The I3 SYSTEM is an advanced, microprocessor controlled, analog/digital ophthalmic ultrasound instrument. Features include B-scan mode with electronic measurement calipers and simultaneous Cross Vector A-scan, Anterior Segment B-scan mode for imaging of anterior ocular structures, Axial Length Biometry A-scan mode with Holladay-I, SRK/T, and Hoffer-Q IOL power calculations, and Standardized Equivalent Diagnostic A-scan mode for tissue characterization. The instrument has been designed to be very user friendly, with access to all modes available through a single keystroke. Images may be stored on an Iomega Zip 750 disk, across a network, or via 1.44MB floppy disks, and later recalled for additional evaluation. Hardcopy output is available either via video printer or by using an external computer to print TIFF images. Biometry IOL reports are printed using the supplied impact printer.

Posterior Segment Diagnostic B-scan mode (10 MHz): The system produces a two dimensional, 52-degree, geometrically accurate analog sector image with superior real time, resolution, and gray scale qualities. The image extends 48mm into the eye allowing imaging of objects from the lens to the orbit. B-mode images may be displayed with or without a measurement scale or a Cross Vector. The Cross Vector may be positioned anywhere in the B-scan or expanded to an A-scan view for accurate measurements. Two electronic measurement calipers may be used to make accurate measurements on the B-scan itself.

Anterior Segment Diagnostic B-scan mode (20 MHz): This mode is also called Wide Field. In this mode the sector angle is 30-degrees, and the image is magnified four times more than the B-scan. The image penetrates 12mm into the eye allowing imaging of the cornea, ciliary structures, and other anterior ocular structures. Electronic measurement calipers and the measurement scale are available. There is no Cross-Vector A-scan measurement available in the Anterior Segment B-scan mode.

Standardized Equivalent Diagnostic-A: In Diagnostic A-mode the system produces an analog A-scan with superior clinical quality using an S-shaped amplifier for tissue characterization. Accurate 2 gate measurements may be performed in both microseconds and millimeters using velocities that may be adjusted by the user. Globe and orbit modes are available, along with a tissue sensitivity reset function.

Biometry A-scan Mode: In all Biometry modes, the system produces an A-scan with superior clinical quality for accurate axial length measurements of the eye. The instrument is easily set up for either immersion or contact biometry. The instrument is designed to ensure that the internal process used to validate measurements is visible to the user. A very important example of this is the visible indication of which echoes the electronic measurement calipers (or ‘gates’) are measuring. Another example is the on-screen display of the ultrasonic velocity used to calculate the measurements reported. These features help the user to recognize a high-quality scan that will produce an accurate measurement (and consequently, when to reject lower quality scans).