With the Maddox rod oriented vertically over the right eye, and the red line seen below the light source, this indicates which deviation?

• A. Left hyperdeviation
• B. Right hyperdeviation
• C. Exophoria
• D. Esophoria

Answer: (B)

The Maddox rod converts the image seen by the eye it’s over into a line, while the other eye sees a point. With the rod oriented vertically over the right eye, the right eye sees a horizontal line and the left eye sees the light as a point. The relative vertical position of that line compared to the light tells you about vertical misalignment between the eyes. If the line appears below the light, the right eye’s image sits higher than the left eye’s image in the field, indicating that the right eye is hyperdeviated. So this finding points to a right hyperdeviation. If the line were above the light, it would suggest hypodeviation of the right eye. The other terms describe horizontal misalignment, not vertical, so they don’t fit this scenario.