Comparison of torsional and microburst longitudinal phacoemulsification: a prospective, randomized, masked clinical trial

Ophthalmic Surg Lasers Imaging. 2010 Jan-Feb;41(1):109-14. doi: 10.3928/15428877-20091230-20.


Background and objective: To compare intraoperative performance and postoperative outcome of three phacoemulsification technologies in patients undergoing microcoaxial phacoemulsification through 2.2-mm corneal incisions.

Patients and methods: The prospective, randomized, single-masked study included 360 eyes randomly assigned to torsional (Infiniti Vision System; Alcon Laboratories, Fort Worth, TX), microburst with longitudinal (Infiniti), or microburst with longitudinal (Legacy Everest, Alcon Laboratories) ultrasound. Assessments included surgical clock time, fluid volume, and intraoperative complications, central corneal thickness on day 1 and months 1 and 3 postoperatively, and endothelial cell density at 3 months postoperatively. Comparisons among groups were conducted.

Results: Torsional ultrasound required significantly less surgical clock time and fluid volume than the other groups. There were no intraoperative complications. Change in central corneal thickness and endothelial cell loss was significantly lower in the torsional ultrasound group at all postoperative visits (P < .001, Kruskal-Wallis test) compared to microburst longitudinal ultrasound modalities.

Conclusion: Torsional ultrasound demonstrated quantitatively superior intraoperative performance and showed less increase in corneal thickness and less endothelial cell loss compared to microburst longitudinal ultrasound.

Publication types

  • Comparative Study
  • Randomized Controlled Trial

MeSH terms

  • Aged
  • Aged, 80 and over
  • Cell Count
  • Cornea / cytology
  • Cornea / diagnostic imaging
  • Cornea / surgery*
  • Endothelium, Corneal / cytology
  • Endothelium, Corneal / diagnostic imaging
  • Follow-Up Studies
  • Humans
  • Microscopy, Acoustic
  • Middle Aged
  • Phacoemulsification / methods*
  • Prospective Studies
  • Single-Blind Method
  • Treatment Outcome