This video demonstrates how to vertical chop dense cataracts.
Key points:
1. Make main wound and paracentesis pointing nasally, to maximize angle of approach to chop the cataract. By having wounds directed nasal, it facilitates down and out chopping motion with the second instrument, which allows the cataract to split with relative ease. Additionally, nasal directed wound position allows horizontal chop to be performed with ease. A good analogy of vertical chop is an ax chopping wood with 1 cut.
2. Prior to hydrodissection, burp some viscoelastic out of the anterior chamber to de pressurize the eye, otherwise hydrodissection may rupture the posterior capsule.
3. Dense cataracts are very solid. To facilitate the chop, first dig a hole in the middle of the nucleus, so the phaco tip can grab deep into the body of the nucleus, which will allow the nucleus to split. If you only grab the anterior surface of the cataract, the vertical chopper will simply push the cataract off the phaco tip.
4. The most important instrument in vertical chop is the phaco tip. The phaco tip needs to have adequate tip exposure, and there needs to be high, fixed vacuum (380-450 mmHg), in order to be able to bury the phaco tip and hold tightly on to the nucleus. Once there is a good hold on the nucleus, the second instrument can easily split the cataract.
5. A sharper tip chopper needs to be used so can incise into the dense nucleus.
6. The chopper tip should be placed just anterior to the phaco tip, in a central position. If the chopper is placed too close to the phaco tip, the vacuum hold on the nucleus will be broken, and the phaco tip will lose its hold.
7. Make multiple chops in the bag, then start to take out the pieces.
8. When pieces start coming out, change to a less sharp chopper, so will not risk puncturing posterior capsule.
