The usefulness of a piezo-micromanipulator in ICSI in humans

I read with great interest the article on a new technique in intracytoplasmic sperm injection (ICSI) on a method of piercing the oolemma (Yanagida et al., 1999). However, after studying the two pictures in this article carefully, I could observe two different holding pipettes. From our long experience with ICSI, and of producing pipettes ourselves, I conclude from these pictures that the bulging or deformation while inserting the injecting needle in the oocytes is due to the narrow diameter of the holding pipette. If you compare it with the holding pipette in the other picture, it is much wider and gives enough support to the oocytes to avoid this phenomenon. In our experience, using a wider diameter holding pipette can dramatically reduce the degeneration rate of the oocytes after ICSI. Finally, use of the piezo manipulator may be valuable and I have no objection to it, however, the two pictures in this article cannot be compared.