Visual field testing used to have drawbacks – it was time-consuming for you, and it fatigued patients, especially the elderly, who, as you know, have limited endurance. But today’s perimeter manufacturers are working to solve these and other perimetry problems of the past.

The newest perimetry equipment is more automated and user-friendly than it used to be, and sometimes even wheelchair-accessible. You can use data collected during testing more effectively because of computerization and today’s networking capabilities. Today’s perimeters are also easier to operate, so that you can train your staff to use them and free more of your time by delegating. Results are reliable and generated promptly, making your practice more efficient.

Here, we’ll tell you what you should know about the various perimeters out there – and give you some guidelines about how to bill once you’ve used them.

When billing for perimetry, make sure you know when to use the three codes in Current Procedural Terminology (CPT):

• Code 92081.
This code covers limited visual field examination (unilateral or bilateral), with interpretation and report (tangent screen, Autoplot, arc perimeter or single stimulus level automated test such as OCTOPUS 3 or 7 equivalent).
• Code 92082.
Use this code for intermediate examination (2 isopters on Goldmann perimeter, or the semiquantitative, automated suprathreshold screening program, Humphrey suprathreshold automatic diagnostic test, OCTOPUS program 33).
• Code 92083.
This code is for extended examination (Goldmann visual fields with at least 3 isopters plotted and status determination with the central 30°; or quantitative automated threshold perimeter, OCTOPUS program G-1, 32, or 42; or Humphrey visual field analyzer full threshold programs 30-2, 24-2 or 30/60-2).

Even if you use the correct codes, keep these issues in mind:

• Screening visual fields isn’t a covered service and can’t be performed as part of a comprehensive work-up. The test must be medically necessary.
• Perimetry is a unilateral/bilateral test by CPT description. Medicare has recently recovered huge amounts of money from practices that billed separately for each eye.
• The level of the test must correspond to the medical condition. For example, pre-operative blepharoplasty fields documenting superior field loss are not at the 92083 level.
• There are professional and technical components to billing. If you don’t interpret findings, and the test is done just for an outside physician, append modifier -TC. If you do the report, but don’t own the equipment, append modifier -26 to the appropriate code.
• Interpretation and report are required for all three codes and should be part of the medical record, along with a written order for the test. Medicare states that the findings, clinical issues and comparative data should be noted.

Billing for perimetry can be confusing, but if you follow these guidelines, you’ll minimize your problems.

– Riva Lee Asbell, Philadelphia

Ms. Asbel has written "Evaluation & Management Coding – A Comprehensive Guide" and "History – The First Key Component." Call 1-800-701-7643. Ask for #414 and #417.

Topcon’s newest ophthalmic instrument features complete screening and threshold testing, and a very compact design.

The SBP-3000 operates through an enclosed hemispherical projection screen that simulates Goldmann testing parameters.

The enclosure eliminates illumination problems, such as reflections, and it allows you to work with patients in normal room lighting.

Another advantage is the unit’s automated Windows-based program, which ensures speedy testing and data input, with easy upgrade versatility. A built-in hard disk provides data storage for 500,000 patients. The list price is $10,990.

The MS-30 features a multi-stimulus testing strategy. It’s also compact and portable, letting you maneuver better and take it with you to satellite offices or nursing homes.

Multi-stimulus testing reduces patient fatigue and is simple for the operator to set up. Data is displayed on a printout. Standard testing, including Central 30 tests and full threshold, are also available.

The computer system that powers the MS-30 is easily upgradable in your own office, so you’re protected against obsolescence. Future software upgrades are also in the works. The MS-30 costs $7,500 with the perimeter, table and table top included.

These two perimeters perform full threshold testing with Tendency Oriented Perim-etry in about 2 minutes. This minimizes chair time and maximizes tech time. Real-time fixation control systems ensure test results are 100% reliable. Critical field areas are prioritized in stages to maintain accuracy. These units are networkable, letting you link with other doctors.

The 101 perimeter offers computer-assisted kinetic perimetry to improve time management. It performs blue-on-yellow tests to detect early vision loss. Suited for a large practice, it offers 90° full field projection and a sophisticated array of tests. The 1-2-3 perimeter, performing at high speed in ambient office lighting, takes up little office space and works the fastest.

OCTOPUS has also combined kinetic Goldmann perimetry and static perimetry. OCTOPUS 1-2-3 costs $11,900; OCTOPUS 101, $22,850. The kinetic option is also available.

Synemed’s ninth generation equipment is designed with affordability, low maintenance, ease of use and upgradability in mind. All four units (910, 910+, 920 and 930) are small and user-friendly, so that you can easily train your staff to operate them. A liquid crystal display makes parameters continuously accessible and easily changed.

The EP-910 has the test programs that doctors use most often. It offers quick screening (1.5 minutes per eye) with 78 targets in the full field, plus intermediate testing and central 30° fast thresholding (2 minutes per eye). The normals database provides printouts, including deviation from normal, pattern standard deviation, statistics and defect probabilities. All units can network with IBM-compatible computers for data storage and trend analysis. EP-910 costs $5,995.

Dicon’s LD 400 Full Field Auto-perimeter is compact enough for a rotating table, with rapid setup and two-button operation. It includes voice recognition and voice prompts in 28 languages. Improved algorithms, fixation checks and auto-alignment ensure quick, reliable results. Patented Kinetic Fixation reduces patient fatigue, increasing interest and comfort. The test is less than half as long as traditional threshold exams.

The Fieldlink comprises the LD 400 linked to a stand-alone PC or a laptop that runs Dicon’s analysis software. The system generates reports and labels visual fields for one patient while examining another. Screening and threshold tests are in single or multiple stimulus mode, taking less time than traditional full threshold systems. The SST (Smart Screening Thresh-old) Autoperimeter is Dicon’s newest unit, suited for high volume. It uses the new SST algorithm and Kinetic Fixation, among other Dicon features.

Field Analyzer II (models 720, 740, 745 and 750) in-creases patient comfort and test accu-

racy. All models offer SITA, the operating system that cuts threshold test time by up to 70%. Model 720 offers 11 test patterns. An ergonomically shaped bowl increases patient comfort. Handicapped patients appreciate the wheelchair-accessible table with built-in printer.

Model 740 includes 19 test patterns and features a gaze-tracking system for real-time evaluation of eye fixation without head position effects. Model 745 adds blue-yellow testing. Model 750 has a head-tracking feature and a vertex monitor to alert you if the patient backs away. All units are compact and use software to compare results to age-matched normative data. Humphrey’s table-top FDT unit produces screening results in about 45 seconds and full threshold results in about 4 minutes per eye, in normal lighting.