houstonman wrote:I read on another site that it is better to have lasik done in the winter time vs summer time.
This issue is taking on urban myth proportions. There are elements of truth, but the conclusion is wrong. What has made thins worse is that a news article misquoted a doctor and moved the decimal point in the percentage of problems related to environmental conditions.
A Lasik laser is concentrated light passing through the atmosphere to its target. That atmosphere consists of many different gasses, moisture, dust, etc. The light is blocked or redirected when passing through the atmosphere. The more light that is blocked, the less laser energy arrives at the eye. The less laser energy at the eye, the less tissue is removed for each pulse. The less tissue removed than projected, the less accurate the correction.
If the relative humidity is high (no matter what time of year) there is more moisture in the air. That moisture will block the laser light more than when the relative humidity is low and the air is dry. If the atmospheric pressure is high (any time of year), the air is denser and will block more laser light than if the atmospheric pressure is low. If the room temperature is low, the molecules are less active than if the room temperature is high. This too affects the laser light.
What is important is that all laser systems require recalibration at the beginning of the surgery day and recalibration every few surgeries. If you took a laser during the summer in Death Valley at sea level and installed it in Denver in the winter without recalibration, the amount of tissue that is removed with each pulse would be different, however this does not happen.
Good doctors take into account these variables. Some have a controlled operating room with humidifier/dehumidifier, etc. The doctor adjusts the laser treatment based upon these up-to-the-minute variables.