Chop and tumble nucleotomy – A technique for safe nuclear emulsification in posterior polar cataract

A modified phaco chop technique for nuclear emulsification in posterior polar cataracts with nuclear sclerosis that avoids hydrodissection or nuclear rotation has been described. After performing a vertical chop maneuver to divide the nucleus, two pie-shaped nuclear fragments are removed from either side of the initial chop. The remaining nuclear fragments are then sequentially tumbled toward the center using the second instrument and emulsified while maintaining an intact epinuclear shell, which safeguards the fragile posterior capsule. The technique was successfully performed in 62 eyes of 54 patients with posterior polar cataract and grade II–IV nuclear sclerosis. The Chop and Tumble nucleotomy is a safe and effective technique for phacoemulsification in posterior polar cataracts with nuclear sclerosis, where hydrodissection and nuclear rotation are typically avoided

Experiments study on mechanical behavior of porcine lumbar intervertebral disc after nucleotomy under compression / 生物医学工程学杂志

In order to study the mechanical behavior of degeneration and nucleotomy of lumbar intervertebral disc, compression experiments with porcine lumbar intervertebral discs were carried out. The lumbar intervertebral discs with trypsin-treated and nucleus nucleotomy served as the experimental group and the normal discs as the control group. Considering the effects of load magnitude and loading rate, the relationship between stress and strain, instantaneous elastic modulus and creep property of intervertebral disc were obtained. The creep constitutive model was established. The results show that the strain and creep strain of the experimental group increase significantly with the increase of compression load and loading rate, whereas the instantaneous elastic modulus decreases obviously, compared with the control group. It indicates that the effect of load magnitude and loading rate on load-bearing capacity of intervertebral disc after nucleotomy is larger obviously than that of normal disc. The creep behavior of the experimental group can be still predicted by the Kelvin three-parameter solid model. The results will provide theoretical foundation for clinical treatment and postoperative rehabilitation of intervertebral disc disease.