Spotlight: on technology and technique
Ultrasound Plus
A newly approved biometer/pachymeter makes IOL measurements and power calculation easier than ever.
BY CHRISTOPHER KENT, SENIOR ASSOCIATE EDITOR

Advanced technology is a good thing -- but only if it's easy to use. Unfortunately, ultrasound instruments haven't always been as easy to use as ophthalmologists might like.

Now, Tomey's AL-2000 Biometer/Pachymeter (recently approved by the FDA) has raised the bar for this technology. The AL-2000 combines two essential measuring devices and an IOL power calculator in a package that's small, easy to use, accurate, and provides multiple measurement options and plenty of data storage space.

	The AL-2000 Biometer/Pachymeter from Tomey.

Measuring axial length

The AL-2000's biometer offers several features:

Range and accuracy. The AL-2000 measures axial lengths from 15 to 40 mm with an accuracy of +/- 0.1 mm and a resolution of 0.01 mm. Anterior chamber depth can range from 2 to 7 mm with lens thickness anywhere from 2 to 6 mm.

For maximum precision, the AL-2000 calculates the average value of up to 10 measurements.

Convenience. The probe has a built-in fixation light.

Audio and visual feedback. The instrument emits a series of beeps to let you know that the probe is aligned and -- if you're in automatic mode -- that multiple measurements have been recorded. Also, detailed waveforms can be displayed onscreen when you're using the biometry probe.

Multiple user options. These include:

• taking measurements in either contact or immersion mode
• normal, aphakic, pseudophakic or dense cataract modes
• taking measurements automatically or by pressing a foot-switch. If you take the measurements in manual mode, you control their number and timing.
• The probe can be hand-held or used with the patient positioned in a chin rest.

Calculating IOL power

Once you've accumulated your data, the AL-2000 can calculate the appropriate IOL power using five of the most popular formulas: SRK II, SRK/T, Holladay, Haigis Standard and Haigis Optimized. (The Haigis formulas are especially accurate when working with high myopes or high hyperopes.) The AL-2000 can also display up to three lens constants and the corresponding IOL powers, enabling you to develop effective strategies for future surgical procedures.

The AL-2000 will store all relevant parameters and information for up to 10 different lens models.

Measuring corneal thickness

Like the biometer, the AL-2000's pachymeter offers several advantageous features:

Range and accuracy. The AL-2000's pachymeter measures corneal thickness from 150 to 1,500 microns, with an accuracy of +/- 5 microns and resolution of 1 micron.

Convenience. The pachymetry probe is designed with a 45° angled tip to make measurement easier.

Multiple user options. These include measuring corneal thickness in either single or multiple mode. (In multiple mode, as many as 25 locations across the cornea can be mapped either in standard locations or as a customizable map.) You can take these measurements automatically or manually using the footpedal.

Other features and benefits

The AL-2000 also makes it easy to access all tools and options, and helps you manage the resulting data:

• A high-resolution touchscreen display provides a simple user interface that allows fast, easy access to all available programs. For example, you can move quickly from axial length measurement to IOL calculation.
• You can print out data, including numbers, graphs and waveform charts, using the built-in thermal printer. (You have the option of printing a summary of the data or an extended, detailed printout.)
• The AL-2000 comes with a PC memory card that stores data for as many as 237 patients, which you can use for statistical analysis and future reference. Additional memory cards are available if you need to expand storage capacity.
• Once you've accumulated sufficient patient data on your memory card, the AL-2000 can calculate your surgeon factor. (The instrument will store data for as many as 7 surgeons.)
• At less than 12 pounds, the AL-2000 is portable.
• The AL-2000 also has an RS-232C communication port to transfer data directly to a PC. (You can also use the memory card in a PCMCIA port to transfer patient data to your files.)

Bringing it all back home

The AL-2000 has been available outside the U.S. since 1999, and it's received good reviews for its accuracy and ease of use. For more information about the AL-2000, contact Tomey at 800-358-6639, ext. 72, or send an e-mail to sales@tomey.com.

Are you aware of new products or technology that have made (or are likely to make) a significant difference in practice? Contact Christopher Kent at kentcx@boucher1.com  to find out about possible coverage in a future issue.