The Effect of Pulsing on Transverse Ultrasound Efficiency and Chatter

Am J Ophthalmol. 2017 Nov:183:107-110. doi: 10.1016/j.ajo.2017.08.012. Epub 2017 Aug 30.

Abstract

Purpose: To evaluate the effects of micropulse, long pulse, and continuous ultrasound on transverse ultrasound using Abbott Medical Optics' (AMO) WhiteStar Signature Pro with the Ellips FX handpiece.

Design: In vitro laboratory study.

Methods: This study was conducted at the John A. Moran Eye Center Laboratory, University of Utah, Salt Lake City, Utah, USA. Porcine lenses were hardened in formalin for 2 hours and equilibrated in basic salt solution (BSS) over a 24-hour period. The lenses were then cubed in 2.0 × 2.0-mm pieces. These pieces were stored in BSS until the time of experimentation. The AMO WhiteStar Signature Pro machine (Abbott Medical Optics) with the Ellips FX handpiece and a 0.9-mm bent Dewey tip with a 30-degree bevel (Microsurgical Technology Inc) were used for phacoemulsification. Three runs of 20 lenses each were performed, measuring efficiency and chatter. Transverse ultrasound varied in the 3 runs and included continuous, 6 ms on/off micropulse, and 50 ms on/off long pulse.

Results: Micropulse was more efficient than long pulse by 43% (P = .00003) and continuous by 42% (P = .000387). There were also less chatter events with micropulse than with long-pulse and continuous ultrasound. However, this difference did not reach significance.

Conclusion: The 6 ms on and 6 ms off micropulse transverse 3-dimensional ultrasound is more efficient and produces fewer chatter events than both long-pulse and continuous ultrasound.

MeSH terms

  • Animals
  • Cataract / therapy*
  • Disease Models, Animal
  • High-Energy Shock Waves / therapeutic use*
  • Lens, Crystalline*
  • Phacoemulsification / methods*
  • Swine
  • Ultrasonic Therapy / methods*