Focus on Perimeters
Carl Zeiss Meditec
Carl Zeiss Meditec offers three perimetry instruments: the Humphrey Field Analyzer, the Humphrey FDT, and the Humphrey Matrix, each of which it says fits naturally into each individual practice for optimized workflow, better patient/practitioner comfort, and value today and in the future.
The company says this is the industry's broadest selection of perimetry products, and that it "continues to set the gold standard for quality, precision and innovation worldwide."
Phone: (800) 342-9821
You can operate the Octopus 301 perimeter from Haag-Streit USA from any side. It connects to a standard PC for use with PeriTrend Software Analysis Programs; provides automatic pupil measurement; and is portable.
According to the company, using the TOP strategy, you can perform a full-threshold exam in a little more than 2 minutes. The company also notes that the Octopus provides 100% eye fixation control, which results in more accurate test results, and that a seven-in-one report gives a precise assessment of the visual field.
Phone: (800) 787-5426
ACCUMAP OBJECTIVE PERIMETER
It is now possible to do perimetry without the subjective patient response, thus avoiding the potential inaccuracies of standard automated perimetry.
The AccuMap Objective Perimeter uses multifocal Visual Evoked Potential technology to present stimuli on a screen and then picks up electrical responses from the patient's visual cortex, with no required response from the patient.
The test pattern is comprised of 58 zones alternating black to white, covering the central 30 degrees. During the test, the patient fixates on a target in the center of the screen, while a patented four-electrode cross placed on the back of the head monitors electrical activity to the brain.
With the collected data, the patient's results can be compared with a normative database to identify potential abnormalities. In addition, the analysis software includes an asymmetry calculation to look for other irregularities.
In a study presented by Graham et al. at the 2004 ARVO meeting, a review of 436 tests showed an AccuMap sensitivity of 97.5% (95% in early glaucoma), and that the instrument was useful in assessing excessive field loss (45 eyes) compared with standard perimetry.
MP-1 MICRO PERIMETER
Nidek Technologies America, Inc.
The MP-1 Micro Perimeter from Nidek performs both digital perimetry and nonmydriatic fundus imaging. High-speed tracking software makes it possible to overlay the two resulting maps. Combining these two data sources allows clinicians to see where visual field defects coincide with visible structural anomalies.
In addition, the MP-1 can perform special functions such as delineating scotomas. According to Nidek, these abilities make the instrument especially useful for mapping visual function before, during and after treatment.
The MP-1 performs microperimetry using selectable target strategies and user-programmable parameters that allow the clinician to choose target number, intensity, shape and size, as well as position strategies and foreground/background colors.
Fully automated exams can also be performed using selected strategies based on standard Goldmann targets, operator-defined targets or bitmaps.
EASYFIELD, CENTERFIELD, TWINFIELD
Oculus offers three perimeters: the Easyfield, the Centerfield, and the Twinfield.
The Easyfield has a color LCD display and a fixed-point grid with 79 locations (including 30-2, 24-2, and 10-2) to test full/normal, fast and three different suprathresholds out to 30º. Oculus says recent studies show that the Easyfield has higher specificity and sensitivity than other perimeters, and that it quickly compares results with its age-related normal database. Its statistical functions include gray scale, cumulative loss curve and indices calculation. The Easyfield is also available in a laptop-controlled model.
The Centerfield, according to the company, is the only portable 36º/70º static/kinetic/multicolor perimeter that delivers optimal results even in a lighted room. It offers white/white and blue/yellow perimetry; screening mode; supra, fast, and normal threshold measurements; and 30-2, 24-2, and 10-2 grids. The Centerfield is designed for use with a Windows laptop or PC and has a full statistics package. A new, faster optional "CLIP" strategy is also available.
Oculus calls the Twinfield the "ultimate in full-field perimetry" (90º). This instrument provides Goldmann standard automatic or manual kinetic and static perimetry; white/white, blue/yellow or red/white stimuli/background colors; static perimetry with supra, fast or classic 4-2 threshold strategy; pre-programmed or hand-picked test point grids; gray-scale/scotoma curve; and 3-D animation displays. The "CLIP" strategy is available on this instrument as well.
Oculus says that each of the three perimeters have a 30-cm radius bowl, are compact and economically priced.
OPTIFIELD EP-900 SERIES
Synemed offers the Optifield EP-900 series of automated perimeters. All instruments are full-field capable and produce the industry standard printouts.
The company says the EP-900 series utilizes the latest, quickest and most sophisticated testing strategies, including the Field Trend advanced software for patient data storage and statistical analysis.
Phone: (800) 777-0650
Other Products & Services
The Rousseau Slit Lamp Mounted Marker from Rhein Medical is available for a 30-day surgical evaluation without obligation.
SLIT LAMP-MOUNTED MARKER
The Rousseau Slit Lamp Mounted Marker from Rhein Medical facilitates accurate axial alignment.
It's designed to mark the X and Y coordinates at the 6 and 9 o'clock positions. The company says it ensures a more perfect mark than handheld markers.
Etched calibration marks align with most standard Goldmann tonometer housing units to ensure exact horizontal alignment.
The stainless steel marker is reusable and autoclaveable.
Phone: (800) 637-4346