11313 - Combination Horizontal Vertical Prism Bar
The Combination Horizontal Vertical Prism Bar provides accurate measurement of ocular deviation. Can be used alone or together. The prism bar is precisely calibrated for dual use and helps voids variable strabismus results. The bar measures primary and secondary deviations.
$220.00
Gulden's new, combination horizontal vertical prism bar addresses a problem that can occur when using two prisms simultaneously to measure ocular deviation.
The deviation neutralized by a prism bar can vary depending on how the prism is held with respect to the patients line of sight. Errors can occur if a prism or prisms are not held in the position for which they are calibrated.
When horizontal and vertical prism bars are used simultaneously in front of the same eye, they are customarily held back-to-back. This practice, however, reverses the rear prism bar from its usual position and results in an erroneous measurement.
Gulden's new, combination prism bar resolves the problem by having the horizontal prism bar slide up and down in a channel affixed to the vertical prism bar. This ensures that the flat surfaces of both prism bars are held perpendicular to the direction of the fixation object.
The vertical prism bar is calibrated in the Prentice position, and the horizontal bar is calibrated in the frontal plane position.
Primary and secondary deviations can be measured when the Gulden combination bar is used in front of one eye with the vertical prism bar closest to the patient.
The effectiveness of this new, improved design is summed up in a quote from an independent, scientific study: "Guldens new combination horizontal/vertical prism bar can be used without any significant error."
