Fogging the patient during astigmatic testing is recommended.

Fogging the patient during astigmatic testing is recommended.

• A. True
• B. False
• C. Only for high astigmatism
• D. Not needed if patient is cooperative

Answer: (A)

Fogging helps keep accommodation in check so your responses reflect the eye’s true optical error rather than the patient’s effort to focus. By introducing a little plus power, you relax the accommodative system, preventing the patient from actively accommodating to make one meridian appear clearer. This creates a more stable baseline for determining the cylinder power and axis. After establishing a fogged, relaxed state, you can gradually reduce the plus to refine the astigmatic correction without accommodation skewing the results. This is a standard step in astigmatic testing because it improves reliability regardless of how cooperative the patient is or how pronounced the astigmatism may be.

Fogging helps keep accommodation in check so your responses reflect the eye’s true optical error rather than the patient’s effort to focus. By introducing a little plus power, you relax the accommodative system, preventing the patient from actively accommodating to make one meridian appear clearer. This creates a more stable baseline for determining the cylinder power and axis. After establishing a fogged, relaxed state, you can gradually reduce the plus to refine the astigmatic correction without accommodation skewing the results. This is a standard step in astigmatic testing because it improves reliability regardless of how cooperative the patient is or how pronounced the astigmatism may be.