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Bernell Tannen Flipper™


Item #: BTFLIP

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Distance horizontal, fusional vergence facility (DFF) appears to be reduced in many patients who have had concussions. Dr. Barry Tannen has examined hundreds of post-concussion patients and has devised a simple test to be used both as a diagnostic and training tool.

This special prism flipper has a combined prism of 2PD BI on one side and 4PD BO on the other. The flipper comes with a distance target, as well as instructions for testing patients. Full instructions come with the product, but a quick instruction guide is also located on the back of the laminated target card.

These flippers can be used to:
1. Help with the diagnosis of distance fusional instability
2. Record the recovery process of distance fusional instability
3. Help in the training of distance fusional facility.
Kit Includes:
- Bernell Custom Prism Flipper with (2) 1PD Base-In Lenses (2PD Range) on one side and (2) 2PD Base-Out Lenses (4PD Range) on the other side

- Laminated Target Card with letter sized for 15ft testing distance plus Quick Instruction Guide on back

- Instruction Sheet

Research Articles:

Tannen, B., Rogers, J., Ciuffreda, K. J., Lyons, E., & Shelley-Tremblay, J. (2016). Distance Horizontal Fusional Facility (DFF): A Proposed New Diagnostic Test for Concussion Patients. Vision Development & Rehabilitation, 2(3), 170-175. Click here to read the article


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