall while the chopper is placed around the nucleus equator.
Our guest surgeon is Dr. Raul Tolentino Jr. from Davao City, Philippines and he does a great job of efficiently and safely removing this dense brunescent cataract.
Click below to learn this Pit Technique for dense brunescent cataracts:
credit for very similar technique: Vanathi M et al, Crater-and-chop technique for phacoemulsification of hard cataracts. JCRS 2001 May; 27(5):659-61
Hi Dr Devgan. In the pit technique, is any vacuum applied as you chop the nucleus or is it purely a mechanical chop? It was not clear in the video.
Also use high vacuum to hold the nucleus