AIM:To study the effect of high-vaccum-chop combined with intermittent-energy-release technique in phacoemulsification for hard nuclear cataract.

METHODS: Sixty-eight patients(82 eyes)with age-related cataract were included in our study, all the eyes had hard nucleus classified as Ⅳ or Ⅴ. High-vaccum-chop combined with intermittent-energy-release technique were adopted in phacoemulsification of cataract, and IOL were implanted at the same time. Time of phacoemulsification, corneal transparency after operation and visual outcome were recorded.

RESULTS: The mean relative ultrasound power was 25%-60% intraoperative. The time of ultrasound phacoemulsification was 58-105s, mean 85±20s. On the first day after operation, corneal edema classified at grade Ⅰ were seen in 28 eyes,45 eyes with corneal edema classified at grade Ⅱ, and 9 eyes at grade Ⅲ, no eye at grade Ⅳ. Seventy-three eyes with visual acuity ≥0.3 the first day after operation, and 32 eyes with a visual acuity ≥0.5. One week after operation, best corrected visual acuity >0.5 were seen in 78 eyes, and 71 eyes with a visual acuity better than 0.8.

CONCLUSION: High-vaccum-chop combined with intermittent-energy-release technique in ultrasonic emulsification instrument with non-burst mode is an effective and convenient way for phacoemulsification of cataract with hard nucleus, and is especially suitable for primary hospitals.