Do you feel a Headache and Fatigue even if you wear glasses??
How often you are having headaches, fatigue and heaviness even if you wear glasses all day? Fatigue and heaviness at the end of the day for glass wearer is very often? So what may be the reason behind it?
Yes, change in the prescription can be the main reason behind this but what if the prescription has been recently reviewed or is the same as glass.
Interpupillary distance ( IPD ) might be the reason which can play a significant role which leads to these symptoms.
Especially if you are having a high prescription for astigmatism, incorrect pupillary distance (PD) can affect your well being. Notable incorrect PD can cause headache, nausea, fatigue and blurry vision. While the small error in PD with a complex prescription might give you a headache sometimes.
What is PD or IPD?
Pupillary distance ( PD ) or Interpupillary distance ( IPD ) is the distance( in mm ) between the centre of the pupil of both eyes. This measurement is used while making prescription glasses. The optical centre of the lens should be overlapping the IPD is very important for making glasses. for multifocal or progressive lens we need to take segment height as well and proceed along with IPD accordingly.
However, it’s easy to measure the IPD and validate when measured by an eye care professional we will not discuss it.
![IPD measurement of an eye]()
Why and How wrong IPD can affect our well being?
The ophthalmic lens is having to change optical properties depending on where you look through it and light will not focus on the region where it should fall to have a sharper and clearer vision if the optical centre is not aligned with IPD. When the optical centre is not aligned with IPD these bent rays of light falls on the retina and then the problem starts occurring. The visual cortex in our brain is working overtime to fix these bent rays or visual signals.
Like our computer or cell phone overheating when we give a command to CPU for lots of computing or multitask. so our brain is going to tell us that things are not going well through symptoms like headache and fatigue.
So always asks your eye doctor to write IPD along with the Prescription.
Author: Rajeev Karki (Optometrist)
