But new Johns Hopkins research in mice suggests that neural stem cells, the bodyâs source of new brain cells, are resistant to radiation, and can be roused from a hibernation-like state to reproduce and generate new cells able to migrate, replace injured cells and potentially restore lost function.
Pupillary Distance (PD) You'll need to know your PD if you want to order glasses from EyeBuyDirect. Don't worry if your glasses prescription doesn't include your PD, we can show you how to measure it by yourself. How to measure your pd
Ask Your Doctor. You can also get this information from your doctor or from a licensed optician. If you have two PD numbers on your prescription, you have either been given both the Distance/Reading or Right Eye/Left Eye. Here's what you do: Two same number: (Ex. 30/30) Add them together (Ex. 60 is your PD). Two low numbers*: (ex. 30/31) The first number is for the right eye (O.D.) and the second number is for the left eye (O.S.). *Place it in the Customer notes section of the order form. Two high numbers: (Ex. 62/59) First number is your Distance PD and the second is your Near PD (for reading-only glasses). As a Guideline: Most adults' PD's are between 55-65. Most kids' PD's are between 42-54.