I'm Rebecca Wu, I'm one of the comprehensive ophthalmologists at the University of Michigan Kellogg Eye Center. Today we will be talking about irrigation and aspiration. After you've removed the hard nuclear portion of your lens, you switch to the irrigation and aspiration handpiece. Irrigation and aspiration is used to remove soft lens material. This may include cortex, epinucleus, and even soft nuclear material. We also use irrigation and aspiration for removing viscoelastic from the eye. This slide shows you some of the various irrigation and aspiration handpieces. There's a 0.3 mm port, and the tip can be straight or angled. In addition, the tip can be metal or have a soft sleeve. The advantage to using a soft sleeve is that you have tighter seal at the wound, which improves the stability of the anterior chamber. This photograph shows you what the metal tips look like, and you can see that some are angled and some are straight. The silicone tips have a soft sleeve, which, again, gives you more anterior chamber stability and decreases the risk for rupture of the posterior capsule. The 0.3 mm port is closer to the distal end, and the silicone sleeve can be reused. You also have a foot pedal to think about while you're doing irrigation and aspiration. And for beginning cataract surgeons, it's important to remember to keep your foot in position 1 to continuously irrigate. Otherwise, you will have collapse of the anterior chamber. Position 2 begins irrigation and aspiration. The technique for irrigation and aspiration includes entering the anterior chamber with the port facing up. You engage cortical material underneath the anterior capsule and begin aspiration. The lens material will occlude the port, causing vacuum to rise. And once you have vacuum, you can draw the lens material into the center to strip the cortex away. You increase aspiration to remove the lens material, and frequently, it is useful to use a back and forth motion to engage additional cortex prior to removing all of the lens material. This allows you to remove larger strips of cortex at a time. You also use the irrigation aspiration handpiece to perform capsular polish. When you move to capsular polish settings, you reduce the aspiration rate and vacuum. You put the port of your irrigation aspiration handpiece directly on the posterior capsule and use a gentle sweeping or circular motion. It is very important to avoid lifting the tip until you have released the capsule. So, removing cortical material and epinuclear material can sometimes be tricky, especially in the subincisional area. Some tips for removing resistant cortex or epinucleus include using an angled irrigation aspiration tip. So in the first picture, you can see that the angled tip allows you to more easily engage the sub-incisional cortex. If you have cortical fragments that are in the center of your posterior capsule, you can use capsular polish to remove these central fragments. In addition, you can also use a J-cannula. You attach the J-cannula onto a syringe of balanced salt solution. You inflate your capsular bag with viscoelastic. Once you enter the anterior chamber with the J-cannula, you tuck the tip of the J-cannula underneath the anterior capsule. And you can actually slide it all the way underneath the iris, then you pull back on your syringe to create manual aspiration. And this allows you to remove residual or resistant cortical material in a very controlled fashion. If you have peripheral cortical material remaining, you can proceed to insert your intraocular lens. And ensuring that there's sufficient viscoelastic in the capsular bag, you can then dial or turn the intraocular lens, using the haptics to sweep the peripheral cortical fragments. In addition, if you have epinuclear material that is difficult to remove, you can use a technique called visco-dissection. Injecting viscoelastic underneath a flap of epinucleus will help to separate the epinucleus from the capsular bag. Complications of irrigation and aspiration, so when performing irrigation and aspiration, it is not uncommon to see some stria in the capsule. As you can see in the top picture, these stria appear in a radial fashion. And this occurs when the capsule is aspirated. However, if you do not lift or pull on the capsule, it frequently does not tear. However, if you do pull on the capsule, you can develop a hole in the capsular bag, which is shown in the picture on the right. In addition, zonular dialysis can occur during irrigation and aspiration. As you can see in the bottom picture, you see a clear orange zone on the right side of the lens, and this shows you that zonules have been compromised. So finally, I have a few videos to demonstrate some techniques. The first video is on irrigation and aspiration. So if you want to enter the anterior chamber with the port facing up and irrigation only. That's foot pedal position one then you engage the cornica material under the anterior capsule and begin aspiration. That's foot pedal position two. Once the lens material occludes the port, the vacuum rises and you can dry the lens material towards the center to strip the cortex. Then you can increase aspiration to remove the lens material. This is repeated until all the lens material is removed. Here the tip is occluded, vacuum is rising, cortex is stripped to the center, aspiration is increased, and the cortex is removed. If you want to remove larger portions of cortico material, you can use a back and fourth motion with your irrigation and aspiration hand piece before pulling it to the center. >> So in that video you could see the technique for removing cortical material using the irrigation and aspiration hand piece. Next we have a video on use of the J cannula to remove subincisional cortical material So, as you could see from the video. The technique of using of J-cannula for removing resistant cortical material includes opening up the capsular bag with viscoelastic. The J-cannula is then inserted and use to create manual aspiration This technique is very helpful when the capsular bag either seems floppy or is coming forward. This allows you to have control of your capsular bag, and prevent damage to the posterior capsule. Thanks for watching. Good luck in future cataract surgery.
