During the HGN administration, which direction should you always begin testing?

During the HGN administration, which direction should you always begin testing?

• A. Right
• B. Left
• C. Center
• D. Up

Answer: (B)

Beginning the Horizontal Gaze Nystagmus test with the stimulus moved to the left provides a consistent starting point for observing how the eyes track and when nystagmus appears. As you guide the object slowly from center toward the left, you assess smooth pursuit and look for distinct, sustained nystagmus that can occur as the gaze reaches the left field of vision. Starting on the left helps standardize the procedure, making it easier to compare responses in both directions and to catch signs like the onset of nystagmus before 45 degrees and at maximum deviation. After finishing the leftward sweep, you return to center and move the stimulus to the right to complete the checks for both directions. While starting on the opposite side is possible, the standard practice is to begin on the left to ensure consistent, reliable administration.

Beginning the Horizontal Gaze Nystagmus test with the stimulus moved to the left provides a consistent starting point for observing how the eyes track and when nystagmus appears. As you guide the object slowly from center toward the left, you assess smooth pursuit and look for distinct, sustained nystagmus that can occur as the gaze reaches the left field of vision. Starting on the left helps standardize the procedure, making it easier to compare responses in both directions and to catch signs like the onset of nystagmus before 45 degrees and at maximum deviation. After finishing the leftward sweep, you return to center and move the stimulus to the right to complete the checks for both directions. While starting on the opposite side is possible, the standard practice is to begin on the left to ensure consistent, reliable administration.