Hearing loss and phacoemulsification

To determine the acoustic spectra of currently used phacoemulsification units and to contrast phacoemulsification-generated acoustic spectra with representative audiograms of common types of sensorineural hearing loss.

Mayo Clinic, Rochester, Minnesota, USA.

The acoustic spectra of 3 phacoemulsification systems (Alcon Series 20,000 Legacy, Storz Millennium, and AMO Diplomax) were recorded in an acoustically soundproofed room using a Roland VS-880 Digital Studio Workstation and analyzed with a Hewlett-Packard 35660A Dynamic Signal Analyzer.

Phacoemulsification handpiece-generated harmonic overtones produced during ultrasound mode (6.0, 12.0, and 18.8 kHz for the 20,000 Legacy and Diplomax; 7.0 and 14.2 kHz for the Millennium) were outside the range of minimal decibel loss in individuals with hearing loss. Supplemental, low-frequency, console-generated tones produced during ultrasound mode (0.4 to 2.0 kHz for the Diplomax; 0. 1 to 1.5 kHz for the Millennium) were within the range of minimal decibel loss in individuals with hearing loss.

Phacoemulsification systems with console-generated, low-frequency tones were audible to ophthalmologists with common types of sensorineural hearing loss.