For coaxial instruments like the phaco probe and the irrigation/aspiration probe, what is the best position for the silicone sleeve on the tip? For the phaco probe, how much metal of the phaco needle should show? And what about for the I/A probe?
The sleeve position affects the fluid inflow to the anterior segment and that largely dictates the stability of the anterior chamber. If the sleeve is incorrectly placed too far away from the tip then the fluid inflow will leak out of the incisions, particularly when the probe is brought to the sub-incisional area. Adjusting the tip will allow the inflow to remain in the eye and create a more stable chamber, which is safer for the patient and easier for the surgeon.
For the phaco probe it is important to have a sufficient amount of metal showing from the phaco needle to bury the tip into the cataract nucleus and have enough holding power to perform the phaco chop.
click below to learn from this video about phaco tip and I/A tip adjustment: