Transient keratometric mire distortion is usually due to what factor?

Transient keratometric mire distortion is primarily attributed to the quality of the pre-ocular tear film. The tear film plays a crucial role in achieving a stable optical surface for the eye. When the tear film is unstable or disrupted, it can cause distortion in the reflected mire patterns observed during keratometry.

This distortion can manifest as changing reflections and irregularities in the mire's appearance, which may affect the accuracy of keratometric readings. The tear film can be influenced by various factors, including environmental conditions, the patient's blinking pattern, and any existing dry eye issues. Ensuring a stable and sufficient tear film is essential for obtaining accurate keratometric measurements.

While corneal irregularities, lens materials, and the age of the patient can impact overall vision and eye health, they are not the primary causes of transient mire distortion. Instead, they may be responsible for consistent changes in the cornea or vision rather than transient effects seen during keratometric assessments.