The Eight-Chop Technique: Mechanistic Principles and Clinical Performance of a Segmentation-First Phacoemulsification Strategy

Purpose: To review the conceptual evolution, mechanical principles, and clinical outcomes of the Eight-chop nuclear fragmentation technique, and to clarify its position within modern cataract surgery. Methods: A narrative review was conducted focusing on the historical development of nuclear fragmentation strategies, including sculpting-based techniques, divide-and-conquer, chop-based methods, femtosecond laser–assisted cataract surgery, and prechop techniques. Particular attention was given to the wedge-induced fracture mechanism, geometric optimization through eightfold division, and integration with modern fluidics systems. Published clinical studies and the authors’ clinical data were analyzed across a wide range of cataract subtypes. Results: Across standard cataracts and challenging conditions—including dense nuclear cataracts, white cataracts, small pupils, shallow anterior chamber, microcornea, diabetic eyes, and pseudoexfoliation syndrome—the Eight-chop technique consistently demonstrated reduced phaco time, cumulative dissipated energy, and irrigation volume compared with conventional techniques. Corneal endothelial cell density loss was generally limited to approximately 1–3%, even in high-risk subgroups. Postoperative intraocular pressure showed a sustained reduction over mid- to long-term follow-up. These subtype-specific outcomes are integrated in Table 1, highlighting the reproducibility and low invasiveness of the technique regardless of nuclear hardness or anterior segment anatomy. Conclusions: Eight-chop is a segmentation-first nuclear fragmentation strategy based on complete in-the-bag prefragmentation using a wedge-induced fracture mechanism. Its compatibility with modern fluidics systems, including AFS, enhances anterior chamber stability and reinforces its minimally invasive profile. By reducing energy use, fluid load, and zonular stress, Eight-chop represents a rational and versatile option for contemporary cataract surgery, particularly in high-risk eyes.